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Abstract
The objective of this study was to determine the prevalence and concordance of Mycoplasma genitalium (MG) among Mexican American and African American women and their male sexual partners. Secondary objectives were to determine symptoms of MG infection and persistence of MG after antibiotic therapy. Heterosexual couples were tested for MG and interviewed separately regarding symptoms and behavioural/epidemiologic variables at baseline, six and 12 months. The overall prevalence of MG among women and men was 9.5% and 10.6%, respectively. Subjects were five times more likely to be infected with MG if their sexual partner was MG positive. Among men and women, MG prevalence and mean bacterial loads were similar after receiving single-dose azithromycin, doxycycline or no antibiotics. MG was associated with current urethral discharge in men. No clinical symptoms were specifically diagnostic of MG infection in women.
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Raf-1 kinase activity predicts for paclitaxel resistance in TP53mut, but not TP53wt human ovarian cancer cells. Oncol Rep 2000; 7:821-5. [PMID: 10854551 DOI: 10.3892/or.7.4.821] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have recently reported that there is a significant Raf-1 kinase dependency of paclitaxel resistance in human cervical tumor cell lines. In light of the possibility that Raf-1 kinase inhibitors could be used to enhance paclitaxel responsiveness in ovarian cancer, we have characterized the Raf-1 kinase dependency of paclitaxel resistance in ovarian cancer cells. The relationship between Raf-1 kinase activity and the sensitivity to clinically relevant paclitaxel concentrations was determined in four ovarian cancer cell lines (CA-OV3, SK-OV3, 2780/WT and OAW42/WT). Furthermore, in recognition that such a drug combination would initially be used in patients whose tumors have recurred following cisplatin/paclitaxel treatment, we also determined the Raf-1 kinase dependency of paclitaxel cytotoxicity in cisplatin resistant variants of two of the ovarian cell lines (2780/CP and OAW42/CP). In the two cell lines (2780/WT and OAW42/WT) that possess a wild-type TP53 (TP53wt), the relationship between Raf-1 kinase activity and paclitaxel resistance was different from that observed in the cervical tumor cell lines. In these cell lines, paclitaxel-induced far more cell killing than would have been predicted from their Raf-1 kinase activity. However, in the ovarian cancer cell lines (CA-OV3, SK-OV3, 2780/CP and OAW42/CP) that have a mutant TP53 (TP53mut), the cytotoxicity induced by 60 nM paclitaxel exhibited the same relationship to Raf-1 kinase activity as previously observed in cervical tumor cell lines. These data suggest that the therapeutic efficacy of paclitaxel in ovarian cancer patient whose tumors have TP53mut might be increased if it is administered in combination with Raf-1 kinase inhibitors, e.g., ISIS 5132.
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Modification of non-conservative double-strand break (DSB) rejoining activity after the induction of cisplatin resistance in human tumour cells. Br J Cancer 1999; 79:843-9. [PMID: 10070879 PMCID: PMC2362674 DOI: 10.1038/sj.bjc.6690135] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The induction of collateral radioresistance after the development of cisplatin resistance is a well-documented phenomenon; however, the exact processes that are responsible for the cisplatin-induced radioresistance remain to be elucidated. There was no obvious difference in the level of radiation-induced DNA double strand breaks (DSBs), in DSB rejoining rates, or the level of the catalytic subunit of the DNA-dependent protein kinase (DNA-PKcs) in the cisplatin- and radiation-sensitive 2780/WT and cisplatin-resistant 2780/CP cell lines. However, there was a significantly (P < 0.01) lower level of DSB misrejoining activity within nuclear protein extracts derived from the cisplatin- and radiation-sensitive 2780/WT and OAW42/WT tumour cell lines than in similar extracts from their cisplatin- (and radiation-) resistant 2780/CP and OAW42/CP counterparts. All of the DSB misrejoining events involved deletions of between 134 and 444 bp that arose through illegitimate recombination at short repetitive sequences, such as those that arise through non-homologous repair (NHR). These data further support the notion that the radiosensitivity of DSB repair proficient human tumour cell lines may be partly determined by the predisposition of these cell lines to activate non-conservative DSB rejoining pathways. Furthermore, our data suggest that the induction of acquired cisplatin resistance is associated with a two- to threefold decrease in the activity of a non-conservative DSB rejoining mechanism that appears to be a manifestation of NHR.
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Paclitaxel is preferentially cytotoxic to human cervical tumor cells with low Raf-1 kinase activity: implications for paclitaxel-based chemoradiation regimens. Radiother Oncol 1998; 48:329-34. [PMID: 9925253 DOI: 10.1016/s0167-8140(98)00084-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND AND PURPOSE Low Raf- kinase activity has been reported to be associated with radioresistance in epithelial tumor cell lines and with paclitaxel sensitivity in cervical tumor cells. Paclitaxel might thus be effective in eliminating radioresistant clones from cervical tumors, even in the absence of synergistic interaction between these therapeutic modalities. We thus established the relationship between Raf-1 kinase activity and radiosensitivity in human cervical tumor cells and determined if paclitaxel is preferentially cytotoxic to radio-resistant tumor clones. MATERIALS AND METHODS We established and contrasted the radiation and paclitaxel sensitivity of 12 human cervical tumor clones that exhibited a wide range of Raf-1 kinase activity. RESULTS Raf-1 kinase activity was inversely correlated (P = 0.001) with SF2 values in the 12 cervical tumor clones studied. Paclitaxel was preferentially cytotoxic to radioresistant tumor clones, with the level of paclitaxel-induced cytotoxicity being significantly (P = 0.0016) influenced by Raf-1 kinase activity levels. CONCLUSIONS Our in vitro data indicate that there are marked, but completely opposite, Raf-1 kinase dependencies of radiation and paclitaxel cytotoxicity in cervical tumor cells. The use of combined paclitaxel and radiotherapy treatment may thus lead to higher local control rates for squamous cell carcinoma of the cervix. Circumstantially, our data suggest that the greatest therapeutic gains might accrue if paclitaxel was administered when there is the greatest proportion of tumor clones with low Raf-1 kinase activity. It may thus be desirable to use paclitaxel towards the end of radiotherapy treatment or post-radiotherapy as consolidation therapy.
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High Raf-1 kinase activity protects human tumor cells against paclitaxel-induced cytotoxicity. Clin Cancer Res 1998; 4:1111-6. [PMID: 9607567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Paclitaxel (Taxol) is becoming increasingly important in the treatment of many tumors, although a large proportion of tumors fail to respond to this drug. The identification of the processes that confer cellular paclitaxel resistance could provide potential targets for novel therapies that may help to eliminate paclitaxel-resistant tumors. Recent reports suggest that the Raf-1 protein kinase may have a profound influence on the level of paclitaxel-induced apoptosis. We have critically evaluated the relationship between Raf-1 kinase activity and de novo paclitaxel resistance in early-passage human cervical tumors. In the 12 cell lines studied, Raf-1 kinase activity was inversely correlated (P = 0.0016) with the level of cytotoxicity induced by 60 nM paclitaxel. The relationship between these two parameters seems to be more than an epiphenomenon, because genetic down-regulation of Raf-1 kinase activity led to an approximately 4-fold increase in paclitaxel-induced cytotoxicity. The data from both our transfection studies and those on the 12 unperturbed cell lines are consistent with Raf-1 kinase being a negative determinant of paclitaxel-induced cytotoxicity. Because the cytotoxicity of paclitaxel is primarily attributable to apoptosis, these data suggest that Raf-1 kinase acts to suppress paclitaxel-induced apoptosis. These data suggest that the clinical effectiveness of paclitaxel could be substantially improved by the use of Raf-1 kinase inhibitors, provided that a similar relationship between Raf-1 kinase activity and paclitaxel cytotoxicity exists in the clinic, especially in those tumor sites where paclitaxel is the current treatment of choice e.g., ovarian and breast cancer.
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Infants at risk for schizophrenia: sequelae of a genetic neurointegrative defect. A review and replication analysis of pandysmaturation in the Jerusalem Infant Development Study. ARCHIVES OF GENERAL PSYCHIATRY 1992; 49:221-35. [PMID: 1373598 DOI: 10.1001/archpsyc.1992.01820030053007] [Citation(s) in RCA: 246] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A 1975 report stated that a schizophrenic genotype may be manifested in infants by a neurointegrative defect called pandysmaturation. Recent evidence supports this: (1) 12 studies found delayed development in schizophrenics' infants and in preschizophrenics; (2) "blind" psychometric evaluations favored an adult schizotypal disorder in four to six of seven high-risk subjects with pandysmaturation in the New York study; and (3) finally, in a partial replication of this method using the Jerusalem data, blind diagnoses of "probable" and "possible" pandysmaturation were significantly related to a parental diagnosis of schizophrenia and to cognitive and motor neurointegrative deficits at 10 years. Obstetrical complications were unrelated to diagnosis, pandysmaturation, or outcome in the overall sample. However, we found a small subgroup of schizophrenic offspring in whom the most severe motor deficits at follow-up were related to obstetrical complications, pandysmaturation, and low birth weight.
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Abstract
The Kiddie Formal Thought Disorder Rating Scale (K-FTDS) was examined in a sample of 29 schizophrenic, 10 schizotypal, and 54 normal children, aged 5-12.5 yrs. The schizophrenic and schizotypal children had significantly more illogical thinking and loose associations than the normal children. There were no significant differences between the illogical thinking and loose associations ratings of the schizophrenic and schizotypal children. Young schizophrenic, schizotypal, and normal children had more illogical thinking and loose associations than older children in their respective groups. The diagnostic, developmental, and cognitive implications of the study's results are discussed.
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Abstract
This study seeks relationships between the degree of dendrite complexity of four areas of the human cerebral cortex and the type of function subserved by those areas. Quantitative studies of basilar dendrite patterns in the trunk and hand-finger receptive zones of areas 3 and 1, superior gyrus of the prefrontal cortex (area 9), and supramarginal gyrus (area 39) of the parietal lobe, in the left hemisphere of 10 subjects are reported. Measurements of dendrite complexity were based on the Sholl method of counting dendrite intersections with a series of superimposed concentric rings centered on the middle of the neuron soma. The data were analyzed graphically to show (1) characteristic dendrite profiles generated by cells in each of these areas, (2) comparisons between dendrite systems of two paired areas, i.e., trunk vs. hand-finger, and hand-finger vs. supramarginal, and (3) cumulative dendrite-ring intersection patterns for all areas studied. The data provided only partial support for our working hypothesis suggesting a relationship between complexity of the dendrite arbor and the nature of the computational tasks performed by the area. However, complexity of dendrite systems in the trunk area was found to be generally less than that of any other. In addition, there were suggestive associations between the complexity of dendrite systems of the hand-finger zone of the primary sensory receptive area and the nature of the work with which the individual had been associated during his/her working life. It proved more difficult to discern relationships between structure and function in the cortical associative areas. The study underlines the large degree of interindividual variation in dendrite structure and the need for much more extensive information about the life history of individuals who serve as subjects for this type of study.
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Childhood-onset depressive disorders. A follow-up study of rates of rehospitalization and out-of-home placement among child psychiatric inpatients. J Affect Disord 1988; 15:245-53. [PMID: 2975297 DOI: 10.1016/0165-0327(88)90022-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
This report describes preliminary outcome data for a sample of child psychiatric inpatients with diagnoses of major depression and/or dysthymic disorder at the time of their hospitalizations. Depressed children were compared with a contrast group of children with schizophrenia spectrum disorders. Results (based on semi-structured telephone interviews) indicate high rates of rehospitalization among our depressed cohort. Depressed children had rehospitalization rates of 35% and 45% respectively in the first and second years after discharge. Out-of-home placement was rarer in the depressed group, and significantly less likely than for children with schizophrenia spectrum disorders. However, 15% of the depressed cohort were placed out of their homes within the first year of discharge. There were no differences between children with major depressive and dysthymic disorders on these outcome variables, underscoring the serious long-term correlates of childhood dysthymic as well as major depressive disorders.
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Abstract
80.2 Per cent of 111 Down syndrome pregnancies had anmiotic fluid (AF) alpha fetoprotein (AFP) levels on or below the median and 10.8 per cent at or below 0.5 MoM compared with 41.9 and 1.4 per cent of controls. These differences were even more striking when the gestational age was less than 18 weeks compared with greater than or equal to 18 weeks. No such association was seen for other chromosome abnormalities including trisomy 18,45,X and mosaics, 47,XXY,47,XXX, and other structural abnormalities and triploidy, even when high levels due to defects such as omphalocele and cystic hygroma were excluded. All cases of trisomy 13 and 80 per cent with 47,XYY had AF-AFP levels above the median. Selection of cases for karyotyping by a low level of AF-AFP would clearly fail to detect aneuploidies other than Down syndrome and is not recommended. A possible weak association between low maternal serum (MS) and AF-AFPs in Down syndrome was most evident at less than 18 weeks, suggesting that MS screening between 16 and 18 weeks may be the most informative time.
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Application of meta-analysis using an electronic spread sheet to exercise testing in patients after myocardial infarction. Am J Med 1987; 83:1045-54. [PMID: 3332565 DOI: 10.1016/0002-9343(87)90940-5] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Decision analysis is being applied to medical practice in order to achieve cost efficacy in health care delivery. Critical to this process is establishing the diagnostic and prognostic accuracy of medical tests and the effectiveness of interventions. Meta-analysis is an approach that applies statistical methods to groups of studies in order to extract consensus results. Electronic spreadsheets facilitate meta-analysis with their ability to store, sort, graph, and mathematically manipulate both the methodologic approaches and clinical findings of seemingly disparate studies. As an example, this application is demonstrated with an analysis of studies that were performed to evaluate the prognostic value of exercise testing in patients recovering from a myocardial infarction. The following conclusions were reached: (1) patients excluded from exercise testing have the highest mortality; (2) only subsets of patients have been tested resulting in highly selected patient samples that make findings difficult to generalize; (3) of the five exercise test responses, only an abnormal systolic blood pressure response and a poor exercise capacity predicted risk more frequently than by chance; (4) submaximal or predischarge testing has greater predictive power than postdischarge or maximal testing; and (5) exercise-induced ST segment depression only appears to be predictive of increased risk in patients with inferior-posterior myocardial infarctions. This approach to combining studies is important since even careful analysis of a single study cannot elucidate all of the complex interactions and selective biases that have occurred. However, comparison of many heterogeneous studies is at best an arduous and time-consuming task. This approach to using electronic spreadsheets to collate and analyze multiple studies facilitates recognition of the population characteristics, clinical factors, and methodologic considerations that affect outcome and allows the quick inclusion of additional studies for re-analysis and interpretation.
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Combining maternal age and serum alpha-fetoprotein to predict the risk of Down syndrome. Obstet Gynecol 1986; 68:177-80. [PMID: 2426637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Twenty-eight cases of Down syndrome with maternal serum alpha-fetoprotein (AFP) measured at second trimester were added to 137 previously reported cases. Seventy-eight percent of affected pregnancies had levels at or below the median AFP value, compared with 50% of unaffected pregnancies. Maternal age at delivery and serum AFP levels by multiples of the median were used to construct a table to determine the risk of Down syndrome. This was compared with the risk for a 35-year-old woman (one in 365). Similar risks were estimated for a 21-year-old with AFP below 0.4 multiples of the median, a 23-year-old below 0.5, a 26-year-old below 0.6, and a 29-year-old below 0.7 multiples of the median. This study provides guidelines for counseling pregnant women who have low serum AFP levels.
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Abstract
Platelet monoamine oxidase (MAO) activity was studied in 22 boys diagnosed as having attention deficit disorder with hyperactivity and 12 healthy control boys admitted to a clinical research center and placed on a diet low in monoamines. The hyperactive boys had lower platelet MAO activity than controls, and MAO activity was related to performance on the Matching Familiar Figures Test (MFF) and the Continuous Performance Test (CPT), which yield scores sensitive to impulsivity and inattention. Furthermore, it was negatively related, in hyperactive boys only, to two tests of reading and spelling achievement. Administration of d-amphetamine and placebo in a double-blind crossover design did not significantly raise MAO levels above baseline and was minimally related to improved performance on the MFF and CPT.
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Abstract
Glomerulonephritis patients transplanted with cadaver kidneys had a significantly higher one-year graft survival when immunosuppressed with cyclosporin rather than standard therapy (80% versus 59%, p less than 10(-5]. For nephrosclerosis patients the corresponding rates were 70% and 59% (p greater than 0.05); and in those with antecedent diabetes mellitus, polycystic kidney, and pyelonephritis the differences were negligible. In glomerulonephritis patients, but not in the other groups, cyclosporin was additive to the effect of transfusions and of HLA-A, B and HLA-Dr matching.
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Abstract
The one-year kidney transplant survival rates from parental donors into recipients with pyelonephritis (PN) was 79% as compared with the low rate of 62% for polycystic disease (PC) and diabetes mellitus (DM). Even more striking was the 42% one-year graft survival in systemic lupus erythematosus (SLE) patients receiving parental donor grafts. HLA-identical sibling donor transplants into patients with DM had a low survival rate of 75% as compared with 90% in PN patients. These results were analyzed for interactions of donor type and disease by comparing the relative survival rates among types of donors within each recipient disease. After taking into account higher overall risks attributable to medical complications inherent in the different disease categories, related donor grafts into patients with PC, SLE, and DM have lower graft survival rates than would be expected from differences in cadaver donor rates by disease. In practical terms, for related donor transplants into patients with SLE, DM, and PC, it may be necessary to consider the vulnerability of the donor organ as another factor.
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Significant HLA and erythrocyte phenotypes among physicians, nurses and medical technologists ("genes of a feather flock together"). JOURNAL OF THE MEDICAL ASSOCIATION OF THE STATE OF ALABAMA 1983; 52:29-30. [PMID: 6833906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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HLA-DR3 associated with improved kidney transplant survival. Transplant Proc 1982; 14:308-10. [PMID: 7051472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Using the National Kidney Recipient Pool and selecting all patients who were HLA-DR typed, immunized by either transfusion or kidney allograft, and had recorded cytotoxic antibody against a panel of lymphocytes, we found significantly lower levels of cytotoxic antibody in patients with HLA-DR3 (p less than 0.05). Moreover, when we examined patients with only HLA-DR3 (presumed homozygous) we found that the low response effect was even stronger and was significant at 30%, 67%, or 90% cytotoxic antibody cutoffs. One of the immediate predictions of postulating that homozygous HLA-DR3 patients are low responders is that these patients should have better kidney transplant survival. Indeed, when we examined transplant survival in HLA-DR3 homozygous transplant patients and non-HLA-DR3 patients, the 1-year survival was 74% +/- 9% vs. 49 +/- 4%, respectively. When one stratifies the data for transfusion effect, the 0-4 transfusion category shows 43% +/- 5% survival for non-HLA-DR3 recipients vs. 79% +/- 10% for HLA-DR3 only recipients. These data strongly suggest HLA-DR3 individuals have a low responsiveness to histocompatibility antigens.
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Reduction of accelerated failures by transfusion. Transplant Proc 1982; 14:251-9. [PMID: 7051463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Offspring to mother kidney transplants. An example of donor-specific immunized transplants. Transplantation 1982; 33:450-2. [PMID: 7041372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Abstract
T, B, and null lymphocytes isolated by sheep red blood cells (SRBC) rosetting or adherence to a nylon wool column had distinct size differences according to Coulter counter size analysis. The diameters in microns were as follows: B = 6.42, T = 6.76, null = 7.16, granulocytes = 8.42, and monocytes = 9.02. Coulter size distributions of cell preparations were compared to the proportions of cells with E, EAC, and surface immunoglobulin (SIg) markers in these preparations as well as their reactivity to HLA--DR antisera and rabbit anti-B-lymphocyte antisera. Cell preparations monitored by Coulter sizing produced the expected results in mixed lymphocyte culture (MLC) testing. That is, T cells responded but did not stimulate whereas B lymphocytes and monocytes stimulated but did not respond. NULL lymphocytes both stimulated and responded. In antibody-dependent cell-mediated cytotoxicity (ADCC), null lymphocytes and monocytes functioned as effectors, whereas T lymphocytes and granulocytes did not. B lymphocyte preparations were intermediate in activity. Coulter sizing is a rapid, simple means of assessing the purity of suspensions enriched for T, B, and null lymphocytes.
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International cell exchange. Transplant Proc 1978; 10:717-20. [PMID: 83703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Abstract
Using HLA tissue typing as the basic genetic test along with ABO and haptoglobin typing, it is generally possible either to exclude a putative father conclusively or, in nonexclusion cases, to assign a greater than 95% probability of paternity. In 22 of 53 nonexclusion cases, the putative father had a probability of paternity above 99% based on these genetic tests.
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Abstract
The overall error rate of the microlymphocytotoxicity test has been reduced from 1.08% in 1971 to approximately 0.35%, based on comparisons of 882 replicate test pairs (different bleedings) and on family studies, with 0.11% attributable to "reading" errors. This reduction was attributed to automation for lymphocyte adding, better incubation temperature control, better technical preparation of cells and stronger, more monospecific sera. Three types of errors contribute to the overall error rate: random, sera-related (affected by strength and specificity), and lymphocyte-related (possible B-cell reactivity and donor/lymphocyte physiological condition). Strongly skewed error distributions, which seem to be lymphocyte-related, occurred in less than 4% of the test pairs.
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Abstract
The photochemistry done by single chloroplasts can be measured when the chloroplasts are embedded in nuclear track emulsion. It has been known for more than 50 years that certain chemicals will blacken photographic plates (chemical fogging). Although this effect has been little used to measure chemical reactions, it may be particulary useful in photochemistry and electrochemistry, since as little as 10(-18) mole can be measured.
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