401
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Shoji Y, Akhtar S, Periasamy A, Herman B, Juliano RL. Mechanism of cellular uptake of modified oligodeoxynucleotides containing methylphosphonate linkages. Nucleic Acids Res 1991; 19:5543-50. [PMID: 1658734 PMCID: PMC328955 DOI: 10.1093/nar/19.20.5543] [Citation(s) in RCA: 147] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The cellular uptake and intracellular distribution of methylphosphonate oligonucleotides (15 mers) has been examined using both 32P labeled and fluorescent labeled oligonucleotides. The cellular uptake process for methylphosphonate oligonucleotides is highly temperature dependent, with a major increase in uptake occurring between 15 and 20 degrees C. Most of the label which becomes cell associated at 37 degrees C cannot be removed by acid washing or trypsinization and thus seems to be within the cell. Visualization of rhodamine labeled methylphosphonate oligonucleotides using digital imaging fluorescence microscopy reveals a vesicular subcellular distribution suggestive of an endosomal localization. There was extensive co-localization of rhodamine labeled methylphosphonate oligonucleotides with fluorescein-dextran, an endosomal/lysosomal marker substance. The apparent endocytotic uptake of labeled methylphosphonate oligonucleotides could not be blocked by competition with unlabeled methylphosphonate or phosphodiester oligonucleotides, nor by ATP. This contrasts with the situation for radiolabeled phosphodiester oligonucleotides whose uptake can be completely blocked with unlabeled competitor. Uptake of phosphodiester oligonucleotides, but not of methylphosphonate oligonucleotides, could be blocked by acidification of the cytosol. These observations suggest that the pathway of cellular uptake of methylphosphonate oligonucleotides involves fluid phase or adsorbtive endocytosis, and is distinct from the uptake pathway for phosphodiester oligonucleotides.
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402
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Mehmood A, Akhtar S, Ullah N, Khan MI. The use of the probit model to predict pregnancy status of buffalo based on physio-chemical properties of estrual mucus. Theriogenology 1991; 36:117-22. [PMID: 16726984 DOI: 10.1016/0093-691x(91)90440-o] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/1990] [Accepted: 05/24/1991] [Indexed: 11/20/2022]
Abstract
Improper timing of artificial insemination with respect to ovulation is one of the major factors hampering the conception rate in buffalo. The present study was an attempt to relate physio-chemical changes in estrual mucus to subsequent pregnancy status in order to find their optimal values for determining the time for artificial insemination (AI). Serum estradiol, total protein and dry matter contents of estrual mucus were evaluated to predict the subsequent pregnancy in 36 buffalo during October 1988 to February 1989. Serum estradiol was determined by radioimmunoassay (RIA); spinnbarkeit, dry matter and total protein were determined by standard methods. Multivariate probit analyses were carried out to relate these variables to subsequent pregnancy status. Elasticity and protein concentration were significantly related to prediction probability of pregnancy status, and they predicted the pregnancy status 86% of the times correctly (P<0.05). The probability of pregnant animals being correctly classified was 0.76, whereas the corresponding value for non-pregnant animals was 0.95. The present study demonstrated the possibility of using such a statistical model on mucus characteristics for determining proper AI time for better conception rates in Nili-Ravi water buffalo.
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403
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Akhtar S, Kole R, Juliano RL. Stability of antisense DNA oligodeoxynucleotide analogs in cellular extracts and sera. Life Sci 1991; 49:1793-801. [PMID: 1943483 DOI: 10.1016/0024-3205(91)90480-y] [Citation(s) in RCA: 176] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Antisense DNA oligodeoxynucleotides can selectively inhibit the expression of individual (undesirable) genes and thus, have potential in the treatment of cancer and viral diseases. A prerequisite to their use as therapeutic agents is information on the stability of oligodeoxynucleotides, and their structurally modified analogs, in the biological milieu. To this end, degradation of 5' end and internally [32P] labelled unmodified DNA oligodeoxynucleotide (D-oligo) and analogs containing phosphorothioate (S-oligo), methylphosphonate (MP-oligo), and novel alternating methylphosphonate and phosphodiester (Alt-MP-oligo) internucleoside linkages was studied in Hela cell nuclear extract, S100 cytoplasmic extract, normal human serum and calf serum at 37 degrees C. Both 5' end and internally labelled D-oligos showed complete degradation within 30 min incubation in human serum at 37 degrees C. In any given medium, the D-oligo was the least stable oligodeoxynucleotide to nuclease degradation whereas the Alt-MP, MP and S-oligos were generally of comparable stability and all relatively more stable than D-oligo. Interestingly, MP and Alt-MP-oligos also exhibited greater resistance to phosphatases in cellular extracts compared to D and S-oligos. Under the conditions of the experiments, increasing degradation for any given oligonucleotide was observed in the order: S100 cytoplasmic extract less than nuclear extract less than normal human serum less than calf serum. In a study involving alpha-MEM cell culture medium containing 10% heat inactivated fetal calf serum (heated to 56 degrees C for 1 hour), the D-oligo was found to be rapidly degraded (degradation evident within 10 mins) whereas degradation products for the S-oligo were observed within 1 hour. In contrast, the Alt-MP oligo remained stable throughout the 3 hour experiment. These results indicated that in cell culture medium containing heat inactivated serum Alt-MP oligo was more stable than D- and S-oligos.
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404
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Ahmad T, Akhtar S, Haider S. A study on stability of mestranol. PAKISTAN JOURNAL OF PHARMACEUTICAL SCIENCES 1991; 4:63-70. [PMID: 16414683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Mestranol, a synthetic oestrogcn, is an oral contraceptive given alongwith progestogens. It is light, heat and air sensitive and on uv irradiation new polymeric species of glucosiduronate and sulphate conjugate are formed. The new species fractions of mestranol are separatable over sephadex in column chromatography and characterized by analytical techniques employed in this investigation. This investigation is aimed to study formation of these species quantitatively for stability induced formulations.
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405
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Akhtar S, Afzal M, Ali S, Khan MI. Effect of reactor retention on the spread of brucellosis in Jersey cattle and buffalo herds. REV SCI TECH OIE 1990; 9:1179-85. [PMID: 2132710 DOI: 10.20506/rst.9.4.536] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The rate of spread of bovine brucellosis was investigated in buffalo and Jersey cattle herds maintained at a Livestock Research station in Pakistan. Reactor animals (identified by conventional serological tests) were either retained or culled because of advanced age or poor productivity. Reactors were housed, managed and fed separately from the rest of the herds. The initial seroprevalence of brucellosis among both the Jersey cattle and the buffalo tested was 21.4%, the difference being statistically insignificant (p = 0.218). For 34 months, the spread of brucellosis was limited to 25 new reactors in the 334 cows and 33 in the 442 buffaloes. The mean attack rate was 7.5% for both herds during the test intervals. Trend analysis of proportions positive at each testing revealed a significant decrease in the percentages observed at the first testing. The management practice of segregation offered some advantage in reducing the spread of brucellosis to negative animals. However, an epidemiological study covering a large number of herds would be required to identify risk factors responsible for perpetuating the disease.
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406
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Akhtar S, Riemann HP, Thurmond MC, Farver TB, Franti CE. The use of loglinear model to evaluate factors associated with sero-prevalence of Campylobacter fetus in dairy cattle. Theriogenology 1990; 34:989-1001. [PMID: 16726898 DOI: 10.1016/0093-691x(90)90567-d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/1989] [Accepted: 09/11/1990] [Indexed: 11/21/2022]
Abstract
Campylobacter fetus is one of the leading infections causing bovine infertility and abortion. In a cross-sectional study, the associations of parity, herd, serological status against Leptospira hardjo and Haemophilus somnus with the sero-prevalence of Campylobacter fetus in dairy cattle were evaluated. Four hundred dairy cows from three herds were included in the study. Blood samples from the cows were collected in December 1986. An enzyme-linked immunosorbant assay (ELISA) was used to determine positive or negative status of cows against Campylobacter fetus , Haemophilus somnus and Leptospira hardjo antigens. Loglinear analysis was used to describe the relationship of four categorical variables with the sero-prevalence of Campylobacter fetus . The final loglinear model was interpreted as a logit model. The final loglinear model included a three-way interaction among Campylobacter fetus , Leptospira hardjo and herd and a two-way interaction between Campylobacter fetus and parity. The adjusted odds of being a positive Campylobacter fetus reading were highest for cows with parity >6 (e.g. 27.8, 95% confidence interval (CI) = 12.9, 60.1); it was next highest for cows in parity <4 (e.g. 18.0, 95% CI = 13.5, 24.2); and it was lowest for cows in parity 4 to 6 (e.g. 13.3, 95% CI 7.3, 24.4). The herd management practice that was associated with the carrier state in early and late parities is identified in the study, and the biological implication of a three-way interaction among Campylobacter fetus , Leptospira hardjo and herd are discussed.
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407
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Davies MC, Khan MA, Short RD, Akhtar S, Pouton C, Watts JF. XPS and SSIMS analysis of the surface chemical structure of poly(caprolactone) and poly(beta-hydroxybutyrate-beta-hydroxyvalerate) copolymers. Biomaterials 1990; 11:228-34. [PMID: 2383617 DOI: 10.1016/0142-9612(90)90002-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The surface chemical structures of poly(beta-hydroxybutyrate), poly(caprolactone) and poly(beta-hydroxybutyrate-co-beta-hydroxyvalerate) have been analysed using static secondary ion mass spectrometry and X-ray photoelectron spectroscopy. The X-ray photoelectron spectroscopy data confirm the purity of the polyester surfaces and there is close agreement between the stoichiometric and experimentally determined ratios of the peaks and different carbon environments within the C1s envelopes. The static secondary ion mass spectrometry analysis reveals general fragmentation pathways which permit the ready distinction between the different polyesters examined. The differentiation of the different monomer repeat units in the copolymer together with the detection of some ions representative of the random copolymer sequence are also possible in the static secondary ion mass spectrometry analysis.
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408
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Akhtar S. Concept of interpersonal distance in borderline personality disorder. Am J Psychiatry 1990; 147:260-1. [PMID: 2328058 DOI: 10.1176/ajp.147.2.260b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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409
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Akhtar S, Verma SM, Verma SH. Asneezia. Br J Psychiatry 1990; 156:285. [PMID: 2317638 DOI: 10.1192/bjp.156.2.285b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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410
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Abstract
Suspiciousness, feeling persecuted, and grandiosity constitute the classical triad associated with paranoid personality. However, a more important feature appears to be the discrepancy between the outer persona and the inner world of such individuals. The split is pervasive and involves self-concept, object-relations, affects, morality, sexuality, and cognitive style. Outwardly, paranoid individuals are demanding, arrogant, mistrustful, driven, unromantic, moralistic, and acutely vigilant towards the external environment. Internally, however, they are frightened, timid, self-doubting, gullible, inconsiderate, vulnerable to erotomania, and cognitively unable to grasp the totality of actual events. This way of conceptualizing the paranoid symptomatology is superior to ordinary check-list methods since it (1) links the phenomenological and psychostructural aspects of the condition, (2) helps in a more meaningful differential diagnosis of paranoid from other personality disorders, and most importantly, (3) hints at areas that require exploration in the psychotherapeutic management or psychoanalysis of such individuals.
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411
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Gorton G, Akhtar S. The literature on personality disorders, 1985-88: trends, issues, and controversies. HOSPITAL & COMMUNITY PSYCHIATRY 1990; 41:39-51. [PMID: 2403965 DOI: 10.1176/ps.41.1.39] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
This review of the recent literature on personality disorders summarizes theoretical and methodologic issues, DSM-III-R criteria sets, nosological controversies, and current treatment approaches. Work in the personality disorders is burgeoning, with increasing attention to improved reliability and validity of diagnosis. Investigators are looking at such issues as the development of dimensional taxonomies, the effect of state variables, the problem of diagnostic overlap, the effect of comorbid conditions on course and treatment, the predictive power of criteria, and external validators. The DSM-III-R criteria sets, despite their polythetic format, may be no more reliable than their predecessors. Because treatment remains largely unresearched, the clinician must continue to rely on skillful assessment of each patient, with psychoanalytic psychotherapy and symptom-oriented drug trials providing the foundation of therapy.
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412
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Akhtar S. Narcissistic personality disorder. Descriptive features and differential diagnosis. Psychiatr Clin North Am 1989; 12:505-29. [PMID: 2678019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
This article brings the scattered literature on narcissistic personality disorder together and synthesizes its various descriptive aspects into a multifaceted profile of the condition. The disorder is viewed as consisting of characteristic "overt" and "covert" findings in six areas of psychosocial functioning: (1) self-concept; (2) interpersonal relations; (3) social adaptation; (4) ethics, standards and ideals; (5) love and sexuality; and (6) cognitive style. Overtly, and individual with narcissistic personality disorder is grandiose, exploitative, moralistic, often successful, seductive, charming, and impressively knowledgeable and articulate. Covertly, however, he is doubt ridden, deeply envious of others, chronically bored, corruptible, unable to love, forgetful of details, and inattentive to objective aspects of events. Such conceptualization is superior to ordinary checklist methods of diagnosis, as it combines descriptive and psychodynamic observations and correlates the behavioral and psychostructural (hence developmental) aspects of the narcissistic character pathology. This profile also helps in more meaningful differential diagnosis of narcissistic from related personality disorders.
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413
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Kurian J, Akhtar S, Nando GB, De SK. Scanning electron microscopy studies on tensile failure of polyethylene-filled natural rubber vulcanizates. J Appl Polym Sci 1989. [DOI: 10.1002/app.1989.070370410] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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414
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Kramer S, Akhtar S. The developmental context of internalized preoedipal object relations. Clinical applications of Mahler's theory of symbiosis and separation-individuation. THE PSYCHOANALYTIC QUARTERLY 1988; 57:547-76. [PMID: 3212103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Mahler's theory of symbiosis and separation-individuation demonstrates the essential unity of drive, ego, and object relations psychologies. By highlighting the role that early dyadic relations play in psychic structure formation, her theory expands the understanding of human psychic development and its failures. This paper reviews Mahler's propositions and underscores their clinical importance by describing two cases where much preoedipal reconstructive work preceded the emergence of an analyzable oedipal transference neurosis.
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415
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Abstract
This paper describes four culture-bound psychiatric syndromes seen in India. It highlights their phenomenology and briefly comments upon the socio-cultural correlates of such symptom constellations.
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416
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Abstract
Various views of schizoid personality disorder in descriptive psychiatry, psychoanalysis, DSM-III and DSM-III-R are reviewed and synthesized to develop a composite picture of the syndrome. The disorder is seen as consisting of characteristic deficits in six areas of psychosocial functioning: (1) self-concept, (2) interpersonal relations, (3) social adaptation, (4) ethics, standards and ideals, (5) love and sexuality, and (6) cognitive style. Such a view maintains historical continuity in the use of the term "schizoid," combines descriptive and psychodynamic observations and correlates the behavioral and psychostructural aspects of the schizoid pathology. The paper also identifies guidelines for distinguishing the schizoid personality from other personality disorders as well as areas needing continued research.
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417
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Akhtar S, Bhagawan SS. Dynamic Mechanical Properties of NR-HDPE Blends. RUBBER CHEMISTRY AND TECHNOLOGY 1987. [DOI: 10.5254/1.3536143] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Abstract
Dynamic mechanical properties such as storage modulus, loss modulus, and loss tangent have been evaluated over a wide range of temperatures for thermoplastic elastomers prepared from blends of NR and HDPE. It was observed that above room temperature, both storage and loss moduli increased and loss tangent decreased as the HDPE content in the blend increased. The effects of dynamic crosslinking and carbon black filler on dynamic mechanical behavior of 70/30 NR/HDPE blend were also examined. Carbon black increased the storage and loss moduli but lowered and broadened the tan δ peak. On the other hand, crosslinking increased storage modulus and decreased the loss modulus and loss tangent, particularly after the NR Tg. The tan δ peak area which appeared at Tg for NR was proportional to the rubber content in the blends.
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418
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Akhtar S, Byrne JP, Doghramji K. The demographic profile of borderline personality disorder. J Clin Psychiatry 1986; 47:196-8. [PMID: 3957879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
In a survey of borderline personality disorder, 23 studies that included data on age, sex, or race of the patient samples were identified. Comparison of patients who had borderline personality disorder with control groups in these studies revealed that a significant preponderance of patients with the disorder were young, white, and female. This finding cannot be considered conclusive because data were pooled from studies with questionable sampling techniques. Yet, this demographic profile warrants confirmation because it may imply diagnostic biases or actual differences in the prevalence of borderline personality disorder among various groups.
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419
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Rashid F, Khan MM, Bari MA, Akhtar S, Ahmad S. Diarrhoea in children due to enterotoxigenic Escherichia coli. J PAK MED ASSOC 1986; 36:82-7. [PMID: 3090296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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420
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Abstract
The author delineates the syndrome of identity diffusion as consisting of six clinical features: 1) contradictory character traits, 2) temporal discontinuity in the self, 3) lack of authenticity, 4) feelings of emptiness, 5) gender dysphoria, and 6) inordinate ethnic and moral relativism. This syndrome implies severe character pathology and is distinct from adolescent identity crisis. The conceptualization has a significant bearing on the differential diagnosis and psychotherapy of personality disorders.
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421
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Akhtar S. "Digits forward"? J Clin Psychiatry 1983; 44:430. [PMID: 6643407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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422
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423
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Abstract
After briefly reviewing various contributions to the concept of splitting, the authors describe the clinical manifestations of this defense. These include 1) inability to experience ambivalence, 2) impaired decision making, 3) oscillation of self-esteem, 4) egosyntonic impulsivity, and 5) intensification of affects. The authors then discuss the relevance of such conceptualizations to the differential diagnosis and psychotherapy of personality disorders.
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424
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Abse DW, Rheuban WJ, Akhtar S. The poppy: therapeutic potential in cases of dementia with depression. Ann N Y Acad Sci 1982; 398:79-82. [PMID: 6961870 DOI: 10.1111/j.1749-6632.1982.tb39476.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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425
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Nawaz M, Akhtar S, Hashmi AS. Disposition kinetics and urinary excretion of sulphadimidine in normal and alloxan diabetic dogs. ACTA PHARMACOLOGICA ET TOXICOLOGICA 1982; 51:63-8. [PMID: 7124411 DOI: 10.1111/j.1600-0773.1982.tb01064.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Disposition kinetics and urinary excretion of sulphadimidine were investigated in 16 dogs following a single intravenous injection (100 mg/kg body weight). Biochemical parameters including blood pH, blood glucose, plasma triglycerides and total plasma proteins of these animals were determined. The animals were injected alloxan (125 mg/kg) intravenously and when blood glucose level exceeded 300 mg%, the biochemical parameters, disposition kinetics and urinary excretion of sulphadimidine were determined again. After alloxan treatment of the dogs, there was a highly significant (P less than 0.01) decrease in blood pH, increase in blood glucose and plasma triglycerides levels when compared with the pretreatment values. The alloxan diabetic dogs showed a highly significant (P less than 0.01) reduction in elimination half-life (t1/2 beta) and apparent volume of distribution (Vd(area)) and increase in overall elimination rate constant (kel), total body clearance (ClB) and percentage of sulphadimidine dose excreted in urine. In normal dogs, one-half of the intravenous dose and after alloxan treatment two-third of the dose was eliminated through urinary excretion during 48 hours after injection. This study shows that the metabolic alterations of alloxan induced diabetes in dogs, influence the drug disposition and urinary excretion which indicate the need for the adjustment of dosage regimen in such metabolic disorders.
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