1801
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Laconi E, Li F, Semple E, Rao PM, Rajalakshmi S, Sarma DS. Inhibition of DNA synthesis in primary cultures of hepatocytes by orotic acid. Carcinogenesis 1988; 9:675-7. [PMID: 3258555 DOI: 10.1093/carcin/9.4.675] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Orotic acid has been shown to promote carcinogenesis in the liver and the intestine of the rat. In an attempt to determine whether orotic acid promotes liver carcinogenesis by creating differential mitoinhibition, experiments were designed to study the effect of orotic acid on the labeling index of isolated hepatocytes in response to epidermal growth factor. The results indicated that orotic acid added in vitro inhibited epidermal-growth-factor-induced labeling index of isolated hepatocytes. In addition, isolated hepatocytes from rats exposed to orotic acid under promoting conditions also exhibited a decreased response to epidermal growth factor. These data suggest that orotic acid may exert its promoting effect by differentially inhibiting the response of normal hepatocytes to one or more endogenous growth stimuli while permitting the initiated hepatocytes to respond to such stimuli and grow to form hepatic nodules.
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1802
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McCrady CW, Li F, Grant AJ, Merchant RE, Carchman RA. Alteration of human lymphokine-activated killer cell activity by manipulation of protein kinase C and cytosolic Ca2+. Cancer Res 1988; 48:635-40. [PMID: 3257170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We have examined the effects of protein kinase C (PK-C) stimulation and cytosolic Ca2+ elevation on the in vitro induction of non-histocompatibility-restricted tumoricidal activity from human peripheral blood lymphocytes. The tumor cytolytic activity, as well as the number of cells recovered from interleukin 2 (IL-2)-stimulated cultures, was enhanced by the addition of the PK-C stimulator, phorbol dibutyrate (PDBu), but not non-PK-C-activating phorbol ester analogues while the Ca2+ ionophore, ionomycin, did not significantly alter development of IL-2-induced tumor cytolytic activity nor enhance cell yield. Neither PDBu nor ionomycin, alone or in combination, induced tumoricidal activity. The addition of both PDBu and ionomycin to recombinant interleukin 2 (rIL-2)-exposed cultures produced a strong mitogenic response and high cell yield, although Daudi cell killing measured at Day 5 was completely abolished. This abrogation of lymphokine-activated killer cell activity was seen as early as 24 h following exposure to PDBu and ionomycin, reaching 50% following 2 days of exposure. When lymphocytes mitogenically expanded by primary exposure to PDBu and ionomycin and then washed free of these agents were further cultured with rIL-2 alone, proliferation continued, and substantial cytolytic activity for Daudi cells was induced. The development of this postexpansion cytotoxic activity was not dependent on the addition of exogenous rIL-2 during the primary cultures. Fractionation of cells into large granular lymphocytes and small T-lymphocytes indicated that only the large granular lymphocytes proliferate in response to rIL-2 alone. Both large granular lymphocytes and small T-lymphocytes proliferate in response to the addition of PDBu and ionomycin, and both populations of cells developed tumor cytolytic activity following removal of PDBu and ionomycin and subsequent culture in rIL-2. These data suggest that PK-C and Ca2+ signals play key roles in the regulation and/or proliferation of tumor cytotoxic lymphocytes or their precursors and that manipulation of those signals can be utilized to produce substantially more tumoricidal activity from lymphocyte populations than can be achieved with rIL-2 alone.
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1803
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Liu JC, Tian Y, Qiu FX, Li F, Hao YP, Zhang XS. Serotyping and subgrouping of some rotavirus strains in China. J Med Virol 1987; 23:175-7. [PMID: 2824683 DOI: 10.1002/jmv.1890230210] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
This article reports for the first time in China the results of serotyping and subgrouping of some rotavirus strains obtained from faecal fluids of cases with infant diarrhoea. Infant diarrhoea rotavirus serotype 1 (Wa strain)-specific and serotype 2 (KUN strain)-specific hyperimmune sera, and infant diarrhoea rotavirus serotype 3-specific, rotavirus subgroup I-specific and subgroup II-specific monoclonal antibodies were used in serotyping and subgrouping by means of enzyme-linked immunosorbent assay of 14 rotavirus strains which had been identified by electron microscopy. Results showed that three out of four Beijing strains in 1982 belonged to serotype 2 and subgroup I rotavirus, one belonged to serotype 3 and subgroup II rotavirus; one out of nine Beijing strains in 1984 belonged to serotype 1 and subgroup II rotavirus, seven belonged to serotype 2 and subgroup I rotavirus, one belonged to serotype 3 and subgroup II rotavirus; and one Kunming strain in 1984 belonged to serotype 3 and subgroup II rotavirus.
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1804
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Lim CK, Li F, Peters TJ. High-performance liquid chromatography of type-III heptocarboxylic porphyrinogen isomers. Biochem J 1987; 247:229-32. [PMID: 3689347 PMCID: PMC1148392 DOI: 10.1042/bj2470229] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A reversed-phase h.p.l.c. system is described for the separation of the four type-III heptacarboxylic porphyrinogen isomers. The effects of buffer concentration, pH and type and proportion of organic modifier in the mobile phase on retention and resolution of isomers were studied. Optimum separation on an ODS-Hypersil column was by elution with a ternary mobile phase of acetonitrile, methanol and 1 M-ammonium acetate, pH 5.16 (7:3:90, by vol.). Isomer identification was based on a comparison of their retention times with those of authentic standards, and was further confirmed by h.p.l.c. analysis of the characteristic mixture of three pentacarboxylic porphyrins formed after partial decarboxylation of individual isomers in 0.3 M-HCl at 160 degrees C.
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1805
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Xiong HC, Qiu DG, Wang JR, Liu L, Tan MZ, Yang AL, Li F, Cao ZL, Sun WG. [Chronic type B hepatitis with delta factor infection]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 1987; 18:230-3. [PMID: 3679173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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1806
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Li F, Lim CK, Peters TJ. An h.p.l.c. assay for protoporphyrinogen oxidase activity in rat liver. Biochem J 1987; 243:863-6. [PMID: 3663105 PMCID: PMC1147937 DOI: 10.1042/bj2430863] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
An h.p.l.c. method is described for the assay of protoporphyrinogen oxidase activity in rat liver. A relatively pure protoporphyrinogen IX substrate was obtained by selectively removing any protoporphyrin IX unreduced by sodium amalgam on a small disposable cartridge packed with a strong anion-exchanger. The protoporphyrin IX formed was extracted with dimethyl sulphoxide/methanol (3:7, v/v) containing mesoporphyrin as the internal standard for separation and quantification by reversed-phase chromatography. The Km for protoporphyrinogen was 9.5 +/- 1.6 microM, and the enzyme activities were 0.59 +/- 0.11 nmol of protoporphyrin IX produced/min per mg of mitochondrial protein and 33.5 +/- 2.7 nmol protoporphyrin IX produced/min per g of liver tissue homogenate. The method is applicable to the determination of enzyme activity in small amounts of human liver biopsy.
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1807
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Li F, Lim CK, Peters TJ. Separation and characterization of pentacarboxylic porphyrinogen isomers by high-performance liquid chromatography with electrochemical detection. Biochem J 1987; 243:621-3. [PMID: 3632640 PMCID: PMC1147900 DOI: 10.1042/bj2430621] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A reversed-phase h.p.l.c. system is described for the separation of all five naturally occurring pentacarboxylic porphyrinogen isomers. The compounds are detected electrochemically with high sensitivity. The peaks are positively identified by h.p.l.c. analysis of the pentacarboxylic porphyrinogens from reduction of pentacarboxylic porphyrins prepared by partial decarboxylation of hexa- and hepta-carboxylic porphyrin III of known structures. The resolution of pentacarboxylic porphyrinogens is superior to that of the porphyrins and the method is applicable to the small-scale preparative isolation of pure isomers.
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1808
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Li F, Zhang MZ, Lu LT. [An evaluation of traumatic renal lesions with ultrasonography]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 1987; 25:231-2, 254-5. [PMID: 3308367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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1809
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Li F, Qin J, Liu Z, Wu Z, Qian B. Compatibility and Water Retentive Properties of Polyacrylonitrile Copolymer and Polyvinyl Acetate Copolymer Blend Fibers. JOURNAL OF POLYMER ENGINEERING 1987. [DOI: 10.1515/polyeng.1987.7.2.113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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1810
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Lim CK, Li F, Rideout JM, Wright DJ, Peters TJ. Assaying erythrocyte haem biosynthetic enzyme activities by high-performance liquid chromatography with the advanced automated sample processor. J Chromatogr A 1986; 371:293-8. [PMID: 3558550 DOI: 10.1016/s0021-9673(01)94713-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The four cytosolic haem biosynthetic enzymes in erythrocytes were assayed with the Varian advanced automated sample processor (AASP) for rapid sample concentration and clean-up with fast and effective high-performance liquid chromatography systems for separation and quantitation. In the assay for 5-aminolaevulinic acid dehydrase, the porphobilinogen (PBG) formed was extracted on a C18 AASP cartridge and separated by reversed-phase ion-pair chromatography with 32% methanol in 0.05 M sodium acetate buffer (pH 3.5), containing 5.4 mM of 1-heptane-sulphonic acid as eluent. PBG was the substrate for the simultaneous assay of hydroxymethylbilane synthase and uroporphyrinogen III synthase. The uroporphyrinogen I and III isomers formed were oxidised to porphyrins, concentrated on a C2 or C8 cartridge, and separated by reversed-phase chromatography with 13% acetonitrile in 1 M ammonium acetate buffer (pH 5.16) as eluent. Uroporphyrinogen decarboxylase was estimated with pentacarboxylic porphyrinogen III as substrate. The coproporphyrinogen formed was extracted on a C2 or C8 cartridge, oxidised to coproporphyrin and separated by reversed-phase chromatography with 30% acetonitrile in 1 M ammonium acetate buffer (pH 5.16) as mobile phase.
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1811
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Harris P, Morton CC, Guglielmi P, Li F, Kelly K, Latt SA. Mapping by chromosome sorting of several gene probes, including c-myc, to the derivative chromosomes of a 3;8 translocation associated with familial renal cancer. CYTOMETRY 1986; 7:589-94. [PMID: 3536362 DOI: 10.1002/cyto.990070614] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In eight members of a single family a constitutional translocation t(3;8) (p14.2;q24.1) is associated with the development of renal cancer. Chromosomes isolated from a cell line established from a subject with this translocation were analysed in flow with a fluorescence-activated cell sorter (FACS II). Nearly six million chromosomes from the flow karyotype region containing the der(8) and 5.5 million from the region containing the der(3) were sorted, the DNA extracted, digested with EcoRI, size fractionated by electrophoresis, and transferred to nitrocellulose. Hybridization with gene probes for c-mos, which has been localized to 8q11-q22 and somatostatin, which has been mapped to 3q28, confirmed that the sorted fractions contained, respectively, the der(8) and der(3) chromosomes. The cellular oncogenes c-raf-1 (3p25) and c-myc (8q24) were found to be translocated to the der(8) and der(3) chromosomes, respectively. The possible role that the relocation of c-myc might have on the development of renal carcinoma in carriers of this 3;8 translocation was further studied by analysis of the region surrounding the c-myc gene. By the use of cosmid cloning, no rearrangement 31 Kb 5'(or 19 Kb 3') of the translocated gene was found, indicating that the break-point is not immediately adjacent to c-myc. In an associated study, the DNA fragment D3S2 from chromosome 3 was found to map to 3p14.2-pter. This assignment in conjunction with published somatic cell hybrid data enabled D3S2 to be mapped more precisely to the interval 3p14.2-3p21.
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1812
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Li F, Zhang MZ, Lu LT. [Spontaneous rupture of the bladder: report of 9 cases]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 1986; 24:687-8, 701. [PMID: 3568885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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1813
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Li F, Lim CK, Peters TJ. A high-performance-liquid-chromatographic method for the assay of coproporphyrinogen oxidase activity in rat liver. Biochem J 1986; 239:481-4. [PMID: 3814086 PMCID: PMC1147306 DOI: 10.1042/bj2390481] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
An h.p.l.c. method was developed for the assay of coproporphyrinogen oxidase activity in rat liver. The protoporphyrinogen IX formed is completely oxidized to protoporphyrin IX for separation and quantification by reversed-phase chromatography with mesoporphyrin as the internal standard. The Km of coproporphrinogen oxidase is 1.01 +/- 0.23 microM. The activities are 4.07 +/- 0.40 nmol of protoporphyrin IX/h per mg of mitochondrial protein and 224 +/- 19 nmol of protoporphyrin IX/h per g of liver tissue homogenate. The method is sensitive enough for measuring enzyme activity in small amounts of human tissue from needle biopsy.
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1814
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Turc-Carel C, Dal Cin P, Limon J, Li F, Sandberg AA. Translocation X;18 in synovial sarcoma. CANCER GENETICS AND CYTOGENETICS 1986; 23:93. [PMID: 3017544 DOI: 10.1016/0165-4608(86)90153-6] [Citation(s) in RCA: 125] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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1815
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Li F, Lim CK, Peters TJ. Analysis of urine and faecal porphyrins by HPLC coupled to an advanced automated sample processor. Biomed Chromatogr 1986; 1:93-4. [PMID: 3507215 DOI: 10.1002/bmc.1130010208] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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1816
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Lim CK, Li F, Peters TJ. High-performance liquid chromatography of uroporphyrinogen and coproporphyrinogen isomers with amperometric detection. Biochem J 1986; 234:629-33. [PMID: 3718489 PMCID: PMC1146618 DOI: 10.1042/bj2340629] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A reversed-phase h.p.l.c. system, with an ODS-Hypersil column with acetonitrile or methanol in ammonium acetate buffer as mobile phase, is described for the separation of uro-and copro-porphyrinogen isomers. The porphyrinogens are detected amperometrically with sensitivity comparable with that of the fluorescent detection of porphyrins. The effects of pH, buffer concentration and organic modifiers on retention and resolution were studied. The method is suitable for both analytical and preparative separation of porphyrinogens.
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1817
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Li F, Lim CK, Peters TJ. Reversed-phase high-performance liquid chromatography of conjugated and unconjugated bilirubins in body fluids. J Chromatogr A 1986; 353:19-26. [PMID: 3700514 DOI: 10.1016/s0021-9673(01)87072-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A novel high-performance liquid chromatography (HPLC) system is described for the separation of bilirubin and its conjugates in body fluids. Biliary bilirubin mono- and diglucuronide can be analysed directly on a C18 reversed-phase column with acetonitrile-dimethyl sulphoxide-0.1 M ammonium acetate (pH 5.16) (50:50:85, v/v/v) as mobile phase. However, the simultaneous determination of conjugated and unconjugated bilirubins in plasma required conversion of the conjugates into their methyl esters by alkaline methanolysis before HPLC separation of the C18 column eluted with acetonitrile-dimethyl sulphoxide-0.50 M ammonium acetate (pH 4.6) (50:50:40, v/v/v). The method is superior to, and more flexible than, previously described reversed-phase systems by allowing precise control of retention times by adjustment of pH, buffer concentration and the relative proportion of organic modifier in the mobile phase.
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1818
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Li F. [Seroepidemiological survey on dengue virus infection in various areas of Guangdong and Guangxi Provinces]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 1985; 6:330-2. [PMID: 3914373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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1819
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Yen YC, Kong LX, Lee L, Zhang YQ, Li F, Cai BJ, Gao SY. Characteristics of Crimean-Congo hemorrhagic fever virus (Xinjiang strain) in China. Am J Trop Med Hyg 1985; 34:1179-82. [PMID: 2422968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Virus strains isolated from blood of patients during a hemorrhagic fever outbreak in 1968 in southern Xinjiang, China, from Hyalomma asiaticum and from sheep, were found to be identical or closely related to Crimean-Congo hemorrhagic fever (C-CHF) virus by complement fixation and indirect immunofluorescence tests with convalescent sera of patients and with C-CHF reference antibody. The virus was inactivated by ether and acid. Viral synthesis was not suppressed by 5-iododeoxyuridine suggesting an RNA-containing genome. The buoyant density in sucrose was 1.16-1.18 g/cm3. The particle weight was estimated at 3.26 +/- 0.46 X 10(8). The diameter of the virus particles was 85-105 nm.
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1820
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1821
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Li F. [Carcinogenic action of chlordimeform give orally to mice in a lifetime experiment]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 1985; 19:154-6. [PMID: 4053830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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1822
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Jiang Y, Zhao ZC, Li F. [The relationship between daphnetin analgesia and central neurotransmitters of monoamines]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1984; 19:647-50. [PMID: 6152596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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1823
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Wang YL, Jin XP, Jiang XZ, Lin HF, Li F. Percutaneous absorption of radioactively labelled pesticides. A summary of 20 years' research. Chin Med J (Engl) 1984; 97:443-6. [PMID: 6437765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
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1824
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Wei SL, Li F. [Application of diffuse reflectance spectra in studying the stability of solid drugs]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1983; 18:843-848. [PMID: 6679977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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1825
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Li DZ, Cao ZD, Gao XL, Li F. [Antagonistic action of ethylene-dimethyl sulfonate and its derivatives to human chorionic gonadotropin]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1983; 18:813-7. [PMID: 6093428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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