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首次测定确立高催乳血症必需避免过度的静脉穿刺压力,理想的情况是醒后或饭后致少1h来测试.  相似文献   
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Mutagenesis by the human bladder carcinogen 4-aminobiphenyl (ABP) was studied in single-stranded DNA from a bacteriophage M13 cloning vector. In comparison to ABP lesions in double-stranded DNA, lesions in single- stranded DNA were approximately 70-fold more mutagenic and 50-fold more genotoxic. Sequencing analysis of ABP-induced mutations in the lacZ gene revealed exclusively base-pair substitutions, with over 80% of the mutations occurring at G sites; the G at position 6310 accounted for 25% of the observed mutations. Among the sequence changes at G sites, G- ->T transversions predominated, followed by G-->C transversions and G-- >A transitions. In order to further elucidate the mutagenic mechanism of ABP, an oligonucleotide containing the major DNA adduct, N- (deoxyguanosin-8-yl)-4-aminobiphenyl (dG(8-ABP)), was situated within the PstI site of a single-stranded M13 genome. After in vivo replication of the adduct containing ABP-modified and control (unadducted) genomes, the mutational frequency and mutational specificity of the dG(8-ABP) lesion were determined. The targeted mutational efficiency was approximately 0.01%, and the primary mutation observed was the G-->C transversion. Thus dG(8-ABP), albeit weakly mutagenic at the PstI site, can contribute to the mutational spectrum of ABP lesions.   相似文献   
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Chou  HC; Ozawa  S; Fu  PP; Lang  NP; Kadlubar  FF 《Carcinogenesis》1998,19(6):1071-1076
Methyl-hydroxylated metabolites of the potent carcinogen, 7,12- dimethylbenz[a]anthracene (DMBA), namely, 7-hydroxymethyl-12- methylbenz[a]anthracene (7-OH-DMBA), 7-methyl-12- hydroxymethylbenz[a]anthracene (12-OH-DMBA) and 7,12- dihydroxymethylbenz[a]anthracene (7,12-diOH-DMBA), were examined as substrates for sulfotransferase bioactivation in different human tissue cytosols. Hepatic cytosols, which were able to catalyze the 3'- phosphoadenosine 5'-phosphosulfate (PAPS)-dependent DNA binding of 7-OH- DMBA, 12-OH-DMBA and 7,12-diOH-DMBA, were highly sensitive to inhibition by dehydroepiandrosterone (DHEA), a specific substrate for human DHEA-steroid sulfotransferase (IC50 = 5 microM). By comparison, 2,6-dichloro-4-nitrophenol, a potent inhibitor of the thermostable (TS)- phenol and estrogen sulfotransferases, did not have an appreciable inhibitory effect. Neither p-nitrophenol, a high affinity substrate for human TS-phenol and estrogen sulfotransferases, nor dopamine, a specific substrate for the thermolabile (TL)-phenol sulfotransferase, significantly inhibited the DNA binding of 12-OH-DMBA catalyzed by hepatic cytosols. Inter-subject variation (n = 12) of the PAPS- dependent DNA binding of 12-OH- and 7,12-diOH-DMBAs also correlated well with DHEA-sulfotransferase activity (r = 0.90; P < 0.00001 and r = 0.92; P < 0.00001, respectively). This sulfation-dependent metabolic activation was not detected in cytosols from human colon, pancreas, larynx or mammary gland. Both TS- and TL-phenol sulfotransferases were active in human liver and colon but only liver contained DHEA- sulfotransferase activity. These results indicate that the sulfotransferase-mediated activation of the methyl-hydroxylated DMBAs is predominantly catalyzed by DHEA-steroid sulfotransferase in human liver and that TS- and TL-phenol sulfotransferases and estrogen sulfotransferase are not involved in the catalysis.   相似文献   
56.
Lymphoid cells from patients with rheumatoid arthritis were compared with those from healthy blood donors and from nonrheumatoid arthritis patients for the ability to manifest in vitro cytotoxicity against target cells in the presence of phytohemagglutinin (PHA) or anti-target cell antibodies. The PHA-induced cytotoxicity in the rheumatoid patient group was significantly lower than that of the blood donors (P < 0.01) and of the nonrheumatoid patients (P < 0.05). The rheumatoid arthritis patients appeared to fall into two groups, one with normal and one with distinctly subnormal PHA-induced cytotoxicity. No obvious differences were observed between these two groups with regard to duration or activity of the disease, treatment, autoantibodies, or the proportion in peripheral blood of T lymphocytes (E–RFC) or Fc-receptor-bearing lymphocytes (EA-RFC). There were no significant differences between the groups with regard to antibody-dependent cytotoxicity.  相似文献   
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AIDS case reporting has been an essential tool for monitoring HIV infection in western Europe. Recent trends in AIDS have been affected by improved antiretroviral treatments that delay HIV disease progression, however, and no longer serve as indicators of  相似文献   
59.
We describe recurrent bilateral homocystinuria-related lens dislocation into the anterior chamber in a patient who had postoperative anterior staphyloma and secondary intractable aphakic glaucoma in only one eye. We discuss the possible causes of and treatment modalities for this complication.  相似文献   
60.
INTRODUCTION: The type of skin incision affects the course of surgery during radical nephrectomy. We investigated the efficacy of a new type of incision for the surgical approach to large renal masses. PATIENTS AND METHODS: Fourty patients (23 males and 17 females, mean age 63 years) who underwent radical nephrectomy in our department between 2002 and 2004 were evaluated. The outcomes in the groups with chevron incision and abdominal wall flap incision (AFI) were compared in terms of greatest tumor diameter, operation duration, perioperative blood loss, postoperative complications, and duration of hospitalization. Statistical analysis was made by independent-samples t test. RESULTS: Chevron incision was used in the first 15 patients, while subsequent 25 patients were operated via AFI. The operation duration was slightly longer in the AFI group (3.78 vs. 3 h); however, the mean largest tumor diameter was significantly greater in patients operated via AFI (11.3 vs. 7.4 cm, p < 0.05). The mean blood losses were 1,100 and 590 ml in the chevron incision and AFI groups, respectively (p < 0.05). There was no significant difference in terms of duration of hospitalization and postoperative morbidity. CONCLUSION: In our experience, AFI provides the best exposure and improved control of renal vessels and vena cava during radical nephrectomy and enables a safe dissection even in very large tumors with minimal blood loss.  相似文献   
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