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31.
Male mice Sfis:Pzh were exposed to X-rays, cyclophosphamide or combination of both agents. Each of agent was given in low (0.25 Gy, 25 mg/kg bw CP) or high (1.00 Gy, 100 mg/kg bw CP) doses. Germ cells were exposed to agents as spermatogonia. After 35 days sperm abnormalities test was performed. Exposure to one of agents only, did not enhance statistically significant frequency of morphologically abnormal spermatozoa. Combined treatment of spermatogonia to both agents in low as well in high doses induce clear biological effects, but only combination of high doses (1.00 Gy + 100 mg/kg bw CP) induce statistically significant effect. Results obtained in this study confirmed, that ability of different agents to induce sperm-shape abnormalities is related to its ability to induce mutations in germ cells. 相似文献
32.
磺胺类药物的毛细管高效液相色谱与电色谱研究 总被引:4,自引:0,他引:4
目的 研究毛细管高效液相色谱(μ-HPLC)和毛细管电色谱(CEC)分离磺胺类药物,建立药物微分离分析方法。方法 用ODS柱为固定相,甲醇和2 mmol·L-1磷酸缓冲液(pH 3.0~7.0)为流动相,电压为0~-15 kV,流速为10 μL·min-1,紫外检测波长254 nm。结果μ-HPLC在甲醇-2 mmol·L-1磷酸缓冲液(30∶70),pH 3.0时5种磺胺类药物实现基线分离;CEC在电压为-5 kV,甲醇-2 mmol·L-1磷酸缓冲液(30∶70),pH 5.0时5种磺胺类药物实现基线分离。结论电渗流随甲醇含量、缓冲液浓度增加而下降,随pH值、电压的增加而增加;溶质的保留值(k)随甲醇含量、缓冲液浓度、电压的增加而下降,随电压增加下降明显的是TMP,随pH值变化较复杂。在相同条件下对5种磺胺类药物的分离,μ-HPLC需67 min,CEC只需25 min,后者更适合于磺胺类药物的快速分离分析。 相似文献
33.
34.
Identification of differentially expressed genes in aflatoxin B1- treated cultured primary rat hepatocytes and Fischer 344 rats 总被引:4,自引:1,他引:4
Harris AJ; Shaddock JG; Manjanatha MG; Lisenbey JA; Casciano DA 《Carcinogenesis》1998,19(8):1451-1458
Aflatoxin B1 (AFB1), a mutagen and hepatocarcinogen in rats and humans, is
a contaminant of the human food supply, particularly in parts of Africa and
Asia. AFB1-induced changes in gene expression may play a part in the
development of the toxic, immunosuppressive and carcinogenic properties of
this fungal metabolite. An understanding of the-role of AFB1 in modulating
gene regulation should provide insight regarding mechanisms of AFB1-induced
carcinogenesis. We used three PCR- based subtractive techniques to identify
AFB1-responsive genes in cultured primary rat hepatocyte RNA: differential
display PCR (DD-PCR), representational difference analysis (RDA) and
suppression subtractive hybridization (SSH). Each of the three techniques
identified AFB1- responsive genes, although no individual cDNA was isolated
by more than one technique. Nine cDNAs isolated using DD-PCR, RDA or SSH
were found to represent eight genes that are differentially expressed as a
result of AFB1 exposure. Genes whose mRNA levels were increased in cultured
primary rat hepatocytes after AFB1 treatment were corticosteroid binding
globulin (CBG), cytochrome P450 4F1 (CYP4F1), alpha-2 microglobulin,
C4b-binding protein (C4BP), serum amyloid A-2 and glutathione S-transferase
Yb2 (GST). Transferrin and a small CYP3A-like cDNA had reduced mRNA levels
after AFB1 exposure. Full-length CYP3A mRNA levels were increased. When
liver RNA from AFB1-treated male F344 rats was evaluated for transferrin,
CBG, GST, CYP3A and CYP4F1 expression, a decrease in transferrin mRNA and
an increase in CBG, GST, CYP3A and CYP4F1 mRNA levels was also seen.
Analysis of the potential function of these genes in maintaining cellular
homeostasis suggests that their differential expression could contribute to
the toxicity associated with AFB1 exposure.
相似文献
35.
Effect of genetic modification of acute inflammatory responsiveness on tumorigenesis in the mouse 总被引:1,自引:3,他引:1
36.
Sarah B. Laditka PhD ; James N. Laditka DA PhD ; Kevin J. Bennett MS PhD ; Janice C. Probst PhD 《The Journal of rural health》2005,21(2):158-166
CONTEXT: Pregnancy complications affect many women. It is likely that some complications can be avoided through routine primary and prenatal care of reasonable quality. PURPOSE: The authors examined access to health care during pregnancy for mothers insured by Medicaid. The access indicator is potentially avoidable maternity complications (PAMCs). Potentially avoidable maternity complications are often preventable through routine prenatal care, such as infection screening and treatment. The authors examined the risks of potentially avoidable maternity complications among rural and urban hospital deliveries for groups of mothers defined by race or ethnicity. METHODS: Data are from the year 2000 Nationwide Inpatient Sample (NIS). The stratified sample represents all discharges from 20.5% of community hospitals in the United States. The Nationwide Inpatient Sample identifies hospital locations, but not patients' areas of residence. Analyses, which accounted for the sample design, included calculation of potentially avoidable maternity complication rates by race or ethnicity, chi2, t tests, and multivariate logistic regression. FINDINGS: Within groups defined by race or ethnicity, unadjusted rates for potentially avoidable maternity complications did not differ significantly by hospital location. Holding other factors constant, potentially avoidable maternity complications were less common in rural hospitals than in urban hospitals (odds ratio, 0.78; CI, 0.62 to 0.99). In rural hospitals, African Americans had notably higher risk for potentially avoidable maternity complications than did non-Hispanic whites (odds ratio, 1.72; CI, 1.26 to 2.36). In urban hospitals, risk of potentially avoidable maternity complications was not significantly higher for African Americans. Hispanics and Asians had notably lower risks of potentially avoidable maternity complications in urban hospitals than did non-Hispanic whites. CONCLUSIONS: Providers and policymakers should work to reduce the risks of potentially avoidable maternity complications for African American women in rural areas who are insured by Medicaid. 相似文献
37.
38.
目的:了解女性吸毒人员社会化基本状况,并对其应对方式进行分析。方法:问卷调查、个案访谈及对在册病案进行回顾性分析及采用单因素Logistic回归分析。结果:诱发女性吸毒的因素众多,采用单因素Logistic回归分析OR值2 0以上,并有显著性意义的因素有:受教育程度、职业状况、婚姻状况、好奇、同伴影响、感情受挫、寻求刺激和减肥。结论:社会化不足是导致女性吸毒、影响其戒毒和保持戒毒后操守的重要因素,有针对性地对女性吸毒人员实施有效的社会化治疗是必要和有效的。 相似文献
39.
Tear of the distal biceps brachii tendon is an uncommon injury. Ultrasound evaluation of the distal tendon using an anterior approach is often difficult because of technical factors. We describe a new method of ultrasound evaluation of the distal biceps tendon insertion. This involves a posterior approach with the forearm pronated. With pronation of the forearm, the radial tuberosity faces posteriorly, bringing the distal biceps tendon insertion into view. A surgically proven case of distal biceps tendon tear is presented to illustrate our technique. 相似文献
40.
目的探讨参麦联合川芎嗪注射液对脓毒症小鼠肝脏的保护作用。方法采用盲肠结扎穿孔(Cecal ligation and puncture,CLP)方法诱导形成脓毒症。将雄性成年的昆明小鼠随机分为5组,分别是假手术组、模型组、参麦注射液治疗组、川芎嗪注射液治疗组和参麦联合川芎嗪注射液治疗组。CLP术前24,12,1 h各组小鼠分别腹腔注射参麦注射液和川芎嗪注射液或者等计量的生理盐水。观察CLP造模后24 h各组小鼠血清中肿瘤坏死因子α(TNF-α)、白介素6(IL-6)含量、谷丙转氨酶(ALT)、谷草转氨酶(AST)活性以及肝脏组织中丙二醛(MDA)、髓过氧化物酶(MPO)水平,并观察各组小鼠的存活率及其肝脏组织的病理变化。结果参麦、川芎嗪及参麦联合川芎嗪三组药物治疗组的脓毒症小鼠其死亡率、血清中炎症因子(TNF-α、IL-6)含量、肝脂质过氧化(MDA、MPO)水平、ALT/AST及其肝脏病理损伤程度均较模型组明显减轻,尤以参麦联合川芎嗪给药治疗组疗效最为显著。此外,联合给药治疗组血清中的炎症因子(TNF-α、IL-6)水平较单一用药组显著降低。结论参麦联合川芎嗪注射液较单一用药能够更有效地抑制炎症反应,提高脓毒症小鼠的存活率、减轻肝脏损伤。 相似文献