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991.
Lee YJ Nam SW Seo DW Ahn SH Ko YK Sung DS Han JW Hong SY Lee HW 《Archives of pharmacal research》1997,20(3):239-246
In the present study, liver regeneration rate (%) was increased up to 70% 3 days after partial hepatectomy (PH). Nitric oxide
synthase (NOS) activity in liver tissue as well as serum nitrite/nitrate content had no timed response, revealing no significant
difference between shamoperated and partially hepatectomized rat liver. Contents of free methylarginines in liver tissue were
increased biphasically in a time-dependent manner after PH. However, those in serum did not exhibit the same patterns as in
liver. Taken together, the results suggest that NG-monomethyl-L-arginine (MMA) and NG, NG-dimethylarginine (DMA) play a role in inhibiting nitric oxide (NO) synthesis in regenerating rat liver because the increase
of their contents was synchronized with NOS expression. 相似文献
992.
The experimental hepatic cirrhosis was induced either by bile duct ligation (BDL) or by pretreatment with dimethylnitrosamine
(DMNA). The pharmacokinetics of theophylline were studied after a single intravenous or a single oral administration. Using
the ultrafiltration method, protein-drug binding experiments were also carried out. The bilirubin level was several-fold increased
by BDL, but not by DMNA treatment. The albumin content was decreased in both cirrhotic groups. The total clearance (Clt, ml/kg/hr)
of theophylline in both hepatic cirrhosis groups significantly decreased and the terminal half-life (t1/2) in the cirrhotic rats was increased about two-fold after intravenous and oral administration. The volume of distribution
at steady state (Vdss, ml/kg) was increased slightly in the cirrhotic groups. Protein binding in BDL (8.67±4.85%) decreased
about four-folds, but in DMNA (73.00±9.85%) similar result, was observed as compared with the control. Increased free fraction
of theophylline did not increase the volume of distribution in BDL. Therefore decreased total body clearance of theophylline
was mainly due to decreased intrinsic clearance of theophylline in the liver. The absolute bioavailability of theophylline
in these experiments was between 63.8 and 72.8%(66.1% in BDL, 63.8% in Sham operated and Control, 72.8% in DMNA). These results
suggest that in the experimental hepatic cirrhosis model, administration route does not affect the disposition of theophylline. 相似文献
993.
Baek NI Kim JM Park JH Ryu JH Kim DS Lee YH Park JD Kim SI 《Archives of pharmacal research》1997,20(3):280-282
A genuine dammarane-glycoside, named as ginsenoside Rs3, was isolated from the MeOH extracts of Korean red ginseng (Panax ginseng C.A. Meyer) through repeated silica gel column chromatographies and its chemical structure was determined as (20S)-protopanaxadiol 3-O-[6″-O-acetyl-β-D-glucopyranosyl (1→2)-β-D-glucopyranoside on the basis of several spectral and physical evidences including HMBC
and FAB-MS. 相似文献
994.
Xin-Da Zhou Zhao-You Tang Ye-Qin Yu Bing-Hui Yang Ji-Zhen Lu Zhi-Ying Lin Zeng-Chen Ma Bo-Heng Zhang 《Journal of cancer research and clinical oncology》1994,120(6):369-373
The long-term prognosis of surgery for hepatocellular carcinoma (HCC) is not yet satisfactory, the main reason being the high recurrence rate. The authors report the results of a long-term follow-up of 308 patients with HCC who became -fetoprotein-(AFP)-negative after resection between 1975 and 1991. By March 1992, there was recurrence in 134 patients (43.5%). The 1-, 3-, 5- and 10-year recurrence rates were 9.2%, 38.8%, 54.9% and 85.0%, respectively. The 5-year survival rate was 49.7% for patients who had undergone a second hepatic resection (n=48). Analysis of factors influencing postoperative recurrence indicated that patients subjected to mass survey, with a lower -glutamyltransferase level, at an early stage of TNM classification, with a tumour of less than 5 cm, without tumour embolus, and with postoperative immunotherapy had a lower incidence of recurrence. It is concluded that the earlier the disease is diagnosed, the less the recurrence rate; adjuvant immunotherapy may reduce postoperative recurrence, and the early detection and resection of a recurrent tumour are important to prolonging survival further after curative resection of HCC.Abbreviations HCC
hepatocellular carcinoma
- AFP
-fetoprotein
- HBsAg
hepatitis B surface antigen
Presented in part at the 4th Wilson T. S. Wang International Surgical Symposium, 11–13 December 1992, Hong Kong. 相似文献
995.
Dong WW Brau CA Waters JW Tompkins PA Carroll FC Price RR Pickens DR Roos CF 《Journal of X-ray science and technology》1994,4(4):346-352
The Vanderbilt University medical FEL (free electron laser) Compton x-ray program is close to being operational. The FEL modifications necessary for this new capability are near completion. The transport and detection systems for electron and IR beams have been designed, delivered, and tested. We initially expect to produce 108 x-ray photons per second in the 15- to 20-keV region. 相似文献
996.
Cervantes M Zhou H Sahin A Dhingra K Valero V Ordonez N Elnaggar A Hess K Glassman A Sen S 《International journal of oncology》1995,6(5):955-962
Correlation of p53 gene/protein alterations with incidence of oncogene amplification, a potential marker of prognosis, was evaluated in 26 fresh breast cancer samples. p53 gene was analyzed by SSCP and DNA sequencing while p53 protein status was investigated by immunohistochemistry (IH). Amplification of c-erbB2/neu, c-myc, N-ras, int-2, hst, PRAD-1 and EGFR genes was studied by slot blot and in situ hybridizations. p53 alterations were found in 31% cases by SSCP and 42% by IH; gene amplification was detected in 27% cases. p53 gene alterations correlated significantly with gene amplification (p=0.006) and also with higher S-phase index (p=0.026), aneuploidy (p=0.026) and negative progesterone receptor status (p=0.043). 相似文献
997.
A combined polymerase chain reaction (PCR) with the enzyme HaeIII restriction analysis and DNA sequencing have been employed to study the mutations at codon 249 of p53 gene in two human hepatocellular carcinoma (HCC) cell lines and 28 surgical specimens of HCC. 14 of the 28 HCC samples (50%) had p53 point mutations at codon 249. All of point mutations at codon 249 in 10 cases sequenced are AGG to AGT transversion. p53 gene mutated more frequently in invasive HCCs than that in non-invasive HCCs. This suggested that the codon 249 was a mutational hotspot of p53 gene in human HCCs in China, and p53 mutations may be related to tumor invasiveness of human HCC. 相似文献
998.
目的 探讨上海市≥50岁人群维生素D水平与握力的关系。方法 数据来源于WHO全球老龄化与成人健康研究我国上海市2018-2019年数据,采用logistic回归模型分析维生素D水平与握力的关系,进一步按照性别、年龄及乳制品摄入情况进行分层;采用限制性立方样条曲线绘制维生素D水平与低握力的剂量-反应曲线。结果 共4 391人纳入研究,其中男性2 054人(46.8%);年龄(67.02±8.81)岁;低握力1 421人(32.4%);维生素D不足及缺乏分别为1 533人(34.9%)和401人(9.1%)。在调整相关混杂因素后,logistic回归分析结果显示,维生素D缺乏的人群发生低握力的风险更高(OR=1.41,95%CI:1.09~1.83);在男性中,调整相关混杂因素后,维生素D缺乏与低握力发生风险呈显著正相关(OR=1.67,95%CI:1.12~2.50),而女性中两者之间无关联(OR=1.30,95%CI:0.97~1.74);在60~69岁及≥80岁年龄组中,调整相关混杂因素后,维生素D缺乏与低握力发生风险呈显著正相关(OR=1.57,95%CI:1.05~2.35;OR=2.40,95%CI:1.08~5.31),在乳制品摄入<250 ml/d的人群中,调整相关混杂因素后,二者之间呈显著正相关(OR=1.57,95%CI:1.17~2.09),而在乳制品摄入≥250 ml/d的人群中无明显关联。限制性立方条样图显示,低握力的发生风险可能随维生素D含量的上升而降低,但差异无统计学意义(P>0.05)。结论 维生素D水平与握力存在一定的关系,维生素D缺乏人群出现低握力的风险更高。 相似文献
999.
医学院校教师血压水平及高血压病患病率的调查 总被引:1,自引:1,他引:0
为探讨医学高教职业对教师血压的影响,我们对我院579名在职教师的血压及其高血压患病率进行了统计分析,并同对照组进行了比较。结果表明,高教教师无论在总体上,还是与相同工龄段的其他人群相比较,其血压水平及高血压患病率均显著增高(P<0.05,P<0.01),而且随高教教龄的延长,血压及高血压患病率均有明显增高的趋势(P<0.05,P<0.01);中青年高级职称者血压水平较非高级职称者明显增高(P<0.01)。从而提示高教职业长期紧张、高负荷、大工作量的特点是高教教师高血压病患病率增高的重要因素,高教教师尤其高教龄教师是高血压病的高危人群。 相似文献
1000.
用PCR法对100例早孕妇女的子宫颈标本和绒毛组织进行沙眼衣原体(CT)检测,结果发现:孕妇宫颈感染率为11%(11/100),绒毛感染率为7%(7/100),在11例宫颈CT阳性的孕妇中,发现有5例绒毛CT为阳性(45.5%)。同时显示无业、个体经商者、多次妊娠(>3次)、宫颈糜烂分别是孕期感染CT的高危人群和重要因素。结论:在孕期保健中,应开展CT筛查,尤其对具有高危因素的孕妇进行检查,以利于早期发现衣原体感染,及时治疗,从而提高人口素质。 相似文献