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1.
The evaluation of the data obtained during the behaviour tests always leads to the problem of multiple correlation, very often with non-linear dependencies on the target. All mathematical and statistical procedures that have been used so far are based on the assumption of an equation for the desired correlation for which parameters and related statistical equivalents are determined eventually. The MODAK system applied here (MODAK = algorithms of modelling for the calculation of multi-dimensional non-linear mathematical models) breaks down a complex correlation into individual dependencies in a mathematical and statistical way and selects suitable equations for each of them independently and determines the corresponding parameters. The numerical example evaluates data of behaviour tests on rats. First results obtained on the correlations of various behaviour tests indicate both the possibility of selecting suitable tests independent of each other and a better interpretation of the observed patterns of behaviour taking into account the interrelations between the tests. In addition, MODAK is a method which can be applied as a matter of course in a general way to all cases which call for the reduction and analysis of data occurring in process and system analysis and in the evaluation of test results requiring statistical modelling. So far, MODAK applications range from engineering sciences to medicine.  相似文献   
2.
Summary Light-microscopic immunohistochemistry was used to localize insulin- and somatostatin-immunoreactive cells within developing endocrine pancreatic tissue of metamorphosing lampreys, Petromyzon marinus. The extrahepatic common bile duct and a portion of the intrahepatic bile duct develop into the caudal portion of the endocrine pancreas. The cranial pancreas is composed of follicles originating in the intestinal and diverticular epithelia, thus following the method of formation of pancreatic follicles from gut epithelium in larvae. In both the cranial and caudal portions, and in an intermediate cord of isolated follicles which connect these two major masses, insulin-immunoreactive cells appear first and are followed by cells showing somatostatin-immunoreactivity. In all stages of metamorphosis individual endocrine cells demonstrate immunoreactivity to a single hormone. Biliary atresia in lamprey may have some adaptive significance in providing cells that produce a caudal endocrine pancreas.Supported by NSERC of Canada grant No. A5945 and MRC of Canada grant No. MA8629 to JHY  相似文献   
3.
The increased expiration of ethane and pentane by mice treated with hepatotoxic doses of acetaminophen suggests the possibility of oxidant mechanisms associated with the necrosis. However, studies in rats are not consistent with oxidant stress mechanisms causing the damage, because acetaminophen given to rats does not increase GSSG efflux, a sensitive index of intrahepatic oxidant stress. To compare the extent of oxidant stress generated by acetaminophen in mice versus rats, hepatic content and biliary efflux of GSSG and GSH in mice have been examined. Bile was collected from anesthetized male ICR mice before and after intraperitoneal administration of acetaminophen (325 mg/kg, 2.15 mmol/kg), t-butyl hydroperoxide (TBHP) (1.5 mmol/kg), diethyl maleate (400 mg/kg, 2.33 mmol/kg, in corn oil) or saline (control) and GSH and GSSG were measured by the enzymatic recycling method of Tietze. An increase in biliary GSSG efflux was produced by t-butyl hydroperoxide, but not by the other agents. Biliary GSH/GSSG ratios decreased in acetaminophen-treated animals, presumably reflecting the marked depletion of hepatic GSH, since a similar decrease was observed with non-hepatotoxic doses of diethyl maleate. The failure of acetaminophen to increase the hepatic content or biliary efflux of GSSG in ICR mice is not consistent with the view that oxidant stress mechanisms cause the damage, despite the increases in alkanes expired after acetaminophen administration in this specific animal model.  相似文献   
4.
Abstract Salmonella serotype typhimurium transpositional mutants altered in resistance to biliary salts and detergents were isolated previously. We have characterized further the LX1054 mutant strain, the most sensitive of them. The chromosomal DNA segment flanking transposon insertion was cloned and sequenced. The highest level of identity was found for the acrB (formerly acrE ) gene of Escherichia coli , a gene encoding a drug efflux pump of the Acr family. LX1054 exhibited a reduced capacity to colonize the intestinal tract. After passages in mice, the mutant strain lost the sensitive phenotype. In vitro, a resumption of growth appeared after 17 h of culture in medium with cholate or other tested biological or chemical detergents. Then, the acquired resistant phenotype seemed stable. The data suggested a role of S. typhimurium acrB -like gene in resistance to biliary salts and detergents and in mice intestinal colonization. However, the local and transient sensitivity observed in vivo, and the in vitro adaptations suggest that several detergent-resistance mechanisms operate in S. typhimurium .  相似文献   
5.
Summary The bile canalicular network of the monkey was studied by fracturing fixed liver tissue and examination by scanning electron microscopy. Bile canaliculi do not differ remarkably from those described in other species. Their course and luminal diameter vary, depending on their position in the liver lobule. In one specimen the continuity of a canaliculus with a terminal bile ductule (canal of Hering) is presented. Several constrictions occur in this part of the ductular lumen. The interlobular bile duct wall shows two kinds of niches. A single cilium arises from a primary niche. The walls of secondary niches contain numerous primary niches. Simple columnar epithelium lines the common bile duct, the main pancreatic duct and the gallbladder. A common feature is the presence of microplicae on their lateral cell surfaces.
Zusammenfassung Das Netzwerk der Gallekanälchen beim Affen wird durch Brechen von fixiertem Lebergewebe sichtbar. Strukturen der Portalfelder und der extrahepatischen Gänge werden durch Schneiden von Gewebe dargestellt. DieGallekanälchenunterscheidensichnichtwesentlich von den bei anderen Spezies beschriebenen. Ihr unterschiedlicher Verlauf und Lumendurchmesser hängen von ihrer intralobulären Lage ab. Die Kontinuität eines Gallekanälchens mit einem Ductulus (Heringscher Kanal) wird in einem Fall dargestellt. Im ductulären Lumen kommen mehrere Konstriktionen vor. Die Wand der interlobulären Gallengänge weist zwei Arten von Nischen auf. Eine Einzelzilie kommt aus den primären Nischen. Sekundäre Nischen bestehen aus mehreren primären Nischen. Einschichtiges hochprismatisches Epithel kleidet den Ductus choledochus, den Ductus pancreaticus und die Gallenblase aus. Ein gemeinsames Merkmal ihrer lateralen Zelloberflächen sind Mikroplicae.
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6.
The elimination, tissue distribution, and metabolism of [1-14C]perfluorooctanoic acid (PFOA) was examined in male and female rats for 28 days after a single ip dose (9.4 μmol/kg, 4 mg/kg). A sex difference in urinary elimination of PFOA-derived 14C was observed. Female rats eliminated PFOA-derived radioactivity rapidly in the urine with 91% of the dose being excreted in the first 24 hr. In the same period, male rats eliminated only 6% of the administered 14C in the urine. The sex-related difference in urinary elimination resulted in the observed difference in the whole-body elimination half-life (t1/2) of PFOA in males (t1/2 = 15 days) and females (t1/2 < 1 day). Analysis of PFOA-derived 14C in tissues showed that the liver and plasma of male rats and the liver, plasma, and kidney of female rats were the primary tissues of distribution. The relatively high concentration of PFOA in the male liver was further examined using an in situ nonrecirculating liver perfusion technique. It was shown that 11% of the PFOA infused was extracted by the liver in a single pass. The ability of the liver to eliminate PFOA into bile was examined in rats whose renal pedicles were ligated to alleviate sex differences in the urinary excretion of PFOA. In a 6-hr period following IP administration of PFOA, there was no apparent difference in biliary excretion, where both males and females eliminated less than 1% of the PFOA dose via this route. We hypothesized that the sex difference in the persistence of PFOA was due to a more rapid formation of a PFOA-containing lipid (i.e., a PFOA-containing mono-, di-, or triacylglycerol, cholesteryl ester, methyl ester, or phospholipid) in the male rat. Also, the increased urinary elimination of PFOA in females may have been due to increased metabolism to a PFOA-glucuronide or sulfate ester. However, no evidence that PFOA is conjugated to form a persistent hybrid lipid was obtained, nor were polar metabolites of PFOA in urine or bile detected. In addition, daily urinary excretion of fluoride in male and female rats before or after PFOA treatment were similar, suggesting that the parent compound is not defluorinated. Thus, the more rapid elimination of PFOA from female rats is not due to formation of a PFOA metabolite.  相似文献   
7.
8.
目的探讨输尿管软镜协同输尿管硬镜治疗复杂上尿路结石的临床效果。方法选择我院收治的复杂上尿路结石患者96例,按入院顺序分为对照组和观察组,每组48例。对照组采取输尿管硬镜钬激光碎石术治疗,观察组采取输尿管软镜协同输尿管硬镜钬激光碎石术治疗。比较两组患者1次性碎石成功率、结石彻底清除率、炎症反应情况以及生活质量、住院时间、术后并发症发生率、疾病复发率。结果观察组患者的1次性碎石成功率、结石彻底清除率均高于对照组,两组比较差异有统计学意义(均P<0.05)。术后3 d,观察组的肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)、C-反应蛋白(CRP)水平均较对照组降低,差异有统计学意义(均P<0.05)。术后1周,两组患者的生活质量比较,观察组的生活质量量表(SF-36)评分明显高于对照组,住院时间短于对照组,两组比较差异有统计学意义(均P<0.05)。两组患者的并发症发生率、疾病复发率比较,观察组均明显低于对照组,差异有统计学意义(均P<0.05)。结论输尿管软镜联合输尿管硬镜治疗复杂上尿路结石的效果满意,且创伤小,结石清除率高,不良反应低,具有一定临床应用价值。  相似文献   
9.
摘要 目的:分析熊去氧胆酸联合非诺贝特对原发性胆汁性胆管炎无熊去氧胆酸生化反应的临床疗效及安全性。方法:151例原发性胆汁性胆管炎无熊去氧胆酸患者按随机数表法分为73例对照组和78例研究组。对照组在常规治疗基础上给予安慰剂联合熊去氧胆酸治疗,研究组在常规基础上给予非诺贝特联合熊去氧胆酸治疗,两组均持续治疗12个月。比较两组临床疗效,肝功能,血脂指标,肝纤维化指标,免疫球蛋白G(IgG)、免疫球蛋白M(IgM),瘙痒及乏力评分,不良反应发生情况。结果:治疗后,研究组总有效率高于对照组,比较差异有统计学意义(P<0.05)。治疗后,两组肝功能指标均降低,研究组低于对照组,比较有统计学意义(P<0.05)。治疗后,两组总胆固醇(TC)、甘油三酯(TG)均降低,研究组低于对照组,比较有统计学意义(P<0.05),两组治疗前后低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)比较无统计学意义(P>0.05)。治疗后,两组肝纤维化指标均降低,研究组低于对照组,比较有统计学意义(P<0.05)。治疗后,两组IgG、IgM均降低,研究组低于对照组,比较有统计学意义(P<0.05)。治疗后,两组瘙痒、乏力评分均降低,研究组低于对照组,比较有统计学意义(P<0.05)。两组不良反应发生率比较差异无统计学意义(P>0.05)。结论:熊去氧胆酸联合非诺贝特对原发性胆汁性胆管炎无熊去氧胆酸生化反应的疗效较好,能够改善肝功能,且未明显增加药物不良反应。  相似文献   
10.
目的分析泌尿系统结石合并感染患者尿路病原菌分布及其危险因素,为后续研究提供参考。方法收集2016年1月至2019年1月我院诊治的430例泌尿系统结石患者为研究对象,根据患者是否发生感染分为感染组(n=34)和非感染组(n=396)。分析两组患者的临床特征和感染组患者病原菌分布情况,同时对影响患者感染的高危因素进行Logistic回归分析。结果感染组患者共计检出84株病原菌,其中革兰阳性球菌20株(23.81%),革兰阴性杆菌60株(71.43%),其他4株(4.76%)。两组患者白细胞水平、尿路梗阻情况、血肌酐水平、尿pH7.0比例、血尿素氮水平、合并肾积水情况、结石位置、结石直径、抗菌药物使用种类差异均有统计学意义(均P0.05)。合并肾积水、尿路梗阻、白细胞计数(≤10×10~9个/L)、尿pH(7.0)、血尿素氮(≥7.15 mmol/L)、结石位置(上尿路)、抗菌药物使用种类(≥3种)均为泌尿系统结石合并尿路感染的高危因素,而血肌酐水平,结石直径与泌尿系统结石合并尿路感染无明显相关性。结论泌尿系统结石患者易并发尿路感染,其病原菌以革兰阴性杆菌为主。导致尿路感染的因素较多,临床上应提前制定预防措施,降低结石患者尿路感染发生率。  相似文献   
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