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41.
Comparison of urinary bladder function in sexually mature and immature male and female rats 总被引:2,自引:0,他引:2
Although studies exist using both male and female rats, there are virtually no studies that compare male and female bladder function. In this initial study, in-vivo and in-vitro urinary bladder function was investigated in two age groups of male and female rats (sexually immature and sexually mature). These studies compare in-vivo micturition behavior (water intake, urine output, frequency and volume per micturition); and in-vitro whole bladder function (bladder volume/pressure relationships, the ability of the in-vitro bladders to generate pressure and empty in response to bethanechol and field stimulation). The results can be summarized as follows: 1) The 24 hour water intake, urine output, and volume per micturition for the mature male rats was significantly greater than that of the mature females with no significant differences among the immature females, mature females, or immature males. 2) There were no significant differences in the frequency of micturition between the 4 groups. 3) Although the average plateau pressures (cystometrograms) of the immature and mature female bladders were greater than that of the immature and mature male bladders, the compliance was similar for all groups. 4) The maximum pressure response of the mature female bladder was significantly greater than pressures generated by bladders in the other three groups; there were no age or sex related differences in the bethanechol log ED50 values. 5) There were no age or sex-related differences in the bethanechol log ED50 values or maximal expulsion responses. 6) Field stimulated bladders from mature animals generated significantly greater intravesical pressures than bladders from immature animals, but, there were no significant differences in maximal pressures attained between mature male and female bladders nor between immature male and female bladders. In conclusion, micturition behavior, and the maximal pressure response to bethanechol changed dramatically with sexual maturity. These results are consistent with the idea that estrogen and other hormones may have a marked influence on bladder function and micturition behavior. 相似文献
42.
组织扩张术皮肤胶原的代谢改变 总被引:4,自引:0,他引:4
目的:研究常规扩张(ITE)和持续快速扩张(CTE)对皮肤胶原代谢的影响。方法用白色小家猪制作组织扩张术动物模型,用Gordeladze法测定血清和扩张组织的羟脯氨酸(HP)含量,藻酸盐印模材膜片法测量标记区面积;光镜测量真皮厚度。结果:ITE组血清HP含量升高,0.8倍,CTE组升高1.2倍,ITE和CTE组皮肤含量与正常皮肤相同,组织中HP总量均明显升高,持续扩张皮瓣组(CTEF)术后4wk皮 相似文献
43.
The cellular and regional distribution of glutathione (GSH) and GSH-related enzyme systems involved in cellular defense against reactive oxygen species and electrophilic xenobiotics in the nervous system has been extensively studied. However, little is known about the subcellular distribution of GSH systems in brain tissue and cultured neural cells. The present study investigates the distribution of mitochondrial and cytosolic GSH and GSH-related enzymes in cultured cerebellar astrocytes and granule cells, and compares them with levels in the adult rat cerebellum. Cytosolic GSH levels and cytosolic activities of glutathione reductase (GR), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) in astrocytes were 57, 153, 245, and 92% higher than those found in granule cells, respectively. In contrast, granule cells contained significantly higher mitochondrial GSH levels than astrocytes. Granule cells also demonstrated comparable mitochondria/cytosolic concentrations of GSH and GR, GPX and GST activities to those observed in the cerebellar tissue, whereas ratios in astrocytes were markedly lower. Although in vitro treatments with 100 μM ethacrynic acid depleted both cytosolic and mitochondrial GSH in cultured astrocytes and granule cells in a time-dependent fashion, cellular GSH in granule cells was more resistant to the GSH-depleting agent than astrocytes. These results suggest that although GSH and GSH-related enzymes are abundant in cytosolic compartments of astrocytes, mitochondrial pools are relatively small. Since brain mitochondria are sites of significant hydrogen peroxide generation, the mitochondrial localization of GSH and its associated enzymes in neural cells provide important defenses against toxic oxygen species in the nervous system. Differences in subcellular distribution of GSH systems in individual neural cell types may provide a basis for selective cellular and/or subcellular expression of neurotoxicity. 相似文献
44.
胃癌D17S261和D17S799位点二核苷酸重复序列不稳定性的意义 总被引:2,自引:2,他引:0
目的研究二核苷酸重复序列不稳定性〔DRSI〕在胃癌发生中的作用及其临床意义.方法采用PCR方法检测了D17S261和D17S799位点二核苷酸重复序列不稳定性.结果胃癌总DRSI发生率为34%(17/50),其中高中分化腺癌DRSI阳性率(667%,10/15)显著高于低分化癌(194%,6/31,P<001);肠型胃癌DRSI阳性率(556%,10/18)显著高于胃型胃癌(20%,6/30,P<005),DRSI与胃癌部位、大小、浸润、分期、淋巴结转移无显著相关.结论DRSI在胃癌的发生中可能起重要作用. 相似文献
45.
复方栀子冲剂栀子甙薄层扫描测定 总被引:11,自引:0,他引:11
应用薄层扫描法测定了复方栀子冲剂中栀子甙的含量,对实验条件,以正交试验法进行优选,确定了最佳方案,排除了干扰,得到了满意的效果。 相似文献
46.
脊髓手术中体感诱发电位监测的临床研究 总被引:3,自引:0,他引:3
报告30例脊髓手术中体感诱发电位(SEP)连续监测的临床研究结果。SEP记录包括脊髓SEP(SSEP)和皮层SEP(SCEP)。麻醉药物对SEP有一定程度影响,SCEP相对较大。认为,至少术中SEP潜伏期延长不超过8%和波幅降低不超过50%,不会引起术后并发症,超过该范围由于病例较少,尚不能肯定与预后的关系,需进一步探讨。 相似文献
47.
本文在分析黑龙江省妇幼保健机构设置现状的基础上,论述了在社会主义市场经济新形势下,妇幼保健机构发展的指导思想、模式与对策。 相似文献
48.
目的:探讨Mirizzi综合征的发病机理、临床表现、影像学诊断及术前诊断的重要价值.方法:查阅了大量的相关资料文献,进行对比、分析、总结归纳.结果:Mirizzi综合征是胆道系统感染的一种特殊类型,临床少见,极易造成漏诊和误诊,在术中造成不必要的胆道损伤和胆总管探查,影像学检查在诊断此综合征方面有较多的独特优势.结论:Mirizzi综合征术前可以通过影像学检查尤其是超声检查明确诊断. 相似文献
49.
卓见 《中国医学文摘:外科学分册英文版》2007,16(2):141-141
Objective To compare the safety and short-term efficacy of thulium laser resection of the prostate-Tangerine technique (TmLRP-TT) and treatment of benign prostatic hyperplasia (BPH) patients.Methods A total of 124 patients who were diagnosed with BPH were randomly divided into 2 groups: 相似文献
50.
固生蛋白tenascin对肝细胞癌血管生成及浸润转移的影响 总被引:1,自引:0,他引:1
目的 探讨固生蛋白(tenascin ,TN)在肝细胞癌(hepatocellularcarcinoma ,HCC)中的表达和与HCC血管生成及浸润转移的关系。方法 应用免疫组织化学法检测4 2例HCC、10例肝硬化和7例正常肝组织内TN的表达情况,观察与HCC病理学特点及微血管密度(microvesseldensity ,MVD)之间的关系。结果 ①TN在HCC中的阳性表达率和强度显著高于肝硬化和正常肝脏组织( χ2 =4 15 ,P <0 0 5 ;t=2 4 73,P <0 0 5 ) ;②TN在有包膜侵犯组、病理分级Ⅲ~Ⅳ组及有转移HCC中的阳性表达率及强度明显高于无包膜侵犯组( χ2 =5 4 7,P <0 0 5 ;t=2 138,P <0 0 5 )、病理分级Ⅰ~Ⅱ级组( χ2 =6 87,P <0 0 1;t=2 4 79,P <0 0 5 )以及无转移组( χ2 =10 6 ,P <0 0 1;t=2 6 93,P <0 0 1) ;③肝癌>5cm、有包膜侵犯、有转移、病理分级Ⅲ~Ⅳ级组的MVD值明显高于肝癌≤5cm(t=2 0 36 ,P <0 0 5 )、无包膜侵犯(t =2 32 8,P <0 0 5 )、无转移(t =2 4 94 ,P <0 0 5 )及病理分级Ⅰ~Ⅱ级组(t =2 2 71,P <0 0 5 )。④TN阳性表达HCC中的MVD值明显高于TN阴性表达HCC中的MVD值(t =2 4 87,P <0 0 5 )。结论 TN在HCC组织中的表达上调与其血管生成和浸润转移有关 相似文献