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71.
Testicular seminoma with elevated serum human chorionic gonadotropin level (hCG-positive seminoma) is regarded as more malignant than marker-negative seminoma, although Its prognosis is still unclear. To clarify the malignant potential of seminoma with hCG production, the serum levels of the beta subunit of hCG (β-hCG) and lactic acid dehydrogenase (LDH) were examined in 35 and 40 patients, respectively, and the Immunohistochemical expression of β-hCG examined in 45 tumors. The elevation of the LDH serum level correlated to the Invasive status, metestatic status and poor outcome, while that of the serum β-hCG level correlated only to the metastatic status. Immunohistochemical expression of β-hCG was observed in syncytiotrophoblastic giant cells in 11 tumors and a few mononuclear seminoma cells In 36 tumors. Expression was not associated with the malignancy potential, except where the expression In mononuclear cells Inversely correlated to the invasive status. These results suggest that most seminomas produce a slight amount of hCG; that an elevated hCG serum level Indicates the pressnce of metastatic tumors and mainly reflects an increase in tumor volume but not in cellular malignancy potential; and that the LDH serum level, rather than hCG, is more useful as a prognostic indicator for patients with seminoma.  相似文献   
72.
为证明癫痫发作早期一氧化氮(NO)抗发作效应,用NO合酶(NOS)抑制剂L-硝基精氨酸甲酯(L-NAME)对大鼠红藻氨酸(KA)诱导性发作进行干预,同时用分光光度法检测海马结构中NOS活性的早期变化。发现KA发作10min、30min组海马结构中NOS活性明显升高,而KA注射前30min给予L-NAME可显著抑制NOS活性的升高,这种抑制效应与大鼠KA发作中湿狗样摇动(WDS)的提早出现和发生次数增多显著相关。结果提示在KA诱导大鼠发作早期内源性NO具有明显的抗发作效用。  相似文献   
73.
The database of the Hungarian randomised controlled trial of periconceptional multivitamin supplementation for the prevention of neural-tube defects was used to evaluate the length of the pre- and postovulatory phases of the menstrual cycle before and during multivitamin supplementation. The female cycle was more regular (i.e., the variance was lower) during the multivitamin supplementation.  相似文献   
74.
侧脑室注射甘氨酸使健康家兔和烧伤家兔血浆皮质酮浓度降低;注射L—谷氨酸和L—天冬氨酸使健康家兔血浆皮质酮浓度升高,但不能使烧伤后升高的血浆皮质酮浓度发生改变。提示这三种氨基酸作为神经递质参与下丘脑—垂体—肾上腺皮质轴的调控。烧伤刺激通过下丘脑引起内分泌紊乱,这种紊乱与L—谷氨酸和L—天冬氨酸失控有关。  相似文献   
75.
刺激视上核对大鼠痛阈及电针镇痛的影响   总被引:2,自引:1,他引:1  
以钾离子透引起的大鼠甩尾反应为痛指标,观察了电和化学刺激视上核(SON)对大鼠痛阈(PT)和电针(EA)镇痛的影响。电刺激SON后,PT明显高于假刺激组(P<0.05~0.001),电刺激SON后电针足三里,镇痛效应明显提高,并有明显的量效关系。电刺激SON的近旁部位(0.5—1mm)对PT及电针镇痛无明显影响。SON内注射L-谷氨酸(L-Glu)后痛阈和电针镇痛效应都明显对照组,也有明显的量效关  相似文献   
76.
Electrostatic effects play an important role in protein interactions and may alter the biodistribution of antibodies. To study the effect of molecular charge on the biodistribution and infection imaging properties of human polyclonal immunoglobulin G (IgG), its iso electric point was varied by changing the level of diethylene triamine penta-acetic acid (DTPA) substitution: 0.8, 0.9, 3.7, 5.1 and 5.9 DTPA/IgG. Biodistributions of the different IgG preparations were determined at 10 min, 1, 6, 24, and 48 h post injection in normal rats, and infection imaging properties were determined in rats withEscherichia coli thigh infections. The biodistribution was significantly affected by pl. The immunoglobulin preparations with 0.9 and 3.7 DTPA/IgG showed faster clearance from the circulation and generally lower accumulation in most organs. The images had a target-to-background ratio of approximately 1.3–2.3:1. These results suggest that even though targeting is not affected by the level of DTPA substitutions, preparations with 0.9 and 3.7 DTPA/IgG may be superior imaging agents because of reduced accumulation by background organs.  相似文献   
77.
核酸原位杂交程序中探针和靶基因的加热变性和杂交为整个程序中最重要的环节,目前国内外最常用的方法是在切片上滴加DNA探针溶液后用盖玻片复盖组织,并加胶泥或其他封固剂封闭玻片四周,变性杂交后需拆除盖玻片,这一操作过程易损坏组织切片或出现干片、脱片。作者针对上述情况,对传统的核酸原位杂交方法中的部分程序加以改良,采用不加盖玻片直接在蒸汽中变性方法,经多次实验证明此方法稳定、可靠、简便,结果满意。  相似文献   
78.
胆汁酸对人红细胞膜脂质组分的影响及某些效应   总被引:2,自引:1,他引:1  
  相似文献   
79.
Background :
The aim of this study was to investigate the influence of osteoarthritis of lumbar vertebrae on serum bone formation and resorption marker levels of patients with benign prostatic hypertrophy (BPH).
Methods :
Serum levels of carboxyterminal propeptide of type I procollagen (PICP), alkaline phosphatase (ALP), carboxyterminaltelopeptide of type I collagen (ICTP), and prostate-specific antigen (PSA) were examined in 40 patients with BPH, and the presence of osteoarthritis at the lumbar vertebrae of the patients was evaluated by plain x-ray-p.
Results :
Findings of osteoarthritis were observed in 23 of the 40 patients (58%), and 10 of the patients had severe osteoarthritis (involving at least 2 lumbar vertebral bodies). The serum levels of PICP, ALP, ICTP, and PSA of the patients without osteoarthritis findings were not different from those of the patients with osteoarthritis or severe osteoarthritis.
Conclusion :
The influence of osteoarthritis on serum bone formation and resorption marker levels of patients with BPH appears to be rather slight, if there is any influence at all.  相似文献   
80.
Taurine is a β-aminosulfonic acid and is a ubiquitous amino acid whose role in the cochlea is not well established. In this study, its entry from blood into perilymph was investigated in the guinea pig as animal model. The penetration rate of [3H]taurine (molecular weight 125) into the perilymph of the scala vestibuli was measured 1 and 2 h after the intravenous infusion of [3H]taurine in nephrectomized animals. Results showed a rate of penetration in perilymph related to plasma at 36 ± 4.7% (n = 5) after 1 h and 43 ± 5.6% (n = 5) after 2 h. Compared to the penetration rate of urea (molecular weight 60) and mannitol (molecular weight 186) reported previously in rats, a passive entry of taurine into perilymph through the blood-perilymph barrier is suggested. Received: 30 July 1997 / Accepted: 15 January 1998  相似文献   
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