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71.
Fenarimol (alpha-(2-chlorophenyl)-alpha-(4-chlorophenyl)-5- pyrimidinemethanol a pyrimidine carbinol fungicide, caused a dose-related decrease in male fertility in Wistar rats. The effect was particularly evident in the anatomically normal progeny of dams treated with fenarimol throughout gestation and lactation. Based on the observation that the infertility was associated with the absence of vaginal sperm at the time of mating, the effect appeared to be the result of an absence of male sexual behavior. Fenarimol does not readily cross the placenta but does concentrate in milk, reaching three- to fivefold higher concentrations than those observed in the maternal plasma. These results suggest that fenarimol might be acting to block the perinatal development of male patterns of sexual behavior which involves the action of gonadal steroids within the central nervous system (CNS). To test this hypothesis, [14C]fenarimol was administered to dams and the radioactivity measured in the brains of the neonates. Radioactivity in the hypothalamus was three- to fourfold higher and the half-life four times longer than that observed in the remainder of the brain. Since the hypothalamus is believed to play a key role in the development and expression of male sexual behavior, it appears likely that fenarimol is acting centrally to decrease male sexual behavior, thereby decreasing male fertility.  相似文献   
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经肛门内镜显微手术切除直肠肿瘤   总被引:14,自引:3,他引:14  
目的评价经肛门内镜显微手术(TEM)切除直肠绒毛状腺瘤和早期直肠癌的应用效果。方法分析我院总结1995年11月至2001年12月27例TEM手术的临床资料。结果本组患者肿瘤直径中位值2.5cm,肿瘤下缘与齿状线距离(8.9±3.4)cm,肿瘤侵犯直肠周径范围(35.7±17.5)%。平均手术时间(109±46)min。平均住院日4.5d。无围手术期死亡。手术并发症有尿潴留、暂时性大便失禁和慢性阻塞性肺病(COPD)复发。术中2例切穿至腹腔,即刻内镜下修补成功。切缘100%瘤细胞阴性。病理示直肠绒毛状腺瘤14例、直肠腺癌13例,后者包括pTis2例,pT16例和pT25例。直肠癌腔内超声肿瘤T分期符合率为84.6%。5例pT2中2例中转前切除术,1例接受术后放疗,2例无附加任何治疗。平均随访18个月,所有病例无局部复发。死亡2例,但无复发迹象。结论TEM易行且安全,是直肠绒毛状腺瘤和部分T1直肠癌的治愈性手术,也可作为T2直肠癌的姑息性治疗手段。  相似文献   
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We hypothesized that neutrophil gelatinase-associated lipocalin (NGAL) is an early predictive biomarker of contrast-induced nephropathy (CIN). We prospectively enrolled 91 children (age 0–18 years) with congenital heart disease undergoing elective cardiac catheterization and angiography with contrast administration (CC; Ioversol). Serial urine and plasma samples were analyzed in a double-blind fashion by NGAL enzyme-linked immunosorbent assay (ELISA). CIN, defined as a 50% increase in serum creatinine from baseline, was found in 11 subjects (12%), but detection using increase in serum creatinine was only possible 6–24 h after CC. In contrast, significant elevation of NGAL concentrations in urine (135 ± 32 vs. 11.6 ± 2 ng/ml without CIN, p < 0.001) and plasma (151 ± 34 vs. 36 ± 4 without CIN, p < 0.001) were noted within 2 h after CC in those subjects. Using a cutoff value of 100 ng/ml, sensitivity, specificity, and area under the receiver-operating characteristic (ROC) curve for prediction of CIN were excellent for the 2-h urine NGAL (73%, 100%, and 0.92, respectively) and 2-h plasma NGAL (73%, 100%, and 0.91, respectively). By multivariate analysis, the 2-h NGAL concentrations in the urine (R 2 = 0.52, p < 0.0001) and plasma (R 2 = 0.72, p < 0.0001) were found to be powerful independent predictors of CIN. Patient demographics and contrast volume were not predictive of CIN.  相似文献   
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Studies on emotion processing in patients with temporal lobe epilepsy have dealt mainly with the processing of negative emotions. To further understand the neural basis of emotional disorders in temporal lobe epilepsy, we studied patterns of brain activation induced by implicit processing of negative and positive emotions perceived through facial expressions and emotionally salient stimuli in candidates for surgical treatment of intractable epilepsy. Using functional MRI, we compared, in patients with mesial temporal lobe epilepsy and healthy subjects, the patterns of brain activation elicited by the implicit processing of fearful, sad, and happy faces and pleasant and unpleasant scenes. The results revealed different patterns of activation in patients with left and right mesial temporal lobe epilepsy, compared with healthy subjects, suggesting that the left and right mesial temporal regions are involved differently in emotion processing, which could be related to different contributions in emotional arousal.  相似文献   
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The forearm is composed of the radial and ulnar shafts, which are linked by the interosseous membrane and intercalated between the elbow and wrist. The radius and ulna are connected by three joints, the proximal, middle, and distal radioulnar joints. The forearm ensures pronation/supination and longitudinal load transfer. The biomechanical and clinical relevance of the proximal and distal radioulnar joints is well established. In contrast, the middle radioulnar joint was considered relatively unimportant until studies published in the last decade showed that it fulfils crucial biomechanical functions and is of considerable clinical significance. We believe the conventional concept in which the forearm is viewed as part of either the elbow or the wrist is outdated and that a more relevant concept describes the forearm as a triarticular complex that functions as a full-fledged entity. In this concept, the three forearm radioulnar joints (proximal, middle, distal) work together to provide stability, mobility and load transfer. Here, we will argue for the relevance of the triarticular complex concept based on published data about forearm biomechanics and pathological conditions.  相似文献   
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