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111.
BACKGROUND: This study was carried out to evaluate whether bilateral orchidopexy represents a poor or good prognostic factor in azoospermic men undergoing testicular sperm extraction (TESE). METHODS: One hundred and seven presumed non-obstructive azoospermia (NOA) patients, according to conventional clinical parameters (volume of testis, FSH, clinical history) were submitted to testicular biopsy with TESE. Thirty men (28%) had a history of bilateral orchidopexy for cryptorchidism. RESULTS: Normal spermatogenesis or mild hypospermatogenesis was diagnosed in 12/30 ex-cryptorchid patients and in 7/77 presumed NOA patients (P = 0.0004). Conversely, pure Sertoli cell-only syndrome or complete maturation arrest was found in 10/30 ex-cryptorchid patients and in 48/77 presumed NOA patients (P = 0.0094). In 53/107 patients (49.5%), TESE allowed a positive sperm retrieval. At least one spermatozoon was observed in 22/30 ( approximately 73%) ex-cryptorchid patients and in 31/77 ( approximately 40%) presumed NOA patients (P = 0.0026). A large number of spermatozoa (equivalent to an obstructive pathology) were retrieved in 13/30 ex-cryptorchid and in 10/77 presumed NOA patients (P = 0.001). A history of bilateral orchidopexy in presumed NOA patients correlates positively for the chance of retrieving testicular spermatozoa (odds ratio 3.8; 95% confidence interval 1.41-10.21; P = 0.008). CONCLUSIONS: Although bilateral cryptorchidism is usually considered a testicular secretive dysfunction, TESE permits retrieval of a large number of spermatozoa in almost 40% of cases. Our data suggest the existence of congenital or acquired obstructive anomalies of the seminal ducts in azoospermic orchidopexed men.  相似文献   
112.
Effects of oestradiol (E2) have been studied on the in vitro T cell-dependent differentiation of B cells from peripheral blood and spleen using normal donors and patients with the antibody deficiency disease CVID. We also studied whether it modifies T cell DNA synthesis. The effect of E2 was examined on cultures of B cells with T cells for IL-2-driven immunoglobulin secretion or of T cells for phytohaemagglutinin (PHA)-driven DNA synthesis. Interestingly, in control experiments without E2, the normal sex difference in immunoglobulin production is reversed in CVID. The data show that for normal individuals there is no major difference between male and female donors in the in vitro actions of E2 on blood B and T lymphocytes. With normal blood B cells, E2 failed to affect IgM production, but it did inhibit IgG. In normal splenic cells, E2 increased both IgM and IgG secretion in a similar way to the tonsillar cell data previously reported. E2 on normal blood T cell DNA synthesis was stimulatory. With blood cells from CVID patients an interesting contrast was seen. As with normal B cells, E2 had no effect on IgM secretion by those CVID blood B cells able to secrete IgM. However, a difference between patients and normals was that E2 did not inhibit the IL-2-driven IgG production by those CVID B cells able to secrete IgG. For T cell function, the stimulatory effect of E2 on CVID T cell DNA was as in normal T cells. However, E2 failed to restore CVID B and T cell function to normal levels. These data suggest that there may be subtle defects in the pathway of action of E2 in CVID lymphocytes.  相似文献   
113.
114.
胆总管的矢状断层解剖研究   总被引:1,自引:0,他引:1  
刘树伟  王凡 《解剖学杂志》1993,16(5):391-394
在30套成人腹部连续矢状断层标本上,胆总管与下腔静脉主要出现于R2-R3断层;胆总管胰腺段与胰头的关系有部分包埋,完全包埋及胰腺后型;十二指肠大乳头集中出现于R3断层;胆总管的行程有4种形式。文内还探讨了矢状断层里胆总管各段的毗邻及识别标志。  相似文献   
115.
Thyroglossal duct cysts are common congenital abnormalities or developmental field defects, usually detected in early childhood. Despite their frequent occurrence, familial patterns are rare. We report on two new families with thyroglossal duct cysts. In the first family three siblings were involved, while in the second one, father and son were affected. This trait may be autosomal recessive or possibly multifactorial, as the first family would indicate, and also autosomal dominant, as the second family would suggest.  相似文献   
116.
动脉导管溶栓治疗急性肢体动脉栓塞14例分析   总被引:3,自引:0,他引:3  
目的 探讨动脉导管溶栓治疗急性肢体动脉栓塞的方法和疗效。方法回顾性分析14例肢体动脉栓塞的诊断方法和介入手术治疗方案。结果治愈11例,治愈率78.6%(11/14);2例好转。无患肢缺血坏死或截肢,无术后因肾功能衰竭死亡。结论动脉导管溶栓是治疗急性肢体动脉栓塞有效的方法,值得进一步开展和探索。  相似文献   
117.
The mechanisms of virus-induced airway hyperresponsiveness in asthma and allergy and the failure of host defence in patients suffering from secondary airway infections are still largely unknown. The aim of this study was to examine whether the presence of allergic rhinitis or susceptibility to recurrent sinusitis affects the structural and cellular changes in nasal mucosa during natural colds and convalescence. We compared the mucosal changes in biopsy samples during acute natural colds (days 2-4 of illness) and convalescence (3 weeks later) in patients with allergic rhinitis (n = 9), patients with susceptibility to sinusitis (n = 19) and healthy controls (n = 20). We saw similarly increased numbers of mucosal T and B lymphocytes and mast cells and increased vascular density during the acute colds compared to convalescence in all the three groups. The allergic subjects had elevated levels of eosinophils in the acute phase (P = 0.03), and the allergic and sinusitis-prone subjects had elevated levels of epithelial T cells (P = 0.04) and low levels of mast cells (P = 0.005) in convalescence compared to the control group. The sinusitis-prone subjects lacked intraepithelial cytotoxic cells in convalescence. In the allergic subjects, the reticular basement membrane was thicker in the acute phase compared to the convalescence (P = 0.05). These results suggest that various cells of the airways, including inflammatory and structural cells, are involved during viral respiratory infections in subjects with allergic rhinitis. The small numbers of mast cells and cytotoxic lymphocytes in the sinusitis-prone subjects may be related to their susceptibility to bacterial complications.  相似文献   
118.
在78具成年尸体上详细观察了髂总动脉的分支。髂总动脉外侧支的出现率为30.76%,多起于髂总动脉远侧1/3段(43.33%),始端外径为2.38±0.06(0.90~4.20)mm.起自髂总动脉的髂腰动脉的出现率为10.26%,也多起于髂总动脉远侧1/3段,其始端外径为3.03±0.14(2.50~3.80)mm。记录了此两支动脉的走行和分布,并讨论了它们的临床意义。  相似文献   
119.
Restoration of bile flow after 9-day cholestasis in rat liver normalized the content of lipid peroxidation products. The removal of the cholestatic factor after 12-day cholestasis was not followed by recovery of these parameters. We showed that measurement of serum concentration of lipid peroxidation products in patients with cholelithiasis during the preoperative period holds promise for selection of the optimum time for surgical treatment and prediction of the risk of postoperative complications. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 145, No. 1, pp. 39–42, January, 2008  相似文献   
120.
The triggering of the TCR/CD3 complex by anti-CD3 (OKT3) antibody leads to the formation of T cell clusters. In cultures of T lymphocytes from most normal individuals, the peak of cluster formation occurs at 24 h, but with cells from patients with common variable immunodeficiency (CVI) it was seen earlier at 4-9 h; in addition, the clusters were larger than normal, particularly at 9 h. Cluster formation by CVI and normal cells was dependent on temperature and divalent cations, but did not require Fc receptors. Since OKT3 clustering is known to be dependent on the LFA-1/ICAM-1 adhesion system, the effect of monoclonal antibodies directed against these molecules was tested. A potent inhibitor was the antibody against the common beta chain of the integrin family (CD18), but of four MoAbs against the alpha chains (CD11), three inhibited and one stimulated T cell aggregate formation. Increased expression of LFA-1 or ICAM-1 on CVI patients' T cells could not be demonstrated. The accelerated clustering was therefore probably due to an increase in the proportion of cells carrying the activated form of LFA-1. The formation of large numbers of homotypic lymphocyte clusters might reduce the effective interaction between B and T cells, thus contributing to the depression of immunoglobulin synthesis observed in this disease.  相似文献   
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