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91.
92.
kDNA sequence homology of Leishmania donovani isolates from three types of kala-azar foci in China were analyzed by using dot and Southern hybridization with biotin- and 32P-labelled probes. The results revealed kDNA sequence heterogeneity among Leishmania donovani isolates from the three kala-azar foci: sequence homology between isolates of hill and desert foci was higher than that between hill and plain foci isolates. The kDNA hybridization technique was also found to be specific and sensitive for direct identification of Leishmania in animal tissues. In a preliminary survey, kDNA hybridization of cutaneous tissue blots of 71 dogs from endemic regions showed a positive rate of 40.8%, and the rate of double positive cases (touch blot hybridization and bone marrow smear) reached 91.3%. The direct identification of Leishmania in tissues by kDNA hybridization seems to be a useful and convenient method for epidemiological study and clinical diagnosis, especially for species/strain characterization.  相似文献   
93.
OBJECTIVE: To examine possible adverse effects on pituitary function of long-term administration of gonadotropin-releasing hormone agonist (GnRH-a). DESIGN: Prospective analysis of blood sampling before, during, and after GnRH-a therapy. SETTING: Tertiary institutional outpatient care. PATIENTS: Twelve normally ovulatory women with a diagnosis of endometriosis. INTERVENTIONS: Six-month suppression with GnRH-a. MAIN OUTCOME MEASURES: Serum levels of follicle-stimulating hormone, luteinizing hormone, free thyroxin index, cortisol (F), growth hormone (GH), prolactin (PRL), and thyroid-stimulating hormone (TSH). RESULTS: Basal and stimulated values of gonadotropins, PRL, F, TSH, and GH were normal and unchanged by 6 months of GnRH-a after resumption of menses. CONCLUSIONS: Utilizing dynamic pituitary function tests, we were unable to demonstrate an adverse effect of long-term GnRH-a therapy on pituitary function.  相似文献   
94.
使用围套式显微血管减压术治疗面肌痉挛50例。采用耳后斜行小切口,分离压迫血管后,用涤沦片包绕面神经根起始部并用银夹固定,术后49例痉挛停止。本法并发症少,无死亡。术后随访3个月至10年均无复发。根据术中发现将“责任血管”分为4型:接触型、压迫型、粘连包绕型和贯穿型。讨论了手术适应证、要求及并发症的预防等。  相似文献   
95.
Effective antitumor photodynamic therapy (PDT) may be related to damage of vasculature within the tumor. The purpose of this study was to determine if tumor cells secrete factors that stimulate proliferation of human umbilical vein endothelial cells (HUVEC) and result in enhanced sensitivity of HUVEC to aluminum-sulfonated phthalocyanine (AISPc)-PDT. Three human tumor cell lines—pharyngeal squamous carcinoma, colonic carcinoma, and mammary carcinoma—were used in this study. Co-culture of HUVEC and either squamous carcinoma or colonic carcinoma, but not mammary carcinoma, significantly increased HUVEC proliferation and AlSPc-PDT mediated cell damage. In addition, supernatant from squamous carcinoma and colonic carcinoma cultures also stimulated HUVEC proliferation and sensitivity to AISPc-PDT. Both supernatant and cell lysate from squamous carcinoma cells contained angiogenic factors consistent with basic and acidic fibroblast growth factors, as evidenced by Western blot analysis and BALB/c 3T3 fibroblast cell proliferation assays. Collectively, these results suggest that selected tumor cell lines produce angiogenic factors that induce HUVEC proliferation and subsequently enhance sensitivity to AISPc-PDT. © 1994 Wiley-Liss, Inc.  相似文献   
96.
Summary Using histochemical technique, the effects of radiofrequency catheter ablation (RFCA) on the activities of LDH, SDH, CCO, and Ca++-ATPase of guinea-pig ventricular myocytes were examined. The histological changes were observed for comparison. Radiofrequency energy (500 kHz) delivered was 20 WX 10 s. The results were as follows: RFCA resulted in significant impairments in all the four kinds of enzymes but without statistical differences in the areas involved in this energy level. No statistically significant difference was found between the ranges of enzymatic damages and areas of pathological lesions. These findings showed a consistency in areas of the histological and histochemical lesions resulted from RFCA.  相似文献   
97.
Sonic noise between 300 and 1600 Hz is introduced into the mouths of 11 healthy adult male subjects at resting lung volume and is detected over the anterior extrathoracic trachea and at three sites on the right posterior chest wall. To overcome the difficulties associated with non-parametric phase unwrapping due to thoracic anti-resonances, the pahse delay τ(f) of propagation between the trachea and the chest wall is estimated using a linear parametric ARX-type statistical model with the non-parametric magnitude spectra as a guide. The resulting τ(f) estimates are unambiguous and reliable, and show a clear trend of decreasing τ(f) with increasing frequency, indicating that sound at higher frequencies reaches the chest wall faster than that at lower frequencies. This finding indicates that respiratory sound transmission is highly dispersive, most probably owing to frequencydependent airway and parenchymal wavespeeds.  相似文献   
98.
Maternal corneal thickness during pregnancy   总被引:1,自引:0,他引:1  
We measured central corneal thickness in 89 pregnant women. It was increased 16 micron (P = .01) compared to the control eyes of 18 nongravid and 17 postpartum women. There was no significant difference (P = .79) in corneal thickness between the nongravid and postpartum groups. When comparing subjects by week of gestation, there was no trend over time in corneal thickness (analysis by linear regression). Intraocular pressure was lowered during pregnancy, but it did not correlate with corneal thickness for either the pregnant or nonpregnant group.  相似文献   
99.
100.
小肝癌的病理与螺旋CT诊断   总被引:7,自引:1,他引:6  
原发性肝癌(primaryhepatocellularcarcinoma,PH CC)在我国是居第3位的恶性肿瘤,每年患者达11万之多,预后甚差[1]。肝癌的早期诊断,是提高患者5年生存率的重要手段,也是影像学面临的重大课题。直径>3cm的病灶,各种影像学技术的检出敏感性均很高,无统计学差异。而对于小肝癌(SHCC),特别是微小肝癌(MHCC)的检出仍有一定困难,其检出敏感性有一定差异。以往文献报道术中超声、CT动脉门脉造影(CTAP)和碘油CT的敏感性最高,但均为创伤性检查,临床应用有严格指征。1989年螺旋CT机问世,其连续快速扫描和容积数据采集成像技术的应用,特别是近…  相似文献   
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