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21.
Spinocerebellar ataxia (SCA) types 2 and 3 are autosomal-dominant neurodegenerative disorders caused by mutations in two different genes. We identified mutations for SCA2 and SCA3 segregating simultaneously in a single Brazilian family. The index patient had SCA2, whereas her two second-degree cousins had SCA3. Disease was more rapidly progressive in the SCA2 patient, who presented severe brainstem and pancerebellar atrophy, as opposed to the two SCA3 patients, who had only mild cerebellar vermian atrophy. In such situations, molecular confirmation of all patients may avoid misdiagnosis of SCA subtypes and eventual errors in predictive testing of unaffected family members.  相似文献   
22.
目的评价NA:YAG激光虹膜切除术治疗原发性闭角型青光眼和葡萄膜炎继发青光眼的临床疗效。方法回顾分析192例219眼原发性闭角型青光眼和9例葡萄膜炎继发青光眼,接受NA:YAG激光虹膜切除术后的临床效果,随诊16—46月。结果激光切孔一次成功205眼(占89e),激光能量在11—17.1mJ,67%病例在22—84Mj,击射次数2-33次。葡萄膜炎继发青光眼9眼均二次激光后虹膜孔通畅。95.61%术后眼压正常,视野无变化,术后早期一过性眼压升高占34%,术中出血占36%,房角色素增加占47%,1例术后28月接受小量切除术,8例术后需配合使用降眼压药物控制眼压。结论NA:YAG激光虹膜切除术是一种治疗闭角型青光眼的安全有效的方法。术前掌握适应症,把握手术时机,充分的术前准备是手术成功的关键。  相似文献   
23.
Predictors of gastric emptying (GE) in patients with idiopathic Parkinson's disease (PD) of a solid and liquid meal are not well defined. For measurement of GE 80 patients with PD were randomly assigned to receive either a solid meal (250 kcal) containing 13C-octanoate (n = 40) or a liquid meal (315 kcal) with 13C-acetate (n = 40). All patient groups were off medication affecting motility and were matched for age, gender, body mass index, disease duration and severity, using Unified Parkinson's Disease Rating Scale (UPDRS). Gastric emptying was compared with a healthy control group (n = 40). Multiple regression analysis was used to determine predictors of gastric emptying. Exactly 88% and 38% of PD patients had delayed GE of solids and liquids respectively. Solid and liquid emptying was similar in women and men. There were no differences in GE in PD patients < 65 years of age when compared with patients > or = 65 years. Multiple regression analysis showed that motor handicaps such as rigour and action tremor are independent predictors of solid GE (r = 0.68, P < 0.001). The severity of motor impairment, but not any other neurological symptom, as assessed by UPDRS is associated with gastroparesis in PD and solid emptying is more likely to be delayed.  相似文献   
24.
肾移植术后并发尿路上皮肿瘤的临床分析   总被引:8,自引:0,他引:8  
目的 分析肾移植患者并发尿路上皮肿瘤的特点,探讨其诊治方法。方法 自1998~2003年肾移植患者1293例,术后发生尿路上皮恶性肿瘤21例(1.6%)。男4例,女17例。17例原发病为慢性问质性肾炎。发生尿路上皮肿瘤距肾移植6~62个月,平均26个月。其中膀胱癌6例,单侧肾盂或输尿管癌6例,单侧肾盂或输尿管、膀胱癌8例,双侧肾盂输尿管癌1例。10例上尿路肿瘤发生部位与移植肾同侧,4例发生于移植肾对侧。临床症状以无痛性肉服血尿和反复泌尿系感染为主。19例行手术治疗,术后所有患者免疫抑制剂用量减少1/3并辅以局部灌注化疗。结果 2例行姑息性治疗的晚期肿瘤患者分别于发现肿瘤5、8个月死亡。余19例现已随访2~5年。13例肿瘤复发,复发部位为膀胱或对侧原。肾、输尿管。所有患者在免疫抑制剂减量期间均未出现急性排斥。2例因切除移植肾恢复透析,17例肾功能正常。结论 慢性间质性。肾炎导致。肾功能衰竭的。肾移植患者和女性肾移植患者易发生移植后尿路上皮肿瘤;移植肾同侧上尿路较对侧好发肿瘤;对移植肾对侧为首发的上尿路发生肿瘤者可预防性行双侧上尿路根治性切除。  相似文献   
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Placenta is an important source of leptin during pregnancy that contributes to the high plasma leptin levels in pregnant women. Leptin and its functional receptors are synthesized in trophoblast cells that, in turn, secrete gestational hormones supporting a paracrine or autocrine role for leptin in the endocrine activity of the placenta. In the present study we examined the effect of leptin on in vitro release of gestational hormones (human chorionic gonadotropin (hCG), human placental lactogen (hPL), progesterone, estrogens and testosterone) by human term placental cells in culture. Placentas at term were obtained immediately after delivery from mothers with uncomplicated pregnancies. Progesterone, hCG, hPL, estradiol, estrone, estriol and testosterone levels were measured by different assays in culture media of cells maintained in monolayer culture after incubation for 12, 24, 48 or 72 h with leptin or placebo. Incubation with leptin did not modify hCG, hPL, progesterone, estriol and estrone secretion for any of the doses and times assayed. However, leptin led to a dose-dependent decrease in estradiol release. This effect was observed when treatment with recombinant human leptin spanned from 12 to 72 h. At this time an increase in testosterone levels was observed in leptin-treated cells versus placebo. These results indicate that leptin can be considered a gestational hormone implied in the endocrine function of the placenta, with an important role in control of the production of steroid reproductive hormones in placental cells in vitro.  相似文献   
28.
OBJECTIVES: To determine whether aromatase expression in the eutopic endometrium and adenomyotic foci is affected by previous use of oral contraceptives containing gestodene, and to determine whether changes in cyclooxygenase-2 (COX-2) expression occur in adenomyosis during the menstrual cycle. PATIENT AND METHODS: This was a retrospective cohort study carried out in paraffin-embedded endometrial tissue obtained from patients with a histological diagnosis of adenomyosis obtained during the proliferative (n = 25) and luteal (n = 10) phases of the menstrual cycle and following the use of continuous oral contraception with gestodene/ethinyl estradiol (n = 7). COX-2 and aromatase expression were measured in both eutopic endometrium and adenomyotic foci using immunohistochemical methods. RESULTS: Aromatase expression was detected in 80% of the endometrial slices by immunohistochemistry. In positive cases, aromatase was mainly detected in the stromal cells of the eutopic endometrium, whereas in the adenomyotic foci this expression was negative in the majority of the cases. Oral contraceptives containing gestodene, on the other hand, were effective in suppressing aromatase expression in both eutopic and ectopic endometrium. COX-2 expression was detected by immunohistochemistry in the glandular epithelium of both eutopic endometrium and adenomyotic foci and there were no significant changes in its intensity throughout the menstrual cycle. CONCLUSION: Aromatase expression in the eutopic endometrium and adenomyotic foci is suppressed by oral contraceptives containing gestodene. Increased aromatase activity may be responsible for the persistent COX-2 expression during the luteal phase.  相似文献   
29.
INTRODUCTION: Transesophageal echocardiography (TEE) has become increasingly useful in the study of patients with suspected pulmonary thromboembolism. OBJECTIVE: The aim of this study was to prospectively evaluate the usefulness of TEE in the study of the distal part of the left pulmonary artery (LPA) as well as the influence of this procedure on total echocardiographic exam duration. METHODOLOGY: A prospective study in two groups of consecutive patients referred for TEE with a one- year interval between evaluation of Group A: 33 patients, 17 male, mean age 54 +/- 24 years, and Group B: 42 patients, 20 male, mean age 48 +/- 27 years (p = NS). The procedure was considered long when it took more than 3 min to evaluate the distal part of the LPA. RESULTS: In group A we were able to visualize the distal part of the LPA in 24 patients (73%) without significant prolongation of total exam duration in 16 patients (48% of group A). In one of the patients with suspected pulmonary thromboembolism thrombi were only observed in the distal part of the LPA. In group B we were able to visualize the distal part of the LPA in 36 patients (86%) without significant prolongation of total exam duration in 26 patients (61% of group B). CONCLUSIONS: 1. Visualization of the distal part of the LPA was possible in more patients, and with TEE time prolongation in less patients, in group B. These differences can be accounted for by the training of the operator in this technique. 2. The importance of visualization of this part of the LPA in guiding treatment in the subset of patients with pulmonary thromboembolism confirms the usefulness of this specific procedure.  相似文献   
30.
Iron Fortification of Flours in Venezuela   总被引:1,自引:0,他引:1  
This paper reviews a conference about the impact of the iron fortification program in Venezuela; it was presented at the Pan American Health Organization regional technical meeting: "Iron Fortification: Where Are We in Terms of Iron Compounds," held in Washington January 10–12, 2001. Some of the data presented were published in the American Journal of Clinical Nutrition , including stimulating results about the impact of fortification of precooked corn and white wheat flours, as well as the prevalence of anemia and iron deficiency in the Venezuelan population. This article reports results from three surveys carried out in 1997, 1998, and 1999 on the same age and socioeconomic group that had been evaluated in 1990, 1992, and 1994. This article also shows the impact of iron fortification programs and the influence of other factors on the prevalence of iron deficiency and anemia during the last 7 years.  相似文献   
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