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排序方式: 共有6347条查询结果,搜索用时 15 毫秒
31.
PURPOSE: This is a retrospective study comparing the clinical data and morbidity of transperitoneal radical nephrectomy (TRN) and simple nephrectomy. MATERIAL AND METHODS: From 1st January, 1989 to 1st January, 1996 a total of 90 simple nephrectomies and from 1st January, 1996 to 1st August, 1999 a number of 85 TRN were performed at the Department of Urology of the Saint Stephen Hospital. The analysis of clinical data included operative time, length of analgesics, postoperative hospital stay and blood loss, as well as morbidity. RESULTS: The mean operative time for TRN was 170 min., being 95 min. for simple nephrectomy. The mean blood loss for TRN was 250 ml, and 400 ml for simple nephrectomy. There were different types of morbidity for TRN and simple nephrectomy. The complications of TRN mean minimal risk and easy correctibility. CONCLUSION: Our results demonstrate an overall clear advantage of TRN when compared to simple nephrectomy. 相似文献
32.
PURPOSE: To investigate the effect of prior anesthesia on the time to full cycloplegia in young Chinese subjects. METHODS: The amplitude of accommodation was monitored over a 50-minute interval after the application of 1% cyclopentolate hydrochloride with a pretreatment of 0.4% benoxinate (oxybuprocaine) or 0.9% saline solution (control). Using a nonlinear mathematical model, the rate of accommodative loss (k) and the time required for 95% of total cycloplegia (T95%) were determined. RESULTS: Statistical analysis revealed a significantly faster rate of accommodative loss (P < .0001) after prior anesthesia (0.129 +/- 0.05) compared with the controls (0.103 +/- 0.04). T95% was noted at 26.43 +/- 10.22 minutes after prior anesthesia, which was significantly shorter (P < .0001) than that after the saline treatment (35.28 +/- 16.51 minutes). CONCLUSIONS: Prior application of topical anesthetic can shorten the time to full cycloplegia for people, such as the Chinese, with dark irides. 相似文献
33.
34.
Nancy Young MD Tam Nguyen MD Richard Wiet MD FACS 《Operative Techniques in Otolaryngology》2003,14(4):263-267
Cochlear implants are the single greatest advancement of the late 20th century for the deaf and hearing impaired. Recent expanding guidelines as well as surgical techniques are discussed. Cochlear implantation is currently the only means to restoring partial hearing to patients with severe-to-profound sensorineural loss not aidable with conventional amplification. 相似文献
35.
S. S. Wijesinha B. L. Atkins N. E. Dudley P. K. H. Tam 《Pediatric surgery international》1998,13(2-3):146-148
A prospective study of 25 boys who underwent circumcision for medical reason was performed. Specimens of periurethral bacterial
flora were taken before operation as well as 3 weeks after surgery, so that each boy acted as his own control. Before circumcision,
13 (52%) harboured uropathogenic organisms (Escherichia coli and other coliforms, Enterococcus spp, Proteus spp, Pseudomonas spp, and Klebsiella spp); after circumcision, none of the boys had uropathogens, the only organisms cultured from the periurethral region being
skin commensals. We postulate that circumcision converts a ‘cul-de-sac' that is a reservoir of organisms capable of causing
ascending urinary tract infection into a surface colonised by natural skin organisms. This study provides circumstantial evidence
supporting the idea that circumcision in well-selected patients may confer protection from urine infection.
Accepted: 15 March 1997 相似文献
36.
Gábor RÉPÁssy Csaba Forster-HorvÁth Attila JuhÁsz Róza ÁDÁny Anna TamÁssy József TÍmÁr 《Pathology oncology research : POR》1998,4(1):14-21
Twelve laryngeal squamous cell carcinoma cases (7 laryngeal and 5 hypopharyngeal cancer; 15 samples) were analysed by immunohistochemistry
for the expression of invasion markers CD44v6/v3, NM23 and matrix metalloproteinase, MMP2. The laryngeal epithelium showed
CD44v6+v3+NM23- /MMP2- phenotype. When tumors were grouped into TNM categories the phenotype of the T2 and T3 tumors was similar, characterised
by decreased CD44v3+ and lack of MMP2 expressions. Meanwhile the NM23 expression was more frequent in T3 tumors. In T4 stage the frequency of
NM23 and MMP2 positive cases increased (5/6 and 4/6, respectively) but there was no correlation with the appearence of lymph
node metastasis. Comparison of the phenotype of laryngeal and hypopharyngeal tumors, irrespective of the TNM stages, revealed
characteristic differences: T2 stage laryngeal tumors showed decreased CD44v3 and occasional NM23 and MMP2 positivity, while
in T3 stage these tumors were characterised by increased frequency of NM23 positivity. The phenotype of the hypopharyngeal
tumors was significantly different with a high frequency of MMP2 positive cases (5/6) and NM23+1ow CD44v3+ phenotype. The sharp differences in the phenotypes of laryngeal and hypopharyngeal carcinomas were connected to the differences
in their invasive capacity unlike to the size of the tumors, since the T4 stage hypopharyngeal tumors had a significantly
smaller size than laryngeal ones, even at lower stages.
This work was supported by the Hungarian Ministry of Welfare: ETT No: T-11-100/93 相似文献
37.
38.
Kanter KR Erez E Williams WH Tam VK 《The Journal of thoracic and cardiovascular surgery》2000,120(5):885-890
OBJECTIVE: Recurrent aortic narrowing after repair of aortic coarctation or interrupted aortic arch, as well as diffuse, long-segment aortic hypoplasia, can be difficult to manage. Extra-anatomic ascending aorta-descending aorta bypass grafting through a sternotomy is an alternative approach for this problem. METHODS: Since 1985, 19 patients aged 2 months to 18 years (mean 10.7 years) underwent extra-anatomic bypass with 10- to 30-mm Dacron grafts. The initial diagnosis was coarctation with hypoplastic arch in 15, interrupted aortic arch in 3, and diffuse long-segment aortic hypoplasia in 1. Seventeen of the children had a total of 22 previous operations: transthoracic interposition or bypass graft (n = 7), end-to-end anastomosis (n = 7), subclavian arterioplasty (n = 6), and synthetic patch (n = 2). The mean time from initial repair was 8.0 years (range 0.6-18 years). Three children had previous sternotomies. Cardiopulmonary bypass was avoided in all but 6 patients (5 with simultaneous intracardiac repairs). RESULTS: No hospital or late deaths occurred. On follow-up from 4 months to 14.7 years (mean 7.9 years), no reoperations for recurrent stenosis were performed. Two patients have arm-to-leg pressure gradients: 20 mm Hg at rest in 1 patient and a 60-mm Hg systolic exercise gradient with no resting gradient in the other. One patient required exclusion of an aortic aneurysm at the old coarctation repair site 13 years after extra-anatomic bypass. Three children had subsequent successful cardiac operations. CONCLUSIONS: Extra-anatomic bypass is an effective and relatively easy approach for selected cases of complex or reoperative aortic arch obstruction. It should be considered as an alternative operative technique for complex aortic arch reconstruction. 相似文献
39.
40.
H S Brar S L Kjos W Dougherty Y S Do H B Tam W A Hsueh 《American journal of obstetrics and gynecology》1987,157(2):363-367
Since pregnancy-induced hypertension is associated with impaired uteroplacental blood flow, we studied fetoplacental and maternal renin production in controls and subjects with pregnancy-induced hypertension. We measured total, active, and inactive (pro-) renin in maternal serum, fetal arterial and venous blood, and chorion homogenate in eight normotensive term patients and 18 patients with pregnancy-induced hypertension. No differences in active or prorenin were found in maternal blood from normal women or patients with pregnancy-induced hypertension. In contrast, fetal artery and vein, as well as chorionic tissue, contained significantly higher active renin in pregnancy-induced hypertension compared with normal subjects. No difference in fetal or chorionic prorenin was seen in the two groups. Thus active to total renin ratio was higher in the fetus and chorion of subjects with pregnancy-induced hypertension, which suggests enhanced active renin production. These results suggest that pregnancy-induced hypertension is associated with increased activity of the renin-angiotensin system in the fetoplacental unit, which is not reflected in the maternal circulation. This may be an attempt by the fetus and chorionic membranes to maintain vascular homeostasis in the face of altered uteroplacental blood flow. 相似文献