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排序方式: 共有4951条查询结果,搜索用时 31 毫秒
91.
PM Christiansen N Boye T Steiniche J Weeke P Wara 《Canadian Metallurgical Quarterly》1998,160(39):5645-5647
In the period February 1994 to November 1995 11 laparoscopic adrenalectomies were performed at our institution (seven women, four men). A transperitoneal approach was used in both right- and left-sided operations. Results were collected retrospectively. Indications for surgery were: Conn's syndrome (four), Cushing's syndrome (two), phaecromocytoma (four), and incidentaloma (one). The operations took median 170 minutes (range 105-250 minutes). Median size of the tumour was 4 cm range 1(1/2)-5 cm). No significant peri- or postoperative complications were recorded. The patients were discharged from the surgical unit median two days after surgery. Laparoscopic operation emerges as an alternative to open operation when dealing with smaller adrenal tumours. Because of the small number of patients, these operations have to be restricted to a few centres where both internists, anaesthesiologists and surgeons with expertise in this field are found. 相似文献
92.
OBJECTIVE: To characterize the biochemical mechanisms of expression of the pyruvate dehydrogenase (PDH) E1alpha subunit exon 10 R302C missense mutation. BACKGROUND: Mutations in the X-linked E1alpha subunit gene are responsible for most cases of PDH deficiency, an important cause of neurodevelopmental defects and neurodegeneration with primary lactic acidemia. Although the disease shows extreme allelic heterogeneity, the R302C mutation has been defined in several unrelated cases. METHODS: Cell lines expressing selectively either the mutant or wild-type E1alpha alleles against identical genetic backgrounds were generated from the fibroblasts of a female heterozygous for the R302C mutation. Enzyme activity, mRNA, polypeptide expression, and turnover were studied in each. RESULTS: The residual PDH activity was below measurable levels in the cell line (B5) expressing only the mutant allele and normal in the wild-type polypeptide expressing (A10) cell line, confirming that the R302C mutation alone is sufficient to cause a severe PDH deficiency. The mutant polypeptide was less stable than the wild-type polypeptide, but the steady-state level of the mutant E1alpha protein was reduced only two- to threefold. CONCLUSIONS: The primary mechanism of expression of the R302C mutation must be limitation of catalytic efficiency. We speculate that catalysis may be inhibited in the mutant polypeptide because conformational changes are induced near serine 300, a residue that is particularly important as a regulatory phosphorylation site in the wild-type polypeptide. 相似文献
93.
S Chang SL Parker T Pham AU Buzdar SD Hursting 《Canadian Metallurgical Quarterly》1998,82(12):2366-2372
BACKGROUND: Little is known about the cause of inflammatory breast carcinoma (IBC), the most aggressive form of breast cancer. To the authors' knowledge, no studies have investigated whether IBC risk factors are different from those for breast carcinoma overall, and there has been only one report of IBC incidence and survival patterns. METHODS: The authors used data from the Surveillance, Epidemiology, and End Results program of the National Cancer Institute for the period 1975-1992 to calculate age-adjusted incidence and survival rates for 913 white and 121 African American women with IBC involving dermal invasion of lymphatic ducts and 166,375 white and 13,674 African American women with other types of breast carcinoma (non-IBC). RESULTS: Between 1975-1977 and 1990-1992, IBC incidence doubled, increasing among whites from 0.3 to 0.7 cases per 100,000 person-years and among African Americans from 0.6 to 1.1 cases. However, rates for African Americans varied due to the small numbers of IBC cases. The twofold increase in IBC incidence was higher than that observed for non-IBC during the same period (27% for African Americans and 25% for whites). IBC patients were significantly younger at diagnosis than non-IBC patients; and among both IBC and non-IBC patients, African Americans were younger than whites. Overall survival was significantly worse for IBC patients than for non-IBC patients and for African Americans than for whites. Among whites, 3-year survival improved more for IBC patients than for non-IBC patients between 1975-1979 and 1988-1992, increasing from 32% to 42% for IBC patients (P=0.0001) and from 80% to 85% for non-IBC patients (P=0.0001). CONCLUSIONS: The disparities observed in incidence trends and age at diagnosis, particularly according to race, highlight the need for further investigation of the differences between IBC and non-IBC incidence. 相似文献
94.
The purpose of this study was to compare probing depth resolution achieved by gingivectomy and periodontal flap techniques in the treatment of cyclosporine A- and nifedipine-induced gingival enlargement. Ten kidney transplant patients who were receiving cyclosporine A and nifedipine for at least 6 months participated in the study. Five patients were randomly assigned to the gingivectomy group and 5 patients to the periodontal flap group. Only anterior segments of the oral cavity (canine to canine) were surgically treated. Clinical measurements, including probing depths, plaque index, and gingival sulcus index, were taken at baseline, 6 weeks, 6 months, and 1 year. Results showed that probing depths, while similar for both groups in the first 6 weeks of the study, were significantly shallower for the periodontal flap group when compared to the gingivectomy group at 6 months (2.48 +/- 0.34 mm versus 4.87 +/- 0.79 mm, respectively) and 1 year (322 +/- 0.65 mm versus 6.40 +/- 1.02 mm, respectively). Within its limitations, this study suggests that the pocket reduction achieved by the periodontal flap may be sustained for longer periods of time than by the gingivectomy technique in the treatment of cyclosporine A- and nifedipine-induced gingival enlargement. 相似文献
95.
96.
AS Stein MR O'Donnell A Chai GM Schmidt A Nademanee PM Parker EP Smith DS Snyder A Molina DE Stepan R Spielberger G Somlo KA Margolin N Vora J Lipsett J Lee J Niland SJ Forman 《Canadian Metallurgical Quarterly》1996,14(8):2206-2216
PURPOSE: To evaluate in a prospective study the efficacy of autologous bone marrow transplantation (BMT) in adult patients with acute myelogenous leukemia (AML) in first remission, using a single course of high-dose Cytarabine (HD Ara-C) consolidation therapy as in vivo purging. PATIENTS AND METHODS: Sixty consecutive adult patients with AML in first complete remission (CR) were treated with HD Ara-C consolidation therapy as a method of in vivo purging before marrow collection. High-dose therapy consisted of fractionated total-body irradiation (FTBI) 12 Gy, intravenous etoposide 60 mg/kg, and cyclophosphamide 75 mg/kg, followed by reinfusion of cryopreserved marrow. RESULTS: Sixty patients underwent consolidation treatment with HD Ara-C with the intent to treat with autologous BMT. Sixteen patients were unable to proceed to autologous BMT (10 patients relapsed, one died of sepsis, one developed cerebellar toxicity, two had inadequate blood counts, and two refused). Forty-four patients underwent autologous BMT and have a median follow-up time of 37 months (range, 14.7 to 68.7) for patients who are alive with no relapse. The cumulative probability of disease-free survival (DFS) at 24 months in the intent-to-treat group is 49% (95% confidence interval [CI], 37% to 62%) and in those who actually underwent autologous BMT is 61% (95% CI, 46% to 74%). The probability of relapse was 44% (95% CI, 31% to 58%) and 33% (95% CI, 20% to 49%) for the intent-to-treat and autologous BMT patients, respectively. CONCLUSION: This approach offers a relatively high DFS rate to adult patients with AML in first CR. The results of this study are similar to those achieved with allogeneic BMT. 相似文献
97.
Except for subjective clinical criteria, there is no formal definition of distal radius fracture instability in the literature. The purposes of this ex vivo biomechanical study were (1) to provide an objective mechanical definition of fracture instability and (2) to demonstrate a noninvasive method that allows for direct measurement of instability. The following 3 questions are addressed: (1) Can the stability of distal radius fractures be measured using computed tomography (CT)? (2) Are the stability measurements reproducible? (3) How does external fixation change stability? A CT technique is described that was used to measure displacement of fracture fragments and measure the compliance of ex vivo distal radius fractures before and after external fixation. Validation studies of the CT technique revealed a mean coefficient of variation of 0.38. There was a linear relationship between measured and known displacements for all 3 orthogonal planes (coefficient of determination 0.99; p < .01). There was significant fracture displacement with loads as small as 20 N. The slope of the load-displacement curve (structural compliance) provided a quantitative measure of fracture instability. Fracture compliance decreased up to 69% after application of an external fixator. 相似文献
98.
Hemoptysis secondary to an aortobronchial fistula is rare and uniformly fatal when left untreated. The authors describe a case of massive hemoptysis caused by an aortopulmonary fistula in an infected Dacron graft used successfully to repair a coarctation of the aorta. 相似文献
99.
Standard procedures for estimating factor scores for the Wechsler Adult Intelligence Scale—Revised (WAIS—R; D. Wechsler, 1981) involve equally weighted sums of the subtests that load most highly on the factor being estimated. We argue that factor scores derived in this manner lack discriminant validity; they are strongly biased toward g (the first unrotated factor) and away from the other 2 unrotated factors. If regression-like weights are applied to all of the WAIS—R subtests and the products are summed, the resulting differentially weighted factors give results that show similar convergent validity and much greater discriminant validity with respect to the original factors. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
100.
Factors associated with cumulative trauma disorders (CTDs) of the upper extremities were studied retrospectively, using data from three apparel manufacturing plants in the southeastern United States. Reported CTDs among the employees at risk during fiscal years 1991 and 1992 were analyzed focusing on individual and plant variables. Results showed that CTD rates increased from 1991 to 1992 and fluctuated in a cyclical pattern each year, peaking during January, March, and August. Employee age and duration of employment were associated with CTD rates. Employees aged 45 to 49 had higher CTD rates than those in any other age groups. Employees with 1 to 3 years' experience had higher CTD rates than employees with more years of service. 相似文献