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排序方式: 共有647条查询结果,搜索用时 15 毫秒
1.
An external audit of laparoscopic cholecystectomy performed in medical treatment facilities of the department of Defense. 总被引:1,自引:1,他引:0 下载免费PDF全文
OBJECTIVE: This study provided an objective survey by an outside auditing group of a large, complete patient population undergoing laparoscopic cholecystectomies, determined the frequency of complications, especially bile duct injuries, and presented a system for classifying and comparing the severity of bile duct injuries. SUMMARY BACKGROUND DATA: This is the first study of laparoscopic cholecystectomy to encompass a large and complete patient population and to be based on objectively collected data rather than self-reported data. The Civilian External Peer Review Program (CEPRP) of the Department of Defense health care system conducted a retrospective study of 5642 patients who underwent laparoscopic cholecystectomies at 89 military medical treatment facilities from July 1990 through May 1992. METHODS: The study sample consisted of the complete records of 5607 (99.38%) of the 5642 laparoscopic cholecystectomy patients. RESULTS: Of the sample, 6.87% of patients experienced complications within 30 days of surgery, 0.57% sustained bile duct injuries, and 0.5% sustained bowel injuries. Among 5154 patients whose procedures were completed laparoscopically, 5.47% experienced complications. Laparoscopic procedures were converted to open cholecystectomies in 8.08% of cases. Intraoperative cholangiograms were attempted in 46.5% of cases and completed in 80.59% of those attempts. There were no intraoperative deaths; 0.04% of the patients died within 30 days of surgery. CONCLUSIONS: The frequency of complications found in this study is comparable to the frequency of complications reported in recent large civilian studies and earlier, smaller studies. The authors present a system for classifying bile duct injuries, which is designed to standardize references to such injuries and allow for accurate comparison of bile duct injuries in the future. 相似文献
2.
Acute appendicitis: CT and US correlation in 100 patients 总被引:19,自引:1,他引:18
3.
Perforated colorectal neoplasms: correlation of clinical, contrast enema, and CT examinations 总被引:2,自引:0,他引:2
Hulnick DH; Megibow AJ; Balthazar EJ; Gordon RB; Surapenini R; Bosniak MA 《Radiology》1987,164(3):611-615
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm. 相似文献
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The yield of flexible fiberoptic sigmoidoscopy in the detection of asymptomatic colorectal neoplasia
Recent evidence of a reduction in mortality rates from distal colorectal cancers in populations screened by rigid sigmoidoscopy suggests that further benefits may be achieved by the use of fiberoptic sigmoidoscopy as the screening modality. However, there is limited evidence as to the expected yield of neoplasia using the standard 60-cm instrument. The aim of this study was to determine the yield of neoplasia in an asymptomatic population in the at-risk age group undergoing fiberoptic sigmoidoscopy.Recruitment into the screening program was among State Department personnel. In total, 4,216 asymptomatic subjects (50–65 years) were offered flexible sigmoidoscopic screening performed following a simple enema bowel preparation. Those in whom a neoplastic condition was identified underwent further investigation (colonoscopy or barium enema).Of those offered screening 4,005 (95%) underwent the examination. Eleven carcinomas were detected at flexible sigmoidoscopy and two carcinomas were detected at further investigation in subjects with rectosigmoid polyps. The overall detection rate of carcinomas was 3.2 per 1,000 subjects screened.Histologically proven adenomas were detected in 217 subjects, 5.4% of the population screened.In this cohort of individuals flexible sigmoidoscopy appears to have been an acceptable form of screening.The detection rate of neoplasia, particularly colorectal adenomas, is higher than that reported from studies of fecal occult blood screening. 相似文献
6.
Steenbergen EJ; Verhagen OJ; van Leeuwen EF; van den Berg H; von dem Borne AE; van der Schoot CE 《Blood》1995,86(2):692-702
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL. 相似文献
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Sequence comparison of human and yeast telomeres identifies structurally distinct subtelomeric domains 总被引:6,自引:2,他引:6
Flint J; Bates GP; Clark K; Dorman A; Willingham D; Roe BA; Micklem G; Higgs DR; Louis EJ 《Human molecular genetics》1997,6(8):1305-1313
We have sequenced and compared DNA from the ends of three human
chromosomes: 4p, 16p and 22q. In all cases the pro-terminal regions are
subdivided by degenerate (TTAGGG)n repeats into distal and proximal sub-
domains with entirely different patterns of homology to other chromosome
ends. The distal regions contain numerous, short (<2 kb) segments of
interrupted homology to many other human telomeric regions. The proximal
regions show much longer (approximately 10-40 kb) uninterrupted homology to
a few chromosome ends. A comparison of all yeast subtelomeric regions
indicates that they too are subdivided by degenerate TTAGGG repeats into
distal and proximal sub-domains with similarly different patterns of
identity to other non-homologous chromosome ends. Sequence comparisons
indicate that the distal and proximal sub-domains do not interact with each
other and that they interact quite differently with the corresponding
regions on other, non- homologous, chromosomes. These findings suggest that
the degenerate TTAGGG repeats identify a previously unrecognized,
evolutionarily conserved boundary between remarkably different subtelomeric
domains.
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