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991.
992.
993.
Modlin IM Latich I Zikusoka M Kidd M Eick G Chan AK 《Journal of clinical gastroenterology》2006,40(7):572-582
Carcinoid tumors are rare, often insidious neoplasms arising from neuroendocrine cells. The majority arise in the gastrointestinal system, and are often incidentally found during investigation, although some may present as an emergency bleed or perforation. The prosaic symptoms of flushing, diarrhea, and sweating are often overlooked; thus, the diagnosis is usually much delayed and the tumor is advanced at presentation. This diagnostic delay renders effective management difficult and adversely affects outcome. This overview provides a current assessment of the evolution of the diagnostic techniques available to establish an accurate biochemical (5-hydroxyindole-3-acetic acid and chromogranin A) and topographic diagnosis (octreoscan, radio-labeled metaidobenzylguanidine, computerized tomography, magnetic resonance imaging, positron emission tomography, enteroclysis, endoscopic ultrasound, enteroscopy, capsule endoscopy, and angiography) of carcinoid tumors. The utility and shortcomings of the respective modalities available are evaluated. Although considerable advances have been made in establishing the diagnosis of carcinoid tumors and in defining the topography of metastatic disease, the major limitation is the inability to establish an early and timely diagnosis before the advent of metastatic disease. 相似文献
994.
Moore DJ Masliah E Rippeth JD Gonzalez R Carey CL Cherner M Ellis RJ Achim CL Marcotte TD Heaton RK Grant I;HNRC Group 《AIDS (London, England)》2006,20(6):879-887
OBJECTIVE: To determine the association of markers of regional neurodegeneration (ND) at autopsy to degree of neurocognitive impairment in persons with HIV. DESIGN: In a prospectively followed cohort of HIV-infected individuals we examined the relationship between antemortem neuropsychological (NP) abilities and postmortem neuropathological data. METHODS: Twenty-seven HIV-infected individuals with both neuropsychological and neuropathological data were identified. Laser confocal scanning microscopy was used to determine the degree of ND based on: (1) microtubule-associated protein (MAP2; reflecting neuronal cell bodies and dendrites) and (2) synaptophysin (SYN; a measure of presynaptic terminals). A regional combined score, based on the distribution of percentage neuropil occupied by MAP2 and SYN and emphasizing severity of ND, was created for each brain region: midfrontal cortex, hippocampus, and putamen. RESULTS: The regional combined scores from each brain region studied were better correlated with level of global NP impairment than measures of SYN and MAP2 individually. In a regression, hippocampal and putamen regional combined scores were independent predictors of degree of antemortem NP impairment (F(3,23) = 6.17; P < 0.01; R2 = 0.45). The correlations among regional ND measures demonstrated that ND is unevenly distributed across multiple brain regions. CONCLUSIONS: As the anatomic distribution and temporal progression of neuropathologic changes appears to differ across individuals, it is important to consider both cortical and subcortical brain regions in studies of neuropathogenesis and treatment of HIV-related brain disease. Furthermore, combining information from several markers of neural injury provided the strongest association with degree of neurocognitive impairment during life. 相似文献
995.
Kravchick S Bunkin I Peled R Yulish E Ben-Dor D Kravchenko Y Cytron S 《Journal of endourology / Endourological Society》2007,21(10):1203-1206
BACKGROUND AND PURPOSE: Elevated PSA value in the presence of an indwelling catheter is still an enigma. The aims of this prospective study were: to investigate the reliability of elevated PSA levels in patients with normal DRE and indwelling catheter after AUR; to assess the impact of preoperative TRUS-biopsy in detecting prostate cancer in such circumstances; to estimate the crucial duration of follow-up period. PATIENTS AND METHODS: 63 patients were included in the study. PSA was assessed 5 days after catheter insertion. All patients failed to void without catheter and have been scheduled for surgery. TRUS-biopsy was performed before operation. All patients underwent surgery at least two weeks after prostate biopsies. Postoperative follow-up visits continued for at least 7 years. Biopsies were taken when indicated by persistently elevated PSA or an abnormal DRE. RESULTS: Mean PSA before catheter insertion differed significantly from PSA obtained on the 5(th) day after AUR (p = 0.001). Mean prostate volume calculated on TRUS was 80.5 +/- 28 ml. Mean duration of indwelling catheter placement was 37.8 +/- 7.97 days. Mean delay in operative treatment as a result of preoperative evaluation was 23.548 +/- 2.487 days. Carcinoma was detected in 13 patients, while clinically insignificant cancer was present in 31% (4 patients). It must be also emphasized that 38% of patients with carcinoma were >70 year-old. Preoperative TRUS-biopsy and postoperative pathologic exam diagnosed carcinoma in 5 patients (2 and 3 respectively). During 42 months of 7-year follow-up cancer was revealed in 8 patients. Mean PSA value in the follow-up period was significantly elevated in patients with carcinoma: 5.99 +/- 3.34 v/s 2.34 +/- 1.68 ng/ml (p = 0.007) and was the strongest predictor for cancer detection (p = 0.001). CONCLUSIONS: The detection rate of clinically significant cancer on preoperative biopsies postoperative pathologic exam in patients with AUR and indwelling catheter is low. These patients could be safely operated on without any delay. However, in order to detect clinically important cancer in the peripheral zone a postoperative monitoring period of should be recommended: starting 6 months after operation and continuing subsequently for at least 4 years. Postoperative PSA level is the strongest predictor of cancer detection and could be usefully employed in these patients. AUR and in the patients with large prostate cause elevated PSA. Cancer detection rate on preoperative biopsies is low in these patients. Long postoperative monitoring period should be strongly recommended. 相似文献
996.
Granberg CF Krambeck AE Leibovich BC Frank I Lohse CM Gettman MT Blute ML Chow GC 《Journal of endourology / Endourological Society》2007,21(10):1183-1186
BACKGROUND AND PURPOSE: After tumor morcellation, staging relies on clinical imaging. Our goal was to determine the size distribution of stage pT(3a) renal-cell carcinomas (RCCs) and whether evidence of extrarenal invasion is present on preoperative imaging. PATIENTS AND METHODS: We selected patients with organ-confined RCC treated surgically from 1975 to 2002 and subsequently found to have stage pT(3a) disease. Preoperative radiologic imaging reports were reviewed for evidence of extrarenal tumor extension. RESULTS: Of the 1781 patients treated surgically for pM(0) RCC, 129 (7.2%) had pT(3a) disease. Tumor size distributions were: 17 (13.2%) < or =4 cm, 38 (29.5%) >4 cm but < or =7 cm, and 74 (57.4%) >7cm. There were 6 patients (4.7%) with extrarenal extension according to preoperative imaging. Of these, 2 (5.3%) had tumors >4 cm but < or =7cm, and 4 (5.4%) had tumors >7 cm. CONCLUSION: Many pT(3a) tumors are small, and the majority is understaged clinically. Thus, morcellation in these patients would prevent accurate staging. 相似文献
997.
Lee C Weiland D Ryndin I Ugarte R Monga M 《Journal of endourology / Endourological Society》2007,21(9):957-960
PURPOSE: To evaluate the impact of the type of anesthesia on treatment efficacy, using a comparison of general anesthesia (GEN) and monitored anesthesia care with intravenous sedation (MAC), for patients undergoing extracorporeal shockwave lithotripsy (SWL) on the Medstone STS lithotripter. PATIENTS AND METHODS: A case-control study was conducted of 660 patients treated from 1986 to 2002. General anesthesia and MAC were utilized in 330 procedures each. Case matching was performed for stone size, stone location, and body mass index. All lithotripter units were staffed by a rotating schedule of the same 10 SWL-certified radiologic technicians. Patient characteristics, treatment parameters, complications, repeat procedures, and secondary procedures were recorded. Stone-free success rates (no residual fragments) were reported by the treating physician on the basis of plain radiographs. Chi-square analysis was used to compare patients in the two groups. RESULTS: The overall stone-free rate was better with GEN (67%) than MAC (55%; P = 0.04). Stone-free rates were not affected for stones 10 mm or in an upper calix. General anesthesia may decrease excursion of the calculus out of the focal area secondary to breathing or patient movement. 相似文献
998.
Thompson RH Blute ML Krambeck AE Lohse CM Magera JS Leibovich BC Kwon ED Frank I Cheville JC 《The American journal of surgical pathology》2007,31(7):1089-1093
Prior studies suggest that the renal sinus permits early tumor spread in otherwise localized renal cell carcinoma (RCC) tumors. We hypothesized that renal sinus fat invasion may be unrecognized in pT1 patients who subsequently die from RCC. Between 1985 and 2002, we identified 577 patients who underwent radical nephrectomy for localized pT1 clear cell RCC as reviewed by a single urologic pathologist (J.C.C.). Among these patients, 49 died from RCC including 33 who had their original nephrectomy specimen stored in formalin. These specimens were then resectioned with thin cuts of the renal sinus and reviewed by the same pathologist. For comparison, 33 patients who did not die from RCC (controls) also had their original nephrectomy specimen resectioned. Among the 33 patients who died from seemingly localized RCC, 14 (42%) had previously unrecognized renal sinus fat invasion compared with 2 (6%) of the controls (P<0.001). In addition, 19 (58%) patients who died from RCC had renal sinus small vein (microscopic venous) invasion, a pathologic feature not currently incorporated into the TNM staging system for RCC. This feature was present in 7 (21%) of the controls (P=0.003). In total, 22 (67%) patients who died from RCC had unrecognized renal sinus fat or small vein invasion compared with 7 (21%) of the controls (P<0.001). We conclude that renal sinus fat invasion is an important adverse pathologic feature that is clearly underreported in the literature. Appropriate assessment of nephrectomy specimens should include proper sampling of the renal sinus even for seemingly localized tumors. 相似文献
999.
1000.
Pereira JH Vasconcelos IB Oliveira JS Caceres RA de Azevedo WF Basso LA Santos DS 《Current drug targets》2007,8(3):459-468
Tuberculosis (TB) remains the leading cause of mortality due to a bacterial pathogen, Mycobacterium tuberculosis. However, no new classes of drugs for TB have been developed in the past 30 years. Therefore there is an urgent need to develop faster acting and effective new antitubercular agents, preferably belonging to new structural classes, to better combat TB, including MDR-TB, to shorten the duration of current treatment to improve patient compliance, and to provide effective treatment of latent tuberculosis infection. The enzymes in the shikimate pathway are potential targets for development of a new generation of antitubercular drugs. The shikimate pathway has been shown by disruption of aroK gene to be essential for the Mycobacterium tuberculosis. The shikimate kinase (SK) catalyses the phosphorylation of the 3-hydroxyl group of shikimic acid (shikimate) using ATP as a co-substrate. SK belongs to family of nucleoside monophosphate (NMP) kinases. The enzyme is an alpha/beta protein consisting of a central sheet of five parallel beta-strands flanked by alpha-helices. The shikimate kinases are composed of three domains: Core domain, Lid domain and Shikimate-binding domain. The Lid and Shikimate-binding domains are responsible for large conformational changes during catalysis. More recently, the precise interactions between SK and substrate have been elucidated, showing the binding of shikimate with three charged residues conserved among the SK sequences. The elucidation of interactions between MtSK and their substrates is crucial for the development of a new generation of drugs against tuberculosis through rational drug design. 相似文献