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81.
Pesticide-induced changes in peripheral thyroid hormone levels during different reproductive phases in Heteropneustes fossilis 总被引:1,自引:0,他引:1
Effects of gamma-BHC (an organochlorine) and malathion (an organophosphorus) exposure on plasma triiodothyronine (T3) and thyroxine (T4) levels have been studied in the freshwater catfish, Heteropneustes fossilis, during its annual reproductive cycle. After 4 weeks exposure of gamma-BHC (8 and 16 ppm) and malathion (10 and 20 ppm), the effects on plasma T3, T4, and T3/T4 ratio varied during different reproductive phases. Malathion seems to have a stimulatory effect, while gamma-BHC seems to have an inhibitory effect on extrathyroidal conversion of T4 to T3. Changes in levels of various thyroid hormones during different reproductive phases occurred most probably due either to inhibited (in response to gamma-BHC) or to stimulated (in response to malathion) extrathyroidal T4 monodeiodination and their altered excretion or consumption rate. 相似文献
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Autoimmune pancreatitis: imaging features 总被引:24,自引:0,他引:24
Sahani DV Kalva SP Farrell J Maher MM Saini S Mueller PR Lauwers GY Fernandez CD Warshaw AL Simeone JF 《Radiology》2004,233(2):345-352
PURPOSE: To retrospectively determine imaging findings in patients with autoimmune pancreatitis. MATERIALS AND METHODS: Twenty-nine patients (25 male and four female; mean age, 56 years; range, 15-82 years) with histopathologic diagnosis of autoimmune pancreatitis were examined. Data were reviewed by two radiologists in consensus. Imaging findings for review included those from helical computed tomography (CT), 25 patients; magnetic resonance (MR) imaging with MR cholangiopancreatography (MRCP), four patients; endoscopic ultrasonography (US), 21 patients; endoscopic retrograde cholangiopancreatography (ERCP), 19 patients; and percutaneous transhepatic cholangiography, one patient. Images were analyzed for appearances of pancreas, biliary and pancreatic ducts, and other findings, such as peripancreatic inflammation, encasement of vessels, mass effect, pancreatic calcification, peripancreatic nodes, and peripancreatic fluid collection. Follow-up images were available in nine patients. Serologic markers such as serum immunoglobulin G (IgG) and antinuclear antibody levels were available in 12 patients. RESULTS: CT showed diffuse (n = 14) and focal (n = 7) enlargement of pancreas. Seven patients had minimal peripancreatic stranding, with lack of vascular encasement, calcification, or peripancreatic fluid collection. Nine patients had enlarged peripancreatic lymph nodes. MR imaging showed focal (n = 2) and diffuse (n = 2) enlargement with rimlike enhancement in one. MRCP revealed pancreatic duct strictures in two and sclerosing cholangitis-like appearance in one. Endoscopic US showed diffuse enlargement of pancreas with altered echotexture in 13 patients and focal mass in the head in six. ERCP showed stricture of distal common bile duct in 12 patients, irregular narrowing of intrahepatic ducts in six, diffuse irregular narrowing of pancreatic duct in nine, and focal stricture of proximal pancreatic duct in six. Serologic markers showed increased IgG and antinuclear antibody levels in seven of 12 patients. At follow-up, CT abnormalities and common bile duct strictures resolved after steroid therapy in three patients. CONCLUSION: Features that suggest autoimmune pancreatitis include focal or diffuse pancreatic enlargement, with minimal peripancreatic inflammation and absence of vascular encasement or calcification at CT and endoscopic US, and diffuse irregular narrowing of main pancreatic duct, with associated multiple biliary strictures at ERCP. 相似文献
84.
Hamed Kargozaran MD Vu Vu BS Partha Ray MD Sanjay Bagaria MD Shawn Steen MD Xing Ye MS Singh Gagandeep MD 《Annals of surgical oncology》2011,18(2):345-351
Background
The efficacy of surgery for invasive mucinous neoplasms is unclear. We examined the natural history of invasive mucinous cystic neoplasms (MCN) and invasive intraductal papillary mucinous neoplasms (IPMN) in patients who underwent pancreatic resection.Methods
The Surveillance, Epidemiology, and End Results (SEER) database (1996–2006) was queried for cases of resected invasive MCN and IPMN. Demographics, tumor characteristics, and overall survival were examined using log-rank analysis and multivariate Cox regression model.Results
Of 185 MCN cases and 641 IPMN cases, 73% and 48%, respectively, were women (P < 0.0001). Most (73%) IPMN were in the head of the pancreas; most (64%) MCN were in the tail/body (P < 0.0001). Lymph node metastasis was more common for IPMN than MCN (46% vs. 24%, P < 0.0001). Overall survival after resection was better for patients with stage I MCN vs. stage I IPMN (P = 0.0005), and it was better for patients with node-negative MCN vs. node-negative IPMN (P = 0.0061). There was no significant difference in survival of patients with stage IIA MCN vs. stage IIA IPMN (P = 0.5964), stage IIB MCN vs. stage IIB IPMN (P = 0.2262), or node-positive MCN vs. node-positive IPMN (P = 0.2263). Age older than 65 years (hazards ratio (HR) 1.71, P = 0.0046), high tumor grade (HR 2.68, P < 0.0001), higher T stage (HR 2.11, P < 0.0001), and IPMN histology (HR 1.90, P = 0.0040) predicted worse outcome in node-negative patients.Conclusions
Our findings suggest that survival is better after resection of invasive MCN versus invasive IPMN when disease is localized within the pancreas, but this difference disappears in the presence of nodal metastasis or extrapancreatic extension. 相似文献85.
Yogeshkumar Nanasaheb Gavhane Adhikrao Vyankatrao Yadav 《Saudi Pharmaceutical Journal》2012,20(4):331-344
The aim of this review is to provide a broad perspective on intestinal absorption and the impact of intestinal first-pass metabolism on both clearance and drug–drug interaction prediction along with its historical perspectives. The review also considers abilities to bridge the gap between the increasing amount of intestinal in vitro data and the importance of intestinal first-pass metabolism in vivo. The significance of efflux transporters on the intestinal absorption is also discussed. 相似文献
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Morgan DJ Meddings J Saint S Lautenbach E Shardell M Anderson D Milstone AM Drees M Pineles L Safdar N Bowling J Henderson D Yokoe D Harris AD;the SHEA Research Network 《Clinical infectious diseases》2012,55(7):923-929
Background.?On 1 October 2008, in an effort to stimulate efforts to prevent catheter-associated urinary tract infection (CAUTI), the Centers for Medicare & Medicaid Services (CMS) implemented a policy of not reimbursing hospitals for hospital-acquired CAUTI. Since any urinary tract infection present on admission would not fall under this initiative, concerns have been raised that the policy may encourage more testing for and treatment of asymptomatic bacteriuria. Methods.?We conducted a retrospective multicenter cohort study with time series analysis of all adults admitted to the hospital 16 months before and 16 months after policy implementation among participating Society for Healthcare Epidemiology of America Research Network hospitals. Our outcomes were frequency of urine culture on admission and antimicrobial use. Results.?A total of 39 hospitals from 22 states submitted data on 2?362?742 admissions. In 35 hospitals affected by the CMS policy, the median frequency of urine culture performance did not change after CMS policy implementation (19.2% during the prepolicy period vs 19.3% during the postpolicy period). The rate of change in urine culture performance increased minimally during the prepolicy period (0.5% per month) and decreased slightly during the postpolicy period (-0.25% per month; P?.001). In the subset of 10 hospitals providing antimicrobial use data, the median frequency of fluoroquinolone antimicrobial use did not change substantially (14.6% during the prepolicy period vs 14.0% during the postpolicy period). The rate of change in fluoroquinolone use increased during the prepolicy period (1.26% per month) and decreased during the postpolicy period (-0.60% per month; P?.001). Conclusions.?We found no evidence that CMS nonpayment policy resulted in overtesting to screen for and document a diagnosis of urinary tract infection as present on admission. 相似文献
90.