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71.
Intravascular catheters are inserted into almost all critically ill patients. This review provides up-to-date insight into available knowledge on epidemiology and diagnosis of complications of central vein and arterial catheters in ICU. It discusses the optimal therapy of catheter-related infections and thrombosis. Prevention of complications is a multidisciplinary task that combines both improvement of the process of care and introduction of new technologies. We emphasize the main component of the prevention strategies that should be used in critical care and propose areas of future investigation in this field.  相似文献   
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Metabolic Brain Disease - The night shift paradigm induces a state of chronic partial sleep deprivation (CPSD) and enhances the vulnerability to neuronal dysfunction. However, the specific neuronal...  相似文献   
75.
The objective of this article is to review the available literature on the epidemiology, predisposing factors, and conditions associated with primary gallbladder cancer, and to discuss the role of prophylactic cholecystectomy in high-risk patient populations. Gallbladder cancer is a highly malignant tumor with a poor 5-yr-survival rate. It is a tumor of the elderly and has striking genetic, racial, and geographic characteristics, with an extremely high prevalence in Native Americans and Chileans. Cholelithiasis is a well-established risk factor for gallbladder cancer and the risk seems to correlate with stone size. Polyps that are >1 cm, single, sessile, and echopenic are associated with a higher risk of malignancy. Anomalous junction of pancreaticobiliary ducts (AJPBD), especially without choledochal cyst, and porcelain gallbladder are additional factors that predispose to gallbladder cancer. Lesser associations include chronic bacterial infections of the gallbladder, typhoid carrier state, certain occupational and environmental carcinogens, hormonal changes in women, and certain social, dietary, and familial factors. It is important to identify high-risk groups for gallbladder cancer because of the dismal nature of this tumor. In patients with porcelain gallbladder and anomalous junction of the pancreatic and biliary ducts, cholecystectomy is recommended provided that the patient is a good operative candidate. Patients with large solitary polyps or gallstones require close ultrasonic follow-up. With the advent of endoscopic ultrasound it is expected that early changes of malignancy in polyps will be reliably detected, and more patients will potentially be cured with a simple cholecystectomy. Through a MEDLINE/PAPERCHASE search we identified and reviewed articles regarding gallbladder cancer published in English-language journals between 1966 and 1999, using the key words biliary tract and gallbladder diseases, cancer, neoplasms, surgery, cholelithiasis, gallstones, cholecystitis, gallbladder polyps, risk factors, chemical industry, occupational diseases, typhoid, porcelain gallbladder, bacteremia, and precancerous conditions. We also used the bibliography of relevant articles to increase our search. A total of 122 publications were selected using the mentioned data source.  相似文献   
76.
Radiofrequency ablation is the treatment of choice for patients with Wolff-Parkinson-White syndrome and symptomatic tachyarrhythmias. The technique involves localising the pathway with multiple catheters at various sites followed by radiofrequency energy application at that site. Single catheter approach has been described for ablation of manifest left-sided accessory pathways. In this article, we report the ablation of accessory pathways in different locations in patients with Wolff-Parkinson-White syndrome by using a two-catheter approach. Twenty-three consecutive patients with symptomatic Wolff-Parkinson-White syndrome were taken up for radiofrequency ablation with this approach. Pathways could be successfully ablated in 11 out of 13 patients with left free wall, 5 out of 7 with right posteroseptal, one patient of left posteroseptal and each of the 2 patients of right mid septal locations giving an overall success in 19/23 (82.6%) patients. Hence, two-catheter approach can be used safely to ablate accessory pathways in different locations with high success rate, thus minimising the procedure time associated with conventional approach.  相似文献   
77.
Methotrexate (MTX) is among the best-tolerated disease-modifying antirheumatic drugs for the treatment of rheumatoid arthritis (RA); major drawbacks of MTX therapy are the large interpatient variability in clinical response and the unpredictable appearance of a large spectrum of side effects. Several studies have demonstrated gene polymorphism that may regulate intracellular methotrexate metabolic pathway enzymes linked to drug efficacy and safety, but the evidence available is not yet conclusive. We decided to run a pilot study to determine the incidence of Methylene tetrahydrofolate (MTHFR; C677T, A1298C) and Thymidylate synthase (TS; 5′ UTR repeat, 3′ UTR deletion) gene polymorphism in rheumatoid arthritis patients in our community (Indian Asian) and further explore its association with MTX response (efficacy, toxicity). Thirty-four naïve RA patients on supervised MTX therapy and 139 healthy controls were genotyped for A1298C and C677T polymorphism of the MTHFR gene and 5′ UTR repeat and 3′ UTR deletion polymorphism of the TYMS gene by polymerase chain reaction-restriction fragment length polymorphism. Association, if any, between gene polymorphism and MTX response in RA patients was analyzed. The MTHFR A1298C ‘C’ allele incidence among RA patients (46%) was significantly higher (χ 2?=?4.24, P?相似文献   
78.
BACKGROUND: An attempt was made to induce aortoarteritis in mice by using various antigens. METHODS AND RESULTS: The Swiss mice were immunized with eight different antigens and were grouped A to G. Group H served as control. The mice were then bled at 1st, 2nd, 4th, 6th and 8th month interval post-immunization for estimating antibody titer. Then the mice were sacrificed and the heart, aorta and kidney were taken out and processed for hematoxylin-eosin staining. There was gradual increase in the antibody titer from 1st month till 4th month within all the experimental groups (A-G), when compared with control group H. The titer started falling sharply from 6th month post-immunization. However, the control group H did not show much variation. When each individual group was compared separately with control group H, the significant statistical value was obtained. Histopathological examination revealed mild inflammation (+) in kidney by 2nd month, moderate inflammation (++) by 6th month, extensive inflammation (+++) by 8th month and alteration in the normal parenchyma of kidney by 8th month. CONCLUSIONS: The histopathological changes brought out through antigens were more pronounced by 8th month following injection of tunica media, tunica adventitia, tunica intima and aorta collagen as compared to that of standard collagen and mouse aorta injections.  相似文献   
79.
Previous reports have emphasized the association of primary hepatocellular carcinoma in patients with idiopathic hemochromatosis with cirrhosis. In contrast, patients with idiopathic hemochromatosis without cirrhosis have no increased risk of hepatocellular carcinoma. Phlebotomy therapy, by preventing the accumulation of parenchymal iron and subsequent cirrhosis, is believed to prevent hepatocellular carcinoma in the precirrhotic stage of the disease. We report the case of a 67-yr-old man with a 32-yr history of idiopathic hemochromatosis complicated by cirrhosis, who had reversal of cirrhosis with phlebotomy therapy, yet developed hepatocellular carcinoma. There was no serologic or tissue evidence of hepatitis B infection.  相似文献   
80.
Women with polycystic ovary syndrome (PCOS) undergoing ovulation induction appear to be extremely sensitive to gonadotropin stimulation and at increased risk for ovarian hyperstimulation syndrome. To determine granulosa cell responsiveness to recombinant human FSH (r-hFSH), dose-response studies were conducted in 16 individual PCOS patients and 7 normal women. Each subject received an iv injection of r-hFSH at doses of 0, 37.5, 75, or 150 IU in a randomized fashion on four separate occasions. Blood samples were obtained at frequent intervals before and for 24 h after r-hFSH administration for measurement of gonadotropins and steroid hormones. Our results showed that administration of r-hFSH produced instantaneous and equivalent dose-related increases in serum FSH in PCOS and normal women, which were followed by similar exponential decreases to baseline levels within 24 h in both groups. In PCOS subjects, the peak mean incremental response of serum estradiol (E(2)) to 150 IU of r-hFSH was 1.8-fold greater (P < 0.0001) and considerably accelerated compared with that found in normal women. In contrast, E(2) responses to 37.5 IU and 75 IU were similar between groups. Regression analysis of maximal E(2) concentrations in response to r-hFSH in each individual subject revealed that the slope of the linear trend line in the group of women with PCOS (r = 0.82) was significantly greater (P < 0.01) than that of normal controls (r = 0.71). The time-course of response revealed that in PCOS women, increases of E(2) were not sustained, compared with those of normal controls, because peak concentrations were followed by an estimated 40% decrement in circulating levels, whereas E(2) levels in normal women persisted for 24 h after reaching maximal values. These findings indicate that women with PCOS exhibit a significantly greater capacity for E(2) production in response to iv r-hFSH, compared with normal women. In PCOS, E(2) production was relatively transient because after peak concentrations a marked decline was detected at each dose, unlike normal women who exhibited persistent elevations of E(2) for up to 24 h. That this distinction was dose-dependent supports the concept of an FSH dose-response threshold, beyond which PCOS but not normal women are susceptible to ovarian hyperresponsiveness.  相似文献   
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