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Collagenous colitis is characterized by the presence of a thick subepithelial collagen band in the colonic mucosa. The condition was diagnosed on rectal biopsy in 10 patients (one male, nine females) who presented with watery diarrhoea. Although rectal mucosal erythema was present in three and ulceration in two, the mucosa was of normal endoscopic appearance in five of the patients. There was marked variability in the thickness of the submucosal collagen band, both between and within individuals. Empirical drug therapy included sulphasalazine, glucocorticoids and antidiarrhoeals. All patients reported symptomatic improvement.  相似文献   
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Two-dimensional HOHAHA and ROESY nuclear magnetic resonance techniques are used to obtain complete proton resonance assignments and to perform a conformational investigation of the neuropeptide neurotensin (pGlu-Leu-Tyr-Glu-Asn-Lys-Pro-Arg-Arg-Pro-Tyr-Ile-Leu) in aqueous solution, methanol, and membrane-mimetic [deuterated sodium dodecylsulfate (SDS)] environments. Results suggest the absence of discernible elements of secondary structure in water and methanol. ROESY spectra confirm that Lys-Pro and Arg-Pro peptide bonds are all-trans, but that a significant population of cis Arg-Pro bonds arises in aqueous solution, which increases in the environment of SDS micelles. The conformational ensemble of the peptide is observed to narrow as it becomes bound through its cationic mid-region to SDS micelles, with the accompanying advent of local extended structure. The overall results indicate the inherent conformational flexibility of neurotensin, and emphasize the environmental dependence of conformation in peptides of medium length.  相似文献   
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OBJECTIVE: Hemorrhage after tonsillectomy is a potentially lethal complication. Preoperative assessment consisting of prothrombin time (PT) and activated partial thromboplastin time (PTT) has been used to identify patients at risk for hemorrhage after tonsillectomy and adenoidectomy. We sought to assess the value of PT/PTT screening as a predictor of posttonsillectomy hemorrhage.DESIGN: A retrospective chart review was carried out with a minimum of 1 month follow-up.SETTING: Tertiary academic referral center.PATIENTS: Between January 1992 and June 1995, 382 patients undergoing tonsillectomy were examined; 339 patients with a minimum of 1 month follow-up were reviewed for this study.MAIN OUTCOME MEASURE: Normal and prolonged PT/PTT values were examined. Bleeding in the intraoperative, immediate postoperative, and delayed phases of healing was examined.RESULTS: Two-hundred and twenty-two patients had normal PT/PTT, 39 had prolonged PT/PTT, and 78 had no preoperative studies performed. Bleeding occurred in 2.7%, 2.6%, and 3.3%, respectively, of patients. Eight patients had positive family histories of bleeding tendencies. One patient [12.5%] with a normal PT/PTT experienced a delayed posttonsillectomy bleed. Of 39 patients with abnormal coagulation studies, 30 were borderline elevations with no repeat studies done; one patient experienced postoperative hemorrhage. Nine abnormal results were repeated; three returned to normal, three remained prolonged but underwent tonsillectomy with no intervention, and three received hematology consultations. One patient had lupus anticoagulant, one had Hageman Factor deficiency, and one was cleared for surgery with no diagnosis. All patients underwent tonsillectomy with no episodes of postoperative bleeding.CONCLUSIONS: Preoperative PT/PTT provides no additional information than does a bleeding history for the general pediatric population undergoing tonsillectomy. This should only be done in selective cases where warranted by history. (Otolaryngol Head Neck Surg 1997;117:628-32.)  相似文献   
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LONGEVITY AMONG ETHNIC GROUPS IN ALCOHOLIC LIVER DISEASE   总被引:1,自引:0,他引:1  
As part of a multicenter V.A. Cooperative Study, 437 male veteranswith varying stages of alcoholic liver injury were followedover a 4.5 year period. Their ethnic distribution consistedof 256 Caucasians, 109 black Afro-Americans, 63 Puerto RicanHispanics, and 9 Native American Indians. Survival analysesrevealed significant differences between groups (P = 0.0002):66% of Afro-Americans were still living at 42 months; Caucasianswere intermediate with 40% survival; and only 28% of Hispanicswere alive. The number of Native American Indians enrolled wastoo small to draw conclusions but none of those enrolled survivedbeyond 24 months. Survival regression analysis of 30 clinical,laboratory, histologic and nutritional parameters, revealedthe following significant risk factors: clinical severity (P< 0.0001), histologic severity (P < 0.0001), race (P =0.001), age (P = 0.002), BUN (P = 0.01) and ALT (P = 0.02).These analyses indicated that ethnicity, independent of othervariables, is significantly associated with outcome from thedisease.  相似文献   
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Immunoglobulin G, appearing after several months in the serum of a recipient of a successful kidney transplant from a closely matched sibling donor, was demonstrated to progressively inhibit unidirectional mixed lymphocyte cultures when donor lymphocytes were used either in responding or stimulating cell populations. The active recipient IgG had no effect in cultures in which donor cells were not used, nor did IgG obtained from other individuals show nonspecific inhibitory effects on cultures containing donor cells. It is suggested that the MLC inhibitory immunoglobulin may serve an immunoregulatory function after renal transplantation.  相似文献   
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Sulphasalazine is a commonly used second line agent in rheumatoidarthritis (RA) and other inflammatory joint diseases and isreported to be one of the least toxic of this group of drugs.Recently a severe allergic reaction and cases of lupus-likedisease have been described in patients with RA after treatmentwith sulphasalazine. We describe five patients, all with inflammatoryarthropathy who developed cutaneous vasculitis, lupus-like diseaseor atypical serology after exposure to sulphasalazine. Threeof four cases investigated were found to have the slow acetylatorphenotype. These reactions can complicate the diagnosis anddelay discontinuation of the drug. Moreover, present guidelinesfor the diagnosis of drug-induced lupus do not apply to themajority of patients with sulphasalazine-induced lupus. KEY WORDS: Sulphasalazine-induced lupus, Rheumatoid arthritis, dsDNA antibodies, Vasculitis  相似文献   
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