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CHARLES STEADMAN CLINTON TEAGUE PAUL KERLIN OWEN HARRIS KEVIN HOURIGAN JOHN SAMPSON 《Journal of gastroenterology and hepatology》1987,2(5):459-466
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
3.
ALAIN DIMEGLIO YANN PHILIPPE CHARLES JEAN-PIERRE DAURES VINCENZO DE ROSA BONIFACE KABORE 韩岳 《骨科动态》2006,2(1):35-41
背景:Sauvegrain方法是通过分析肘部X线片来评估骨龄,常用于青春期生长发育最为迅速的两年间的骨龄测定。本文旨在研究该方法的准确性以及在小儿骨科中的应用价值。
方法:Sauvegrmn法主要评估肘部的4个解剖标志点:外髁、肱骨滑车、尺骨鹰嘴突以及桡骨近端骨骺。它是一个27分制的评分系统。对上述结构所得的评分进行合计而得出一个总分,然后使用标准图表确定骨龄。让三位观察者分别利用该方法进行骨龄评估。三位观察者通过分析60个男孩和60个女孩样本左肘部的前后位和侧位X线片来测定骨龄,并将该结果与通过分析左手和腕部后前位X线片的Greulich和Pyle图谱而得出的骨龄结果进行比较。间隔4周后每个观察者再测定骨龄一次。
结果:通过分析肘部X线片的方法测定骨龄更为精确,因为采用该方法测定骨龄可以精确到半岁。根据观察者的评定,Sauvegrain法显示出很好的观察者之间的相关性(r=0.93)和可重复性(r=0.96)。Sauvegrain法与Greulich和Pyle图谱之间有很好的相关性(r=0.85)。然而,一些肘部生长中心显示出一种中间的发育形态,这种形态学不适合Sauvegrain法的评分。这就导致了数据分析时出现误差。我们建议对于这些样本设定中间评分,并且通过修改原始图表而使评分更为精确。
结论:改良的Sauvegrain法简单、可靠而且可重复性高,它补充了Greulich和Pyle图谱的不足。在临床实践中,骨骼成熟度可以通过骨龄、年生长率以及第二性征而得以很准确的评估。因此,当青春期需要进行骨骺或脊柱关节融合术时,这种方法对于确定手术时间具有重要意义。
可信水平:诊断性研究,Ⅱ级,进一步可信度参见作者介绍。 相似文献
4.
An experimental model for canine visceral leishmaniasis 总被引:6,自引:1,他引:5
PEDRO ABRANCHES GABRIELA SANTOS-GOMES NURIT RACHAMIM† LENEA CAMPINO LIONEL F. SCHNUR‡ CHARLES L. JAFFE† 《Parasite immunology》1991,13(5):537-550
Seven mixed-breed dogs were challenged with either promastigotes or amastigotes of Leishmania donovani infantum strains recently isolated from naturally infected dogs. Different routes and numbers of parasites were utilized and each dog was monitored for at least 1 year post-infection. Anti-parasite specific antibody levels were measured by enzyme-linked immunosorbence, immunofluorescence, crossed-immune electrophoresis and Western blotting on crude antigen. Western blotting on two pure parasite proteins, dp72 and gp70-2, was also done. Mitogenic and antigen-specific stimulation of peripheral blood lymphocytes was monitored; and the haematological, clinical and parasitological parameters measured. Dogs challenged with amastigotes exhibited a more pronounced humoral response to leishmanial antigens. Only in one case was strong antigen-specific proliferation detected. Clinical signs of disease, including hypergammaglobulinaemia, enlarged lymph nodes and the presence of parasites, were also more apparent in the dogs challenged with amastigotes. None of the seven dogs died. Serum antibodies to leishmanial antigens were apparent between 1.5 to 3 months following challenge and correlated with the appearance of enlarged lymph nodes, hypergammaglobulinaemia and the presence of parasites in tissue biopsies. Serum antibodies remained chronically high in these dogs throughout the period of the study. Only one dog (1/3) challenged intravenously with promastigotes and the dog challenged intradermally with amastigotes produced transient antibody responses to leishmanial antigen. 相似文献
5.
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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R.CHARLES HOWELLS II MD MARK K. WAX MD HASSAN H. RAMADAN MD 《Otolaryngology--head and neck surgery》1997,117(6):628-632
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
9.
ARTHUR J. FARKAS JOHN P. PIERCE SHU-HONG ZHU BRADLEY ROSBROOK ELIZABETH A. GILPIN CHARLES BERRY ROBERT M. KAPLAN 《Addiction (Abingdon, England)》1996,91(9):1271-1280
Prospective data from the California Tobacco Surveys (n=2066) were used to perform a critical test of the Prochaska et al. (1991) stages of change model. When the stages of change model was used as a stand alone predictor, smokers in preparation at baseline were more likely to be in cessation at follow-up than smokers in pre-contemplation at baseline (OR adj="1.9)" When stage membership was combined with baseline measures of addiction including smoking behaviors and quitting history, it was not a significant predictor of future cessation. A prediction equation that combined daily vs. occasional smoking, cigarettes per day smoked, life-time quits of at least a year, and quits of more than 5 days in the previous year discriminated smokers in cessation at follow-up of 1 to 2 years better than did the stages of change model. The area under the ROC curve for the equation based on addiction measures was 69.3% vs. 55.1% for the stages of change. Cessation rates ranged from 7.7% to 35.7% for the four-category addiction equation compared with 15.1% to 24.9% for stages of change model. 相似文献
10.
SHORT ROBERT D.; JOHANNSEN FREDERIC R.; ULRICH CHARLES E. 《Toxicological sciences》1988,10(3):517-524
A 6-Month Multispecies Inhalation Study with Maleic Anhydride.SHORT, R. D., JOHANNSEN, F. R., AND ULRICH, C. E. (1988). Fundam.Appl. Toxicol. 10, 517524. This study was initiated toassess the safety of atmospheres containing maleic anhydride.Accordingly, rats (15/sex/group), hamsters (15/sex/group), andmonkeys (3/sex/group) were treated 6 hr a day 5 days a weekfor 6 months. Atmospheres were generated by subliming maleicanhydride and were monitored using Tenax collection columnsand gas chromatography to detect total maleic; i.e., maleicanhydride plus maleic acid. The mean analytical concentrationswere 0, 1.1,3.3, and 9.8 mg/m3 of total maleic. Dose-relatedsigns of nasal and ocular irritation were observed at each testlevel in all three species; signs included discharge, sneezing,gasping, and coughing. No significant treatment-related mortalitywas observed in any species. While reduced weight gains wereobserved only in mid- and high-dose rats, their terminal bodyweights were greater than 90% of control values. No treatment-relatedeffects were observed in hematology. clinical chemistry, urinalysis,and pulmonary function tests. Although microscopic evaluationof tissue revealed evidence of nasal irritation in all species,there was no evidence of systemic toxicity which was directlyattributed to maleic anhydride. While the results of this studysupport the current ACGIH TLV and OSHA PEL of 1 mg/m3 regardingsystemic toxicity, continuous exposure at this level duringthe day may produce some signs of irritation. 相似文献