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41.
A 74-year old man underwent a radical cholecystectomy for presumed gallbladder cancer. The histology of the resected specimen in fact revealed the lesion to be metastatic renal cell carcinoma from his resected right nephrectomy performed 14 years previously.  相似文献   
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The guinea pig model of tuberculosis is used extensively in different locations to assess the efficacy of novel tuberculosis vaccines during pre-clinical development. Two key assays are used to measure protection against virulent challenge: a 30 day post-infection assessment of mycobacterial burden and long-term post-infection survival and pathology analysis. To determine the consistency and robustness of the guinea pig model for testing vaccines, a comparative assessment between three sites that are currently involved in testing tuberculosis vaccines from external providers was performed. Each site was asked to test two "subunit" type vaccines in their routine animal model as if testing vaccines from a provider. All sites performed a 30 day study, and one site also performed a long-term survival/pathology study. Despite some differences in experimental approach between the sites, such as the origin of the Mycobacterium tuberculosis strain and the type of aerosol exposure device used to infect the animals and the source of the guinea pigs, the data obtained between sites were consistent in regard to the ability of each "vaccine" tested to reduce the mycobacterial burden. The observations also showed that there was good concurrence between the results of short-term and long-term studies. This validation exercise means that efficacy data can be compared between sites.  相似文献   
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Peripheral action of opioids for pain control, for which local inflammation has been shown to be crucial, is being increasingly used in clinical practice. The aim of this study was to evaluate the hypothesis that addition of fentanyl to lidocaine, when injected into inflamed dentoalveolar tissues, can improve the quality of analgesia during surgery. Seventy-one patients reporting with pain and tenderness in the maxillary tooth were assigned into the experimental (LAF) or control (LA) group in a prospective, randomized double-blind trial. The LAF group (n = 36) was injected submucosally with a mixture of 40 microg of fentanyl (0.8 ml) and 2% lidocaine hydrochloride with 1:200000 adrenaline (2 ml). In the LA group (n = 35) 0.9% of saline (0.8 ml) was added instead of fentanyl. The pain scores were recorded before injecting, 5 min after injection, and immediately after surgery using a visual analogue scale. The mean pain scores were not significantly different at all time intervals. Twelve patients in the LAF group (2.75+/-0.72 ml) and ten patients in the LA (2.90+/-0.70 ml) group required additional local anaesthetic to achieve pain control. In conclusion, there was no improvement in quality of intraoperative analgesia on addition of fentanyl to lidocaine in inflamed dentoalveolar tissues.  相似文献   
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Charache  S; Dover  GJ; Moyer  MA; Moore  JW 《Blood》1987,69(1):109-116
Five patients with sickle cell anemia were treated with hydroxyurea (HU), in hopes of augmenting their production of fetal hemoglobin. Laboratory responses in two patients treated for more than 2 years were encouraging and there were suggestions of clinical improvement. Long- term HU therapy should be considered for severely affected adults with sickle cell anemia who are willing to accept what is probably a small risk of carcinogenesis. Preliminary chromosomal analysis and knowledge of the clastogenic properties of HU suggest that conception and pregnancy should be avoided. Pharmacokinetic studies will probably be necessary to adjust individual dosage schedules so that cytotoxicity is avoided. F cell responses can be seen in 2 to 3 weeks if the HU dose is optimal, but establishment of a large number of F cells in the circulation may take a month or longer.  相似文献   
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PurposeWe have assessed the hypothetical impact of guideline-concordant osteoporosis screening on baseline behaviors utilizing two different guidelines and determined the relative ability of each to identify osteoporosis treatment candidates.MethodsWe conducted secondary analyses from the Fracture Risk Perception Study, which enrolled patients aged 50 to 75 years to complete questionnaires about their bone health. We determined our baseline screening rates and detection of treatment candidates and then assessed the hypothetical impact of adherence to U.S. Preventive Services Task Force (USPSTF) and National Osteoporosis Foundation (NOF) criteria, particularly for women aged 50 to 64.ResultsOf 144 women aged 50 to 64 years screened, 14 (9.7%) were treatment candidates. Screening based on identification of one or more risks (NOF) would lead to testing of 102 of the 144 patients (71%) to identify 12 of 14 treatment candidates (86%). Applying USPSTF criteria (9.3% FRAX threshold) would test 45 of the same 144 women (31%) to identify 11 of 14 treatment candidates (79%). NOF risk-based criteria would result in a moderate absolute screening rate reduction (16%, p = .0011; 95% CI, 7%–25%), but only marginal improvement in identifying treatment candidates (odds ratio, 2.67; 95% CI, 0.57–12.47). Applying the more selective USPSTF criteria greatly reduced unnecessary testing (56% absolute screening rate reduction; p < .0001; 95% CI, 47%–64%) while further improving the odds of identifying treatment candidates (odds ratio, 10.35; 95% CI, 2.72–39.35).ConclusionsWhen contemplating screening younger patients, systematic calculation of FRAX and ordering only when the 9.3% fracture risk threshold is reached may decrease unnecessary screening for many women while still identifying appropriate osteoporosis treatment candidates.  相似文献   
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