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71.
Thirty-three human studies concerned with antimicrobial prophylaxis in obstetric-gynecologic surgery were analyzed, with particular attention to experimental design. Eighty-two percent of the studies were prospective, 70% randomized and 39% double-blind. Patients were stratified according to underlying disease in 15%, complications of prophylaxis were mentioned in 61% of the studies, and statistical analysis was done in 55% of the studies. There was considerable variation in antibiotics employed and in the types of infection encountered. Twenty-seven of the 28 papers published after 1966 advocated prophylaxis. In contrast, less than two thirds of the papers concerned with general surgery support the use of perioperative prophylactic antibiotics. Despite some variability in methodology and antibiotic agents used, there is little controversy among the studies analyzed. 相似文献
72.
Tyrer P Cooper S Crawford M Dupont S Green J Murphy D Salkovskis P Smith G Wang D Bhogal S Keeling M Loebenberg G Seivewright R Walker G Cooper F Evered R Kings S Kramo K McNulty A Nagar J Reid S Sanatinia R Sinclair J Trevor D Watson C Tyrer H 《Journal of psychosomatic research》2011,71(6):392-394
Objectives
To determine the prevalence of significant health anxiety (hypochondriasis) in patients aged 16–75 in cardiology, respiratory medicine, neurological, endocrine and gastrointestinal clinics in general hospitals in London, Middlesex and North Nottinghamshire.Method
The Health Anxiety Inventory (HAI) (short form) was administered to patients attending the five clinics over a 21 month period and all those who scored 20 or more invited to take part in a further assessment for a randomised controlled trial.Results
Of 43,205 patients attending the clinics 28,991 (67.1%) were assessed and of these, after exclusion of ineligible patients 5747 (19.8%) had significant health anxiety. 444 subsequently agreed to take part in a randomised controlled trial of treatment. The prevalence levels varied by clinic with neurology (24.7%) having the highest prevalence followed by respiratory medicine (20.9%), gastroenterology (19.5%), cardiology (19.1%), and endocrinology (17.5%).Conclusion
Abnormal health anxiety is common and a significant problem in those attending medical clinics and deserves greater awareness. 相似文献73.
Stromal tumors of uncertain malignant potential (STUMPs) are rare tumors characterized by an atypical, unique stromal proliferation of the prostate. Various stromal proliferations of STUMPs have been described; however, epithelial proliferations occurring within the STUMP have not been systematically described to date. We reviewed 89 cases of STUMP from our consultation service from 1990 to 2010. Nineteen cases without a glandular component were excluded. We next evaluated the glandular component of the remaining 70 cases of STUMP for glandular crowding and complexity, prostatic intraepithelial neoplasia (PIN), squamous metaplasia, urothelial metaplasia, basal cell hyperplasia, adenosis, and clear cell cribriform hyperplasia. In 58 cases (83%), the glandular component differed from glands on the same biopsy specimen uninvolved by STUMP. The most common abnormalities were glandular crowding in 35 of 70 (50%) and a very prominent basal cell layer in some glands in 32 of 70 (46%) cases. The next most frequent glandular variation from normal was prominent papillary infolding in 13 of 70 (19%) cases. Less-frequent epithelial changes within the STUMP were as follows: 10 of 70 (14%) showed cystically dilated glands; 7 of 10 (10%) had basal cell hyperplasia; 6 of 70 (9%) had urothelial metaplasia; 6 of 70 (9%) showed squamous metaplasia; 3 of 70 (4%) had cribriform hyperplasia; 3 of 70 (4%) had adenosis; and 1 case each showed high-grade PIN, low-grade PIN, and partial atrophy. The glandular component of STUMP was histologically normal in 12 (17%) cases. There was a tendency toward urothelial and squamous metaplasia in STUMPs with a phyllodes pattern, and a prominent basal cell layer in STUMPs with degenerative and cellular stroma. This is the first study to systematically describe the epithelial proliferations occurring in STUMP. This study suggests that, within STUMPs, there is epithelial-mesenchymal crosstalk, as has been described in benign prostate and in prostatic carcinogenesis. In unusual cases of STUMP, the epithelial proliferation may predominate to the extent that it can mask the diagnosis of STUMP. 相似文献
74.
Bini EJ Currie SL Shen H Bräu N Schmidt W Anand BS Cheung R Wright TL;VA HCV- Study Group 《Journal of clinical gastroenterology》2006,40(8):732-739
BACKGROUND: Although HIV testing is recommended for persons with hepatitis C virus (HCV) infection who are at risk for HIV, little is known about HIV testing in this population. METHODS: Data were prospectively collected in 4364 HCV-infected patients at 24 Veterans Affairs medical centers across the United States, including demographics, risk factors for HIV infection, and self-reported information on HIV testing. RESULTS: Overall, 76.8% had been tested for HIV at least once, 14.8% were never tested, 6.6% did not know if they were tested, and 1.8% declined to answer. Multivariable analysis identified injection drug use, needlestick injury, sex with a same-sex partner, a greater number of lifetime sexual partners, and sex with an injection drug user as factors that were independently associated with HIV testing. At least one risk factor for HIV infection was present in 84.5% of the 646 patients who were never HIV tested. Among the 3350 subjects who were tested for HIV, 8.4% were positive, 88.3% were negative, 2.4% did not know the results of their test, and 0.9% declined to answer. Multivariable analysis identified African American and Hispanic race/ethnicity, income < or = 10,000 dollars, sex with a same-sex partner, and sex with an injection drug user as the only variables that were independently associated with HIV seropositivity. CONCLUSIONS: Although a substantial proportion of HCV-infected patients have been tested for HIV, missed opportunities for early diagnosis of HIV infection exist. Public health strategies to improve HIV testing among patients with chronic HCV infection are needed. 相似文献
75.
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78.
Cardoso AA; Schultze JL; Boussiotis VA; Freeman GJ; Seamon MJ; Laszlo S; Billet A; Sallan SE; Gribben JG; Nadler LM 《Blood》1996,88(1):41-48
Even if neoplastic cells express tumor associated antigens they still may fail to function as antigen presenting cells (APC) if they lack expression of one or more molecules critical for the induction of productive immunity. These cellular defects can be repaired by physiologic activation, transfection, or fusion of tumor cells with professional APC. Although such defects can be repaired, antitumor specific T cells may still fail to respond in vivo if they may have been tolerized. Here, human pre-B cell acute lymphoblastic leukemia (pre-B ALL) was used as a model to determine if primary human tumor cells can function as alloantigen presenting cells (alloAPC) or alternatively whether they induce anergy. In the present report, we show that pre-B cell ALL express alloantigen and adhesion molecules but uniformly lack B7-1 (CD80) and only a subset express B7-2 (CD86). Pre-B ALL cells are inefficient or ineffective alloAPC and those cases that lack expression of B7-1 and B7-2 also induce alloantigen specific T- cell unresponsiveness. Under these circumstances, T-cell unresponsiveness could be prevented by physiologic activation of tumor cells via CD40, cross-linking CD28, or signaling through the common gamma chain of the interleukin-2 receptor on T cells. Taken together, these results suggest that pre-B ALL may be incapable of inducing clinically significant T-cell-mediated antileukemia responses. This defect may be not only due to their inability to function as APC, but also due to their potential to induce tolerance. Attempts to induce clinically significant antitumor immune responses may then require not only mechanisms to repair the antigen presenting capacity of the tumor cells, but also reversal of tolerance. 相似文献
79.
This article reports the first case of immune hemolytic anemia possibly associated with the ingestion of suprofen. The patient suffered from massive hemoglobinuria and acute renal failure. Serologic studies of the patient's serum revealed suprofen-dependent red cell antibodies. However, tolmetin-dependent antibodies were also found in the serum, showing the same properties as the suprofen antibodies and an even higher titer. The patient not only had drug-dependent antibodies in the serum, but also had developed autoantibodies, a phenomenon that has been described for several other drugs. The working mechanism by which suprofen and tolmetin caused immune hemolysis had properties of both the immune complex model and the induction of autoimmunity. Although it was unclear whether the immune hemolytic anemia was the result of suprofen, tolmetin, or cross-reacting antibodies, we feel that suprofen should be added to the list of nonsteroidal anti-inflammatory drugs associated with a positive direct antiglobulin test. 相似文献
80.
In a previously nephrectomized patient with a well functioning renal allograft, acute renal failure with massive polyuria and hypertension developed. Relief of a periureteric obstruction resulted in rapid correction of all three. Pathogenesis of hypotonic polyuria is thought to be a defect in the collecting duct permeability to water, simulating nephrogenic diabetes insipidus. Normal urinary dilution and acidification suggest intact function of the ascending loop of Henle and distal convoluted tubules. The quick reversal of polyuria and renal failure after obtaining relief of the obstruction suggest that both the decrease in the glomerular filtration rate and tubular dysfunctions are due to functional changes in the nephron rather than to organic damage, a possibility also borne out by the findings in a renal biopsy specimen showing normal glomeruli and intact tubular epithelial cells. Ureteric obstruction should be considered in any patient with renal failure and polyuria; it may be a correctable cause of hypertension. 相似文献