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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   
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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   
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OBJECTIVE: To compare laser-assisted tympanostomy (LAT) with radiofrequency myringotomy (RFM), as well as the effectiveness of mitomycin C (MC) on the above techniques, in rabbits. STUDY DESIGN: Experimental animal research protocol. SETTING: University of Crete, School of Medicine, Medical Experimental Education and Research Center. METHODS: Bilateral myringotomies were performed under general anesthesia on 40 rabbits. LAT was performed on 20 animals (40 ears) and RFM on the remaining 20 animals (40 ears). MC (0.3 mg/mL) pledgets were applied to the right ears and saline pledgets to the left ears. Animals were monitored weekly using otomicroscopy until myringotomy closure. Kaplan-Meier survival techniques were used to compare myringotomy patency times. INTERVENTIONS: Under general anesthesia, bilateral LAT was performed on 20 rabbits and bilateral RFM on 20 rabbits. MAIN OUTCOME MEASURES: Myringotomy patency time. RESULTS: The mean patency times of the saline-treated ears were: 1.85 weeks (95% confidence interval [CI], 1.556-2.144 wk) for the LAT group and 1.70 weeks (95% CI, 1.494-1.906 wk) for the RFM group. This difference was not significant (p > 0.5). MC application significantly prolonged mean patency time (p < 0.0001) in both LAT and RFM groups. The mean patency times in the MC-treated ears were 5.45 weeks (95% CI, 5.226-5.674 wk) for the LAT group and 5.55 weeks (95% CI, 5.285-5.815 wk) for the RFM group. This difference was not significant (p > 0.5). CONCLUSION: There is no significant difference in myringotomy patency times between LAT and RFM techniques in rabbits, whereas MC significantly prolongs the patency rate of either technique.  相似文献   
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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   
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Objective

OSD-6 is a disease specific questionnaire for pediatric obstructive sleep apnea (OSA). The aims of this study were to validate OSD-6 in Greek language and correlate OSD-6 with polysomnography results.

Study design

Prospective study.

Setting

Tertiary referral center.

Subjects and methods

OSD-6 questionnaire was translated to Greek and back to English. A prospective study was conducted on children undergoing overnight polysomnography due to snoring and disrupted sleep. Test–retest evaluation was carried out. Internal consistency and test–retest reliability were evaluated. Validity was assessed by exploring correlations between OSD-6 scores and apnea–hypopnea index (AHI), and by comparing total scores of OSA and non-OSA groups. Responsiveness was assessed by comparing preoperative to postoperative total scores in OSA children who underwent adenotonsillectomy.

Results

Test–retest evaluation of 91 subjects showed good internal consistency (Cronbach’s alpha 0.860 for test and 0.873 for retest) and reliability (Pearson’s correlation coefficients between test and retest scores: 0.751–0.546; p < 0.01). Total and domains’ OSD-6 scores and AHI were significantly correlated (Spearman’s correlation coefficients: 0.277–0.630; p < 0.01), while children with OSA had higher total OSD-6 score than those without OSA (median (interquartile range): 16 (11) vs. 10 (7), respectively; p < 0.01), indicating good validity. Postoperative OSD-6 scores were significantly lower than preoperative (2.84 ± 3.21 vs. 15.42 ± 6.48, respectively; p < 0.001), suggesting good responsiveness.

Conclusion

The Greek version of the OSD-6 questionnaire proved to be a valid instrument with satisfactory internal consistency, reliability, validity and responsiveness. Furthermore, in our study OSD-6 was significantly correlated to polysomnography results.  相似文献   
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