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41.
Conclusions and summary 245 patients (29 postgastrectomy and 216 with intact stomachs) were examined with the gastroduodenal fiberscope within 14 days of bleeding, 91 of these within 24 hr. Direct visualization of lesions was possible in 50%, and in a further 40% the diagnosis could be made by inference or exclusion. Only 4 wrong diagnoses were made. Sites of bleeding were roughly 60% duodenal, 40% stomach; acute erosions accounted for 33% of the total.This procedure, which is safe and well tolerated by the patient is easily learned and should if possible be performed in every patient with acute upper gastrointestinal hemorrhage. In the first 24 hr. it may be an important guide to therapy or aid to surgery.This study was supported by Grants AM 4978 and 2A-5286 from the U. S. Public Health Service, National Institutes of Arthritis and Metabolic Diseases.We acknowledge the assistance of the following Fellows and Residents who examined many of the patients reported in this study: Drs. Jerome G. Ippolito, C. Birnie Johnson, T. A. Farmer, P. W. Morris, J. B. Douglas, Ali M. Fahkro, B. S. Tynes, S. R. Furst, G. E. Ennis, J. W. Trigg Jr., Robert Ryan, Emmett T. Brunson, John Henderson, Omer Baker, B. P. Edmunds, E. Jack Green, and George G. B. Bilsten.  相似文献   
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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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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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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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Incidence of red cell antibodies after multiple blood transfusion   总被引:3,自引:0,他引:3  
A retrospective study was performed to estimate the frequency of alloimmunization against red cell (RBC) antigens in a multiply transfused group. Patients (n = 186) were studied who had received at least six blood transfusions during a period of at least 3 months. Some 6944 units of blood were transfused. One hundred forty patients had hematologic disorders. The patients' sera were investigated every 3 months with indirect antiglobulin tests and enzyme-treated RBCs. Twenty-two patients (11.8%) made 33 antibodies. Seven patients made more than one antibody. Eight of the 22 patients (36.4%) made their first antibody before or at the 10th transfusion. The risk of immunization increased with the number of transfusions. Influence of gender and age was not demonstrable. Nor was a relationship demonstrated between blood transfusion reactions and RBC antibody formation; no delayed hemolytic transfusion reactions occurred. Anti-E was demonstrated in 12 patients and anti-K in 15. When the gene frequencies were taken into account, it appeared that anti-E was made by 11.5 percent of E-negative patients, most of whom were immunized after an estimated three transfusions with E-positive blood. Anti-K was made by 8.7 percent of the K-negative patients, after an estimated 2.1 units of K-positive blood. It might be desirable to match red cell units for the E and K antigens in patients at relatively high risk. These are primarily patients who have already formed an antibody and are going to receive many transfusions and women of childbearing age who are to receive more than 4 units of blood.  相似文献   
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OBJECTIVE: Although disulfiram and naltrexone have been approved by the Food and Drug Administration for the treatment of alcoholism, no medications have been approved for individuals with alcohol dependence and comorbid psychiatric disorders. In particular, the effect of these medications on alcohol use outcomes and on specific psychiatric symptoms is still unknown in patients with the most common co-occurring disorder, major depression. METHOD: Two hundred fifty-four patients with a major Axis I psychiatric disorder and comorbid alcohol dependence were treated for 12 weeks in an outpatient medication study conducted at 3 Veterans Administration outpatient clinics. Randomization included (1) open randomization to disulfiram or no disulfiram, and (2) double-blind randomization to naltrexone or placebo. This resulted in 4 groups: (1) naltrexone alone, (2) placebo alone, (3) disulfiram and naltrexone, and (4) disulfiram and placebo. Primary outcomes were measures of alcohol use. Secondary outcomes included psychiatric symptoms assessed by the Hamilton Depression Rating Scale, alcohol craving, gamma-glutamyltransferase levels, and adverse events. RESULTS: One hundred thirty-nine subjects (54.7%) met the current Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria for major depression. There was no relationship between the diagnosis of depression and medication treatment on alcohol use outcomes, psychiatric symptoms, or the reporting of side effects for these medications. There was a significant interaction between diagnosis, medication group, and craving, where subjects with depression on disulfram reported lower craving over time than subjects with depression on naltrexone. CONCLUSIONS: The results suggest that disulfiram and naltrexone are safe pharmacotherapeutic agents for dually diagnosed individuals with depression for the treatment of alcohol use disorders.  相似文献   
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