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81.
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.  相似文献   
82.
Pseudophakic cystoid macular oedema (PCMO) remains a significant cause of compromised postoperative vision in contemporary cataract surgery. Well‐established risk factors include intraoperative complications such as posterior capsule rupture and preoperative factors including: diabetes mellitus, uveitis, retinal vein occlusion, epiretinal membrane. The role of topical glaucoma medications in PCMO continues to be debated. Current treatment strategies largely target suppression of inflammation. Topical NSAIDs remain the mainstay in prophylaxis and treatment of PCMO. Topical corticosteroids are commonly used as monotherapy or in combination with NSAIDs. Unfortunately, high‐quality trials are notably lacking for other PCMO treatment modalities such as: periocular corticosteroids, orbital floor triamcinolone, intravitreal triamcinolone, corticosteroid implants, intravitreal bevacizumab and pars‐plana vitrectomy. A lack of consistency in defining PCMO and resolution of PCMO explains why even large systematic reviews may come to contradictory conclusions. This review explores the varied contemporary evidence‐base in relation to the aetiology, diagnosis, prophylaxis and treatment of PCMO.  相似文献   
83.
We assessed the risk of pneumonia due to Pneumocystis carinii in 1665 participants in the Multicenter AIDS Cohort Study who were seropositive for human immunodeficiency virus type 1 (HIV-1) but did not have the acquired immunodeficiency syndrome (AIDS) and were not receiving prophylaxis against P. carinii. During 48 months of follow-up, 168 participants (10.1 percent) had a first episode of P. carinii pneumonia. The risk was greatly increased in participants with CD4+ cell counts at base line of 200 per cubic millimeter or less (relative risk, 4.9; 95 percent confidence interval, 3.1 to 8.0). Although most participants (60.7 percent) described no HIV-1-related symptoms at the clinic visit at which a CD4+ cell count of 200 per cubic millimeter or less was first noted, this finding during follow-up was also associated with an increased risk of P. carinii pneumonia. The development of thrush or fever significantly and independently increased the risk of P. carinii pneumonia in these patients (adjusted relative risks, 1.86 and 2.15 for thrush and fever, respectively). Most participants with CD4+ cell counts above 200 per cubic millimeter who had P. carinii pneumonia within six months were symptomatic. We conclude that P. carinii pneumonia is unlikely to develop in HIV-1-infected patients unless their CD4+ cells are depleted to 200 per cubic millimeter or below or the patients are symptomatic, and therefore that prophylaxis should be reserved for such patients.  相似文献   
84.
The authors examined whether self-efficacy among African American abused women decreased their risk of suicide attempts through the mediating influences of perceived social support from friends, perceived social support from family, and perceived effectiveness for obtaining material resources. The sample consisted of 100 women who presented to a hospital following a suicide attempt and 100 women who presented to the same hospital for nonemergency medical problems. Results revealed that the association between self-efficacy and suicide attempt status was partially accounted for by the mediating roles of perceived social support from friends and family, and perceived effectiveness at obtaining resources. Findings suggest that interventions to increase abused women's self-efficacy should focus on increasing their capacity to obtain social and material resources.  相似文献   
85.
Earlier associations of polymorphism in classic HLA class II (DRB1 and DQB1) genes have been extended to include the accessory genes DMA and DMB as determinants of disseminated Mycobacterium avium complex (DMAC) infection among HIV-1-seropositive whites. From the Multicenter AIDS Cohort study, 176 DMAC cases were matched with 176 controls in a nested case-control study. PCR-based HLA genotyping techniques were used to resolve variants of DRB1 and DQB1 to their four-digit or five-digit alleles, and single-strand conformation polymorphism was used to resolve sequences in exon 3 at each DM locus. The DMA*0102 allele occurred less frequently among DMAC cases than among controls (OR = 0.46, p =.02). Combinations of DRB1 alleles with or without specific DMA and DMB variants showed significant differences in distributions between the cases and controls, but both of the previously associated class II alleles (DRB1*1501 and DRB1*0701) showed stronger positive associations with DMAC in the absence than in the presence of DMA*0102. Apparent joint effects of DRB1 and DM allelic combinations on occurrence and timing of DMAC suggest that class II disease relationships may be better predicted by biologically plausible interactive combinations than by polymorphisms in individual genes.  相似文献   
86.
Using a newly devised 50-channel photometer which records the opacity of growing bacterial cultures, it was shown that the time taken by cultures diluted 1/1000 in fresh broth to reach 50% of the opacity of a fully grown culture was inversely related to the concentration of organisms in the original culture. This relation was used to determine the numbers of survivors after exposure to benzylpenicillin and gentamicin alone and in combination. The procedure is commended as a labour-saving and potentially rapid method of obtaining comprehensive information on the bactericidal action and interaction of antibiotics.  相似文献   
87.
In a cohort of 1835 homosexual men who were seropositive for human immunodeficiency virus (HIV) on entry into a prospective study, the acquired immunodeficiency syndrome (AIDS) developed in 59 during a median follow-up of 15 months. We matched 5 seropositive controls to each case according to study center and date of enrollment and performed a case-control analysis to determine factors predictive of AIDS. In a multivariate analysis, a decreased number of T helper lymphocytes, an increased number of T suppressor lymphocytes, a low level of antibody to HIV, a high titer of cytomegalovirus antibody, and a history of sex with someone in whom AIDS developed were independently associated with subsequent AIDS. Separate analyses of risk factors for Kaposi's sarcoma and opportunistic infections failed to support previously reported associations between the use of nitrites or an elevated cytomegalovirus-antibody titer and Kaposi's sarcoma. These variables may be markers rather than determinants of disease progression. A vigorous antibody response to HIV infection may confer at least temporary protection against the progression of immunodeficiency to AIDS, or a low level of antibody to HIV may reflect a later stage of infection. The increased risk associated with a history of sex with someone in whom AIDS developed may indicate earlier infection in cases or infection with a more virulent strain of HIV. These results may be useful in counseling HIV-seropositive persons and in designing studies of clinical interventions.  相似文献   
88.
A homozygous 32-bp deletion in the gene encoding CCR5, a major coreceptor for HIV-1, leads to resistance to infection with HIV-1, and heterozygosity for the deletion is associated with delayed disease progression in persons infected with HIV-1. We investigated the effect of CCR5 heterozygosity on disease progression as measured by both CD4+ T-cell count decline and the occurrence of clinical AIDS symptoms. Using a unified statistical model for CD4 count progression and AIDS development, we examined whether the effect of CCR5 heterozygosity on clinical AIDS is direct or indirect through its effect on CD4 counts. Based on data from the Multicenter AIDS Cohort Study, we noted a protective effect of CCR5 heterozygosity on both CD4 cell count progression and on AIDS occurrence. Furthermore, we found that this protective effect on the occurrence of AIDS was completely mediated through an effect on the CD4 marker. Additional adjustment for the effect of an initial viral load measurement indicate that CCR5 heterozygosity did not have predictive value for either CD4 progression or the development of AIDS beyond its association with early viral load.  相似文献   
89.
The immunogenicity and protective efficacy of four versions of recombinant C-terminal 19-kDa epidermal growth factor-like region of the major surface protein 1 (rMSP1(19)) of Plasmodium falciparum was studied in Aotus monkeys. Vaccination with each of the four rMSP1(19) constructs elicited high levels of antibodies to MSP1(19) but only one construct, the 19-kDa fragment expressed as a secreted fusion protein from Saccharomyces cerevisiae (yP30P2MSP1(19)), induced a high degree of protective immunity in Aotus nancymai against lethal P. falciparum challenge. Protective formulation required Freund's adjuvant; vaccination with yP30P2MSP1(19) in six other adjuvants that are suitable for human use induced lower levels of antibody response and no protection. These results emphasize the need to continue the search for an adjuvant that is comparable to Freund's adjuvant in potency and is safe for use in humans.  相似文献   
90.
BACKGROUND. We performed a multicenter study in 1989 to determine whether screening whole-blood donors for human immunodeficiency virus type 1 (HIV-1) p24 antigen would improve transfusion safety by identifying carriers of the virus who are seronegative for HIV-1 antibody. METHODS. More than 500,000 donations were tested at 13 U.S. blood centers with test kits from two manufacturers. Units found repeatedly reactive were retested in a central laboratory; if the results were positive, they were confirmed by a neutralization assay. A subgroup of units was also tested for HIV-1 by the polymerase chain reaction. Selected donors confirmed or not confirmed as having p24 antigen were contacted for follow-up interviews to identify risk factors and undergo retesting for HIV-1 markers. RESULTS. Positive tests for p24 antigen were confirmed by neutralization in five donors (0.001 percent of all donations tested), all of whom were also positive for HIV-1 antibody and HIV-1 by polymerase chain reaction. Three of the antigen-positive donors had other markers of infectious disease that would have resulted in the exclusion of their blood; two had risk factors for HIV-1 that should have led to self-exclusion. Of 220 blood units with repeatedly reactive p24 antigen whose presence could not be confirmed by neutralization (0.04 percent of the donations studied), none were positive for HIV-1 antibody, HIV-1 by polymerase chain reaction (120 units tested), or virus culture (76 units tested)--attesting to the specificity of confirmatory neutralization. CONCLUSIONS. The finding that no donation studied was positive for p24 antigen and negative for HIV-1 antibody suggests that screening donors for p24 antigen with tests of the current level of sensitivity would not add substantially to the safety of the U.S. blood supply.  相似文献   
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