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991.
The influence of psychological stress and socioeconomic status on platelet activation in men 总被引:7,自引:0,他引:7
OBJECTIVE: Circulating monocyte- and neutrophil-platelet aggregates are sensitive markers of in vivo platelet activation. Socioeconomic status is inversely associated with risk of coronary heart disease. We assessed the impact of psychological stress on leukocyte-platelet aggregates in men from higher and lower socioeconomic status groups. METHODS: Participants were 37 healthy non-smoking men aged 30-59 years, divided by occupation into higher and lower social status groups. Blood was drawn at baseline, immediately following stressful behavioural tasks, and at 30 and 75 min post-stress, and aggregates were analysed using flow cytometry. Cardiovascular and subjective stress responses were also monitored. RESULTS: There were significant increases following stress in monocyte-, neutrophil-, lymphocyte- and total leukocyte-platelet aggregates (all P<0.05). The largest responses were in monocyte-platelet (21% increase) and neutrophil-platelet (16.7% increase) aggregates. Lower socioeconomic status men had greater numbers of leukocyte-platelet aggregates throughout, but the magnitude of stress responses did not vary with social status. The increase in monocyte- and leukocyte-platelet aggregates was associated with systolic blood pressure stress responsivity. CONCLUSIONS: Psychological stress induces platelet activation as indexed by leukocyte-platelet aggregates, and correlations with cardiovascular stress reactions suggest that sympathoadrenal responses may be responsible. Platelet activation may be a mechanism through which social position influences cardiovascular disease risk. 相似文献
992.
Baker CJ Rench MA Fernandez M Paoletti LC Kasper DL Edwards MS 《The Journal of infectious diseases》2003,188(1):66-73
To determine whether 2 monovalent group B streptococcus (GBS) serotype II or III capsular polysaccharide (CPS)-tetanus toxoid (TT) conjugate vaccines combined in a single intramuscular dose would elicit immune responses comparable to those of monovalent vaccines, 75 healthy adults were randomized to receive GBS II-TT (3.6 micro g of CPS), GBS III-TT (12.5 micro g of CPS), or a bivalent mixture of GBS II-TT/III-TT vaccine (double-masked design). Vaccines were well tolerated. Four-fold or greater increases in GBS II or III CPS-specific IgG, respectively, were noted in postimmunization serum samples from 80%-90% of bivalent conjugate vaccine recipients, and these responses were similar to those of recipients of GBS II-TT or GBS III-TT monovalent vaccines. Immune serum samples promoted the opsonophagocytic killing of types II and III GBS in vitro. Unexpectedly, some recipients of these vaccines developed cross-reactive antibodies to the structurally similar heterologous polysaccharide. These results support the feasibility of a multivalent vaccine for the 5 prevalent invasive disease-causing GBS CPS serotypes. 相似文献
993.
994.
Innovative educational strategies to prepare nurse executives for new leadership roles 总被引:2,自引:0,他引:2
Distance education has grown over the last decades. As technology has improved, so has our ability to provide students with education options. Excelsior College has taken advantage of this digital age to bring together global nurse leaders and given them the opportunity participate self-paced learning at home. Excelsior is a leader in online education and now has expanded by offering masters courses with a specialty in clinical systems management and health care informatics to nurses worldwide. 相似文献
995.
AIMS: To describe the laboratory confirmation of meningococcal disease, using culture and non-culture based techniques, between 1993 and 1999 as part of a national service in Scotland. METHODS: Samples from patients with suspected meningococcal disease in Scotland were analysed by culture and non-culture based techniques to gain a laboratory confirmation of disease. Data were analysed to establish the number of disease cases, the serogroups of the organisms involved, and the importance of the techniques used. RESULTS: Between 1993 and 1999, there was a total of 1749 notified cases of meningococcal disease in Scotland. Culture based methods provided a laboratory confirmation of 788 cases whereas non-culture techniques confirmed 461 cases. CONCLUSIONS: Non-culture techniques were a useful addition to culture based techniques in Scotland and improved the dataset required for public health management, disease surveillance, and vaccine policy. 相似文献
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999.
Prevalence of methicillin-resistant Staphylococcus aureus nasal carriage in the community pediatric population 总被引:1,自引:0,他引:1
Nakamura MM Rohling KL Shashaty M Lu H Tang YW Edwards KM 《The Pediatric infectious disease journal》2002,21(10):917-922
BACKGROUND: Reports from various geographic regions indicate that the prevalence of community-acquired methicillin-resistant (MRSA) infection is increasing. The primary reservoir is the anterior nares; nasal carriage is a risk factor for infection in a variety of populations. Little is known about MRSA nasal carriage rates among children in Nashville, TN and the associated likelihood of community MRSA transmission. METHODS: Nasal swabs were collected from 500 children at well-child visits at either a university hospital pediatric clinic or a private pediatric office. Cultures were plated onto selective staphylococcal media, with or without oxacillin. isolates were confirmed by coagulase tube testing. Antibiotic susceptibilities were determined for suspected methicillin-resistant isolates by standard broth microdilution methods (National Committee for Clinical Laboratory Standards). Pulsed field gel electrophoresis was used to evaluate epidemiologic relatedness. PCR testing was done to assess for the gene. A parent questionnaire was administered regarding MRSA risk factors. RESULTS: Four patients had oxacillin-resistant isolates (MIC >or= 4 microg/ml), and two had borderline resistant isolates (MICs = 1 and 2 microg/ml). One of the borderline-resistant isolates and one of the MRSA isolates had pulsed field gel electrophoresis typing results indicating close relatedness. The gene was present in all resistant isolates and one of the borderline-resistant isolates. Only having a household member employed in a hospital was associated with a greater risk of MRSA nasal carriage (odds ratio, 9.6; P= 0.008). CONCLUSIONS: MRSA nasal colonization is present within Nashville's healthy pediatric population. Children with household contacts employed in a hospital are significantly more likely to be colonized. 相似文献
1000.