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991.
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993.
Subarachnoid hemorrhage is frequently associated with poor prognoses. Three different hemodynamic phases were identified during subarachnoid hemorrhage: oligemia, hyperemia, and vasospasm. Each phase is associated with brain metabolic changes. In this review, we correlated the hemodynamic phases with brain metabolism and potential treatment options in the hopes of improving patient prognoses.  相似文献   
994.
RNA interference (RNAi) is a biological process in which a double-stranded RNA directs the silencing of target genes in a sequence-specific manner. Exogenously delivered or endogenously encoded double-stranded RNAs can enter the RNAi pathway and guide the suppression of transgenes and cellular genes. This technique has emerged as a powerful tool for reverse genetic studies aimed toward the elucidation of gene function in numerous biological models. Two approaches, the use of small interfering RNAs and short hairpin RNAs (shRNAs), have been developed to permit the application of RNAi technology in mammalian cells. Here we describe the use of a shRNA-based live-cell microarray that allows simple, low-cost, high-throughput screening of phenotypes caused by the silencing of specific endogenous genes. This approach is a variation of "reverse transfection" in which mammalian cells are cultured on a microarray slide spotted with different shRNAs in a transfection carrier. Individual cell clusters become transfected with a defined shRNA that directs the inhibition of a particular gene of interest, potentially producing a specific phenotype. We have validated this approach by targeting genes involved in cytokinesis and proteasome-mediated proteolysis.  相似文献   
995.
Digestive symptoms in young individuals: survey among medical students]   总被引:1,自引:0,他引:1  
The purpose of this study was to assess the frequency patterns of 8 digestive symptoms and related features, with regard to functional disorders, in young adults. A sample of 279 subjects, representing the student body at the Medical School of Brasília, filled up the self-report questionnaire. From 20% to 27% of subjects reported more than 6 episodes of one more of the following symptoms, within a 12-month period: indigestion, distension, constipation, heartburn, abdominal pain, and diarrhea. A higher prevalence of constipation in women was a significant (p < 0.05) difference between the sexes. Dyspepsia and irritable bowel syndrome (IBS) were identified by clinical criteria in 25% and 9% of subjects, respectively, while 4% disclosed the occurrence of an organic disease. About 30% of the subjects volunteered perceptions on the meaning of the symptoms, while 22% reported days of restricted activities ascribed to the symptoms. Days of restricted activities were significantly (p < 0.05) related to the number, the type (diarrhea, nausea and vomiting, and abdominal pain), and the IBS pattern of symptoms (but not to the dyspepsia pattern). In conclusion, a substantial proportion of subjects in this student group, contacted at the workplace, showed indexes of clinical dysfunction (recurrence of multiple symptoms), and of social dysfunction (days of restricted activity), which indicate persistent limitations on the digestive health status.  相似文献   
996.
Despite the advent of more effective treatments for HIV-1 infection, cognitive impairment is still frequent and questions remain regarding which areas of impairment are more common in the different disease stages. This study investigated cognitive performance over an 8-year period of time in 59 HIV-1 seropositive (HIV-1+) men who were clinically asymptomatic at study entry, in comparison to a cohort of 55 HIV-1 seronegative (HIV-1-) men. Every 6 months we examined cognitive functioning in 5 domains-fine motor speed, attention, verbal memory, executive functioning, and speed of information processing. We found that patients with AIDS scored significantly worse on fine motor speed and speed of information processing than HIV-1- individuals and the HIV-1+ non-AIDS patients. In addition, the HIV-1+ non-AIDS patients performed more poorly than the HIV-1- group on speed of information processing. Depressive symptoms were also associated with diminished performance on measures of attention, executive functioning, and speed of information processing. Further research is needed to examine the effects of disease stage and depression on cognitive impairment in the era of new HIV treatments.  相似文献   
997.
Thirty-nine patients with acute cervical spine fractures and/or dislocations between C3 and C7 were submitted to an anterior approach using bone graft fixation without screw and plate systems and three required a preliminary posterior approach to reduce a dislocation. Graft dislodgement due to technical problems occurred at a rate of 7.7% postoperatively and 2.8% 1 month later. No redislodgement occurred. All fusions became solid after 3 months. Their progress was based on the Frankel scale, before surgery, at the moment of the discharge, and at 6 months follow-up. This experience shows how patients with an acute cervical injury can improve even when admitted late after trauma.  相似文献   
998.
In order to benefit from antiretroviral therapy, pregnant women infected with HIV must be tested and diagnosed. Not infrequently, however, women present in labor without prior prenatal care and are thus unable to benefit fully from HIV testing and, if infected, antiretroviral therapy. In this study we evaluated the need for rapid perinatal HIV testing for untested mothers presenting in labor in a public maternal–child hospital that provides care for metropolitan Porto Alegre, Brazil, and potentially modifiable risk factors for noncompliance with national recommendations. We surveyed a consecutive sample of women who gave birth at Hospital Materno–Infantil Presidente Vargas (Presidente Vargas Mother-and-child Hospital) in August–October 2001and administered a structured questionnaire to consenting participants. The questionnaire consisted of demographic data, information on health-seeking behavior, knowledge of HIV infection, and testing during pregnancy. We confirmed information on HIV testing, syphilis, and hepatitis B by examination of the patient's prenatal records. We also obtained data regarding laboratory testing and treatment during labor and delivery (e.g., HIV testing, antiretroviral treatment, and suppression of lactation) from hospital inpatient charts. Of 214 eligible participants, 209 (98%) agreed to participate in the study. Overall 173 (83%) of the 209 participants had had a previous HIV test and 36 (17%) had not. Women with fewer pregnancies were more likely to have been tested (p = .017), as were women with lower family incomes (p = .007). No women had received rapid tests in the delivery room. Of the 209 participants, 201 (96%) had had at least one prenatal visit and 169 (81%) had had three or more visits; 12 (6%) of these reported that they had not been offered an HIV test, 5 (2%) did not know if testing had been offered or not, and 191 (95%) reported that they had been offered a test. We were able to obtain prenatal records for 190 (95%) of the 201participants who had received prenatal care. HIV testing was not mentioned in 9% of charts. Results of syphilis tests were recorded on prenatal records or hospital charts for 167 (80%)participants, and results of hepatitis B surface antigen were found for 93 (45%). Women who to 30pchad had three or more prenatal visits were significantly more likely to have been tested for to 30pcHIV (OR 46.96, 95% CI, 15.92–144.85, .0001), syphilis (OR 31.64, 95% CI, 11.81–87.42, p < .0001) or HBsAg (OR, 4.88, 95% CI, 1.91–12.99, p < .0001) than women who had had two prenatal visits or fewer. Our study showed shown that in 12% of the pregnancies included in our sample national recommendations for prenatal or perinatal testing were not followed, and in an additional 5%, HIV testing, though offered, was not obtained. These women could potentially have benefited from rapid HIV testing. As knowledge of HIV and risk factors for transmission were almost universal in our sample, we believe that the passive health-seeking behavior we observed may offer an opportunity for targeting new efforts to promote the importance of prenatal care and prenatal diagnosis of HIV.  相似文献   
999.
Sweet's syndrome, or febrile neutrophilic dermatosis, is a process characterized by fever, red tender plaques, neutrophilia and neutrophilic dermal infiltrate with papilar edema in the absence of vasculitis. The association with intestinal inflammatory disease is inusual, a new case associated with ulcerative colitis is reported, and we perform a literature review of Sweet's associated intestinal inflammatory disease.  相似文献   
1000.
ATP diphosphohydrolase is an enzyme described in platelets and may be related to the control of ADP-dependent platelet aggregation. Platelet aggregation in atherosclerotic coronary arteries, and the release of platelet-derived factors, play an important role in coronary artery disease syndromes. In this study, we determined the activity of ATP diphosphohydrolase in platelets from patients with chronic and acute coronary artery disease syndromes and healthy persons. The following groups were studied: healthy persons (group I), patients with chronic heart disease (group II) and acute heart disease (group III). Results did not demonstrate differences between the groups studied. The control group demonstrated a lower range of enzyme activity. The patients from groups II and III had ingested drugs with actions upon the cardiovascular system and the effect, in vitro, of these drugs upon the ATP diphosphohydrolase activity in human platelets was also investigated. The in vitro experiments demonstrated that 2.0 mM acetylsalicylic acid inhibited ATP hydrolysis by human platelets by approximately 55%. Significant correlation was observed between ADP hydrolysis and glucose blood levels in the control group and between ATP hydrolysis and triglycerides in the group II. These results contribute to our understanding of a possible relationship between ATP diphosphohydrolase and thrombogenesis.  相似文献   
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