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991.
Beutner EH Pelton S Hashimoto T Xu Y Plunkett RW Korman NJ Helm TN Jablonska S 《Journal of the American Academy of Dermatology》2002,47(6):841-851
We studied 3 recent cases of paraneoplastic pemphigus (PNP) in detail. Two patients died despite concerted management efforts. One patient received no treatment after the appearance of PNP and recovered completely from both PNP and lymphoma. Multiple serum studies of these 3 patients plus 9 other proven PNP cases revealed that 8 of 9 fatal PNP cases (referred to here as "group A") had distinctive cell surface antibodies detected by complement indirect immunofluorescent (CIIF) tests on monkey esophagus sections. By contrast, none of the sera from 3 patients with PNP who experienced long-term survival (referred to here as "group B") and none of 20 pemphigus vulgaris or 10 pemphigus foliaceus control sera revealed similar beaded cell surface CIIF reaction patterns, a difference that is statistically significant (P <.0001). Cell surface CIIF reaction patterns of group A PNP antibodies resemble the pattern of pemphigus antibody reactions in indirect immunofluorescent tests on the same substrate; however, the latter tend to be thinner and more linear, whereas the cell surface CIIF pattern tends to be more beaded, suggesting possible desmosomal reactions. We believe this test is useful in identifying an aggressive group A form of PNP. 相似文献
992.
The two major concerns in drug safety are adverse drug reactions and drug interactions. When multiple drug therapies are prescribed, drug interactions become an important consideration for patients and physicians. The life of a drug is reviewed with emphasis on absorption, distribution, metabolism, and excretion. Pharmacokinetic and pharmacodynamic mechanisms for drug interactions are reviewed. The contributions of P-glycoprotein, pharmacogenetic variation, and genetic polymorphisms to drug interactions are highlighted. Prediction of drug interactions is possible with knowledge of which agents are likely to cause alterations in drug metabolism. (J Am Acad Dermatol 2002;47:467-84.) Learning objective: At the conclusion of this learning activity, participants should have an understanding of the life of a drug. This knowledge should help predict important potential drug interactions. 相似文献
993.
What Syndrome Is This? 总被引:2,自引:0,他引:2
994.
Strakowski SM DelBello MP Zimmerman ME Getz GE Mills NP Ret J Shear P Adler CM 《The American journal of psychiatry》2002,159(11):1841-1847
OBJECTIVE: Ventriculomegaly has been reported in bipolar disorder, although whether it occurs at illness onset or progresses during the course of the disorder is unknown. In addition, it is unknown whether ventriculomegaly in bipolar disorder reflects acquired volume loss or underdevelopment of periventricular structures. METHOD: Magnetic resonance imaging was used to measure the volumes of the lateral and third ventricles and periventricular structures (caudate, putamen, thalamus, hippocampus). Patients with DSM-IV bipolar disorder, 18 who were having a first episode and 17 with multiple episodes, were compared with 32 healthy subjects. RESULTS: The lateral ventricles were significantly larger in the patients with multiple-episode bipolar disorder than in the first-episode patients or the healthy subjects, even after periventricular and total cerebral volumes were taken into account. Having larger lateral ventricles was associated with a higher number of prior manic episodes. The multiple-episode patients had a smaller total cerebral volume than the healthy subjects but not the first-episode patients. The putamen was significantly larger in the first-episode patients (and nearly so in the multiple-episode patients) than in the healthy subjects, although there was no difference between patient groups. CONCLUSIONS: Lateral ventriculomegaly was greater in bipolar disorder patients who had had repeated manic episodes, but it does not appear to be secondary to small critical periventricular structures. A larger than normal striatum, which has been reported in previous studies, was observed in first-episode patients. These results support the importance of prospectively studying neuroanatomic changes in bipolar disorder. 相似文献
995.
Trotter RT Cobb NS Whitham TG 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(15):10197-10202
To understand climate change, dendrochronologists have used tree ring analyses to reconstruct past climates, as well as ecological processes such as herbivore population dynamics. Such reconstructions, however, have been hindered by a lack of experiments that separate the influences of confounding impacts on tree rings, such as herbivores and the interactions of multiple factors. Our long-term experiments with scale insects on resistant and susceptible pines demonstrate three major points that are important to the application of this commonly used tool. (i) Herbivory reduced tree ring growth by 25-35%. (ii) The impact on ring growth distorted climate reconstruction, resulting in the overestimation of past moisture levels by more than 2-fold. Our data suggest that, if distortion because of herbivory has been a problem in previous reconstructions, estimates of the magnitude of recent climate changes are likely to be conservative. (iii) Our studies support a detectible plant resistance x herbivore x climate interaction in the tree ring record. Because resistance and susceptibility to herbivory are known to be genetically based in many systems, the potential exists to incorporate plant genetics into the field of dendrochronology, where it may be used to screen distortions from the tree ring record. 相似文献
996.
997.
The impact of regular ecstasy use on memory function 总被引:1,自引:0,他引:1
Aim To assess memory impairment in a group of regular users of ecstasy compared with a group of regular users of cannabis, after accounting for possible confounding factors such as other drug use, premorbid intelligence and psychopathology.
METHOD Comparative and regression analysis was used to determine the presence or absence of a difference in memory function between 40 regular ecstasy users and 37 regular users of cannabis, who were interviewed at the National Drug and Alcohol Research Centre in Sydney, Australia. Regression analysis was used to find associations between life-time exposure to ecstasy use and memory performance. Memory function was assessed using an age-standardized memory test. Other scales were used to assess premorbid intelligence, physical and psychological health, drug withdrawal and other drug use.
Results Initial comparative analysis showed a trend towards a significantly poorer performance by the regular ecstasy-using group on the 'auditory immediate memory' and 'auditory delayed memory' indices. When regression analysis was performed an estimate of verbal intelligence was found to be the most predictive of most memory indices including 'auditory immediate memory' and 'auditory delayed memory'. Life-time exposure to ecstasy was not predictive of the memory indices. The current frequency of cannabis use was found to have some predictive effect for immediate and delayed visual memory.
Conclusion This study does not show memory impairment in a group of ecstasy users relative to cannabis using controls. The previously reported association of life-time exposure to ecstasy and memory was not found. The findings may indicate a confounding role of cannabis use, as has been recently reported. 相似文献
METHOD Comparative and regression analysis was used to determine the presence or absence of a difference in memory function between 40 regular ecstasy users and 37 regular users of cannabis, who were interviewed at the National Drug and Alcohol Research Centre in Sydney, Australia. Regression analysis was used to find associations between life-time exposure to ecstasy use and memory performance. Memory function was assessed using an age-standardized memory test. Other scales were used to assess premorbid intelligence, physical and psychological health, drug withdrawal and other drug use.
Results Initial comparative analysis showed a trend towards a significantly poorer performance by the regular ecstasy-using group on the 'auditory immediate memory' and 'auditory delayed memory' indices. When regression analysis was performed an estimate of verbal intelligence was found to be the most predictive of most memory indices including 'auditory immediate memory' and 'auditory delayed memory'. Life-time exposure to ecstasy was not predictive of the memory indices. The current frequency of cannabis use was found to have some predictive effect for immediate and delayed visual memory.
Conclusion This study does not show memory impairment in a group of ecstasy users relative to cannabis using controls. The previously reported association of life-time exposure to ecstasy and memory was not found. The findings may indicate a confounding role of cannabis use, as has been recently reported. 相似文献
998.
999.
Engleman HM McDonald JP Graham D Lello GE Kingshott RN Coleman EL Mackay TW Douglas NJ 《American journal of respiratory and critical care medicine》2002,166(6):855-859
Mandibular repositioning splints (MRSs) and continuous positive airway pressure (CPAP) are used to treat the sleep apnea/hypopnea syndrome (SAHS). There are some data suggesting that patients with milder symptoms prefer MRS, but there are few comparative data on outcomes. Therefore, we performed a randomized crossover trial of 8 weeks of CPAP and 8 weeks of MRS treatment in consecutive new outpatients diagnosed with SAHS (apnea/hypopnea index [AHI] >or= 5/hour, and >or= 2 symptoms including sleepiness). Assessments at the end of both limbs comprised home sleep study, subjective ratings of treatment value, sleepiness, symptoms, and well-being, and objective tests of sleepiness and cognition. Forty-eight of 51 recruited patients completed the trial (12 women; age [mean +/- SD], 46 +/- 9 years; Epworth 14 +/- 4; median AHI, 22/hour; interquartile ratio [IQR], 11-43/hour). Significant (p 相似文献
1000.