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Four experiments were conducted to investigate the effects of unavoidable shock, conflict conditions, taste, and food deprivation on the voluntary consumption of alcohol by rats. Experiment 1 showed that when rats were given unavoidable shocks for one hour every day, those living in their home cages consumed greater amounts of a 5% ethanol solution than did rats living in the shock chambers. Experiment 2 revealed that this increased alcohol consumption was maintained and further elevated when these same rats were subjected to conflict, and it did not decrease when the conflict conditions were terminated. When the unavoidable shock conditions were repeated in Experiment 3 with naive rats and the fluid choice consisted of a plain sucrose solution and one containing alcohol, rats in both the shock box and safety cage living conditions consumed very little of the sucrose-plus-alcohol solution. Rats living in the aversive environment even decreased consumption of the plain sucrose solution. Experiment 4 showed that simple food deprivation can also result in an increased intake of an alcohol solution. The tension reduction hypothesis cannot account for these results: they demonstrate that deprivation can influence alcohol consumption, and indicate that an aversive environment can interfere with drinking of any solution. The results also demonstrate both the positive and negative properties that alcohol can have.  相似文献   
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In X‐linked hypophosphatemia (XLH) and in its murine homologue, the Hyp mouse, increased circulating concentrations of fibroblast growth factor 23 (FGF‐23) are critical to the pathogenesis of disordered metabolism of phosphate (Pi) and 1,25‐dihydroxyvitamin D [1,25(OH)2D]. In this study, we hypothesized that in Hyp mice, FGF‐23‐mediated suppression of renal 1,25(OH)2D production and Pi reabsorption depends on activation of mitogen‐activated protein kinase (MAPK) signaling. Wild‐type and Hyp mice were administered either vehicle or the MEK inhibitor PD0325901 (12.5 mg/kg) orally daily for 4 days. At baseline, the renal abundance of early growth response 1 (egr1) mRNA was approximately 2‐fold greater in Hyp mice than in wild‐type mice. Treatment with PD0325901 greatly suppressed egr1 mRNA abundance in both wild‐type and Hyp mice. In Hyp mice, PD0325901 induced an 8‐fold increase in renal 1α‐hydroxylase mRNA expression and a 4‐fold increase in serum 1,25(OH)2D concentrations compared with vehicle‐treated Hyp mice. Serum Pi levels in Hyp mice increased significantly after treatment with PD0325901, and the increase was associated with increased renal Npt2a mRNA abundance and brush‐border membrane Npt2a protein expression. These findings provide evidence that in Hyp mice, MAPK signaling is constitutively activated in the kidney and support the hypothesis that the FGF‐23‐mediated suppression of renal 1,25(OH)2D production and Pi reabsorption depends on activation of MAPK signaling via MEK/ERK1/2. These findings demonstrate the physiologic importance of MAPK signaling in the actions of FGF‐23 in regulating renal 1,25(OH)2D and Pi metabolism. © 2011 American Society for Bone and Mineral Research  相似文献   
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Since 1992, the American Society of Anesthesiologists has produced 12 evidence-based practice guidelines, 2 practice advisories, and 3 guideline updates. These documents have assisted anesthesiologists and practitioners in many other specialties. Their brevity, practicality, and ease of use, coupled with a thorough and systematic evaluation of the evidence have been instrumental in bringing together the science and practice of medicine. The application of formal evidence-collection processes for literature and opinion and efficient analytic evaluations combine with the experience and practical knowledge of clinicians to produce widespread application of the guidelines.The evidence-based process developed by the ASA has been found to be adaptable to a wide variety of issues relating to clinical practice. The goal is to systematically collect and evaluate evidence from multiple sources and apply it ina comprehensive manner to the guideline recommendations. The ASA guideline and advisory development process is continuing to evolve in response to changes in medical technology, research, and practice. By providing synthesized evidence from multiple sources and robust clinical recommendations the ASA offers the practice of anesthesiology, an invaluable bridge between science and clinical practice.  相似文献   
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OBJECTIVE: Ionized field ablation, or coblation-assisted subtotal tonsillectomy, has been described as a new alternative technique for the management of tonsillar disease. This study was designed to review the incidence of complications in patients undergoing this procedure. STUDY DESIGN: A 10-surgeon retrospective chart review of the intraoperative and postoperative complications of patients undergoing ionized field ablation subtotal removal of tonsils was performed. Postoperative pain, dietary restrictions, and activity level were not reviewed. RESULTS: Of the 528 patients who underwent ionized field ablation of their tonsils, the incidence of intraoperative and postoperative complications compared favorably with those reported in retrospective studies in the literature for traditional subcapsular tonsillectomy. Significant postoperative bleeding occurred in less than 1%, and only 1 patient required surgical control of bleeding in the operating room. No patients required transfusions of any blood products. CONCLUSIONS: Ionized field ablation subtotal tonsillectomy may offer an alternative to traditional subcapsular tonsillar surgery with a decreased incidence of postoperative complications. Further study is necessary to establish the complication rate of this technique.  相似文献   
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The goals of the present study were to assess if there is an association between preoperative cardiac evaluation and surgery timing in patients with a hip fracture, to evaluate the relationship between surgery timing and postoperative morbidity and mortality, and to determine if the proper patients are being selected for noninvasive cardiac testing based on the practice guidelines published by the American College of Cardiology/American Heart Association Task Force. Surgery delay secondary to cardiac clearance may be a risk factor for increased postoperative complications that is independent of a patient's general medical condition. Surgical treatment of acute hip fractures may be delayed by many factors besides preoperative cardiac clearance, but it is the job of the orthopedic surgeon, who best understands the importance of timely surgery for a hip fracture, to minimize delays. Careful screening of patients who have sustained a hip fracture can improve overall outcomes by minimizing the number of patients whose surgical treatment is unnecessarily delayed for cardiac clearance.  相似文献   
29.
从假细锥香茶菜(Rabdosia coetsoides C.Y.Wu)叶分离得到新二萜成分,根据紫外光谱、红外光谱、质谱、核磁共振氢谱及碳谱等分析,推定了化学结构,并经X-射线衍射确证,命名为假细锥甲素。  相似文献   
30.
Proteoglycans and their component glycosaminoglycans are involved in such cell-cell and cell-matrix interactions as cell adhesion and migration, processes that are essential for embryonic and fetal development. As definitive organs such as skin emerge, structurally different proteoglycans partition into highly defined compartments. In skin, these compartments correspond to morphologically and functionally distinct layers. However, during the normal aging process, the relative amounts of structurally distinct proteoglycans apparently varies independently in each of these layers. This was demonstrated, in an indirect immunocytochemical study, through the use of monoclonal antibodies that detect structurally distinct domains in glycosaminoglycan chains of proteoglycans. Using samples of normal human skin obtained from individuals ranging in age from 20 weeks of gestation to 98 years of age, we determined that a common distribution pattern existed in skin. The epidermis contained chondroitin 4- and keratan sulfates, the basal lamina was the only layer that contained chondroitin 6-sulfate, the papillary and reticular dermis contained principally dermatan sulfate. In addition, antibodies that recognize native domains in chondroitin sulfates identified proteoglycan subsets that partitioned into distinct layers. An important new finding was that the relative amounts of specific types of glycosaminoglycans varied in an age- and layer-dependent manner. In the epidermis there was a notable increase in keratan sulfate beginning at age 50. Chondroitin 6-sulfate, found principally in the basal lamina, decreased after age 60. In the papillary dermis, the amount of dermatan sulfate increased after age 50, whereas the amount of novel chondroitin sulfate epitope, detected by antibody 4C3, decreased with age. Thus, age-related changes in proteoglycan distribution exist and correlate with morphologic and functional changes that occur in the intrinsic process of aging in human skin.  相似文献   
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