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881.
Lower sedentary metabolic rate in women compared with men.   总被引:2,自引:0,他引:2       下载免费PDF全文
Since females have a greater prevalence of obesity compared with males, the question arises whether females have lower metabolic rate than males after adjusting for differences in body weight and composition. 24-h energy expenditure (24EE), basal metabolic rate (BMR), and sleeping metabolic rate (SMR) were measured in a respiratory chamber in 235 healthy, nondiabetic Caucasian subjects (114 males, 121 females). Body composition was determined by hydrodensitometry. 24EE was 124 +/- 38 kcal/d (P less than 0.002) higher in males than females after adjusting for differences in fat-free mass, fat mass, and age. Spontaneous physical activity was not significantly different between males and females. Since adjusted 24EE was 106 +/- 39 kcal/d (P less than 0.01) higher in females during the luteal phase of the menstrual cycle compared with females during the follicular phase, energy expenditure was analyzed in a subset (greater than 50 yr) to minimize the confounding effect of menstrual status. 24EE (160 +/- 66 kcal/d; P less than 0.03), BMR (116 +/- 45; P less than 0.02), and SMR (208 +/- 68 kcal/d; P less than 0.005) were higher in males compared with females of the older subset after adjusting for differences in body composition, age, and activity. In summary, sedentary 24EE is approximately 5-10% lower in females compared with males after adjusting for differences in body composition, age, and activity.  相似文献   
882.
The folate antagonist methotrexate (MTX) is extensively used in graft-versus-host disease, rheumatoid arthritis, and other chronic inflammatory disorders. In addition to its antiinflammatory activity associated with increased release of adenosine, MTX exerts antiproliferative properties by inhibition of dihydrofolate reductase and other folate-dependent enzymes. However, the mechanisms of immunosuppressive properties associated with low-dose MTX treatments are still elusive. We report here that MTX (0.1-10 microM) induces apoptosis of in vitro activated T cells from human peripheral blood. PBL exposed to MTX for 8 h, then activated in drug-free medium, underwent apoptosis, which was completely abrogated by addition of folinic acid or thymidine. Apoptosis of activated T cells did not require interaction between CD95 (Fas, APO-1) and its ligand, and adenosine release accounted for only a small part of this MTX activity. Apoptosis required progression of activated T cells to the S phase of the cell cycle, as it was prevented by drugs or antibodies that interfere with IL-2 synthesis or signaling pathways. MTX achieved clonal deletion of activated T cells in mixed lymphocyte reactions. Finally, in vitro activation of PBL taken from rheumatoid arthritis patients after MTX injection resulted in apoptosis. Altogether, the data demonstrate that MTX can selectively delete activated peripheral blood T cells by a CD95-independent pathway. This property could be used as a new pharmacological end point to optimize dosage and timing of MTX administration. It may account for the immunosuppressive effects of low-dose MTX treatments.  相似文献   
883.
Advances in neuroscience and biomedical engineering deeply affect the clinical practice of physical medicine & rehabilitation. New research findings and engineering tools are continuously made available that have the potential of dramatically enhancing the ability of clinicians to design effective rehabilitation interventions. This quickly evolving research field is difficult to track because related literature appears in a wide range of scientific journals. There is a need for a scientific journal that offers to its readership a forum at the intersection of neuroscience, biomedical engineering, and physical medicine & rehabilitation. The Journal of NeuroEngineering and Rehabilitation (JNER) is intended to fill this gap and foster cross-fertilizations among these disciplines. By making readily available to clinicians selected studies with potential impact on physical medicine & rehabilitation, JNER is anticipated to foster the development of novel and more effective rehabilitation strategies. Conversely, by presenting clinical problems to a readership of neuroscientists and engineers, JNER is expected to generate innovative work in neuroscience and biomedical engineering with future applications to physical medicine & rehabilitation. JNER will leverage on Open Access as a means to guarantee that its content is readily available to scientists, clinicians, and the general public thus promoting scientific and technological advances that are relevant to rehabilitation. JNER is an Open Access initiative. Open Access assures dissemination to the widest possible audience and is seen by many as essential for publicly funded research. BioMed Central offers an outstanding platform to make JNER possible and allow neuroscientists, biomedical engineers, and clinicians to see their work published in a timely manner and thus make an immediate impact in the field of rehabilitation. JNER will focus on innovative work with higher likelihood of a dramatic impact on rehabilitation. Thus, priority will be given to outstanding and visionary scientific reports, i.e. those proposing exceptionally innovative concepts with great potential in the field.  相似文献   
884.
Cancer of the biliary confluence also known as hilar cholangiocarcinoma (HC) or Klatskin tumor, is a rare type of neoplastic disease constituting approximately 40%-60% of intrahepatic malignancies, and 2% of all cancers. The prognosis is extremely poor and the majority of Klatskin tumors are deemed unresectable upon diagnosis. Most patients with unresectable bile duct cancer die within the first year after diagnosis, due to hepatic failure, and/or infectious complications secondary to biliary obstruction. Curative treatments include surgical resection and liver transplantation in highly selected patients. Nevertheless, very few patients are eligible for surgery or transplant at the time of diagnosis. For patients with unresectable HC, radiotherapy, chemotherapy, photodynamic therapy, and liver-directed minimally invasive procedures such as percutaneous image-guided ablation and intra-arterial chemoembolization are recommended treatment options. This review focuses on currently available treatment options for unresectable HC and discusses future perspectives that could optimize outcomes.  相似文献   
885.
Individuals scoring either High, Medium, or Low on the Homosexism Short-Form scale (Hansen, 1982) made speeded decisions to neutral (N), mildly provocative (MP), or very provocative (VP) statements regarding issues relating to homophobia. These three groups did not differ on age, education, reading rate, or vocabulary ability. It was predicted that individuals High in homophobia would produce faster reaction times to the VP sentences than those individuals scoring Medium or Low in homophobia. Results indicated the opposite pattern. Individuals scoring High in homophobia actually had slower reaction times to VP sentences than did either the Medium or Low homophobia individuals. Results are discussed within an inhibitory framework related to the High homophobia individuals' overall homophobia schema. © 1998 John Wiley & Sons, Inc. J Clin Psychol 54: 155–162, 1998.  相似文献   
886.
887.
Anti-inflammatory activity was detected in the CH(2)Cl(2) extract of the aerial parts of Eupatorium buniifolium using the TPA-mouse ear model. Three compounds isolated from this extract, by bioassay-guided fractionation, significantly inhibited the inflammatory response. The compounds were identified as 5,7,5'-trihydroxy-3,6,2',4'-tetramethoxyflavone (1), scopoletin (2) and centaureidin (3) which inhibited the edema by 67.3 %, 59.8 % and 49.7 %, respectively, at a dose of 1 mg/ear.  相似文献   
888.
Extracts of Argentine plant species used in folk medicine were evaluated for their antioxidant properties and ability to influence human neutrophil functions, including superoxide anion release and degranulation. The infusion and methanol extract of Achyrocline flaccida , and the infusion of Pterocaulon polystachium exhibited chain-breaking antioxidant activity in Fe2+/ascorbate-induced lipid peroxidation of rat liver microsomal fractions and scavenged peroxyl radicals in an aqueous assay system. Nevertheless their superoxide scavenging ability was lower. The dichloromethane extracts of Phyllanthus sellowianus, Achyrocline flaccida, Gamochaeta simplicicaulis, Pterocaulon polystachium and Eupatorium buniifolium , besides the infusion of Eupatorium buniifolium and the methanol extract of Pterocaulon polystachium , inhibited neutrophil functions.  相似文献   
889.
It is generally believed that the Palmaz-Schatz stent maintains a strong radial force, preventing stent recoil. However, the capacity to prevent recoil is largely governed by the hardness or resistance of the lesion. We report two cases of “acute Palmaz-Schatz stent recoil,” documented by intravascular ultrasound, and suggest a novel treatment of this unusual problem. © 1996 Wiley-Liss, Inc.  相似文献   
890.
We have analysed the expression of the HMGA2 gene in a panel of normal and neoplastic thyroid tissues by immunohistochemistry and quantitative RT-PCR. HMGA2 protein was detectable in four out of 21 follicular carcinomas, 30 out of 45 papillary carcinomas, and 11 out of 12 undifferentiated carcinomas. As far as follicular thyroid adenomas are concerned, only three cases of the 31 analysed showed HMGA2 protein expression, whereas it was absent in seven normal thyroid tissues and in 12 hyperplastic nodules. Quantitative RT-PCR showed that almost all the papillary thyroid carcinomas and 13 out of 16 follicular thyroid carcinomas express much higher HMGA2 specific mRNA levels in comparison to normal thyroids and adenomas. Therefore, our data support the quantitative RT-PCR analysis of HMGA2 expression, rather than immunohistochemistry, as a powerful tool for the diagnosis of thyroid neoplasias.  相似文献   
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