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21.
Chronic Ethanol Inhibits Inositol Metabolism in Specific Brain Regions   总被引:1,自引:0,他引:1  
Many neurotransmitters and hormones in the nervous system transmit signals through receptors coupled to the poly-phosphoinositide (PI) signaling pathway. In this study, an in vivo protocol with (3H]inositol was used to examine the effect of chronic ethanol administration on inositol metabolism and poly-PI turnover in the cerebral cortex, hippocampus, and cerebellum of mouse brain. C57BL/6 mice were given a nutritionally complete liquid diet containing either ethanol (5%, w/v) or isocaloric sucrose for 2 months. Mice were injected intracerebrally with rH]inositol; after 16 or 24 hr, they were injected intraperitoneally with lithium (8 mEq/kg body weight) to inhibit the inositol monophosphatase (IP1) activity. All mice were decapitated 4 hr after lithium injection. Labeled inositol phospholipids accounted for 16 to 23% of total labeled inositol in different regions of control mouse brain, and the percentages in the hippocampus were consistently higher than the cerebral cortex and cerebellum. In control mice, the percentages of labeled IP, after a 4-hr lithium treatment were 11.5%, 9.9%, and 3.7% for cerebral cortex, hippocampus, and cerebellum, respectively. Chronic ethanol feeding resulted in a significant (p < 0.05) decrease in the percent of labeled IP1 and inositol phospholipids, and this effect was observed in the cerebral cortex and, to a lesser extent, hippocampus but not cerebellum. When ratios of labeled IP1 were expressed against labeled inositol phospholipids as an index of the poly-PI turnover activity, significant decreases in IP/lipid ratios were observed in the cerebral cortex, but not the hippocampus or cerebellum. Although mice killed 24 + 4 hr after the last ethanol feeding would have experienced an 8-hr period of ethanol withdrawal, compared with the 16 + 4-hr group, no differences in IP/lipid ratios were observed between the two time groups. These results illustrate regional differences in the effect of chronic ethanol on inositol metabolism in the brain, but no difference in poly-PI turnover in brain due to ethanol withdrawal.  相似文献   
22.
There is a great need today for clinically useful instruments in the rehabilitation of chronic pain patients. The Arthritis Self-efficacy Scale measures patients' perceived self-efficacy to cope with the consequences of chronic arthritis. The aim of the present study was to evaluate a Swedish version of the Arthritis Self-efficacy Scale with respect to factor structure and reliability. Twenty-five chronic pain patients and twenty-four rheumatology patients were given a Swedish version of the Arthritis Self-efficacy Scale twice within a three week interval. The three factor structure of the scale was confirmed; Cronbach's alpha for internal consistency ranged between 0.82-0.91 and test-retest correlations ranged between 0.81-0.91, showing that the instrument satisfactorily met psychometric standards.  相似文献   
23.
. This is a report of unexplained anemia that persisted for 4 months in an adolescent renal transplant patient receiving immunosuppression that included prednisone, tacrolimus, and mycophenolate mofetil. This patient required monthly blood transfusions for fatigue, palpitations, and hematocrit levels between 15% and 17%. In addition, his posttransplant course was notable for the development of insulin-dependent diabetes mellitus. While receiving low-dose prednisone, he was switched from tacrolimus to cyclosporin and tapered off insulin injections over the next 2 months. At 4.5 months post-transplantation, further diagnostic evaluation was suggestive of parvovirus B19 infection as the cause for our patient’s chronic anemia. After testing negative for serum-specific parvovirus B19 IgM and IgG antibodies, parvovirus B19 infection was detected in blood by the polymerase chain reaction. Treatment with intravenous immunoglobulin (1 g/kg per day × 2 days) resulted in normalization of both his reticulocyte count and hematocrit within 6 weeks. At 4 months after receiving the immunoglobulin infusion, he has maintained a normal hematocrit level and stable renal function without requiring further blood transfusions. Received August 23, 1996; received in revised form and accepted November 20, 1996  相似文献   
24.
Abstract. The aim of the study was to determine the role of peripancreatic lymph node swelling in systemic immunological alterations during chronic hepatitis C (HC). The prospective study was carried out as a clinical study in a university hospital. Clinical, haematochemical and ultrasonographic findings in 182 patients were studied. Ultrasonography was performed by the same operator and the findings were evaluated blind without the operator knowing the clinical and haematochemical parameters. Hepatitis B virus (HBV) markers, anti-HCV antibodies. LKMl, cryoglobulinaemia, rheumatoid factor and anti-tissue antibodies were determined. Liver biopsy was carried out in 43 of the 182 patients. One or two pathological peripancreatic lymph nodes (PLNs) were present in 30 of the 182 patients and, of the 30, 28 were anti-HC positive. Only one patient in the non-PLN group was positive for anti-HCV, there being statistical significance ( P <0.0001) between the PLN and non-PLN groups. In HCV-positive patients, extrahepatic immunological manifestations were observed (cryoglobulinaemia; positivity to anti-smooth muscle, antinuclear and antimitochondrial antibodies; positivity to rheumatoid factor and LKMl). In five patients the presence of focal lymphocytic aggregates was detected by biopsy, whereas one patient presented typical ocular lesion of Mikulicz's syndrome. Our results may confirm the marked lymphotropism shown by the HC virus and indicate more complex immune system involvement, especially in view of the coexisting signs of immune system involvement related to the presence of intrahepatic cellular aggregates detected in our study. We believe that the peripancreatic adenopathy in chronic HCV hepatitis is an important diagnostic sign and may indicate an involvement of the C virus in the still unexplained extrahepatic immunological disorders.  相似文献   
25.
儿童慢性轻度哮喘治疗的临床研究   总被引:1,自引:0,他引:1  
岳孟源  肖洁  王薇 《上海医学》2004,27(7):500-501
目的 探讨 3~ 8岁儿童慢性轻度哮喘的早期干预治疗方法。方法 将 12 0例 3~ 8岁慢性轻度哮喘患儿随机均分为治疗组 1、2和对照组。治疗组 1:3~ 5岁患儿口服孟鲁司特 (顺尔宁 ) 4 .0mg/d ,5~ 8岁服5 .0mg/d ,疗程 3~ 6个月 ;治疗组 2 :予口服盐酸西替利嗪 2 .5~ 5 .0mg/d ,疗程 3~ 6个月 ;对照组 :口服安慰剂。均于每日睡前服用。结果 与治疗组 2及对照组相比 ,治疗组 1的日间及夜间症状出现率、急性加重发生率、月均 β 受体激动剂使用率、峰值呼气流速 (PEF)变化、嗜酸性粒细胞计数 (EC)下降率的差异有显著性 (P <0 .0 1) ,而住院率、药物不良反应率的差异无显著性 (P >0 .0 5 )。治疗组 2与对照组EC值的差异有显著性 (P <0 .0 1) ,其余指标的差异均无显著性 (P值均 >0 .0 5 )。结论 白三烯受体拮抗剂孟鲁司特单独用于慢性轻型哮喘儿童的早期干预治疗具有疗效好、不良反应小及患儿依从性高的特点  相似文献   
26.
27.
Little has been done to investigate the biochemical basis of chronic daily headache (CDH). Our group has recently demonstrated an increase in the cerebrospinal fluid (CSF) levels of nerve growth factor (NGF) in CDH patients, supporting the involvement of this growth factor in the abnormal processing of head pain in this pathological condition. Other members of the neurotrophin family, especially brain-derived neurotrophic factor (BDNF), have been hypothesized as being involved in the development of chronic head pain in patients affected by CDH, but so far no data are available on this subject. BDNF, NGF and glutamate levels were determined in the CSF of 25 patients affected by CDH with a previous history of migraine. These levels were compared with those of a group of 20 control subjects, for whom the CSF examination and other instrumental investigations excluded diseases of the central and peripheral nervous systems. Significantly higher levels of BDNF, NGF and glutamate were found in CDH patients compared with control subjects (p<0.0001, p<0.0002 and p<0.001, respectively). A significant positive correlation emerged between CSF values of BDNF and those of NGF (r=0.61, p<0.001) and glutamate (r=0.44, p<0.025) in CDH patients. No significant differences were detected in BDNF, NGF and glutamate levels between CDH patients with analgesic overuse and those without. These results support the involvement of BDNF in CDH through the potentiation of glutamatergic transmission involved in the processing of head pain. The significant correlation between BDNF and NGF levels suggests that NGF-mediated up-regulation of BDNF in central sites involved in long-term sensitization plays a key role in persistent head pain in CDH patients. Correspondence to P. Sarchielli  相似文献   
28.
29.
In order to define precisely the relation between descending monoaminergic systems and the motor system, we measured in the ventral horn of spinal cord of adult rats the variations of extracellular concentrations of 5-HT, 5-HIAA, DA and MHPG. Measurements were performed during rest, endurance running on a treadmill, and a post-exercise period, with microdialysis probes implanted permanently for 45 days. We found a slight decrease in both 5-HT and 5-HIAA during locomotion with a more marked decrease during the post-exercise period compared to the mean of rest values. In contrast, the concentration of DA and MHPG increased slightly during the exercise and decreased thereafter. These results, when compared with those of a previous study, which measured monoamines in the spinal cord white matter [C. Gerin, D. Bécquet, A. Privat, Direct evidence for the link between monoaminergic descending pathways and motor activity: I. A study with microdialysis probes implanted in the ventral funiculus of the spinal cord, Brain Res. 704 (1995) 191–201], highlight the complex regulation of the release of monoamines that occurs in the ventral horn.  相似文献   
30.
中度视网膜冲击伤后血视网膜屏障改变兔模型的评价   总被引:1,自引:0,他引:1  
应用BST-Ⅲ型生物激波管致伤建立的中度视网膜冲击伤兔模型,研究视网膜冲击伤后血视网膜屏障(BRB)的改变,结果显示,中度视网膜冲击后除有炎症性反应外,可致视网膜细胞部分变性和坏死,BRB轻度损害和视网膜电图(ERG)b波波幅下降40%。由于受损细胞在某些因素如自由基的作用下可进一步导致BRB严重继发性损害。如早期进行正确处理,可能阻止这种“不稳定”受损细胞的继发性损害。因此,该模型可用于研究视网  相似文献   
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