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981.
Detection of mass lesions with MR colonography: preliminary report   总被引:13,自引:1,他引:12  
  相似文献   
982.
以Rev依赖性凋亡增强HIV-1gp160的抗原性   总被引:1,自引:0,他引:1  
目的 检测Rev(HIV的调控基因 )依赖性肿瘤坏死因子受体 (TNFR 1)和gp16 0双重表达质粒pDM12 8 TNFR 1(pT12 8)的凋亡诱导功能。方法 采用基因枪转导及流式细胞仪检测新质粒的表达功能。结果 新结构具有特异的选择性表达作用。当Rev存在时 ,能间接表达TNFR 1,明显诱导HeLa细胞凋亡 ,使绿荧光细胞百分率非常显著地低于阴性对照 (P <0 .0 1)。等质量转染时 ,TNFR 1表达量少于Hup6 0TNFR 1的pDC30 2 (pT6 0 ) ,故间接表达不及单纯pT6 0的直接表达 ,绿荧光细胞百分率显著高于pT6 0转染组 (P <0 .0 1)。培养 40h ,才有明显杀伤功能并接近单纯pT6 0 ,差异无显著性 (P>0 .0 1)。单纯pT12 8不能直接表达TNFR 1,绿荧光细胞百分率非常显著地高于单纯pT6 0转染组 (P<0 .0 1) ,接近阴性对照 ,培养 40h时差异无显著性 (P >0 .0 1)。当AD8或pMD +pRnv存在并表达Rev时 ,pT12 8均能表达TNFR 1,杀伤HeLa细胞 ,绿荧光细胞百分率非常显著地低于阴性对照 (P <0 .0 1)。pT12 8与pRev或AD8转染人正常的角质生成细胞时 ,能表达TNFR 1,诱导细胞凋亡。培养 72h后 ,阴性对照和单纯pT12 8组的绿荧光角质生成细胞数皆显著地超过pT12 8+pRev和pT12 8+pAD8组 (P <0 .0 1)。结论 pT12 8可调控的凋亡诱导保证了HIVDNA疫苗足量的抗原表  相似文献   
983.
Methotrexate for the treatment of refractory Crohn's disease.   总被引:4,自引:2,他引:2  
BACKGROUND: Previous studies suggested that methotrexate has beneficial effects in patients with Crohn's disease. We report our experience with this agent in patients with chronic active Crohn's disease who previously failed to improve with conventional treatment, including azathioprine in most cases. METHODS: Between June 1988 and June 1992, 39 patients with refractory Crohn's disease were treated with methotrexate. In patients with active disease, clinical remission was defined by a Harvey-Bradshaw index of less than 4. For patients also taking corticosteroids, the dates of remission and complete steroid withdrawal were recorded. For patients who achieved clinical remission, and those in clinical remission when methotrexate was started, the relapse rate on methotrexate therapy was noted. RESULTS: In the 37 patients with active disease at methotrexate initiation, the probability of remission was 72% at 3 months. The probability of remission and steroid withdrawal was 42% at 12 months. In patients on clinical remission, the probability of relapse on methotrexate was 58% at 12 months. Twenty-two patients experienced side-effects, but these only warranted methotrexate discontinuation in four cases. CONCLUSIONS: Methotrexate appears effective in most patients with refractory Crohn's disease and its short-term toxicity is acceptable, but the long-term benefit seems more limited.  相似文献   
984.
We have generated polyclonal antibodies against the amino-terminal third of the Menkes protein (ATP7A; MNK) by immunizing rabbits with a histidine-tagged MNK fusion construct containing metal-binding domains 1-4. The purified antibodies were used in Western analysis of cell lysates and in indirect immunofluorescence experiments on cultured cells. On Western blots, the antibodies recognized the approximately 165 kDa MNK protein in CHO cells and human fibroblasts. No MNK signal could be detected in fibroblasts from a patient with Menkes disease or in Hep3B hepatocellular carcinoma cells, confirming the specificity of the antibodies. Immunocytochemical analysis of CHO cells and human fibroblasts showed a distinct perinuclear signal corresponding to the pattern of the Golgi complex. This staining pattern was similar to that of alpha-mannosidase II which is a known resident enzyme of the Golgi complex. Using brefeldin A, a fungal inhibitor of protein secretion, we further demonstrated that the MNK protein is localized to the trans- Golgi network. This data provides direct evidence for a subcellular localization of the MNK protein which is similar to the proposed vacuolar localization of Ccc2p, the yeast homolog of MNK and WND (ATP7B), the Wilson disease gene product. In light of the proposed role of MNK both in subcellular copper trafficking and in copper efflux, these data suggest a model for how these two processes are linked and represent an important step in the functional analysis of the MNK protein.   相似文献   
985.
SUMMARY Driven by the need for a readily available, non-immunological tissue that possesses many of the characteristics of normal human skin, tissue-engineered skin has been developed. For over a decade, laboratory grown or processed skin has been under investigation and, in some cases, available as an alternative to autologous grafts. Apligraf, derived from neonatal foreskin and bovine type I collagen, is the first bi-layered living skin equivalent approved in the US and other countries for use in venous ulcers. Apligraf is effective both in the treatment of refractory venous ulcers and for acute wounds such as surgical excision sites and split thickness donor sites. Apligraf is safe and is not clinically rejected. Its ultimate fate is not known, so it may well work to aid healing in a variety of ways including graft ‘take’ and as a stimulus for healing.  相似文献   
986.
987.
988.
4个新2,2-二甲基色烯类化合物的分离和鉴定   总被引:5,自引:0,他引:5  
从三叉苦(Evodia lepta Spr.Mer.)地上部分分离得到5个色烯类化合物,通过光谱解析和化学沟通的方法确定了它们的结构,其中4个为新化合物,依次命名为leptol B(I),ethyleptol B(I),methyleptol B(II)和leptene B(IV),另外1个为已知化合物 methylevodionol(V)。  相似文献   
989.
990.
Summary— Two hundred and nineteen children (boys: 56%, girls: 44%) were included in a randomized, double-blind, multicentre (4 centres) controlled trial designed to assess the efficacy and safety of ibuprofen (IBU) in the treatment of 1 to 6 year-old children with otoscopically proven acute otitis media (AOM), either unilateral or bilateral. They randomly received 10 mg/kg IBU (n = 71), or acetaminophen (PARA) (n = 73) or placebo (PLA) (n = 75), orally, tid, for 48 hours. All received oral cefaclor (Alfatil®, Lilly, France) for seven days. They were evaluated before (D0) and at the end of treatment (D2). The main criterion of response was the aspect (landmarks and color) of the tympanic membrane assessed on a semi-quantitative scale from 0 to 6. Other criteria, assessed on semi-quantitative scales, included relief of pain (0 or 1), rectal temperature (0 to 2), and overall evaluation by parents of the improvement of quality of life on three items: appetite (0 to 2), sleep (0 to 2) and playing activity (0 to 2). The results at D2 were as follows: there was no significant difference between treatment groups as to the main criterion, but only a trend for IBU and PARA to do better than PLA but not for IBU to do better than PARA. From these data there is no argument to emphasize the utility of nonsteroidal anti-inflammatory drugs (NSAIDs) in treating the inflammatory signs of the tympanic membrane in otitis. There was a statistically significant difference between treatment groups at D2 for pain, IBU being superior to PLA (P < 0.01): 7%, 10% and 25% of the children were still suffering at D2 in the IBU, PARA and PLA treatment groups, respectively. The difference between PARA and PLA for pain was not statistically significant. There was no significant difference between treatment groups for the other criteria. All treatments were well and equally tolerated. Although no significant difference was found between the treatment groups on the aspect of the tympanic membrane, the efficacy of IBU was evidenced on the relief of pain, the symptom that most disturbs the child.  相似文献   
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