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71.
The proteasome is the major cellular proteolytic machinery. It is involved in the regulation of various pathways via the selective degradation of either short-lived normal proteins or damaged proteins permitting the cellular detoxification. Proteasome has impaired function during several biological processes, including aging and diseases; however, it can be activated through overexpression of beta(5)- or beta(1)-subunits, resulting to enhanced survival and extended lifespan. In the current study, we have investigated proteasomal up-regulation via overexpression of hUMP1/POMP protein, the known accessory factor for proteasome assembly in humans. hUMP1/POMP overexpressing fibroblasts have increased levels of functional proteasome and enhanced capacity to cope better and faster with various oxidative stressors. These data highlight hUMP1/POMP role in proteasome assembly and further strengthen the prospect of genetic manipulation of the proteasomal system.  相似文献   
72.
目的 检测口服Ag85A DNA疫苗表达产物在脾脏内的分布,为阐明口服DNA疫苗可诱导全身性免疫应答的机制提供依据。方法 将本实验室构建的pCDNA3.1^+-Ag85A真核表达重组质粒转化感受态大肠杆菌DH5α进行扩增,无内毒素抽提纯化,进一步用脂质体包裹制成口服重组Ag85A DNA疫苗。将C57BL/6小鼠随机分为2组,即生理盐水组和DNA疫苗组。分别将生理盐水和Ag85A DNA疫苗以灌胃方式投给各组小鼠,共免疫3次,每次间隔14d,末次免疫后14d处死小鼠,取脾,免疫组化、免疫荧光法检测Ag85A表达产物在脾脏的分布情况。结果 Ag85A重组DNA疫苗的表达产物在小鼠脾脏白髓、边缘区和红髓的脾索处有广泛分布,在边缘区及红髓的脾索处的检出强度高于白髓。免疫组化结果中边缘区与白髓比较t=3.039,P〈0.05;红髓的脾索与白髓比较t=3.068,P〈0.05;边缘区与红髓的脾索比较t=1.750,P〉0.05。免疫荧光结果中边缘区与白髓比较t=3.144,P〈0.05;红髓的脾索与白髓比较t=3.098,P〈0.05;边缘区与红髓的脾索比较t=1.369,P〉0.05。结论口服脂质体包裹的DNA疫苗的表达产物存在于脾脏,表明经口途径接种的DNA疫苗可能会在脾脏诱导全身性免疫应答的产生。  相似文献   
73.
目的:探讨血清鳞状上皮细胞癌相关抗原(SCC—Ag)检测在宫颈鳞癌中的临床意义。方法:用全自动化学发光分析仪检测107例不同临床分期宫颈鳞癌患者血清SCC—Ag的含量,并与对照组进行对比分析。结果:SCC-Ag阳性率随临床分期进展而增高,不同分组之间呈显著性差异(P〈0.01)。SCC—Ag在宫颈鳞癌的表达与临床分期有关(P〈0.01)。结论:SCC—Ag是宫颈鳞癌较特异的肿瘤标志物,对宫颈鳞癌的辅助诊断、治疗效果及预后的判断有较大的价值。  相似文献   
74.
This prospective, randomised clinical trial compared pain, comfort, exudate management, wound healing and safety with Hydrofiber dressing with ionic silver (Hydrofiber Ag dressing) and with povidone-iodine gauze for the treatment of open surgical and traumatic wounds. Patients were treated with Hydrofiber Ag dressing or povidone-iodine gauze for up to 2 weeks. Pain severity was measured with a 10-cm visual analogue scale (VAS). Other parameters were assessed clinically with various scales. Pain VAS scores decreased during dressing removal in both groups, and decreased while the dressing was in place in the Hydrofiber Ag dressing group (n = 35) but not in the povidone-iodine gauze group (n = 32). Pain VAS scores were similar between treatment groups. At final evaluation, Hydrofiber Ag dressing was significantly better than povidone-iodine gauze for overall ability to manage pain (P < 0.001), overall comfort (P < or = 0.001), wound trauma on dressing removal (P = 0.001), exudate handling (P < 0.001) and ease of use (P < or = 0.001). Rates of complete healing at study completion were 23% for Hydrofiber Ag dressing and 9% for povidone-iodine gauze (P = ns). No adverse events were reported with Hydrofiber Ag dressing; one subject discontinued povidone-iodine gauze due to adverse skin reaction. Hydrofiber Ag dressing supported wound healing and reduced overall pain compared with povidone-iodine gauze in the treatment of open surgical wounds requiring an antimicrobial dressing.  相似文献   
75.
The surgical management of a giant omphalocele is challenging. Many cannot be closed at birth and must initially be managed nonoperatively with a topical agent to facilitate epithelialization. We report the case of a term, 1-day-old female neonate with a giant omphalocele treated initially with a hydrofiber dressing containing silver (Aquacel Ag; ConvaTec Inc, Skillman, NJ) and then with delayed primary closure.  相似文献   
76.
MHC class I molecules bind intracellular oligopeptides and present them on the cell surface for CD8+ T‐cell activation and recognition. Strong peptide/MHC class I (pMHC) interactions typically induce the best CD8+ T‐cell responses; however, many immunotherapeutic tumor‐specific peptides bind MHC with low affinity. To overcome this, immunologists can carefully alter peptides for enhanced MHC affinity but often at the cost of decreased T‐cell recognition. A new report published in this issue of the European Journal of Immunology [Eur. J. Immunol. 2013. 43:3051–3060] shows that the substitution of proline at the third residue (p3P) of a common tumor peptide increases pMHC affinity and complex stability while enhancing T‐cell receptor recognition. X‐ray crystallography indicates that stability is generated through newly introduced CH‐π bonding between p3P and a conserved residue (Y159) in the MHC heavy chain. This finding highlights a previously unappreciated role for CH‐π bonding in MHC peptide binding, and importantly, arms immunologists with a novel and possibly general approach for increasing pMHC stability without compromising T‐cell recognition.  相似文献   
77.
本文同时检测了22例急性期脑梗塞患者血浆组织纤溶酶原激活物(t-PA)抑制物(PAI)活性及因子Ⅷ相关抗原(vWF:Ag)含量,结果示三指标与对照组比较,均有显著的增高;并对患者组上述指标与血脂间进行了相关性分析,认为血脂与纤溶系统间的相互联系对动脉粥样硬化、脑血栓形成具有重要意义。  相似文献   
78.
目的 通过结核分支杆菌Ag85B蛋白编码基因在大肠杆菌中稳定表达,以获得大量纯化的Ag85B蛋白。方法 采用DNA重组技术构建结核分支杆菌Ag85B基因的表达载体,双酶切和聚合酶链反应(PCR)鉴定重组子,阳性重组子转化大肠杆菌,并诱导表达外源蛋白。十二烷基磺酸钠聚丙烯酰胺凝胶电泳(SDSPAGE)鉴定Ag85B蛋白抗原在大肠杆菌中的表达,对染色的凝胶扫描,以测定目的蛋白表达水平。结果 菌体蛋白经SDSPAGE,含阳性重组质粒的菌体蛋白中出现一条新蛋白带,表达量占菌体总蛋白的33%~38%。Ag85B蛋白抗原在大肠杆菌中表达方式主要是包涵体形式。结论 构建的大肠杆菌重组体能高效表达结核分支杆菌Ag85B蛋白抗原。  相似文献   
79.
Aminobisphosphonates (NBP) are used for treatment of metastatic bone disease. Frequently, patients undergoing NBP-treatment experience side-effects, known as acute phase response (APR), resulting from cytokine production by Vγ9Vδ2-T cells. As opposed to NBP, statins reduce intracellular phosphoantigen levels and prevent NBP-induced Vγ9Vδ2-T cell activation in vitro. We conducted a pilot study in patients with (bone-)metastasized malignancies receiving NBP-treatment and evaluated the phenotype and function of circulating Vγ9Vδ2-T cells in vivo and the effects of statins on Vγ9Vδ2-T cell responses and the associated APR. We observed reduced expression of perforin, granzyme B and HLA-DR on Vγ9Vδ2-T cells in patients treated with NBP and statins. However, statins could not prevent NBP-induced changes in circulating Vγ9Vδ2-T cell numbers or production of IFNγ and TNFα. Consistent with this, simvastatin could not prevent the occurrence of APR upon NBP-infusion. These observations call for the exploration of alternative strategies to prevent collateral APR upon NBP treatment.  相似文献   
80.
This study compares the utility of two functional assays for von Willebrand factor (VWF), the ristocetin cofactor assay (VWF:RCo) and the collagen-binding assay (VWF:CBA). We analysed a group of 32 patients with type 2 von Willebrand disease (VWD) (25 patients with type 2M, six with type 2A and one with type 2B) and 22 normal control subjects. VWF:RCo/VWF antigen (VWF:Ag) ratios and VWF:CBA/VWF:Ag ratios were compared between the patient and control groups. In the six patients with type 2A VWD, both VWF:RCo/VWF:Ag ratios and VWF:CBA/VWF:Ag ratios were discordant (< or = 0.7). In the 25 type 2M VWD patients, the VWF:CBA/VWF:Ag ratios were concordant (> 0.7), but the VWF:RCo/VWF:CBA ratios were discordant (< or = 0.7) (P = 0.001) compared with control subjects. Thus, VWF:RCo/VWF:Ag ratios were discordant in both type 2M and 2A VWD patient groups indicating a functional abnormality. However, VWF:CBA/VWF:Ag ratios were discordant in the type 2A VWD group but not in the type 2M VWD group. Our study showed that VWF:CBA is sensitive to functional variants associated with the loss of high-molecular-weight multimers, i.e. type 2A and 2B in VWD, but the assay was unable to discriminate defective platelet-binding VWD variants with normal multimeric patterns such as type 2M VWD. It was concluded that the VWF:CBA assay should be used in association with rather than as a replacement for the VWF:RCo assay.  相似文献   
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