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91.
目的 建立检测EBV感染的新方法并观察EBV与鼻咽癌的关系。方法 鼻咽部活检组织和石蜡包埋标本6 6例 ,采用荧光定量聚合酶链反应 (FQ -PCR)和原位杂交 (ISH)两种方法检测EBV ,其检测结果与病理诊断对照。结果 :FQ-PCR检测EBV -DNA阴性 5 2例 ,其中 5 1例为炎性病变 ,另 1例为腺癌 ;EBV -DNA阳性 14例 ,其中 13例为鳞状细胞癌 ,另 1例虽为炎症。但部分上皮细胞呈不典型增生。ISH检测EBV阳性 4 9例 ,其中 4 7例为炎性病变 2例为癌。EBV阳性 17例 ,其中 12例为癌 ,5例为炎性病变。FQ -PCR和ISH检测EBV结果 ,经卡方检测差异无显著性 (P >0 .0 5 )。结论 EBV感染与鼻咽癌有高度相关性。FQ -PCR检测EBV具有方法简单、快速、定量准确等优点。 相似文献
92.
Zou Jian-Ping; Yamamoto Norihiko; Fujii Tetsuya; Takenaka Hiroshi; Kobayashi Michiko; Herrmann Steven H.; Wolf Stanley F.; Fujiwara Hiromi; Hamaoka Toshiyuki 《International immunology》1995,7(7):1135-1145
Unfractionated spleen cells taken from tumor-bearing mice 2weeks after tumor implantation contained tumor-primed T cellswhich produced cytokines including IL-2 and IFN- when culturedin vitro. With progressive tumor growth this initial lymphokine-producingcapacity decreased. Here, we investigated the ability of IL-12to (I) restore suppressed IFN- production, (II) cause tumorregression and (II) induce anti-tumor protective immunity. Additionof rIL-12 to spleen cell cultures from 4- to 10-week-old tumor-bearingmice resulted in a striking enhancement in the production ofIFN- compared with cultures of these cells in the absence ofrIL-12 or of normal spleen cells in the presence of rIL-12.Five I.p. injections of rIL-12 into mice bearing s.c. tumorsinduced complete tumor regression. This was found when rIL-12was given at early (1–2 weeks), intermediate (4–5weeks) or even late (7 weeks) stages of tumor growth. Furthermore,IL-12-treated mice which rejected the primary tumor exhibitedcomplete resistance to a rechallenge with the same tumor butdid not reject a second syngenetic tumor. Immunohistochemicalanalyses following IL-12 treatment revealed that CD4+ and CD8+T cells infiltrate the tumor. More importantly, IFN- mRNA expressionwas observed in fresh tumor masses from tumor-bearing mice receivingIL-12 treatment The importance of IFN- was further demonstratedby the observation that the systemic administration of anti-IFN-mAb prior to IL-12 treatment completely abrogated the anti-tumoreffect of IL-12. Thus, these results indicate that administrationof modest levels of rIL-12 to tumor-bearing mice results intumor regression through mechanisms involving reversal of suppressedIFN- production by anti-tumor T cells and the establishmentof a tumor-specific protective immune response. 相似文献
93.
A new type of polysaccharide host, carboxymethyl-histaminocarbonylmethylamylose ( 2b ), containing carboxylic, imidazolyl and hydroxyl groups in the backbone, was used as a mimetic system for chymotrypsin in the catalytic hydrolysis of 3-acetoxy-N-dodecylpyridinium iodide ( 1 ). The substrate is located in the hydrophobic cavity of the amylose helix. The apparent saturation, the entropy-favored kinetics and the pronounced catalytic efficiency (9 times higher than that of a system consisting of the same concentration of carboxymethylamylose and histamine) show that 2b is a good enzyme model in which the definite binding site, active center and self-organization characteristics are present. Most distinctly, the pH-rate constant profile of the hydrolysis of 1 and 2b is of bell-type and has an optimum at pH 7,98, which is very close to 7,90 for chymotrypsin. In conclusion, the charge relay mechanism is also involved in the catalytic effect of 2b . 相似文献
94.
认知疗法治疗强迫症的对照研究 总被引:2,自引:0,他引:2
目的 探讨认知疗法治疗强迫症的疗效。方法 对 6 0例符合 CCMD-2 -R诊断标准 ,且 Y-BOCS量表评分≥ 1 6分的强迫症病人 ,随机分到认知治疗组 ( 30例 )和氯丙咪嗪组 ( 30例 ) ,两组在氯丙咪嗪常规治疗的同时 ,其中一组加用认知治疗 ,共治疗 8周。在治疗前、后两组均进行临床疗效评估和 Y-BOCS量表评分。结果 认知治疗组痊愈 1 1例、显效 1 6例、有效 3例。氯丙咪嗪组痊愈 6例、显效 1 4例、有效 1 0例。两组痊愈和显效比较有显著差异 ( P<0 .0 5 )。 Y-BOCS量表减分率 :认知治疗组 5 4 .90 % ,氯丙咪嗪组 4 2 .33% ,两组比较有显著差异 ( P<0 .0 5 )。结论 认知疗法配合药物治疗强迫症比单用氯丙咪嗪治疗强迫症疗效更好 相似文献
95.
96.
本实验在40只大鼠经伺服零测压技术测定的肾脏微血管内压力分布及其ANP的作用均随血管树各段的口径变化而改变。分析小球前各段血管的压力降所占动脉总压降的比例得知:小叶间动脉占总压降的88%。肾小球毛细血管和出球小动脉亦具有较大的压力降。正常对照情况下,肾小球前血管内的压力分布与内径呈直线相关(r=0.869,n=65,P<0.01),其回归方程为平均压()=34.71±0.798×血管内径(D)。给ANP后肾小球前血管内的压力与内径仍呈直线相关(r=0.931,P<0.01),回归方程式为()=38.53+0.765D,其曲线右上移。本文结果提示,肾小球前微血管内压力分布与血管内径密切相关。小叶间动脉的阻力较大。 相似文献
97.
目的:探讨升压治疗局灶性脑缺血的保护作用及治疗的维持时间。方法:采用大鼠局灶性脑缺血再灌注模型,40只大鼠随机分为五组:模型对照组(A)、升压维持15min组(B)、维持45min组(C)、维持90min组(D)和120min组(E),观察各组神经功能评分、脑梗死体积和病理学改变。结果:神经功能缺损评分B、C、D组明显低于A组;B、C、D、E各组脑梗死体积明显低于A组,C、D、E组明显低于B组;各治疗组组织病理学改变比对照组轻,B组最轻。结论:缺血3h再灌注时,升压维持时间在2h以内对脑损伤有保护作用,升压最佳维持时间是15min。 相似文献
98.
Telomerase and cancer 总被引:35,自引:0,他引:35
99.
目的:研究黄体激素释放激素(Luteinizinghormone releasinghormone,LHRH)在大鼠体内的药动学规律。方法:用氯胺T法将125I标记到LHRH分子上(放化纯度96.2%),14只SD大鼠随机分为大剂量、小剂量组,每组7只,分别肌肉注射125I LHRH(小剂量组0.5mg.kg,大剂量组1.00mg.kg),给药后在21个不同时间点逐一取各鼠尾动脉血做放射性测定。结果:大鼠试验结果显示,大剂量组t1/2平均为67.83±20.84h;小剂量组半衰期平均为64.68±22.90h。LHRH的药—时曲线符合二室模型,大剂量LHRH和小剂量LHRH的主要药动学指标差别不大。结论:LHRH在大鼠体内的消除模式为二室模型,为一级动力学消除。 相似文献
100.
Vickers SM Johnson LL Zou LQ Yannas IV Gibson LJ Spector M 《Tissue engineering》2004,10(7-8):1214-1223
Cells derived from synovium have drawn interest as donor cells for articular cartilage tissue engineering because they have been implicated in certain cartilage repair processes in vivo and the chondrogenic potential of the cells has been demonstrated in vitro. Studies have demonstrated that several other types of musculoskeletal connective tissue cells--including chondrocytes, fibrochondrocytes, ligament fibroblasts and osteoblasts, and mesenchymal stem cells can express the gene for the contractile actin isoform, alpha-smooth muscle actin (SMA), and can contract analogs of extracellular matrix in vitro. Although the physiological roles of SMA-enabled contraction of these cells have yet to be established, cell-mediated contraction of scaffolds employed for tissue engineering can alter the pore diameter of the matrix and distort its overall shape, and thus needs to be addressed. Toward this goal, the objective of this study was to investigate the expression of SMA by synovial cells and to evaluate their contraction of collagen-glycosaminoglycan (GAG) scaffolds. Synovial membranes obtained from the knees (stifle joints) of six adult dogs were evaluated for the presence of SMA by immunohistochemistry. Cells isolated from the synovial tissue were expanded through seven passages in monolayer culture, with samples from each passage allocated for Western blot analysis of SMA. Cells from passage 4 were seeded into porous type I collagen-GAG matrices and cultured for 4 weeks. Synovial cell-mediated contraction of the scaffolds was determined by measuring the diameters of the cell-seeded scaffolds and nonseeded controls every other day. Synovium-derived cells cultured as micropellets or in collagen-GAG matrices were incubated in chondrogenic medium with and without fetal bovine serum and evaluated for chondrogenesis by type II collagen immunohistochemistry. Immunohistochemistry revealed the presence of SMA in some cells (less than 10% of the cells) in the intimal layer of synovium from four of the five animals analyzed. Western blot analysis demonstrated a regular increase in the amount of SMA in the synovium-derived cells with passage number. Synovial cell-mediated contraction of the collagen-GAG scaffolds reached a value of 43% of the original diameter after 4 weeks, comparable to that found with other musculoskeletal cell types. Incubation of micropellet cultures of synovium-derived cells with chondrogenic medium revealed trace amounts of type II collagen production by immunohistochemistry. The findings of this study indicate that control of SMA-enabled contraction may be important when employing synovial cells for cartilage repair procedures, and warrant further investigation into the physiological role of SMA expression in synovial cells. 相似文献