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151.
Atypical lipomatous tumor or well-differentiated liposarcoma/dedifferentiated liposarcoma (DDLPS) is the most frequent subtype of malignant adipocytic tumor. This tumor typically presents in late adult life, most commonly in the retroperitoneum, extremities, or spermatic cord. It has been reported that the dedifferentiated component consists mainly of high-grade sarcoma, including undifferentiated pleomorphic sarcoma, fibrosarcoma, and myxofibrosarcoma, and it has been recently reported that the dedifferentiated component can be also made up of a low-grade sarcomatous component. Therefore, the dedifferentiated areas exhibit a wide morphological spectrum that commonly includes fibroblastic/myofibroblastic and fibrohistiocytic tumors but very rarely includes vascular tumors. We present here the first reported case of DDLPS with a hemangioendothelioma-like component in the spermatic cord.  相似文献   
152.
The regulation of the tyrosine phosphorylation of key signaling molecules by tyrosine kinases and phosphatases is essential for BCR-triggered signaling cascades during B cell selection process. We used the non-selective tyrosine phosphatase inhibitor vanadate to study the importance of the late regulation of the tyrosine phosphorylation for BCR-triggered G1 growth arrest and apoptosis in Ramos-BL B cells. Vanadate induces G2M growth arrest in a dose-dependent manner and prevents BCR-triggered apoptosis. Vanadate-induced upregulation of the tyrosine phosphorylation is concomitant with increased expression of cyclin B and inhibition of caspase-3 activation and PARP cleavage. The anti-apoptotic effect of vanadate was observed even when added up to 6 hours after the treatment of Ramos-BL B cells with anti-IgM. Vanadate increases BCR-triggered tyrosine phosphorylation of the cytosolic tyrosine phosphatases, SHP-1 and SHP-2 after 24 hours. Co-stimulation with anti-CD40 prevents anti-IgM-triggered tyrosine phosphorylation of these phosphatases and up-regulates the expression of SHP-1. We conclude that the regulation of the tyrosine phosphatase activity is indispensable for BCR-triggered execution of the apoptosis in Ramos-BL B cells.  相似文献   
153.
CD40 stimulation has produced impressive results in early-stage clinical trials of patients with cancer. Further progress will be facilitated by a better understanding of how the CD40 receptor becomes activated and the subsequent functions of CD40-stimulated immune cells. This review focuses on two aspects of this subject. The first is the recent recognition that signaling by CD40 is initiated when the receptors are induced to cluster within the membrane of responding cells. This requirement for CD40 clustering explains the stimulatory effects of certain anti-CD40 antibodies and the activity of many-trimer, but not one-trimer, forms of CD40 ligand (CD40L, CD154). The second topic is the use of these CD40 activators to expand B cells (“CD40-B cells”). As antigen-presenting cells (APCs), CD40-B cells are as effective as dendritic cells, with the important difference that CD40 B cells can be induced to proliferate in vitro, whereas DCs proliferate poorly if at all. As a result, the use of CD40-B cells as antigen-presenting cells (APCs) promises to streamline the generation of anti-tumor CD8+ T cells for the adoptive cell therapy (ACT) of cancer.  相似文献   
154.
155.
The present study investigates whether lymphatic vessel invasion (LVI) detected by D2‐40 staining is a prognostic factor for stage I adenocarcinoma of the lung. We retrospectively reviewed 124 patients who underwent complete resection for stage I adenocarcinoma of the lung from January 1983 to June 2003. LVI was microscopically evaluated using D2‐40 immunostaining. The median follow‐up was 71 months. The LVI positive rate was 37%. The 5‐year cancer‐specific survival rates of the D2‐40 positive LVI and negative groups were 88.8% and 84.3%, respectively (P = 0.630). The stage I lung adenocarcinoma patients who were determined to be LVI positive based on D2‐40 immunostaining did not have a significantly poorer prognosis than the LVI negative cases. Thus, lymphatic microinvasion may not be a prognostic indicator in early lung cancer, although advanced LVI does appear to correlate with survival. It is therefore unnecessary to use D2‐40 immunostaining to diagnose LVI in practical settings, and Hematoxylin‐Eosin and Elastica van Gieson staining should continue to be used to predict the prognosis of patients with stage I lung adenocarcinoma.  相似文献   
156.
Cryopreservation of hematopoietic stem cells (HSC) involves slow rate cooling in the presence of a cryoprotectant (DMSO) to avoid the damaging effects of intracellular ice formation. The infusion of DMSO with the thawed product has been related to adverse events. Reduction of DMSO content by washing the HSCs after thawing has been suggested as a method to avoid infusion-related side-effects. Albumin-dextran washing methods have proved useful in thawing HSC products. Dextran40 shortages prompted us to search for suitable alternatives. We report the results of a comparative study of the use of hydroxyethyl starch (HES) as an alternative to dextran40 for washing thawed HSCs products. A total of 10 HSC bags cryopreserved with 10 % DMSO were used. We conducted a paired study; one of the bags was thawed and washed with our standard washing solution (Dextran 40) and the paired bag with HES solution with a final HES and Human Serum Albumin (HSA) concentration of 2.4 % and 4.2 % respectively. Each final product was tested immediately after washing (sample 0’) and after 90 min (sample 90’) for total nucleated cells (TNC) recovery, acridine orange viability, viable CD34+ enumeration, and clonogenicity. No significant difference was found for any of the cell counts, viability tests, cell recovery, or potency. We can state that the washing solution based on 2.4 % HES and 4.2 % HSA is equivalent to that used in our routine practice. Therefore, we could use the solution with HES, paying special attention to the renal function of the recipient.  相似文献   
157.
目的:研究活血化瘀养心通络方辅助治疗冠心病PCI术后心绞痛患者实验室指标血清人软骨糖蛋白(YKL-40)、超敏C反应蛋白(hs-CRP)等炎症因子水平及临床疗效的影响。方法:选取2018年3月到2019年6月某院心内科收治的冠心病PCI术后再发心绞痛患者。随机分为治疗组与对照组各50例。2组均给予常规西医药物治疗,治疗组在西医药物治疗基础上增加活血化瘀养心通络方治疗。观察治疗后硝酸甘油停减率、治疗前后YKL-40、hs-CRP水平、肿瘤坏死因子(TNF-α)、白介素-6(IL-6)、临床疗效及中医证候积分。结果:治疗后治疗组硝酸甘油停减率明显高于对照组(P<0.05)。2组治疗后YKL-40、hsCRP、TNF-α、IL-6水平均明显分别低于本组治疗前(P<0.05);治疗后治疗组YKL-40、hsCRP、TNF-α、IL-6水平均明显低于对照组(P<0.05)。治疗后治疗组显效率76.00%(38/50)明显高于对照组42.00%(21/50)(P<0.05)。2组治疗后中医证候积分均明显分别低于本组治疗前(P<0.05);治疗后治疗组中医证候积分明显低于对照组(P<0.05)。结论:在常规西医药物基础上增加活血化瘀养心通络方治疗可更显著改善冠心病PCI术后再发心绞痛患者心绞痛症状,促进相关实验室指标恢复正常。  相似文献   
158.
丹参对右旋葡聚糖硫酸钠诱导小鼠结肠炎的疗效观察   总被引:4,自引:0,他引:4  
目的 :评价丹参预防及治疗右旋葡聚糖硫酸钠 (DSS)结肠炎小鼠的有效性。方法 :2 0只正常小鼠随机分为两组 ,饮用 DSS7d,同时预防组用丹参 ,对照组用 0 .85 %氯化钠溶液。另 2 0只 DSS诱导的结肠炎小鼠随机分为两组 ,治疗组用丹参 ,对照组用 0 .85 %氯化钠溶液 7d。用疾病活动指数 (DAI)、组织学评分和马休斯猩红蓝(MSB)纤维素染色检测微血栓以评价疗效。结果 :丹参在预防组部分降低微血栓的形成 ,对照组 10例有 6例微血栓阳性 ,预防组 3例阳性。丹参治疗组与对照组的 DAI、直肠、横结肠组织学评分分别为 0 .4 5、0 .4 8(P>0 .0 5 ) ,1.36、1.76 (P<0 .0 5 ) ,1.35、1.6 0 (P<0 .0 5 )。结论 :丹参可能部分抑制微血栓形成和减轻 DSS结肠炎小鼠结肠炎症 ,提示丹参用于溃疡性结肠炎治疗也可能有效。  相似文献   
159.
Immunostimulatory DNA ameliorates experimental and spontaneous murine colitis   总被引:23,自引:0,他引:23  
BACKGROUND & AIMS: Impaired mucosal barrier, cytokine imbalance, and dysregulated CD4(+) T cells play important roles in the pathogenesis of experimental colitis and human inflammatory bowel disease. Immunostimulatory DNA sequences (ISS-DNA) and their synthetic oligonucleotide analogs (ISS-ODNs) are derived from bacterial DNA, are potent activators of innate immunity at systemic and mucosal sites, and can rescue cells from death inflicted by different agents. We hypothesized that these combined effects of ISS-DNA could inhibit the damage to the colonic mucosa in chemically induced colitis and thereby limit subsequent intestinal inflammation. METHODS: The protective and the anti-inflammatory effect of ISS-ODN administration were assessed in dextran sodium sulfate-induced colitis and in 2 models of hapten-induced colitis in Balb/c mice. Similarly, these effects of ISS-ODN were assessed in spontaneous colitis occurring in IL-10 knockout mice. RESULTS: In all models of experimental and spontaneous colitis examined, ISS-ODN administration ameliorated clinical, biochemical, and histologic scores of colonic inflammation. ISS-ODN administration inhibited the induction of colonic proinflammatory cytokines and chemokines and suppressed the induction of colonic matrix metalloproteinases in both dextran sodium sulfate- and hapten-induced colitis. CONCLUSIONS: As the colon is continuously exposed to bacterial DNA, these findings suggest a physiologic, anti-inflammatory role for immunostimulatory DNA in the GI tract. Immunostimulatory DNA deserves further evaluation for the treatment of human inflammatory bowel disease.  相似文献   
160.
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