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21.
目的初步探讨血管生成素-2(Angiopoietin-2,Ang-2)在食管鳞状细胞癌组织中的表达及其与肿瘤病理分级、浸润和转移的关系。方法采用S-P免疫组织化学方法,对85例食管鳞癌及22例正常食管组织中的Ang-2表达水平进行检测,并与肿瘤病理分级、浸润深度及淋巴结转移情况进行统计学分析。结果85例食管鳞癌组织中,57例Ang-2表达呈阳性,阳性率为67.06%,显著高于Ang-2在正常食管组织中的表达(P<0.05)。Ang-2表达与肿瘤病理分级和淋巴结转移显著相关(P<0.05)。结论Ang-2的表达与食管鳞癌的临床分期及病理分级呈正相关,提示Ang-2促进肿瘤新生血管形成,参与食管鳞癌的发生和发展,可作为反映食管癌进展的生物学指标。  相似文献   
22.
中期因子在胰腺癌组织中的定位与表达特点   总被引:1,自引:1,他引:0  
目的 探讨中期因子(MK)的mRNA及其蛋白在胰腺癌(PC)组织中的定位与表达特点。方法采用原位杂交和免疫组织化学方法检测52例PC、12例慢性胰腺炎及6例正常胰腺组织中MK mRNA及蛋白的定位与表达水平。结果MK mRNA及蛋白水平在PC组织均呈过度表达,表达阳性率分别为71.2%和73.1%,都定位于PC细胞质,有淋巴结转移和Ⅱ-Ⅳ期的患者,MK阳性表达率明显高于无淋巴结转移和Ⅰ期患者(P<0.01)。在PC细胞外组织中也有MK表达,尤其在血管密集处明显。而在慢性胰腺炎及正常胰腺组织中MK表达阴性。结论 MK mR-NA及其蛋白在PC组织中呈过度表达,并可能与促进PC血管生成和转移有关。检测MK表达情况可作为PC的辅助诊断指标之一。  相似文献   
23.
目的 探讨环氧合酶 (COX) 2与肝细胞癌血管形成的关系。方法 利用免疫组织化学、Westernblot方法检测 48例肝癌组织中COX 2和血管内皮生长因子 (VEGF)蛋白及逆转录 聚合酶链反应法 (RT PCR)检测COX 2和VEGFmRNA的共表达 ,对共表达COX 2和VEGF蛋白和mRNA的肝癌组织进行微血管记数。结果 免疫组织化学检测中 ,48例肝癌组织 3 6例共表达COX 2和VEGF蛋白。类似结果见于蛋白电泳分析。RT PCR显示 ,48例肝癌组织 3 6例共表达COX 2mRNA和VEGFmRNA。两者之间的表达明显相关 (γ =0 .845 )。共表达COX 2和VEGF蛋白和mRNA的肝癌组织中 ,平均微血管数 (5 6.8± 17.5 )个 ,明显高于阴性表达组。结论 COX 2可能与肝细胞癌的血管形成有关 ,且其作用之一可能是通过上调VEGF通道来发挥的  相似文献   
24.
The role of angiogenesis in multiple myeloma (MM) pathogenesis is well established. Angiogenesis is linked to the functional state of endothelial junctions that are modulated by the growth and activation of endothelial cells. CD146 and vascular endothelial‐cadherin (VE‐cadherin) are cell adhesion molecules localized at the endothelial junction. The aim of the study was to assess sVE‐cadherin and sCD146 serum levels in MM patients. Forty‐six untreated patients with MM were included in this study. In addition, 23 of 46 patients were analyzed again in partial remission after initial chemotherapy. Twenty‐two samples from healthy volunteers were evaluated as the control. There was no significant difference in sCD146 level between MM patients and the control (511 ± 177.2 vs. 460.9 ± 156.9 ng/ml respectively). In untreated MM patients, sVE‐cadherin level was significantly higher than in the control (1.36 ± 0.55 vs. 0.63 ± 0.56 ng/ml respectively; P < 0.05). In untreated MM patients, sVE‐cadherin level was significantly higher than in MM patients in partial remission (1.36 ± 0.55 vs. 0.5 ± 0.33 respectively; P < 0.05). sVE‐cadherin but not sCD146 serum level was increased in untreated MM patients and decreases after chemotherapy in patients in partial remission. VE‐cadherin may reflect intensity of angiogenesis in MM and may be useful in prognosis of response to treatment.  相似文献   
25.
MMP-2、TIMP-2、VEGF和bFGF在血管瘤增生及消退过程中的变化   总被引:1,自引:0,他引:1  
目的 探讨基质金属蛋白酶-2(MMP-2)及其抑制剂(TIMP-2)、血管内皮生长因子(VEGF)和碱性成纤维细胞生长因子(bFGF)在血管瘤增生、消退过程中的变化。方法 采用免疫组织化学链霉亲和素-过氧化酶(SP)法,检测增生期血管瘤32例、消退期血管瘤10例、血管畸形17例及小儿正常皮肤10例标本中MMP-2、TIMP-2、VEGF及bFGF的表达。结果 MMP-2、VEGF及bFGF在增生期血管瘤中的表达明显高于消退期血管瘤、血管畸形和正常皮肤,其差异有统计学意义;TIMP-2在消退期血管瘤中的表达明显高于增生期血管瘤、血管畸形和正常皮肤,其差异有统计学意义。结论 MMP-2、VEGF及bFGF可能促进血管瘤血管生成,从而促进血管瘤增生,而TIMP-2可能促进血管瘤消退。  相似文献   
26.
TNP-470对裸鼠体内人结肠癌细胞增殖和凋亡的影响   总被引:1,自引:0,他引:1  
目的 研究TNP-470对裸鼠体内人结肠癌细胞增殖和凋亡的影响。方法 将16只人结肠癌皮下移植瘤裸鼠随机分成实验组和对照组,实验组隔日予以TNP-47030mg/kg,皮下注射,对照组予以相同体积的生理盐水,4周后处死,应用免疫组织化学法(免疫组化)和图象分析技术检测肿瘤细胞中增殖细胞核抗原(PCNA)的表达,TdT介导的dUTP缺口末端标记(TUNEL)法检测肿瘤细胞的凋亡,透射电镜观察凋亡细胞的超微结构。结果 TNP-470明显抑制了肿瘤的生长,抑瘤率为45.53%。实验组肿瘤中PCNA的表达显低于对照组,凋亡指数上升,电镜下可见典型的细胞凋亡形态学变化。结论 TNP-470除了通过抗血管生成作用抑制肿瘤生长外,还可通过抑制LOVO细胞本身的增殖和诱导凋亡发挥抗肿瘤作用。  相似文献   
27.
Methods: Gene therapy was tested for inducing functional angiogenesis in the superficial rat epigastric island flap to allow earlier pedicle division. Autologous rat fibroblasts were grown, harvested, cultured and retrovirally transfected to produce platelet-derived growth factor AA (PDGF-AA), an angiogenetically active protein. Stable gene expression was monitored by PDGF-AA enzyme-linked immunosorbent assay (ELISA). One hundred and eighty animals were divided into three groups (I–III) and a bilateral flap created in each animal. In all experiments, the right-sided flap was subjected to experimental treatment and the left-sided flap served as control (1 ml saline 0.9%). During flap elevation, group I received 5×106 GMFB (genetically modified fibroblasts) plus 1 ml Dul-becco's modified Eagle's medium. Group II was treated with 5×106 NMFB (non-modified fibroblasts) plus 1 ml medium and group III received 1 ml medium only. The flaps were sutured back and the vascular pedicle was bilaterally ligated and divided in each of ten animals during the following 6 days. After 7 days, the flaps were harvested, the amount of necrosis measured and histologically examined. Results: The GMFB produced up to 560 times more PDGF-AA than the NMFB, measured by ELISA. The GMFB-treated flaps tolerated surgical division of the vascular pedicle significantly earlier than groups II and III. Histologically, fibroblasts persisted in all flaps of groups I and II, without major inflammatory reaction. In all GMFB-treated flaps, massive angiogenesis could be demonstrated. Conclusion: By means of retroviral gene transfer, autologous rat fibroblasts can be genetically modified for stable expression of the PDGF-A gene to produce high amounts of PDGF-AA, which is angiogenetically active. After injection into the panniculus carnosus, these cells induce functional angiogenesis to permit earlier division of the vascular pedicle in this flap model. Received: 5 January 1998 / Accepted: 17 June 1998  相似文献   
28.
Marked neovascularization is a hallmark of many neoplasms in the nervous system. Recent reports indicate that the endothelial mitogen vascular endothelial growth factor (VEGF) may play a critical role in the regulation of vascular endothelial proliferation in malignant gliomas. Using novel monoclonal antibodies to the VEGF polypeptide we have determined the expression and cellular distribution of VEGF protein in a representative series of 171 human central nervous system (CNS) tumors by immunohistochemistry and immunoblotting. In agreement with previous in situ hybridization data, 19 out of 20 glioblastomas (95%) showed immunoreactivity for VEGF, whereas both the percentage of immunoreactive tumors and the extent of immunoreactivity for VEGF were significantly lower in astrocytomas. Of the pilocytic astrocytomas (WHO grade I) 44% were immunoreactive for VEGF, but we observed several cases with pronounced vascular proliferates in the absence of VEGF. In ependymomas, meningiomas, hemangioblastomas, and primitive neuroectodermal tumors, there was no correlation between VEGF expression, vascular endothelial proliferation and the grade of malignancy. Oligodendrogliomas and the oligodendroglial component of mixed gliomas lacked immunoreactive VEGF, indicating that endothelial growth factors other than VEGF may regulate tumor angiogenesis in these neoplasms. Western blot analysis showed a predominant VEGF protein species of 23 kDa and confirmed the immunohistochemical data in all cases. Our findings demonstrate that VEGF is expressed in a wide spectrum of brain tumors in which it may induce neovascularization. However, other angiogenic factors also appear to contribute to the vascularization of CNS neoplasms. Received: 18 April 1996 / Revised, accepted: 20 August 1996  相似文献   
29.
Solid and suspension grafts of fetal central nervous system (CNS) tissue rapidly reform an intact blood-brain barrier (BBB), whereas solid grafts of peripheral nervous system (PNS) tissue fail to establish a BBB as detected by horseradish peroxide (HRP) leakage, administrated intravenously. We examined the acute changes in the BBB after grafting of fetal CNS tissue in solid and suspension form and superior cervical ganglion (SCG) and PNS tissue in the same manner. Adult rats (n = 20) received fetal (day 14–15) forebrain grafts (either solid or cell suspension) to their rostral corpus callosum bilaterally. A second group (n = 20) received SCG solid and cell suspension grafts at the same coordinates with the same technique. The animals were killed on first, third, seventh, and tenth days after grafting. Intravenous HRP (Sigma, type VI, 75 mg/5-g rat) was given 1 hour before perfusion with mixed aldehydes. Fifty-micron coronal sections were examined for the presence and location of the graft by cresyl violet and AChE staining and Mesulam's TMB method to detect HRP leakage. HRP leakage was detected in the parenchyma in all groups on the first and the third days post-transplantation indicating a disrupted BBB. No HRP reaction was seen at days 7 and 10 in groups receiving fetal forebrain tissue whether solid or cell suspension. Solid grafts of SCG consistently demonstrated HRP leakage from the first through the tenth day. However, cell suspension of SCG established a BBB by 7 days. These results suggest that within the solid grafts of CNS and PNS tissue, the permeability of the vessels is dictated by the transplanted tissue itself. When cell suspensions of the same tissue are introduced, host CNS tissue dominates as the local environment resulting in non-leaky vasculature within the graft.  相似文献   
30.
目的 观察原发性食管癌中胸苷磷酸化酶 (thymidinephosphorylase,TP)的表达情况 ,探讨肿瘤组织中胸苷磷酸化酶表达、肿瘤微血管密度 (microvesseldensity ,MVD)和临床病理特征之间的关系 ,分析TP表达和肿瘤MVD的预后意义。方法 应用单克隆抗体对 6 5例食管癌标本进行免疫组化染色 ,测定TP表达及MVD。结果 TP在食管癌中的表达 (4 5 / 6 5 ,6 9.2 % )明显 (P <0 .0 0 1)高于正常食管粘膜 (4 / 2 4 ,16 .7% )。食管癌的MVD(4 5 .0 9± 8.76 )与正常食管粘膜的MVD(2 7.4 8± 8.4 4 )的差别显著 (P <0 .0 0 1)。食管癌TP阳性的MVD的均值是 (4 6 .5 3± 7.18) ,TP阴性的MVD的均值是 (4 1.85± 11.0 8) ,前者明显 (P =0 .0 4 6 ) 高于后者。食管癌的TP表达与临床病理特征无相关性 ,MVD却与肿瘤的浸润深度(P =0 .0 35 ) 及分期(P =0 .0 18) 有关 ,而且只有MVD才是食管癌的一个预后指标(P <0 .0 0 1)。结论 食管癌的TP表达与MVD密切相关。TP表达与食管癌的临床病理特征无关。MVD与肿瘤的浸润发展有关 ,同时只有MVD才是食管癌的一个预后指标  相似文献   
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