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961.
胃小凹及微血管形态变化对胃良恶性溃疡的诊断价值   总被引:1,自引:0,他引:1  
目的探讨放大内镜下溃疡边缘黏膜小凹形态及黏膜微血管等微细结构对胃良恶性溃疡的诊断价值。方法Pentax EG-3430Z型放大胃镜对158例溃疡病患者,先行常规检查,后利用其放大功能观察溃疡边缘胃小凹及黏膜微血管改变,于相应部位内镜下活检,行病理组织学检查。结果良性溃疡胃小凹形态规则,34.4%及67.7%患者呈C型和D型,93.8%恶性溃疡患者胃小凹呈E型,形态不规则,大小不一,良恶性溃疡小凹形态差异有统计学意义(x^2=103.888,P〈0.01);良性溃疡中,69.9%患者可见规则毛细血管网,恶性溃疡患者中,80%患者可见黏膜微血管不规则如迂曲、变形、融合等现象,29.2%的患者可见粗大的肿瘤血管,微血管形态差异有统计学意义(x^2=130.963,P〈0.01);黏膜小凹形态及微血管微细结构变化对恶性溃疡的诊断具有较高的灵敏性和特异性。结论放大内镜下胃小凹及黏膜微血管变化对良恶性溃疡的诊断、鉴别及早期胃癌的发现有重要意义。  相似文献   
962.
BackgroundPatients with early-stage lung cancer who underwent R0 resection often encounter disease recurrence, especially during the early phase; thus, it is deemed vital to determine the predictive factors for recurrence after surgery. In this study, we aimed to identify the independent variables associated with recurrence after complete surgical resection of pathological stage I lung adenocarcinoma.MethodsWe retrospectively reviewed the medical records of 169 patients who underwent pulmonary resection for primary lung adenocarcinoma pathological stage I with curative intent lung cancer surgery from 2015 to December 2018 at our institution for information on the recurrence of the disease.ResultsPer the multivariate analysis, the presence of micropapillary pattern and vessel invasion were found to be independent predictors of disease recurrence after surgery (odds ratio [OR]: 9.36, 95% confidence interval [CI]: 2.42–36.2, P = 0.0012; and OR: 4.50, 95% CI: 1.52–13.4, P = 0.0068, respectively). Vessel invasion was also found to be an independent predictor of disease recurrence after surgery within a year (OR 11.4, 95% CI 3.08–42.5, P = 0.0003).ConclusionsThe presence of vessel invasion may help in distinguishing patients with the highest risk of early-phase disease recurrence after surgery. Patients with stage I adenocarcinoma with vessel invasion should undergo intensive surveillance after surgery.  相似文献   
963.
Introduction and objectivesThe index of microcirculatory resistance (IMR) measured after primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) is associated with microvascular obstruction (MVO) and adverse clinical events. To evaluate MVO after successful primary PCI for STEMI without pressure wires or hyperemic agents, we investigated the feasibility and usefulness of functional angiography-derived IMR (angio-IMR).MethodsThe current study included a total of 285 STEMI patients who underwent primary PCI and cardiac magnetic resonance (CMR). Angio-IMR of the culprit vessel after successful primary PCI was calculated using commercial software. MVO, infarct size, and myocardial salvage index were assessed using CMR, which was obtained a median of 3.0 days [interquartile range, 3.0-5.0] after primary PCI.ResultsAmong the total population, 154 patients (54.0%) showed elevated angio-IMR (> 40 U) in the culprit vessel. MVO was significantly more prevalent in patients with angio-IMR > 40 U than in those with angio-IMR ≤ 40 U (88.3% vs 32.1%, P < .001). Infarct size, extent of MVO, and area at risk were significantly larger in patients with angio-IMR > 40 U than in those with angio-IMR ≤ 40 U (P < .001 for all). Angio-IMR showed a significantly higher discriminatory ability for the presence of MVO than thrombolysis in myocardial infarction flow grade or myocardial blush grade (area under the curve: 0.821, 0.504, and 0.496, respectively, P < .001).ConclusionsAngio-IMR was significantly associated with CMR-derived infarct size, extent of MVO, and area at risk. An elevated angio-IMR (> 40 U) after primary PCI for STEMI was highly predictive of the presence of MVO in CMR.This trial was registered at ClnicalTrialsgov (Identifier: NCT04828681).  相似文献   
964.
目的:膜研究膜型-1基质金属蛋白酶(MT1- MMP)反义RNA对人胃癌细胞BGC823靶基因表达和侵袭特性的影响方法:利用基因重组技术构建人MT1-MMP反义RNA真核表达载体,转染人胃癌细胞BGC823,应用RT-PCR、MTT、明胶酶谱和体外侵袭实验等方法观察人胃癌细胞BGC823转染前后,MT1-MMP mRNA表达水平、细胞生长、明教酶A活性及细胞体外侵袭能力等指标的变化.结果:成功构建了MT1-MMP反义RNA真核表达载体pasMMP14,将其转染胃癌细胞BGC823后,与阴性对照组相比,实验组MT1- MMP mRNA表达水平降低,抑制率为36%.转染48 h,明教酶A的活化受到了明显抑制.转染72 h,细胞增殖明显受抑(t=2.358,P<0.01 vs空白组:t=2.727 P<0.01 vs阴性组).实验组的穿膜细胞数明显低于空白对照组和阴性对照组(t=5.744,P<0.01;t=5.695,P<0.01).结论:反义RNA对人胃癌细胞MT1-MMP基因表达和侵袭能力具有明显的抑制作用,MT1-MMP基因可作为胃癌抗侵袭治疗的分子靶点.  相似文献   
965.
目的:探讨在乏氧状态下,丹参酮ⅡA对肝内胆管细胞癌(intrahepatic cholangiocarcinoma,ICC)自噬的调控,以及对侵袭能力的影响及其机制。方法:通过1%O_2培养建立肝内胆管细胞癌ICC-9810细胞乏氧状态,应用丹参酮ⅡA干预细胞后,通过划痕试验检测ICC-9810细胞迁移能力,趋化试验及侵袭试验检测细胞的趋化与侵袭能力;转染p GFP-LC3质粒后,应用荧光显微镜观察LC3融合蛋白及自噬小体在ICC-9810细胞中的表达情况,蛋白质印迹法检测ICC-9810细胞中的HIF-1α、自噬相关蛋白LC3Ⅱ/I和Beclin1表达差异。结果:在乏氧环境下,ICC-9810细胞运动能力增强(1.75±0.3)倍,趋化能力增加79.6%,侵袭力增强1.36倍,细胞自噬水平明显升高,丹参酮ⅡA干预后ICC-9810细胞自噬水平下调,HIF-1α、LC3Ⅱ/I和Beclin1蛋白表达水平分别降低3.9倍,2.4倍和1.1倍,侵袭能力下降4.7倍。结论:丹参酮ⅡA可以通过下调自噬,抑制肝内胆管癌细胞在乏氧条件下异常增高的侵袭力。  相似文献   
966.
Vascular development in endometriosis   总被引:8,自引:0,他引:8  
Endometriosis, defined as the presence of endometrial tissue outside the uterus, is an estrogen-dependent disease which causes pelvic pain and subfertility in women of reproductive age. The condition has a dramatic impact on the professional, social and marital life of sufferers. Direct and indirect evidence suggests that angiogenesis is required for the development and persistence of endometriosis. In this review the state-of-the-art with regard to our understanding of the role of angiogenesis in the ectopic implantation and survival of menstrual endometrial tissue will be discussed. Correspondence to: Patrick G. Groothuis, Research Institute GROW, Department of Obstetrics and Gynecology, Academisch Ziekenhuis Maastricht, Peter Debyelaan 25, 6229 HX Maastricht, The Netherlands. Tel:␣+31-43-3876625; Fax: +31-43-3876613; E-mail: patrick.groothuis@ path.unimaas.nl  相似文献   
967.
目的 探讨细胞粘附分子E 钙粘素 (E CD)和CD44变异体 (CD44V6)的表达与食管癌临床病理及预后的关系。方法 对 5 8例食管癌标本应用SP免疫组化染色法进行E CD、CD44V 6检测 ,并对其中 42例进行术后 3年随访。结果 E CD低表达和CD44V 6高表达与食管癌的浸润转移、复发和预后相关 (P <0 .0 5 )。E CD低阳性表达率与食管癌细胞分化程度相关 (P <0 .0 5 )。食管癌中E CD和CD44V6的表达无相关性 (P >0 .0 5 )。结论 E CD和CD44V 6在食管癌中的表达与食管癌的发生发展、侵袭转移和预后密切相关 ,E CD和CD44V6在食管癌中的表达无相关性 ,在食管癌的发生、发展、侵袭转移中是 2个独立的调节因子 ,可视为预测侵袭转移和估计预后的重要参考指标  相似文献   
968.
Plasma from a total of 57 patients with adult T-cell leukaemia (ATL) (acute ATL, 39 patients; lymphoma ATL, one patient; chronic ATL, 15 patients; smouldering ATL, two patients) and 20 healthy controls was analysed for the presence of type IV gelatinase activity with clinical features. A significant elevation of plasma matrix metalloproteinase-9 (MMP-9) was observed in some ATL patients, particularly in the patients with malignant cell infiltration. MMP-9 was found to be secreted into the conditioned medium from all ATL cell lines examined. Moreover, the corresponding mRNA was detectable both in all ATL cell lines examined and in the majority of primary acute ATL cells, indicating that ATL cells are capable of synthesizing and secreting MMP-9. We previously demonstrated that a high incidence of ATL cell infiltration was closely related to a high plasma level of vascular endothelial growth factor (VEGF) produced by ATL cells themselves. This present study showed that the presence of increased plasma MMP-9 was closely associated with elevated plasma VEGF in ATL patients. Furthermore, we showed that both increased plasma MMP-9 and VEGF were significantly related to high ATL cell infiltration. All these findings strongly suggest that MMP-9 and VEGF act co-operatively in the process of ATL cell invasion.  相似文献   
969.
For patients who have esophageal carcinoma with tracheal invasion surgery is usually not indicated because operative complications are considerable and the prognosis is poor. We experienced complete regression of a large esophageal carcinoma with tracheal stenosis due to tumor invasion without tracheo-esophageal fistula. Irradiation of 68 Gy was delivered to a long T field from the neck to the lower thoracic esophagus, and was combined with chemotherapy using cisplatin and 5-fluorouracil. The tumor decreased markedly in size and the tracheal stenosis resolved. The patient has survived for 4 years, although second primary early esophageal carcinoma and hypopharyngeal carcinoma were detected 2 years after his initial chemoradiotherapy. Although the prognosis of advanced esophageal carcinoma with invasion of other organs is usually poor, the effect of chemoradiotherapy can sometimes be dramatic and a good result can be achieved in such patients.  相似文献   
970.
The anatomy and topography of tissue surrounding the superior mesenteric artery were examined histopathologically, and the structure surrounding the superior mesenteric artery (SMA) was reconstructed with data from histologic examination and three-dimensional analyses. Specimens were obtained from three autopsy cases without abnormalities, two surgically resected cases of cancer of the pancreatic head, and one autopsy case of cancer of the pancreatic head. The endothelium or basal membrane of blood and lymph vessels were identified immunohistochemically, and the distribution of lymph nodes, blood vessels, lymph vessels, and collagen fibers was determined. The superior mesenteric plexus was found to be a relatively dense structure with a thickness of about 2 mm, composed of collagen fibers and connective tissue, which concentrically enveloped the small arteries, the superior mesenteric artery, nerve bundles, and capillaries. Lymph vessels larger than a few micrometers in diameter were often found outside of the plexus, and this plexus contained no lymph nodes in any sections. The three-dimensional study of the modes of spread along the superior mesenteric artery of pancreatic cancer revealed two types of spread: the tumor extends mainly by neural invasion, and the tumor extends mainly by lymph node metastases. These morphologic features suggest that lymphatic flow in the vicinity of the superior mesenteric artery passes primarily outside of the plexus, and complete excision of lymph nodes close to the superior mesenteric artery with preservation of the superior mesenteric plexus is feasible if there is no neural invasion into retropancreatic tissues.  相似文献   
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