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101.
102.
In this study the functional effectiveness of in vivo macrophage depletion using liposome-encapsulateddichloromethylene bisphosphonate (C12MBP) was examined in the chicken. The main target organs forsystemic liposome-encapsulated C12MBP treatment are the spleen and the liver. Intravenous treatment withC12MBP of B21/B21 chickens, genetically resistant to Marek's disease (MD), before challenge with the very virulent strain RB-lB, increased viral load in the blood and spleen after the first week and up to 6 weeks postinfection. In addition, C12MBP treatment dramatically increased tumour incidence and tumour load, especially in the spleens and livers of sick animals, but without affecting MD-specific mortality of B21/B21 cickens infected with RB-1B at 12 days of age. Nitric oxide (NO) is an important effector of the macrophage and has antiviral and antitumoural properties. NO has been shown to be one of the mechanisms triggered in resistance to Marek's disease. Intravenous treatment with Cl2MBP before infection with RB-1B induced a long-lasting decrease in numbers of macrophages and reduction in splenic inducible NO production associated with an absence of nitrate induction in the serum (up to 6 weeks pi). These results do not identify macrophage and NO production as major effector components in genetic resistance to Marek's disease, but underline their roles in limiting viraemia and tumour development in organs such as the spleen and the liver.  相似文献   
103.
患者男,67岁.主因咽异物感1个月,加重1周于2008年8月入院.患者入院1个月前无明显诱因出现咽异物感,偶有咽痛,无发热,无声音嘶哑及进食呛咳表现,未做正规检查,近1周以来咽异物感明显加重,偶有痰中带血表现,既往吸烟40年,15支/d.  相似文献   
104.
105.
背景:传统修复单椎体胸腰椎骨折常采用跨伤椎4钉固定,由于存在“平行四边形效应”及“悬挂效应”,容易发生内固定失败,复位高度及矫正角度丢失等并发症,而经伤椎椎弓根钉内固定,可避免或减少上述并发症发生。 目的:探讨经伤椎椎弓根螺钉置入内固定修复单椎体胸腰椎骨折的可行性。 方法:回顾性分析兰州大学第一医院骨科2013年1月至2014年6月收治的单节段胸腰椎骨折患者23例,损伤节段为T11-L2,平均年龄47.8岁,所有患者均在受伤后10 d内接受后路伤椎椎弓根螺钉和相邻上下椎椎弓根螺钉6枚螺钉内固定治疗,观察修复效果,包括术后短期并发症、椎体前缘高度比值及后凸Cobb角,以及脊髓神经功能损伤恢复情况。 d内接受后路伤椎椎弓根螺钉和相邻上下椎椎弓根螺钉6枚螺钉内固定治疗,观察修复效果,包括术后短期并发症、椎体前缘高度比值及后凸Cobb角,以及脊髓神经功能损伤恢复情况。 结果与结论:23例患者随访4-15个月,所有病例治疗后短期内(4-15个月)均未出现严重并发症,末次随访未出现钉棒断裂及内固定松动等情况。治疗后及末次随访所测得椎体前缘高度比值及后凸Cobb角均较治疗前明显改善,差异有显著性意义(P < 0.05),两项指标末次随访与治疗后相比稍有反弹,但差异无显著性意义(P > 0.05)。末次随访时大部分患者脊髓神经功能有所恢复。提示经伤椎椎弓根螺钉置入内固定修复单节段胸腰椎骨折,能够有效恢复伤椎高度及矫正后凸畸形,并能保持矫正效果,钉棒断裂发生率低,优势明显。 中国组织工程研究杂志出版内容重点:人工关节;骨植入物;脊柱;骨折;内固定;数字化骨科;组织工程  相似文献   
106.
Objective: Multi-drug resistance gene 1 (ABCB1) is closely related to bowel diseases. Therefore, our study was aimed to evaluate the correlation between ABCB1 polymorphisms (C1236T and C3435T) and ulcerative colitis (UC) susceptibility. Methods: A total of 61 UC patients and 64 healthy people participated in the study. Genotyping was conducted with the method of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). χ2 test was used to evaluate the association of ABCB1 gene polymorphisms (C1236T and C3435T) and UC susceptibility. Results: For ABCB1 C1236T polymorphism, the frequencies of CC genotype and C allele were found higher in the cases than those in the controls (CC: 36.1% vs. 20.3%; C: 58.2% vs. 41.4%), which indicated that the CC genotype and C allele might increase the risk for UC (OR = 3.39, 95% CI = 1.28-8.97; OR = 1.97, 95% CI = 1.19-3.26). However, there were no statistical differences in the genotype or allele distribution of ABCB1 C3435T between the case and control group. Conclusion: The CC genotype and C allele of ABCB1 C1236T polymorphisms are significantly associated with UC susceptibility, so we conclude that ABCB1 C1236T polymorphisms might serve as genetic-susceptibility factors for UC. While, no remarkable relationship is observed between ABCB1 C3435T polymorphisms and UC.  相似文献   
107.
The aim of this study was to examine β-arrestin1 expression in patients with lung adenocarcinoma (ADC) and explore the relationship of β-arrestin1 protein with clinicopathologic factors, vascular endothelial growth factor (VEGF) and prognosis. A total of 105 surgically resected lung adenocarcinoma patients were recruited for the study. The expression of β-arrestin1 and VEGF were determined by immunohistochemistry (IHC). The score measuring the β-arrestin1 and VEGF were calculated by combining the percentage of positive cells and the intensity of staining. Kaplan-Meier method and multivariable Cox proportional hazards regression analyses were used to examine the relationship between β-arrestin1 and survival. The results demonstrated that a notably higher level of β-arrestin1 expression was found in lung ADC tissues. We also found that an elevated nuclear Β-arrestin1 correlates with higher intratumoral VEGF (P = 0.007). β-arrestin 1 over-expression indicated a poor 5-year overall survival (P = 0.016), and the Cox regression model confirmed that β-arrestin1 over-expression were independent prognostic factor for tumor progression (P = 0.027) and unfavorable overall survival (P = 0.015). We conclude that β-arrestin1 had a high expression in ADC and β-arrestin1 may be a promising biomarker to identify individuals with poor prognosis for patients with ADC.  相似文献   
108.
Purpose: This study aimed to review the clinicopathological, histochemical, and prognostic features of Alpha-Fetoprotein (AFP) positive gastric cancer. Patients and methods: Six hundred and fifty one patients with gastric cancer who underwent gastrectomy between January 2009 and December 2012 at The First Hospital of Jilin University were enrolled in the study. Among them, 45 patients were identified as AFP positive gastric cancer. The clinicopathologic characteristics and prognosis of the AFP positive gastric cancer patients were analyzed. Results: Among the 45 AFP positive patients, serum levels of AFP were < 100 µg/L in nine patients. The histological classification of 45 patients was as follows: hepatoid type, 25 (55.6%) cases; fetal gastrointestinal type, 12 (26.7%) cases; yolk sac tumor type, 2 (4.4%) cases; and mixed type, 6 (13.3%) cases. Twenty nine (64.4%) cases were AFP positive by immunohistochemical analysis; we found no significant difference in AFP positivity and histologic type. However, the differences in the number of metastasis lymph nodes, the maximum tumor diameter, pathological stage, vascular invasion and liver metastasis between the AFP positive group and the negative group were significant. At the same T stage, the liver metastasis status of the AFP positive group was higher than that of the negative group. The AFP positive group had a much poorer prognosis than the negative group. Conclusion: AFP positive gastric cancer is associated with aggressive behavior and poorer prognosis compared to that of AFP negative gastric cancer.  相似文献   
109.

Introduction

Uncontrolled angiogenesis plays an essential role in the occurrence, metastasis and malignant progression of hepatocellular carcinoma (HCC). This study aimed to investigate the expression of adrenomedullin (ADM) in human HCC and its correlation with the expression of erythropoietin receptor (EPOR), microvessel density (MVD) and the tumor pathological characteristics.

Material and methods

Fresh tumor tissues were obtained from 30 HCC patients after hepatectomy. Ten cirrhotic and 10 normal liver tissues were included as controls. Expression of ADM and EPOR was determined by real-time PCR. The MVD was determined by counting the number of microvessels.

Results

The MVD and the mRNA levels of ADM and EPOR in cancer tissues were significantly higher than those in the non-cancer tissues (p < 0.05). Expression of ADM was significantly correlated with the MVD and EPOR (r = 0.68 and 0.74, p < 0.01). Adrenomedullin and EPOR mRNA levels in HCC tissues were correlated with capsule invasion, pathological differentiation and tumor metastasis (p < 0.05).

Conclusions

Our findings suggest that ADM and EPOR may serve as new regulatory factors involved in angiogenesis of HCC and represent novel targets for the treatment of HCC.  相似文献   
110.
背景:临床研究中进行腓骨重建修复下颌骨缺损的力学研究是不现实的,而有限元分析法为下颌骨缺损修复重建的生物力学研究提供了新的方法。目的:建立腓骨重建小钛板固定下颌骨体部缺损的三维有限元模型,对其进行生物力学分析。方法:建立下颌骨体部缺损腓骨重建三维模型及内固定模型,在前牙、健侧第一磨牙、健侧第二磨牙加载    100 N咬合力,观察下颌骨模型重建前后的最大应力值和最大位移值情况,前牙加载和后牙加载下重建模型钛板、钛钉孔周围骨质的应力情况,前牙加载和后牙加载下腓骨前后端的最大位移值情况。结果与结论:正常下颌骨的最大应力集中在髁突颈部。在重建模型中,最大应力集中在健侧髁突颈部,加载相同咬合力的情况下重建下颌骨的最大应力值均大于正常下颌骨的最大应力值,前牙加载最大应力值大于后牙加载。在每块钛板内侧的两钉孔之间应力值最大,下颌角部位的应力比较集中,加载侧近下颌骨缺损处前上方的第一颗钛钉为下颌骨残端钛钉的最大应力集中部位,近腓骨中段后下方钛钉为腓骨端钛钉的最大应力集中部位。下颌骨残端近缺损处以及腓骨中段上板处的钉孔周围皮质骨为最大应力集中部位,前牙加载时的最大应力大于后牙加载时的最大应力。腓骨在X轴上从上缘到下缘的位移值不断减少,在Y轴上从前下方及后端至中份的位移值逐渐减少,在Z轴上从前端到后端的位移值逐渐减少。腓骨前端的最大位移值在Z轴方向,后端的最大位移值在Y轴方向上,前牙加载时的最大位移值均较后牙加载时的最大位移值大。说明下颌角后上方钛板最易折断,应对其进行加固处理;钛钉尖端和颈部应力比较大,应选择双皮质钛钉;腓骨端和下颌骨残端钛钉和钛板的应力比较大,应重视其稳定性和固位性;前牙咬合时的应力大于后牙咬合时的应力,修复后应避免前牙咬合。 中国组织工程研究杂志出版内容重点:生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程  相似文献   
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