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981.
Objective To assess the value of detecting sympathetic skin response (SSR) in the diagnosis of autonomic dysfunction in patients with Parkinson disease (PD). Methods SSR measurement was performed in 47 PD patients and 20 healthy control subjects and the results were compared. The SSR was also comparatively analyzed between patients with and those without autonomic dysfimction. Results Compared with the healthy controls, the PD patients showed significantly lowered mean amplitude (2.56±1.47 vs 1.87±0.26, P<0.05) and prolonged latency (1.42±0.29 vs 1.55± 0.18, P<0.05) of the SSR in the upper limbs, with also lowered mean amplitude (0.76±0.39 vs 0.49±0.21, P<0.05) and prolonged latency (2.04±0.27 vs 2.13±0.16, P<0.05) in the lower limbs. Compared with the PD patients without autonomic dysfunction, those having autonomic dysfunction showed significantly lowered mean amplitude (1.89±0.33 vs 1.75±0.21, P<0.05) and prolonged latency (1.53±0.15 vs 1.56±0.17, P<0.05) of SSR in the upper limbs and lowered mean amplitude (0.51±0.17 vs 0.46±0.20,P<0.05) and prolonged latency (2.08±0.24 vs 2.17±0.18, P<0.05) in the lower limbs. Conclusion The results of SSR measurements are consistent with the clinical manifestations of the PD patients. SSR can be of value in the diagnosis of autonomic nerve dysfunction in PD. 相似文献
982.
目的研究雷帕霉素对肾缺血再灌注(IR)后不同时期肾小管上皮细胞凋亡及增殖、修复的影响。方法体质量为25~30 g BALB/c小鼠45只随机分为手术对照组、IR对照组和雷帕霉素组。建立阻断小鼠左侧肾蒂30 min后切除右侧肾模型。雷帕霉素组术前及术后每日给予0.5 mL雷帕霉素和生理盐水混悬液(1 mg∶10 mL)灌胃,IR对照组给予等量生理盐水灌胃。术后1、3和7 d每组各处死5只小鼠取全血及肾组织,检测血清肌酐水平,HE染色评价组织病理学改变。采用脱氧核糖核苷酸末端转移酶介导的缺口末端标记法检测肾小管上皮细胞凋亡,通过免疫组织化学检测肾小管上皮细胞增殖细胞核抗原以比较组间肾小管上皮细胞增殖修复差异。结果雷帕霉素组术后1 d肾功能好于IR对照组(P〈0.05),但在7 d时却较IR对照组差(P〈0.05)。IR对照组和雷帕霉素组术后3个时期的肾组织病理学改变均较手术对照组严重(P〈0.05),但前两组间损伤病理学评分均无明显差异(P〉0.05)。术后1 d和3 d时,雷帕霉素组凋亡细胞数明显少于IR对照组(P〈0.05)。术后1、3和7 d雷帕霉素组肾小管上皮细胞增殖细胞核抗原表达水平均显著低于IR对照组(P〈0.05)。结论肾缺血再灌注损伤早期以肾小管上皮细胞凋亡为主,后以细胞增殖修复为主。雷帕霉素因具有抗凋亡和抗增殖的双重作用,可以减轻缺血再灌注对肾功能损伤,但却不利于以后的组织修复。 相似文献
983.
目的 建立2型糖尿病大鼠动物模型,探讨晚期糖基化终末产物及其受体在实验性2型糖尿病大鼠种植体骨整合过程中的变化及表达.方法 45只3个月龄SD健康雄性大鼠,将大鼠随机分为糖尿病模型组25只和正常对照组20只.首先建立2型糖尿病大鼠模型,建模成功后将模型大鼠随机分为DM组和DM种植组,每组10只.将20只正常组大鼠随机分为正常对照组和正常种植组,每组10只.分别于正常种植组和DM种植组的胫骨近骺端植入纯钛种植体,植入10周后于下腔静脉采血,保存所采集标本,用RF-5301PC型荧光分光光度计测定血清中AGEs含量的变化.硬组织标本采用不带种植体脱钙切片,以正常组为对照,HE染色后用免疫组织化学方法检测种植体周围RAGE的表达.结果 10周后,DM种植组和DM组与正常对照组和正常种植组相比,血清中AGEs的变化差异有统计学意义(P <0.05),正常种植组和DM种植组与正常对照组的种植体周围骨组织RAGE表达比较,差异均有统计学意义(P <0.05);DM种植组与DM组比较,差异亦有统计学意义(P <0.05).结论 种植体骨组织愈合过程中AGEs和RAGE相互作用是影响2型糖尿病种植体骨结合的机制之一. 相似文献
984.
Zheng‐Jian Xu Lian‐Yi Chen Cheng Zhong Yan‐Bin Tan Rong‐Xin He 《Journal of orthopaedic research》2011,29(10):1491-1495
We compared the mechanical properties of morselized cancellous bone grafts of two sizes: 7–10 mm bone and small slurry bone (about 2 mm). The in vitro test was designed to simulate the hammer and impactor system for impaction bone grafting used in hip arthroplasty clinical practice. The 7–10 mm bone grafts showed higher height, elastic modulus, and massive extrusion strength than those of the small slurry bone grafts. No difference was found in yield strength. The bone mineral density of the 7–10 mm grafts continued to increase during impaction and became higher than that of the small slurry bone grafts after 10 impactions. Our results demonstrated that the small slurry bone grafts exhibit worse mechanical properties as compared with the 7–10 mm bone grafts, which implies that the use of this material in reconstruction of a bone defect in the acetabulum should be limited. © 2011 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29: 1491–1495, 2011 相似文献
985.
Shun Cui Fei Xiong Yan Hong Ji‐Ung Jung Xing‐Sheng Li Jian‐Zhong Liu Riqiang Yan Lin Mei Xu Feng Wen‐Cheng Xiong 《Journal of bone and mineral research》2011,26(5):1084-1098
Alzheimer's disease (AD), one of the most dreaded neurodegenerative disorders, is characterized by cortical and cerebrovascular amyloid β peptide (Aβ) deposits, neurofibrillary tangles, chronic inflammation, and neuronal loss. Increased bone fracture rates and reduced bone density are commonly observed in patients with AD, suggesting one or more common denominators between both disorders. However, very few studies are available that have addressed this issue. Here, we present evidence for a function of amyloid precursor protein (APP) and Aβ in regulating osteoclast (OC) differentiation in vitro and in vivo. Tg2576 mice, which express the Swedish mutation of APP (APPswe) under the control of a prion promoter, 1 exhibit biphasic effects on OC activation, with an increase of OCs in younger mice (< 4 months old), but a decrease in older Tg2576 mice (> 4 months old). The increase of OCs in young Tg2576 mice appears to be mediated by Aβ oligomers and receptor for advanced glycation end products (RAGE) expression in bone marrow macrophages (BMMs). However, the decrease of OC formation and activity in older Tg2576 mice may be due to the increase of soluble rage (sRAGE) in aged Tg2576 mice, an inhibitor of RANKL‐induced osteoclastogenesis. These results suggest an unexpected function of APPswe/Aβ, reveal a mechanism underlying altered bone remodeling in AD patients, and implicate APP/Aβ and RAGE as common denominators for both AD and osteoporosis. © 2011 American Society for Bone and Mineral Research. 相似文献
986.
987.
骨肉瘤边界包含着丰富的肿瘤病变的特征信息,对疾病的分类、临床治疗方案设定、疾病预后具有重要意义。分子生物学和基因组学研究的不断深入,为骨肉瘤的分子边界研究提供了理论基础,并且为检测分子边界相关标志物提供了必要的技术手段.一些新的分子标记物也随之被提出并研究。本文就目前相关领域的骨肉瘤分子边界相关标记物进行综述。 相似文献
988.
989.
Staphylococcus aureus is an uncommon causative agent of monomicrobial necrotizing fasciitis, but we have noted several cases over the years. The patients treated for necrotizing fasciitis between January 1998 and December 2008 in our institution were identified, and their medical records were reviewed. Of 105 necrotizing fasciitis cases during the study period, 18 were caused by monomicrobial S. aureus infection (17%). The median age was 62 years (range, 12-81 years). Among this cohort, 10 patients had coexisting medical conditions or risk factors, including diabetes and hypertension. Lower limbs and upper limbs are the most commonly involved sites. Among the bacterial isolates from these cases, 8 were methicillin-sensitive S. aureus (MSSA) and 10 were methicillin-resistant S. aureus (MRSA). One patient died in the MSSA group, and 5 patients died in the MRSA group. The mortality rate and other clinical characteristics were not significantly different between the 2 groups. However, all MRSA necrotizing fasciitis developed after the year 2000, and it was significantly different from MSSA necrotizing fasciitis that predominantly took place before the year 2000. In conclusion, S. aureus is an important pathogen of monomicrobial necrotizing fasciitis, and MRSA has emerged as the predominant causative agent in recent years. Therefore, MRSA-directed antibiotic therapy should be considered when treating patients suspected with necrotizing fasciitis in endemic areas. 相似文献
990.
Li HY Liao CY Lee KH Chang HC Chen YJ Chao KC Chang SP Cheng HY Chang CM Chang YL Hung SC Sung YJ Chiou SH 《Cell transplantation》2011,20(6):893-907
Embryonic stem (ES) cell transplantation represents a potential means for the treatment of degenerative diseases and injuries. As appropriate distribution of transplanted ES cells in the host tissue is critical for successful transplantation, the exploration of efficient strategies to enhance ES cell migration is warranted. In this study we investigated ES cell migration under the influence of various extracellular matrix (ECM) proteins, which have been shown to stimulate cell migration in various cell models with unclear effects on ES cells. Using two mouse ES (mES) cell lines, ESC 26GJ9012-8-2 and ES-D3 GL, to generate embryoid bodies (EBs), we examined the migration of differentiating cells from EBs that were delivered onto culture surfaces coated with or without collagen I, collagen IV, Matrigel, fibronectin, and laminin. Among these ECM proteins, collagen IV exhibited maximal migration enhancing effect. mES cells expressed α2 and β1 integrin subunits and the migration enhancing effect of collagen IV was prevented by RGD peptides as well as antibodies against α2 and β1 integrins, indicating that the enhancing effect of collagen IV on cell migration was mediated by α2β1 integrin. Furthermore, staining of actin cytoskeleton that links to integrins revealed well-developed stress fibers and long filopodia in mES cells cultured on collagen IV, and the actin-disrupting cytochalasin D abolished the collagen IV-enhanced cell migration. In addition, pretreatment of undifferentiated or differentiated mES cells with collagen IV resulted in improved engraftment and growth after transplantation into the subcutaneous tissue of nude mice. Finally, collagen IV pretreatment of osteogenically differentiated mES cells increased osteogenic differentiation-like tissue and decreased undifferentiation-like tissue in the grafts grown after transplantation. Our results demonstrated that collagen IV significantly enhanced the migration of differentiating ES cells through α2β1 integrin-mediated actin remodeling and could promote ES cell transplantation efficiency, which may be imperative to stem cell therapy. 相似文献