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1.
《Diagnostic Histopathology》2022,28(9):399-405
Temporal artery biopsy is recommended for diagnosis of suspected giant cell arteritis, a systemic vasculitis of older adults. There is currently no formal consensus for histological interpretation of the biopsies. Typical histological findings include a transmural lymphocytic infiltrate with a population of macrophages resulting in destruction of the internal elastic lamina. However, it is a patchy process and multiple tissue levels must be examined. It is important to be aware of various subtle features that may lead to a diagnosis of arteritis, and immunohistochemistry can be helpful in some cases. Some biopsies show unusual features that could raise a differential diagnosis of alternative vasculitides. When there is no evidence of arteritis in a specimen, there are often non-specific features seen in the context of age-related changes. All of these histological patterns require close clinicopathological correlation to ensure correct interpretation. 相似文献
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目的 观察体外人脐带间充质干细胞(human umbilical cord mesenchymal stem cells,hUCMSCs)能否由视网膜匀浆上清液诱导分化为神经样细胞及移植到视网膜光损伤大鼠玻璃体内后存活、迁移、整合及分化的情况。方法 无菌条件下采集健康足月剖宫产胎儿的正常脐带组织,经2.5 g·L-1胰蛋白酶和1 g·L-1胶原酶消化、贴壁培养获得hUCMSCs。将CM-Dil标记的hUCMSCs注入光损伤大鼠玻璃体内,观察眼内整合分化情况,对正常对照组、光损伤组、PBS治疗组和hUCMSCs治疗组大鼠视网膜外核层层数和厚度进行对比分析。结果 hUCMSCs培养48 h后贴壁生长,呈长梭形,14 d后可见细胞融合成片。光损伤后大鼠视网膜外核层结构紊乱、细胞层数减少,厚度变薄,与正常对照组[(40.73±1.32)μm]相比,hUCMSCs治疗组[(31.28±1.79)μm]与PBS治疗组[(17.21±1.02)μm]及光损伤组[(12.68±1.42)μm]的视网膜外核层厚度均变薄(均为P<0.05)。与光损伤组相比,PBS治疗组和hUCMSCs治疗组视网膜外核层层数显著增加。结论 HUCMSCs移植到光损伤大鼠玻璃体内后能存活、迁移及整合到受损伤视网膜,hUCMSCs玻璃体内移植可抑制光损伤大鼠光感受器的凋亡。 相似文献
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Jinrui Li Feng Gao Shanshan Ma Yanting Zhang Junni Zhang Fangxia Guan Minghao Yao 《Journal of tissue engineering and regenerative medicine》2020,14(9):1261-1271
Stem‐cell‐based therapy is a promising strategy to treat challenging neurological diseases, while its application is hindered primarily by the low viability and uncontrolled differentiation of stem cell. Hydrogel can be properly engineered to share similar characteristics with the target tissue, thus promoting cell viability and directing cell differentiation. In this study, we proposed a new dual‐enzymatically cross‐linked and injectable gelatin hydrogel for regulating survival, proliferation, and differentiation of human umbilical cord mesenchymal stem cells (hUC‐MSCs) in a three‐dimensional matrix. This injectable gelatin hydrogel was formed by oxidative coupling of gelatin–hydroxyphenyl acid conjugates catalyzed by hydrogen horseradish peroxidase (HRP) and choline oxidase (ChOx). Modulus and H2O2 release can be well controlled by ChOx activity. Results from calcein‐AM/PI staining and Ki67 immunofluorescence tests demonstrated that the survival and proliferation behavior of hUC‐MSCs were highly enhanced in HRP1UChOx0.25U hydrogel with lower modulus and less H2O2 release compared with other groups. Attractively, the expression of neuron‐specific markers β‐III tubulin, neurofilament light chain (NFL), and synapsin‐1 was significantly increased in HRP1UChOx0.25U hydrogel as well. Additionally, in vitro hemolysis test and in vivo HE staining data highlighted the good biocompatibility. Undoubtedly, this injectable gelatin hydrogel's ability to control hUC‐MSCs' fate holds enormous potentials in nervous disorders' therapy and nerve regeneration. 相似文献
4.
《Actas urologicas espa?olas》2020,44(9):623-629
BackgroundTransplantation of kidneys with vascular anatomical variants remains a challenge. Due to its varying success in regard to graft function after transplantation, these organs have been frequently discarded assuming in advance an unaffordable rate of vascular complications.Patients and methodsWe performed three kidney transplants using organs from deceased donors harboring vascular variants (multiple arteries and short veins), including an unsplittable horseshoe kidney. Different grafts harvested from the same donor aorta, common iliac artery, and inferior vena cava, were used to reconstruct the initial vascular configuration by creating single arterial and venous conduits aimed to simplify the vascular anastomoses in the recipient.ResultsNo post-operative complications were recorded. Warm ischemia times remained comparable to single artery renal allografts. No delayed graft function was noted in any case, and every patient regained normal renal function after transplantation.ConclusionsVascular reconstruction using arterial and venous grafts harvested from the same deceased donor may result a helpful tool to simplify vascular anastomoses during transplantation surgery, thus avoiding their discard in advance, minimizing perioperative complications, and enabling normal graft function rates in the long-term follow-up. The successful outcome obtained by using this approach would help to expand the donor criteria for the inclusion of organs containing vascular anatomical variants. 相似文献
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目的优化1,8-桉叶油素(1,8-cineole,1,8-Cin)自微乳给药系统(1,8-cineole self-microemulsion drug delivery system,1,8-Cin-SMEDDS)处方,对其进行表征并进行细胞摄取考察。方法通过绘制伪三元相图,确定1,8-Cin-SMEDDS有效自乳化区域,进行初步处方筛选。以粒径和载药量为指标,采用星点设计-效应面法对1,8-Cin-SMEDDS处方进行优化并验证。荧光显微镜观察高糖损伤的人脐静脉内皮细胞(HUVEC)对1,8-Cin-SMEDDS的摄取情况。结果 1,8-Cin-SMEDDS的最佳处方是大豆油(7.5%)与1,8-Cin(22.5%)为混合油相,HS15(56%)为乳化剂,乙醇(14%)为助乳化剂,滴加纯水至8m L得半透明略带蓝色乳光液体。透射电镜观察其外观呈球形液滴,激光粒度Zeta电位测定仪测得平均粒径为(131.68±1.44)nm,Zeta电位为(-10.03±1.63)m V;HPLC法测得包封率为(99.890±0.012)%,载药量为(224.750±0.028)mg/g。HUVEC细胞摄取实验结果表明,细胞对1,8-Cin-SMEDDS的摄取高于游离1,8-Cin。结论 1,8-Cin-SMEDDS制备方法简便,重复性好,所得1,8-Cin-SMEDDS外观良好,包封率高,理化性质稳定,且能促进细胞摄取。 相似文献
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《药学学报(英文版)》2020,10(8):1453-1475
Angiokinases, such as vascular endothelial-, fibroblast- and platelet-derived growth factor receptors (VEGFRs, FGFRs and PDGFRs) play crucial roles in tumor angiogenesis. Anti-angiogenesis therapy using multi-angiokinase inhibitor has achieved great success in recent years. In this study, we presented the design, synthesis, target identification, molecular mechanism, pharmacodynamics (PD) and pharmacokinetics (PK) research of a novel triple-angiokinase inhibitor WXFL-152. WXFL-152, identified from a series of 4-oxyquinoline derivatives based on a structure–activity relationship study, inhibited the proliferation of vascular endothelial cells (ECs) and pericytes by blocking the angiokinase signals VEGF/VEGFR2, FGF/FGFRs and PDGF/PDGFRβ simultaneously in vitro. Significant anticancer effects of WXFL-152 were confirmed in multiple preclinical tumor xenograft models, including a patient-derived tumor xenograft (PDX) model. Pharmacokinetic studies of WXFL-152 demonstrated high favourable bioavailability with single-dose and continuous multi-dose by oral administration in rats and beagles. In conclusion, WXFL-152, which is currently in phase Ib clinical trials, is a novel and effective triple-angiokinase inhibitor with clear PD and PK in tumor therapy. 相似文献
10.
目的探讨脑源性微囊泡(BDMVs)对脐静脉内皮细胞骨架的影响。方法体外制备BDMVs,并予透射电镜观察及粒径检测。将PKH26荧光染料标记的BDMVs与脐静脉内皮细胞共培养0.5 h、1 h、2 h后,应用流式细胞术检测不同时间点的脐静脉内皮细胞吞噬BDMVs情况。将体外常规培养的脐静脉内皮细胞分为对照组、BDMVs组(加入终浓度1.5×10^7/mL的BDMVs处理细胞)及尼莫地平组[予2μg尼莫地平(0.2 mg/mL)预处理10 min后加入终浓度1.5×10^7/mL的BDMVs处理细胞],应用激光共聚焦显微镜观察罗丹明标记鬼笔环肽染色后各组脐静脉内皮细胞中纤维型肌动蛋白的荧光强度及应力纤维数目。结果透射电镜下可见体外制备的BDMVs具有完整的膜结构,粒径范围为100~1000 nm。流式细胞术检测显示,吞噬BDMVs的脐静脉内皮细胞比例随培养时间的延长呈时间依赖性升高(0.5 h:22.7%±1.2%;1 h:52.3%±1.3%;2 h:71.6%±1.9%),各时间点间两两比较差异均有统计学意义(P<0.05)。激光共聚焦显微镜观察显示,与对照组相比,BDMVs组中纤维型肌动蛋白的荧光强度明显升高且应力纤维数目明显增多增粗;而与BDMVs组相比,尼莫地平组中纤维型肌动蛋白的荧光强度明显降低且应力纤维数目明显减少变细。结论脐静脉内皮细胞吞噬BDMVs的作用随时间延长而增强,且吞噬BDMVs后可导致细胞骨架重构,而尼莫地平可部分阻断该作用。 相似文献