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81.
A. S. Lopatin 《European archives of oto-rhino-laryngology》1996,253(4-5):309-312
Biomechanical techniques can be used for correcting C-shaped or S-shaped nasal septum cartilage deformities. These include mucoperichondrium elevation on the concave side, trimming cartilage to its necessary size, incisions to release cartilaginous bends and strip resections. Resection and reimplantation of cartilage are preferable when correcting a difficult post-traumatic septum. While biomechanical principles are applicable to nasal septum surgery, further clinical studies must be devised to provide proper correction of the nasal septum with minimal sacrifice of cartilage. 相似文献
82.
Summary Extracellular matrix vesicles from fracture callus cartilage were isolated by differential centrifugation and resolved by equilibrium centrifugation on a discontinuous sucrose gradient into two bands. The phosphohydrolytic activity towards p-nitrophenyl phosphate, tetrasodium pyrophosphate and adenosine triphosphate was distributed similarly after differential and equilibrium centrifugation suggesting the association of this activity with the matrix vesicles. The two bands isolated by equilibrium centrifugation of the partially purified vesicular preparation demonstrated high levels of alkaline phosphatase activity. Observed with an electron microscope, the 1.07–1.14 g/cm3 band from the gradient was enriched in electron luscent matrix vesicles while the 1.27 g/cm3 band contained electron dense matrix vesicles. Enzymatic analysis of the 1.27 g/cm3 band indicated a slight contamination due to the presence of mitochondria and lysosomes while the 1.07–1.14 g/cm3 band gave no enzymatic indication of subcellular contamination. A phosphohydrolytic enzyme active towards p-nitrophenyl phosphate, tetrasodium pyrophosphate and adenosine triphosphate was purified from the 1.07–1.14 g/cm3 fraction by DEAE-cellulose column chromatography. Electron micrographs of callus cartilage sections demonstrated densification of the plasma membrane and matrix vesicles following substrate incubation with-glycerophosphate or tetrasodium pyrophosphate. The histochemical and biochemical data indicate that a phosphatase, with multiple substrate specificity, is a component of fracture callus cartilage matrix vesicles. 相似文献
83.
The cosmetic deformities following enucleation are often unavoidable. Loss of orbital volume and atrophy of orbital fat create significant enophthalmos. The literature is filled with numerous procedures that add to the orbital volume of the anophthalmic socket. An outline of three procedures to the upper eyelid to camouflage an enophthalmic appearance are presented. These can be used alone or in conjunction with an "orbital volume increasing" procedure. Two procedures can be used in an office setting to alleviate small deformities; 19 patients have been treated in this manner with a follow-up period of up to 26 months. 相似文献
84.
85.
骨质疏松性骨折骨痂软骨细胞CD44、FN表达的实验研究 总被引:1,自引:0,他引:1
目的:探讨骨质疏松性骨折愈合过程中胞内信号因子CD44及其配体FN在骨痂软骨细胞的表达情况。方法:建立28只SD大鼠骨质疏松性股骨骨折愈合模型作为实验组以及28只二期股骨骨折愈合模型作为对照组,分别于骨折后的d10、d20、d30、d40取材,对骨痂进行HE染色及CD44、FN免疫组化染色。结果:在骨痂组织中CD44和FN的表达及分布在时空上有一致性。在实验组中,随着骨折愈合进程的发展,软骨细胞CD44与FN的表达逐渐减少,而对照组中,CD44与FN共同表达于骨折愈合各阶段的各区软骨细胞中。结论:大鼠骨质疏松性骨折愈合过程中骨痂软骨细胞CD44、FN的表达明显弱于正常二期骨折愈合过程中的表达,提示:CD44、FN在软骨细胞中表达的明显减少可能是造成骨质疏松性骨折骨痂软骨组织向骨组织演变缓慢的原因之一。 相似文献
86.
碱性成纤维细胞生长因子对兔关节软骨全层缺损的修复作用 总被引:1,自引:0,他引:1
目的:利用注射型活性材料碱性成纤维细胞生长因子(bFGF)修复兔关节软骨缺损,观察其治疗效果。方法:实验尝试在兔的膝关节软骨缺损区应用碱性成纤维细胞生长因子,分别于10周,14周,18周处死,观察大体和形态学特征,组织学评分。结果:A组于10、14周时,软骨缺损被白色半透明坚硬组织平滑修复,富有光泽,与正常软骨边界清楚,18周时修复组织与正常软骨边界模糊,质地坚硬,表面平滑光润。对照组于10、14、18周时均未见软骨修复。组织学评分A组明显优于对照组。结论:碱性成纤维细胞生长因子可以有效修复兔关节软骨的缺损,为组织工程化软骨的临床应用提供理论基础。 相似文献
87.
由创伤或其他病因引起的关节软骨病变通常难以自愈,且目前临床上的治疗方法疗效欠佳。脂肪干细胞 (adipose derived stem cells,ADSCs)是一种来自脂肪组织、具有多向分化潜能的干细胞,基于ADSCs成软骨分化能力的 组织工程学疗法为关节软骨缺损的修复再生提供了新的思路。体外诱导ADSCs分化成软骨的方法主要是采用生长因 子和支架材料模拟体内微环境,进而促进ADSCs向软骨细胞分化,其相关应用已取得初步成功。 相似文献
88.
《Inmunología》2014,33(4):121-127
Rheumatoid arthritis is an autoimmune disease characterized by polyarticular inflammation, swelling and inflammation that affects more than 1% of the world population. The pathobiology of rheumatoid arthritis involves several cell populations as T lymphocytes, B, macrófagosy fibroblasts, and a complex proinflammatory cytokines interactions. Conventional and biologic therapies do not always work or produce only a partial improvement. Immunological tolerance is a mechanism by which the immune system prevents autoreactivity. The aim of this pilot study was to evaluate the efficacy of peptides from an from articular cartilage hydrolysate extracted of tarsus (HCA) for the treatment of rheumatoid arthritis in a model of rheumatoid arthritis (AAE) in rabbits. AAE animals showed inflammation and pain within de first month of the primary immunization that was reversed in the AAE + HCA group. The control group showed a normal unnaffected synovial tissue. The AAE group revealed an inflamatory process whith synovial hyperplasia, filtering in lymphocytes and vascular proliferation. The treated group decreased significantly inflammation, lymphocyte proliferation and angiogenesis. Arthritic rabbits increased the levels in flammatory markers as nitric oxide, interferon gamma (INF-ɣ) and tumor necrosis factor alpha (TNF-α) compared to control and significantly reduced levels of interleukin 4 (IL-4). The treatment showed a significant reduction of nitricoxide, IFN-gamma and TNF-alpha and an increase in IL-4. This work suggests that this therapy may be useful in the clinical aspect and the biochemical and immune parameters. Future studies with larger numbers of animals and other laboratory parameters may provide additional evidence in this regard. 相似文献
89.
《Expert Review of Clinical Immunology》2013,9(2):173-191
This review focuses on the role of glycosylation during the development of joint inflammation and degeneration. Although glycoproteins and glycan-binding proteins have essential functions in bone and cartilage, and in the inflammatory process, their exact roles are still uncertain due to the vast complexity of carbohydrate structures. Glycosylated epitopes have been shown to play a role in the induction of arthritis in animal models. Currently available drugs are aimed at the protection of cartilage and bone structures but new developments in this area should take into account the tight and specific interactions between bone and cartilage. It is anticipated that new agents will help to remodel damaged joints, based on knowledge of cartilage and bone turnover and on the exact role of glycosylated molecules and cell surface receptor glycoproteins in these processes. Highly sensitive imaging techniques and well-characterized In vivo models will accelerate this development. 相似文献
90.
《Connective tissue research》2013,54(4):241-264
Soluble substances in the bovine nuchal ligament were removed by preliminary extractions with a buffer and dilute alkali solution. The insoluble residue was then extracted with 6 M guanidine HCl and with 6 M guanidine HCl containing a reducing agent (20 mM dithiothreitol) successively. Each of the two extracts contained a glycoprotein; that in the first extract was designated Glycoprotein A and that in the second Glycoprotein B. They were purified by ion-exchange chromatography and gel filtration till essentially homogeneous. Both proteins had similar molecular weights of 35,000 in SDS-polyacrylamide gel electrophoresis and by gel filtration, and their chemical compositions resembled each other closely. It is suggested that Glycoprotein B was present in the native state as a disulfide-bonded, aggregated form of Glycoprotein A. The compounds also showed similarity with the microfibrillar glycoprotein(s) previously reported in bovine nuchal ligament extracts. 相似文献