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81.
82.
踝关节慢性前外侧不稳的手术治疗 总被引:1,自引:0,他引:1
目的: 探讨治疗踝关节慢性前外侧不稳定 (踝关节外侧不稳定合并距下关节不稳定) 的合理而有效的手术方式。方法: 自 1999 ~2003年, 应用Chrisman Snook术式, 以腓骨短肌腱前半部分重建距腓前韧带、跟腓韧带和距跟外侧韧带,治疗踝关节慢性前外侧不稳 8例患者,共 13例关节。结果: 术后随诊 6个月~5年, 平均 19个月。术后所有踝关节均达到功能稳定, 关节活动度基本恢复正常, 没有复发性踝关节不稳发生。以Good评级标准作为疗效评价, 10例关节 (77% ) 为优, 2例关节 (15% ) 为良, 1例关节为中 (7% ), 优良率达 92%。结论: Chrisman Snook术式重建了距腓前韧带、跟腓韧带和距跟外侧韧带, 有效地矫正了踝关节外侧不稳定和距下关节不稳定, 是治疗踝关节慢性前外侧严重不稳定的合理而有效的治疗方法。 相似文献
83.
人工全髋关节置换术中偏心距重建对髋关节功能的影响 总被引:2,自引:0,他引:2
目的比较标准股骨假体行人工全髋关节置换术中股骨假体颈长和股骨距保留对偏心距重建的作用,并分析偏心距重建对软组织平衡的影响。方法68例(71髋)行初次全髋关节置换术并获得随访。术中确定双下肢等长、髋关节稳定及周围软组织紧张度适中。术后采用Harris评分评估手术结果,Cybex-6000等速测定患髋外展肌力,通过手术记录和X线片测量获得偏心距、股骨距、假体颈长、外展肌力臂,用SPSS11.5统计学软件包对数据进行分析。结果假体颈长对偏心距的影响较股骨距大(P<0.01),并与偏心距呈正相关关系(r=0.642,P<0.001),但两者对于Harris评分影响的差异无统计学意义(P〉0.05)。股骨头坏死患者术后的偏心距较髋关节骨关节炎患者(P<0.01)和股骨颈骨折患者小(P<0.01)。颈于角与偏心距外展肌力臂比呈正相关关系(r=0.25,火0.05)。偏心距重建较好的髋关节术后外展肌力较偏心距重建不足者优(P<0.05),且两者呈相关关系(r=0.29,P<0.05)。结论偏心距的重建在全髋关节置换术软组织平衡中主要起到增强术后外展肌力的作用。采用标准股骨假体重建术后股骨偏心距,股骨假体颈长对人工全髋关节置换术后偏心距的重建作用大于股骨距的保留,在诸多影响因素中起到关键作用。 相似文献
84.
寰椎后弓侧块螺钉进钉角度的影像学研究及临床应用 总被引:3,自引:0,他引:3
目的探讨寰椎后弓侧块螺钉置钉安全角度及临床应用价值。方法对30名寰枢椎形态正常者行颈椎侧位X线摄片和寰枢椎轴位CT扫描,在影像学图像上对寰椎后弓最小高度、矢状面最大进钉倾斜角、最大进钉内倾角等参数进行测量。应用影像学观测的进钉角度对21例上颈椎不稳定患者行后路寰椎后弓侧块螺钉固定,术中观察后弓侧块螺钉置入后对周围重要组织结构的影响,术后观察有无神经症状加重。其中13例行手术前后CT检查,并测量螺钉置入前后的相关参数,评估置钉的安全性。结果(1)寰椎后弓侧块矢状面进钉倾斜角最大头倾10°、最大尾倾6°,最大倾斜角随寰椎后弓最小高度的增加有增大的趋势;(2)当进钉点由内侧改为外侧时,置钉内倾角需作0°~30°的相应调整;(3)手术实际进钉角度与术前预测有一定的差异,但均在预测范围内;(4)临床病例均置钉成功,影像学显示在常用的进钉区域内置钉无螺钉伤及椎动脉、脊髓等周围组织的现象。结论寰椎后弓侧块置钉在矢状面和轴平面上均有一定的安全角度范围,依据此范围置钉可增加寰椎后弓侧块螺钉固定的安全性和可操作性。 相似文献
85.
Petri S. Mattila Jan Schugk Hongyan Wu Olli Mkel 《European journal of immunology》1995,25(9):2578-2582
During the initial stages of B lymphocyte differentiation heavy chain variable (VH), diversity (DH) and joining (JH) gene segments recombine to form a functional heavy chain variable region (VDJ) gene. Evidence for genetic polymorphism of the human JH gene segments has been obtained from mature rearranged VDJ sequences. We conducted an analysis of the published rearranged JH gene sequences and found that the JH alleles present in the two published germ-line JH region sequences were rare (approx. 2%) in the rearranged sequences. As an attempt to explain this discrepancy a 2.5-kb strech of DNA containing all the six heavy chain JH region genes and the most 3' DH gene segment, DHQ52, was amplified by the polymerase chain reaction from 39 individuals and analyzed for restriction fragment length polymorphism. Five new JH region haplotypes were found and sequenced. These new haplotypes contained the coding segment alleles that were frequent in antibody genes. Surprisingly, a high number of interallelic differencies in the non-coding sequence was found between the new and the two previously published haplotypes implying that the haplotypes had been separated early in evolution. In this respect the JH locus resembles HLA loci. 相似文献
86.
肾发育不良和肾发育不全(RAH)是先天性肾脏与尿路畸形(CAKUT)的主要表现之一,是导致儿童慢性肾脏病的重要原因。遗传因素与发病密切相关,随着全基因检测技术的发展,越来越多与RAH相关的基因突变被报道,GREB1L基因突变已被证实可导致RAH。本研究报道了1例后天性单侧肾萎缩GREB1L基因c.4688A>G杂合突变患儿,并复习相关文献。该患儿基因突变源自母亲,该变异为罕见变异,并且具有不完全外显特性,多种蛋白质危害预测软件预测该突变为有害变异。本文发现了新的GREB1L基因突变位点,可能拓展了与RAH相关的基因突变谱和临床谱。 相似文献
87.
目的 探讨中国江苏地区汉族人群肿瘤坏死因子 β遗传多态性分布。方法 收集江苏地区 16 8名无血缘关系健康个体的静脉血提取DNA ,应用聚合酶链反应限制性片段长度多态性 (PCR -RFLP) ,对TNFβ基因多态性进行分析。结果 TNFβ检测到三个等位基因 ,其基因型频率分别为TNFβ 1/ 1=2 1 4 % ,TNFβ 1/ 2 =4 7% ,TNFβ 2 / 2 =31 5 % ,基因型分布符合Hardy-Weinberg定律。统计分析显示 :江苏地区汉族人群TNFβ等位基因频率分布与欧美白种人均有显著性差异(P <0 0 5 )。结论 TNFβ等位基因频率分布具有种族差异 相似文献
88.
《The Knee》2022
BackgroundPatellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography.PurposeTo report the postoperative outcomes of patients age 21 and younger treated with particulated juvenile allograft cartilage (PJAC) for full-thickness cartilaginous defects of the patellofemoral joint. The primary aim was to report surgical outcomes and complication rates, as well as return to sport activity. A secondary aim was to provide objective scores of defect restoration by magnetic resonance imaging (MRI) assessment.MethodsA retrospective review of all PJAC cases conducted between 2012 and 2019 at a single tertiary care urban musculoskeletal institution was conducted. Patients 21 years old or younger with minimum clinical follow up of 1 year and postoperative MRI at a minimum of 6 months were included. Cartilage restoration by MRI was independently assessed using the International Cartilage Repair Society’s (ICRS) standardized system.ResultsThirty four patients, 36 knees, were included, with mean age 16.1 ± 3.1 years old. Return to sport rate among patients who participated in a sport preoperatively was 100%. On independent MRI assessment, two thirds of defects achieved an overall grade of normal or nearly normal, while 28 patients (78%) had majority defect fill. Primary graft failure occurred in two cases and one patient experienced a surgical complication.ConclusionRestoration of patellofemoral chondral defects in young patients with particulated juvenile allograft results in satisfactory short-term outcomes and postoperative MRI appearance, along with high rates of return to sport and low rate of complications and graft failure.What is known about the subject: Patellofemoral joint cartilage defects are difficult to treat due to their unique thickness and topography. Several cartilage restoration techniques are available, but these rarely achieve the same mechanical properties as native hyaline cartilage. PJAC is a cell-based technique that has demonstrated promise since its introduction in 2007.What this study adds to existing knowledge: This series of patients adds the largest single cohort of pediatric and adolescent patients who receive PJAC for defects of the patellofemoral joint. Surgeons treating patients in this age group should be aware of every technique, and their respective outcomes. 相似文献
89.
Grisk O Lother U Gabriëls G Rettig R 《Pflügers Archiv : European journal of physiology》2005,449(4):364-371
Renal transplantation experiments have shown that the kidney contributes to chronic sympathectomy-induced arterial pressure reduction in spontaneously hypertensive rats (SHR). The underlying mechanisms are currently unclear but may include alterations in the function of small renal arteries. Neonatal SHR were sympathectomized by intraperitoneal guanethidine injections and removal of adrenal medullary tissue. Controls were sham- or hydralazine-treated. At 12 weeks of age, distal interlobar artery segments were investigated using small-vessel wire myography. Vessels from sympathectomized animals showed increased sensitivity to noradrenaline (NE). Vasopressin- and endothelin-1-induced vasoconstriction was similar in all groups (as reflected by the pD2, i.e. –logEC50, where EC50 is the molar concentration of agonist eliciting a half-maximal response). Maximum vasopressin-induced tension was similar in all groups while endothelin-1-induced maximum tension was significantly higher in sympathectomized than in sham-treated SHR. The sensitivity of NE-induced vasoconstriction to extracellular Ca2+ did not differ between groups while sensitivity to L-type Ca2+ channel activation was significantly higher in both sympathectomized and hydralazine-treated animals than in sham-treated animals. Endothelium-dependent and independent vasodilation were similar in all groups. Sequential blockade of NO-synthase and cyclooxygenase had similar effects in all groups. In conclusion, neonatal sympathectomy does not induce any changes in the function of isolated proximal renal resistance arteries from SHR that could explain the blood pressure lowering effect of a kidney graft from sympathectomized SHR. 相似文献
90.
Animal models in the investigation of anorexia 总被引:3,自引:0,他引:3
Anorexia nervosa (AN) is an eating disorder of unknown origin that most commonly occurs in women and usually has its onset in adolescence. Patients with AN invariably have a disturbed body image and an intense fear of weight gain. There is currently no definitive treatment for this disease, which carries a 20% mortality over 20 years. Development of an appropriate animal model of AN has been difficult, as the etiology of this eating disorder likely involves a complex interaction between genetic, environmental, social, and cultural factors. In this review, we focus on several possible rodent models of AN. In our laboratory, we have developed and studied three different mouse models of AN based on clinical profiles of the disease; separation stress, activity, and diet restriction (DR). In addition, we discuss the spontaneous mouse mutation anx/anx and several mouse gene knockout models, which have resulted in an anorexic phenotype. We highlight what has been learned from each of these models and possibilities for future models. It is hoped that a combination of the study of such models, together with genetic and clinical studies in patients, will lead to more rational and successful prevention/treatment of this tragic, and often fatal, disease. 相似文献