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51.
目的探讨不同视场角参数对虚拟环境中目标判断的影响规律 ,找出最佳视场角参数。方法利用自行研制基于PC平台的虚拟现实 (VR)实验系统 ,选定 45名年龄在 2 3~ 5 8岁被试者并完成大小与角度判断的实验设计。首先进行 30 0人次的预实验 ,确定引起虚拟环境中目标判断差错的视场角及相应观察任务的差别等级 ,然后开始单因素、4水平的完全随机正式实验。结果方差分析表明 ,不同的虚拟环境视场角对目标判断的真实性有显著性影响 ,当视场角为 60°时 ,目标判断的正确率最大。结论利用VR技术进行载人航天器工效设计、操作训练或其它任务的研究时 ,应考虑视场角的作用 ,适合目标大小判断的视场角参数值宜取 60°,以便获得最大的工效 相似文献
52.
重组人生长激素对老年人骨盆骨折蛋白质代谢及免疫功能的影响 总被引:1,自引:0,他引:1
目的 探讨应用重组人生长激素(recombinant human growth hormone,rhGH)对接受常规肠内营养支持的老年骨盆骨折患者蛋白质代谢及免疫功能的调理作用.方法 选择多发性骨盆骨折(骨折3处以上),年龄>70岁患者30例,随机分为2组: 治疗组15例,采用标准肠内营养 rhGH[rhGH 0.2U/(kg·d)皮下注射,共计8天];另外15例作为对照组,治疗前和治疗后的第8天,分别测定血清白蛋白、血清转铁蛋白、血清前白蛋白浓度、免疫球蛋白(IgA、IgG、IgM)、T淋巴细胞亚群(CD3、CD4、CD8),并统计医院获得性肺炎的发生情况.结果 治疗组患者在治疗后第8天的血清白蛋白、血清转铁蛋白和血清前白蛋白水平比对照组显著升高(P<0.05), IgA、IgG、IgM、CD3、CD4、CD4/CD8与对照组相比有明显增高(P<0.05);治疗组患者医院获得性肺炎的发生率也较对照组显著降低(P<0.05).结论 在肠内营养支持下加用rhGH可以明显促进老年骨盆骨折患者的蛋白质合成代谢,并改善免疫功能,增加肌肉的收缩力,增强排痰力度,减少医院获得性肺炎的发生率. 相似文献
53.
口外弓配合唇档远移磨牙的临床研究 总被引:1,自引:1,他引:0
目的:研究口外弓配合唇档远移磨牙的临床应用及其疗效。方法:选择15例恒牙早期上颌轻度牙性前突或轻、中度拥挤的安氏II类患者,应用口外弓配合唇档,通过X线头影测量观察其上颌磨牙及前牙治疗前后变化情况。结果:应用口外弓配合唇档推磨牙向远中3~6个月后,II类咬合关系恢复至安氏I类关系。上颌第一磨牙向远中平均移动4.14mm,上颌中切牙向唇侧移动0.66mm。结论:只要病例选择合适,方法运用得当,口外弓配合唇档就能获得较满意的远移磨牙的疗效。 相似文献
54.
The subdivisions of the sacral intermediolateral nucleus (IML) of the cat have been studied by using a double-labeling technique of retrograde Fluoro-gold (FG) and wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) tracing. The parasympathetic preganglionic neurons (PGNs) that were labeled by the FG injected into the pelvic nerve formed a ‘V’-shaped column known as the sacral parasympathetic nucleus (SPN) in the sacral IML. The neurons that were labeled by the WGA-HRP applied to the lateral parabrachial nucleus (PBL) formed an elongated spindle-shaped column extending throughout the IML of the sacral segments. We designated it by the name of sacral visceral sensory nucleus (SVSN). These findings indicate that the sacral IML of the cat contain two distinct subdivisions, SPN and SVSN. 相似文献
55.
The concave and convex rib-vertebral angle (RVA) at levels T2–T12 was measured on AP radiographs of 19 patients with right convex idiopathic thoracic scoliosis and 10 patients with major thoracic right convex neuromuscular scoliosis. The difference between the angles on the concave and the convex sides, the RVAD, was calculated. The RVAs were also measured on radiographs from three animal groups in which spinal curves had been induced experimentally in a variety of ways. Group 1 comprised 16 rabbits that had been subjected to selective electrostimulation of the latissimus dorsi, the erector spinae and the intercostal muscles. Group 2 comprised four dead rabbits whose spines had been subjected to manual bending. Group 3 comprised eight rabbits that had undergone mechanical elongation of one rib. In both the idiopathic and the neuromuscular group, the convex RVA was smaller than the concave RVA between levels T2 and T8, with a maximal difference between T4 to T5. From T9 to T12 the concave RVA was smaller than the convex. The RVA in relation to the scoliotic segment, i.e. the apex level of the curve and the two neighbouring vertebrae above and below this level, showed similar results. With increasing Cobb angle the RVADs increased linearly with the greatest difference at the second vertebra above the apex. In the three experimental groups the pattern of the RVADs between T6 to T12 was basically similar to the findings of the clinical study. From the results of these clinical and experimental studies, it is concluded that the typical pattern of the RVAs on the concave and convex sides seems to be independent of the underlying cause of the spinal curvature. It is likely that the RVADs result from a passive mechanical adaptation of the ribs to the lateral curvature of the spine. 相似文献
56.
Twenty women diagnosed with functional urinary incoordination were randomly assigned to one of two treatment groups: biofeedback or progressive muscle relaxation. Ten subjects who were placed on a waiting list prior to treatment allocation served as a comparison group. The biofeedback intervention focused specifically on retraining of pelvic floor musculature (PFM). Patients were assessed pretreatment, posttreatment, and at 2-month follow-up. Outcome measures included self-reported symptomatology, psychological functioning, psychophysiological assessment of the PFM, and urologist ratings of problem severity and treatment efficacy. Both treatment approaches proved effective in improving symptomatology and psychological state. Subjects on the waiting list demonstrated no change in urological difficulties. No differences were found between the two treatment groups on any of the outcome measures. Theoretical and practical implications of the results are discussed. 相似文献
57.
Athanasiou S Chaliha C Toozs-Hobson P Salvatore S Khullar V Cardozo L 《BJOG : an international journal of obstetrics and gynaecology》2007,114(7):882-888
Objective To evaluate the anatomy of the levator ani muscle in women with urogenital prolapse versus matched controls without prolapse using real-time two-dimensional (2-D) ultrasound.
Design Prospective observational study.
Setting Tertiary referral urogynaecology unit.
Population Forty-three women with pelvic organ prolapse (POP) and 24 women (controls) attending a gynaecology clinic without prolapse.
Methods All participants completed a standardised symptom questionnaire.
Main outcome measures The morphology of the vagina and paravaginal tissue was recorded at different levels. The thickness of the levator ani and the hiatal area were measured at rest. Reproducibility of the method was assessed by repeated measurements to assess intra-observer variability and inter-observer variability.
Results This method showed good intra-observer and inter-observer reproducibility and reliability. In controls, the pubococcygeus muscle showed more regular echogenicity with no evidence of trauma, whereas in women with prolapse the muscle had mixed echogenicity. ( P = 0.002). The mean thickness of the pubococcygeus did not differ between groups. The levator hiatal area was significantly larger in women with pelvic floor prolapse versus controls (17.8 cm2 versus 13.5 cm2 , P < 0.001). This increase in hiatal area positively and significantly correlated with prolapse severity ( P < 0.001).
Conclusions Morphology and hiatal area can be reliably imaged using 2-D ultrasound. Prolapse was related to changes in pelvic floor morphology and increased levator hiatal area. The use of 2-D ultrasound provides an important insight into the pathophysiology of prolapse. 相似文献
Design Prospective observational study.
Setting Tertiary referral urogynaecology unit.
Population Forty-three women with pelvic organ prolapse (POP) and 24 women (controls) attending a gynaecology clinic without prolapse.
Methods All participants completed a standardised symptom questionnaire.
Main outcome measures The morphology of the vagina and paravaginal tissue was recorded at different levels. The thickness of the levator ani and the hiatal area were measured at rest. Reproducibility of the method was assessed by repeated measurements to assess intra-observer variability and inter-observer variability.
Results This method showed good intra-observer and inter-observer reproducibility and reliability. In controls, the pubococcygeus muscle showed more regular echogenicity with no evidence of trauma, whereas in women with prolapse the muscle had mixed echogenicity. ( P = 0.002). The mean thickness of the pubococcygeus did not differ between groups. The levator hiatal area was significantly larger in women with pelvic floor prolapse versus controls (17.8 cm
Conclusions Morphology and hiatal area can be reliably imaged using 2-D ultrasound. Prolapse was related to changes in pelvic floor morphology and increased levator hiatal area. The use of 2-D ultrasound provides an important insight into the pathophysiology of prolapse. 相似文献
58.
目的 总结桥小脑角区巨大肿瘤的诊治经验。方法 对我科 73例桥小脑角区巨大肿瘤的发病率、临床和影像学表现、定位定性诊断、手术治疗及随访心理治疗结果作回顾性分析。结果 本组 73例桥小脑角巨大肿瘤 (均≥ 4cm)中 ,神经鞘瘤 50例 (68.4% )、脑膜瘤 1 9例 (2 6 .1 % )、胆脂瘤 4例 (5 .6 % )。 73例均有颅神经损害、小脑损害的症状与体征及颅内高压征。 73例中手术全切除 60例 (82 .2 % )、次全切除 1 3例 (1 7.8% )。 56例颅神经损伤中需心理治疗者 40例 (54 .8% ) ,2例死于肺部感染。平均随访 3 - 5年 ,无复发 ,疗效满意。结论 将桥小脑角区巨大肿瘤的临床特点结合影像学检查 ,可作早期定位、定性诊断 ,并有助于手术设计。早诊断、早治疗以及娴熟的显微操作技术是减少并发症 ,提高疗效的关键。手术结合伽玛刀以及随访心理治疗可改善预后 ,提高生存质量。 相似文献
59.
Summary
Extracorporeal shock wave lithotripsy (ESWL) is standard therapy for urolithiasis. With comparable technical principles, various
lithotripters have been developed and are in routine use. Renal pelvic stones, calyceal stones, ureteral stones, and other
special forms can be treated with varying results. Currently, the so-called clinically insignificant residual fragments and
the recurrence of calculi are under discussion. Whereas the side effects of ESWL are well known, studies comparing ESWL with
other endourological procedures are still lacking.
相似文献
60.
Standing posture is made possible by hip extension and lumbar lordosis. Lumbar lordosis is correlated with pelvic parameters, such as the declivity angle of the upper surface of the sacrum and the incidence angle, which determine the sagittal morphotype. Incidence angle, which is different for each individual, is known to be very important for upright posture, but its course during life has not yet been established. Incidence angle was measured on radiographs of 30 fetuses, 30 children and 30 adults, and results were analysed using the correlation coefficientr and Student's t test. A statistically significant correlation between age and incidence angle was observed. Incidence angle considerably increases during the first months, continues to increase during early years, and stabilizes around the age of 10 years. Incidence is a mark of bipedism, and its role in sagittal balance is essential. 相似文献