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991.
Objective:To evaluate the feasibility and safety of prenatal diagnosis by traneabdominal chorionic villus sam-pling(TA-CVS)via the guidance of B-mode ultrasound in the first trimester of gestation.To explore the technique of long time culture and chromosome preparation of villi in early pregnancy.To evaluate the feasibility of the above techniques in the application of the prenatal cytogenetic diagnosis.Methods:One hundred and thirty-five singleton pregnancies at risk were referred from January 2001 to Decem-ber 2007.Results:The average maternal age was 35.2 years.TA-CVS was performed in the 10~13th weeks of gestation and the average gestational age was 10.89 weeks.All attempts at sampling were successful.The rate of operation-associated fetal loss was 0.74%.The failure rate of prenatal diagnosis because of inadequate amount of specimen was 0.The average culture time was 5-7 days.The success rate of the cell culture was 98.5%.No maternal con-temination and bacterial contamination happened.Fifteen cases of abnormal karyotype and one case of confined pla-cantel mosaiciem were diagnosed.Conclusion:TA-CVS appears to be safe and feasible and might to be offered in the prenatal diagnosis in the first trimester of gestation.The technique of long time culture and chromosome preparation of villi is stable and reliable.It is feasible to apply these techniques in the clinical practice of prenatal cytogenetic diagnose in the early pregnancy. 相似文献
992.
993.
Yao-Jong Yang Shih-Min Wang Chun-Ta Chen Mei-Chih Huang Chih-Jen Chang Ching-Chuan Liu 《台湾医志》2003,102(6):375-378
BACKGROUND AND PURPOSE: Helicobacter pylori infection is primarily acquired in early childhood and its transmission routes are debated. The aims of this study were to determine the seroprevalence of anti-H. pylori immunoglobulin G (IgG) in Taiwanese and to investigate whether a common mode of transmission could be shared between H. pylori and hepatitis A virus (HAV). METHODS: An enzyme-linked immunosorbent assay (ELISA) was used to investigate the prevalence of H. pylori among 924 healthy volunteers aged less than 40 years, and radioimmunoassay for HAV infection was conducted in 500 subjects from the same population. The kappa statistic was used to measure the difference in positivity for the 2 infections in a subgroup of 500 subjects who had their sera simultaneously tested for anti-H. pylori and anti-HAV antibodies. RESULTS: The seroprevalence of anti-H. pylori IgG was 16.7% in subjects aged < 16 years and 38.3% at ages >or= 16 years. Most children (99%) under the age of 16 were seronegative for HAV. The prevalence of H. pylori infection increased rapidly with age, at 1%/year and 0.8%/year for children and adults, respectively. The rate of H. pylori infection was higher in male (21%) than in female (12%) children (p < 0.01; OR, 2.0; 95% confidence interval, 1.2 to 3.0). No significant difference in seroprevalence between genders was noted in subjects aged >or= 16 years. The agreement in the trend of seropositivity between both infections in the age groups 1 to 10 years and 10 to 20 years was worse than chance (kappa = -0.56) and little better than chance (kappa = 0.01), respectively. CONCLUSIONS: Acquisition of H. pylori infection occurs at a young age, and male children are more likely to develop the infection. The main transmission route of HAV, the fecal-oral route, did not seem to be responsible for H. pylori transmission in this Taiwanese cohort. 相似文献
994.
Gregory M. Marcus MD Yanfei Yang MD Paul D. Varosy MD Karen Ordovas MD Zian H. Tseng MD Nitish Badhwar MBBS Byron K. Lee MD Randall J. Lee MD Melvin M. Scheinman MD Jeffrey E. Olgin MD 《Heart rhythm》2007,4(2):138-144
BACKGROUND: Regional differences in fibrosis, particularly related to the posterior wall and septum, may be important in atrial fibrillation (AF). Using electroanatomic mapping, voltage can be used as a measure of fibrosis. OBJECTIVES: The purpose of this study was to determine if patients with AF have disproportionately lower voltage in the septal and posterior walls of the left atrium. METHODS: Sinus rhythm left atrial electroanatomic maps were used in serial patients presenting for left atrial ablation of AF (8-mm tip). Patients undergoing left atrial mapping for focal atrial tachycardia (AT) were used as a comparison group (4-mm tip). Animal experiments were performed to assess the influence of ablation catheter tip size on voltage amplitude. RESULTS: The posterior and septal walls exhibited the lowest voltages in both groups. Compared with the anterior wall, there was a 3.78-fold greater odds of finding a low-voltage point (<0.5 mV) in the septum (P <.001) and a 3.37-fold greater odds of finding a low-voltage point in the posterior wall (P <.001) in the AF patients; the proportion of low-voltage points by region were not significantly different in the AT group. In the animal model, the mean voltage obtained from an 8-mm ablation catheter was significantly higher (0.30 +/- 0.17 mV) than that obtained from the same points using a 4-mm catheter (0.22 +/- 0.17, P = .05). CONCLUSION: Regional differences in voltage are present in patients with atrial arrhythmias, with AF patients exhibiting significantly more low-voltage areas in the septum and posterior walls. 相似文献
995.
996.
经尿道前列腺电汽化术治疗前列腺增生(附386例报告) 总被引:2,自引:0,他引:2
目的探讨经尿道前列腺电汽化术(TVP)治疗前列腺增生的疗效。方法回顾分析采用经尿道前列腺电汽化术治疗386例前列腺增生(BPH)患者的临床资料。结果术中发生前列腺包膜穿孔2例,电切综合征(TURS)1例。术后随访1月-5年,术后3月内出血6例,前列腺尖部黏连狭窄1例,远期出血2例发生在术后1-3年。术后3个月最大尿流率(Qmax)12.3-23.5mL/s,平均18.5mL/s;IPSS评分6-17分,平均9.5分。结论经尿道电汽化术治疗前列腺增生效果明显,腺体残留是术后出血、排尿困难的主要原因。 相似文献
997.
光-电一体化技术在美容医学领域的兴起与发展 总被引:9,自引:9,他引:0
目的介绍光-电一体化技术的机理、适应证的选择、疗效、及并发症和注意事项。方法经文献复习,此项技术的产品有两种类型:①射频与强脉冲光;②射频与激光联合。两种技术发出的能量,分别作用于真皮深层和浅层以及筋膜层,使真皮胶原增厚,以达到皮肤年轻化,并可用于治疗色素沉着、血管病灶、脱毛和痤疮等。电能(RF)40~100J/cm^3,光能15~50J/cm^2。结果根据Fzpatrick皮肤分类和Glogau皱纹分类,选用不同的参数,才能取得好的结果。Bitter和Mulholland报道的Aurora SR设备,皮肤年轻化效果达92%~98%,仅有2%~8%不满意;脱毛效果达80%~85%,20%轻度红斑,24h消失,有8%暂时性色素沉着;下肢静脉扩张最后一次治疗1~6个月,约77%治疗区中有75%~100%扩张血管消失,对桔皮症也取得了较好的效果。结论此项技术的疗效是肯定的,并发症和不良反应少而轻,无不可治愈的不良反应。不同肤色和皱纹选用恰当的治疗参数,是取得满意疗效的保证。 相似文献
998.
Hanbing Lu Clara A Scholl Yantao Zuo Elliot A Stein Yihong Yang 《Magnetic resonance in medicine》2007,58(3):616-621
In cerebral blood volume (CBV)-weighted functional MRI (fMRI) employing superparamagnetic contrast agent, iron dose and blood oxygenation level dependent (BOLD) contamination are two important issues for experimental design and CBV quantification. Both BOLD and CBV-weighted fMRI are based upon the susceptibility effect, to which spin-echo and gradient-echo sequences have different sensitivities. In the present study, CBV-weighted fMRI was conducted using spin-echo and gradient-echo sequences at 9.4T by systematically changing the doses of contrast agent. Results suggest that BOLD contamination is a significant component in CBV-weighted fMRI at high field, particularly when relatively low dose of contrast agent is administered. A mathematical model was developed to quantify the extravascular (EV) BOLD effect. With a TE of 35 ms, the EV BOLD effect was estimated to account for 76+/-12% of the observed spin-echo fMRI signal at 9.4T. These data suggest that correcting BOLD effect may be necessary for accurately quantifying activation-induced CBV changes at high field. 相似文献
999.
目的 研究caspase-3反义寡核苷酸对6-OHDA诱导大鼠中脑多巴胺神经元凋亡的保护作用.方法 向四组SD大鼠的中脑黑质部位注入反义、错义、正义寡核苷酸及NS,然后再注入6-OHDA,取中脑做连续切片,原位杂交及免疫组化检测黑质caspase-3的表达及TH的表达,原位末端标记法(Tunel)检测黑质细胞的凋亡.结果 反义组Tunel阳性细胞数为82±8.6,方差分析显示反义组阳性细胞数显著性低于其他各组(P<0.05);反义组手术侧TH阳性细胞数为168.6±11.4,与对侧阳性细胞比值为63%±11.3%,显著性高于其余各组(P<0.05).结论 有效阻断caspase-3的表达可减轻6-OHDA诱导的多巴胺神经元凋亡,caspase-3可作为保护性治疗帕金森病的靶点. 相似文献
1000.
高效液相色谱/质谱法检测人尿中的糖皮质激素及其它兴奋剂 总被引:2,自引:0,他引:2
采用液相色谱/质谱(LC/MS)方法检测糖皮质激素、甾体和β2激动剂。本文采用Zorbax 30 mm×2.1mm,1.8μm短柱,对12种糖皮质激素、3种甾体和2种β2激动剂的液相色谱/质谱的测定方法进行了研究,建立了6分钟内快速检测人尿中多种糖皮质激素、甾体和β2激动剂的测定方法。检测限低于5ng/ml。该方法适用于兴奋剂的筛选及确证。 相似文献