首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   9304篇
  免费   1025篇
  国内免费   173篇
耳鼻咽喉   41篇
儿科学   26篇
妇产科学   17篇
基础医学   279篇
口腔科学   352篇
临床医学   511篇
内科学   260篇
皮肤病学   35篇
神经病学   119篇
特种医学   151篇
外国民族医学   2篇
外科学   383篇
综合类   1182篇
预防医学   195篇
眼科学   6233篇
药学   449篇
  5篇
中国医学   231篇
肿瘤学   31篇
  2024年   32篇
  2023年   165篇
  2022年   204篇
  2021年   397篇
  2020年   350篇
  2019年   319篇
  2018年   369篇
  2017年   364篇
  2016年   436篇
  2015年   408篇
  2014年   576篇
  2013年   696篇
  2012年   595篇
  2011年   666篇
  2010年   478篇
  2009年   508篇
  2008年   440篇
  2007年   454篇
  2006年   447篇
  2005年   348篇
  2004年   300篇
  2003年   225篇
  2002年   186篇
  2001年   174篇
  2000年   186篇
  1999年   139篇
  1998年   120篇
  1997年   75篇
  1996年   64篇
  1995年   66篇
  1994年   47篇
  1993年   48篇
  1992年   73篇
  1991年   40篇
  1990年   42篇
  1989年   44篇
  1988年   24篇
  1987年   29篇
  1986年   17篇
  1985年   73篇
  1984年   50篇
  1983年   43篇
  1982年   44篇
  1981年   45篇
  1980年   48篇
  1979年   15篇
  1978年   17篇
  1977年   7篇
  1976年   4篇
  1973年   2篇
排序方式: 共有10000条查询结果,搜索用时 156 毫秒
51.
Background: The slitlamp can be used to estimate the anterior chamber depth (ACD). The length of a slit object is increased until the corneal and iris/lens images appear to just touch. Multiplying the just‐touching‐slit‐length (JTSL) by a conversion factor gives an estimate of the ACD as measured by ultrasonography. The purpose of this study was to determine if central corneal thickness (CCT) affects the accuracy of this technique. Methods: The ACD of 50 subjects was measured by A‐scan ultrasonography and estimated by the slitlamp technique. CCT was measured by ultrasonic pachometry. The refractive error was determined subjectively. Results: The average ultrasonographic ACD for all subjects was 3.32 ± 0.65 mm. The average JTSL was 2.46 ± 0.38 mm. The conversion ratio between the ultrasonographic ACD and the average JTSL was 1.35. The predicted ACD using the regression equation of JTSL on the ultrasound anterior chamber depth (USACD) was 3.32 ± 0.54 mm. The corresponding value using the regression equation of JTSL and CCT on USACD was exactly the same, that is, 3.32 ± 0.54 mm. Conclusion: Incorporation of CCT into a regression equation does not improve the accuracy of the Smith technique.  相似文献   
52.
Drug-induced secondary angle closure is quite common and in the majority of cases simply stopping the medication leads to rapid reversal of the condition and resolution of glaucoma. We describe here a patient who presented with secondary angle closure glaucoma and myopia following mefenamic acid ingestion which was managed successfully by stopping the medication, symptomatic treatment and reassurance.  相似文献   
53.
In this paper we describe Bonferroni‐based multiple testing procedures (MTPs) as strategies to split and recycle test mass. Here, ‘test mass’ refers to (parts of) the nominal level α at which the family‐wise error rate is controlled. Briefly, test mass is split between different null hypotheses, and whenever a null hypothesis is rejected, the part of α allocated to it may be recycled to the testing of other hypotheses. These recycling MTPs are closed testing procedures based on raw p‐values associated with testing the individual null hypotheses, and the class of such MTPs includes, for example, serial and parallel gatekeeping, fallback and Holm procedures. Graphical displays and a concise algebraic notation are provided for such MTPs. This recycling approach has pedagogical advantages and may facilitate the tailoring of MTPs for different purposes. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
54.
目的:探讨抗青光眼餐引流术后的白内障患眼进行超声乳化吸除术的手术入路,操作方式及临床效果。方法:避开功能性滤过泡,选择角巩膜隧道切口或透明角膜切口,瞳孔麻痹性散大时,做一个完美的直径约5mm的连续环形撕囊以补偿之;恰当处理虹膜后粘连后,在病理性小瞳孔下完成超声乳化手术;眼压失控者行青光眼白内障人工晶体植入三联术。结果:无后囊破裂,人工晶体全部囊袋内植入,术后1周视力≥0.5者20只眼(64.5%),0.1-0.4者8只眼(25.8%),<0.1者3只眼(9.7%)。随访1-16个月,眼压均在20.55mmHg以下。结论:体外流术后的白内障患眼,超声乳化手术因其切口小,并发症少,不破坏功能性滤过泡,不损伤瞳孔,是目前各种手术方法中的最佳选择。  相似文献   
55.
派立明与贝特舒联合应用对降眼压的临床观察   总被引:1,自引:0,他引:1  
目的评价1.00%派立明(AZOPT)与0.25%贝特舒点眼液每日两次点眼对原发性开角型青光眼、高眼压症及抗青光眼术后高眼压的降眼压效果及安全性。方法31例患者51只眼纳入为期2个月的前瞻性研究。在停用其他抗青光眼药物足够长的时间后测量基础值,用药后每2周复查一次共4次,同时观察眼局部及全身副作用。结果用药前眼压为23.85±1.80 mmHg,4次随访眼压下降均值6.55 mmHg(6.06~7.04),眼压下降率27.50%(26.62~28.59%)。少数病例出现烧灼感、视物模糊、口苦等症状,均为轻度能耐受,对视力、眼底无影响。结论派立明与贝特舒联合用药具有稳定的降眼压效果,具良好耐受性。  相似文献   
56.
Pattern electroretinograms (PERGs) in response to 8.3 Hz alternating gratings (16.6 rev/sec) of different spatial frequencies were recorded in normal subjects as well as in patients affected by early glaucoma and ocular hypertension. In normal subjects the PERG response is spatially tuned, with a maximum at about 1.5 cycles/deg and attenuation at higher and lower spatial frequencies. In all cases of early glaucoma and in the great majority of cases of ocular hypertension the PERG was reduced, as compared with that of normal subjects, mainly in the medium range of spatial frequencies (at which the PERG has its maximal amplitude).  相似文献   
57.
目的:探讨小梁切除联合丝裂霉素术后晚期滤泡相关并发症的发生率及处理。 方法:1994-05/2000.05接受小梁切除手术联合丝裂霉素治疗青光眼65例65眼,采用Kaplan-Meier生存分析法估计晚期滤过泡渗漏、滤泡炎、眼内炎的发生概率。 结果:随访2.5~7.1(平均5.6)a,发生滤过泡渗漏16眼(16/65,24.6%),出现滤泡炎5眼(5/65,7.7%),发生眼内炎1眼,出现复合性滤泡并发症1眼,出现持久性低眼压9眼(9/65,13.8%)。Kaplan-Meier生存分析法估计晚期滤泡并发症5a发生概率为40.0%。多数眼通过门诊处理获得成功,部分眼需手术治疗。 结论:小梁切除联合丝裂霉素术后晚期滤泡相关并发症的发生率可高达40.0%,单纯滤过泡渗漏是一相对良性的状况,只要及时处理,可被修复,滤泡炎或眼内炎可以被控制,而获得正常眼内压。一相对良性的状况,只要及时处理,可被修复,滤泡炎或眼内炎可以被控制,而获得正常眼内压。  相似文献   
58.
The literature suggests that visual field defects may be more common in people who experience migraine. The Humphrey frequency doubling (FDT) visual field instrument selectively examines the magnocellular visual pathway, but has not previously been used to investigate visual function in migraine. In a masked controlled study we compared Humphrey FDT and Humphrey Swedish Interactive Threshold Algorithm fields of 25 migraine sufferers with 25 age- and gender-matched controls. Although both mean deviation and pattern standard deviation were a little worse in the migraine group, these differences did not reach statistical significance. There were no inter-eye visual field differences in the migraine group compared with controls. Comparing the mean of all the contrast thresholds in each hemisphere, there were no more inter-hemifield visual field differences in the migraine group compared with controls. There was no significant difference between the migraine and control groups in intra-ocular pressures. The visual field parameters were not correlated with the interval since the last migraine headache, the severity of migraine headache, the duration of migraine headache or the number of migraine headaches per annum. In our data, there was no evidence of visual field deficits, a magnocellular deficit, or indications of glaucomatous pathology.  相似文献   
59.
目的 :观察丝裂霉素C(MMC)在抗青光眼手术中应用的近期及远期效果。方法 :4 2只复发性青光眼在二次手术中一次性应用MMC术后观察及随访。结果 :术前眼压 34.0 5± 4 .0 5mmHg ,明显高于随访半年期 13.13± 3.30mmHg以及随访 2年期 14 .33± 3.30mmHg ,差异有显著性 (P <0 .0 1)。术后近期眼压 6 .75± 1.4 3mmHg ,明显低于随访半年期 (P <0 .0 1)。功能性滤过泡所占比率为 95 .2 %。结论 :术中一次性应用MMC ,远期观察其降压效果明显 ,且无严重并发症发生  相似文献   
60.
目的 研究非穿透性小梁切除术治疗开角型青光眼的手术效果。方法 对20例26眼开角型青光眼行非穿透性小梁切除术,术后观察眼压、结膜滤枕及前房反应等情况,随访1~12个月。结果 术后各期平均眼压均低于术前平均眼压,差异有显著性(P<0.05)术。前平均眼压26.26mmHg,术后3个月、6个月、9个月、12个月平均眼压分别为15.47mmHg、16.89mmHg、19.14mmHg、18.50mmHg。16眼结膜形成滤性手术典型滤过泡,10眼结膜疏松无滤过泡形成。26眼均无前房出血,术后前房反应轻。结论 非穿透性小梁切除术能有效地降低开角型青光眼的眼压,术后并发症少,可作为此类青光眼病人手术的选择。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号