全文获取类型
收费全文 | 88987篇 |
免费 | 5927篇 |
国内免费 | 2738篇 |
专业分类
耳鼻咽喉 | 288篇 |
儿科学 | 2033篇 |
妇产科学 | 957篇 |
基础医学 | 7877篇 |
口腔科学 | 954篇 |
临床医学 | 13678篇 |
内科学 | 12438篇 |
皮肤病学 | 480篇 |
神经病学 | 3888篇 |
特种医学 | 5311篇 |
外国民族医学 | 5篇 |
外科学 | 10555篇 |
综合类 | 15445篇 |
现状与发展 | 7篇 |
预防医学 | 5757篇 |
眼科学 | 1116篇 |
药学 | 7648篇 |
82篇 | |
中国医学 | 7339篇 |
肿瘤学 | 1794篇 |
出版年
2024年 | 221篇 |
2023年 | 1187篇 |
2022年 | 2024篇 |
2021年 | 3221篇 |
2020年 | 3062篇 |
2019年 | 2491篇 |
2018年 | 2417篇 |
2017年 | 2578篇 |
2016年 | 2686篇 |
2015年 | 2692篇 |
2014年 | 5167篇 |
2013年 | 5923篇 |
2012年 | 4693篇 |
2011年 | 5197篇 |
2010年 | 4250篇 |
2009年 | 4020篇 |
2008年 | 4120篇 |
2007年 | 4380篇 |
2006年 | 3838篇 |
2005年 | 3561篇 |
2004年 | 3124篇 |
2003年 | 2947篇 |
2002年 | 2529篇 |
2001年 | 2452篇 |
2000年 | 1981篇 |
1999年 | 1657篇 |
1998年 | 1519篇 |
1997年 | 1519篇 |
1996年 | 1204篇 |
1995年 | 1189篇 |
1994年 | 1118篇 |
1993年 | 867篇 |
1992年 | 856篇 |
1991年 | 760篇 |
1990年 | 598篇 |
1989年 | 579篇 |
1988年 | 561篇 |
1987年 | 465篇 |
1986年 | 430篇 |
1985年 | 604篇 |
1984年 | 503篇 |
1983年 | 313篇 |
1982年 | 453篇 |
1981年 | 342篇 |
1980年 | 306篇 |
1979年 | 224篇 |
1978年 | 182篇 |
1977年 | 166篇 |
1976年 | 152篇 |
1975年 | 78篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
111.
目的 比较高血压合并阻塞性睡眠呼吸暂停患者的短期血压变异性。方法 将155例分为对照组、高血压组、高血压合并轻度或中重度阻塞性睡眠呼吸暂停组,EE较患者不同活动状态的短期血压变异性。结果 高血压合并中重度阻塞性睡眠呼吸暂停组患者睡眠期间和早晨血压变异系数分别为:收缩压18.69、21.32;舒张压19.41、23.61,明显高于其他各组。结论 夜间睡眠期间和早晨短期血压变异性增加,是高血压合并中重度阻塞性睡眠呼吸暂停患者夜间和早晨心血管事件发生率增加的重要危险因素。 相似文献
112.
V. Pursiainen J. T. Korpelainen T. H. Haapaniemi K. A. Sotaniemi V. V. Myllylä 《European journal of neurology》2007,14(4):373-378
Our study aimed to investigate the cardiovascular autonomic regulation related to the wearing-off phenomenon in Parkinson's disease (PD). We measured blood pressure (BP) and heart rate (HR) at rest and during orthostatic test in 16 patients with PD with wearing-off and in 15 patients with PD without wearing-off both before (baseline) and repetitively at 1-h intervals for up to 4 h after the morning PD medication dose.
The patients with wearing-off had fluctuation of BP during the observation period, BP increasing when the motor performance worsened and vice versa. The mean supine BP was at its highest at the baseline measurement (patients with wearing-off, 145 ± 18 mmHg; patients without wearing-off, 138 ± 17 mmHg), fell during the first hour (patients with wearing-off, 119 ± 17 mmHg; patients without wearing-off, 126 ± 18 mmHg), and then rose again toward the end of the observation period (patients with wearing-off, 136 ± 15 mmHg; patients without wearing-off, 138 ± 18 mmHg). This BP change was statistically significant only in PD patients with wearing-off ( P < 0.001).
In conclusion, BP seems to fluctuate with motor impairment in PD patients with wearing-off. This fluctuation may represent autonomic dysfunction caused by the PD process itself, the effect of PD medication, or both. 相似文献
The patients with wearing-off had fluctuation of BP during the observation period, BP increasing when the motor performance worsened and vice versa. The mean supine BP was at its highest at the baseline measurement (patients with wearing-off, 145 ± 18 mmHg; patients without wearing-off, 138 ± 17 mmHg), fell during the first hour (patients with wearing-off, 119 ± 17 mmHg; patients without wearing-off, 126 ± 18 mmHg), and then rose again toward the end of the observation period (patients with wearing-off, 136 ± 15 mmHg; patients without wearing-off, 138 ± 18 mmHg). This BP change was statistically significant only in PD patients with wearing-off ( P < 0.001).
In conclusion, BP seems to fluctuate with motor impairment in PD patients with wearing-off. This fluctuation may represent autonomic dysfunction caused by the PD process itself, the effect of PD medication, or both. 相似文献
113.
Book reviews in this article: Fifty athletes with chronic undiagnosed groin pain underwent surgical exploration and inguinal hernia repair. Six months later, all athletes were sent questionnaires to assess their return to sport, level of pain (using analogue pain scores) and the overall result of their surgery. Operative findings revealed a significant bulge in the posterior inguinal wall in 40 athletes. Forty-four athletes (88%) replied to the questionnaire. Forty-one athletes (93% of respondents) had returned to normal activities. Pain scores indicated a marked improvement in their level of pain (P < 0.001). Thirty-three athletes (75%) rated the result as good and 10 (23%) as improved. It is concluded that athletes with chronic groin pain who are unable to compete in active sport should be considered for routine inguinal hernia repair if no other pathology is evident after clinical examination and investigation. 相似文献
114.
115.
116.
117.
P. G. Slattery 《ANZ journal of surgery》1994,64(11):768-770
The author has recently had referred to him three patients with median nerve injuries who have had open carpal tunnel decompression via a small transverse wrist incision. Despite previous adverse reports, some surgeons persist with this technique. 相似文献
118.
119.
高效液相色谱法测定微量耳血中头孢他定的浓度 总被引:2,自引:0,他引:2
本文介绍采取微量耳血以高效液相色谱法测定头孢他定(Ceftazidime)的血药浓度。血样经6%高氯酸沉淀蛋白,流动相为含25%甲醇的0.05mol/L醋酸铵溶液,以冰醋酸调节pH值至4~5,检测波长为254nm,内标物为头孢唑啉(Cefazolin)。经对家兔采取微量耳血测定其血药浓度,可知头孢他定为二室模型,T_1/2α为0.18±0.05h,T_1/2β为1.75±0.07h。并对3名住院病人静脉注射1g头孢他定后定时分别取微量耳血进行分析,所得结果与文献基本一致。本文方法简便、快速,结果令人满意。 相似文献
120.
A. Queirós J. M. González-Méijome P. Fernandes J. Jorge J. B. Almeida M. A. Parafita 《Ophthalmic & physiological optics》2006,26(4):384-391
PURPOSE: The main objectives of this study were to determine the differences between non-synchronized intraocular pressure (IOP_N) and intraocular pressure readings synchronized with cardiac pulse and try to determine if these parameters are related to blood pressure values. METHODS: One hundred and sixty-five right eyes from 165 volunteers (107 females, 58 males) aged from 19 to 73 years (mean +/- S.D., 29.93 +/- 11.17) were examined with the Nidek NT-4000, a new non-contact tonometer that allows the measurement of IOP synchronized with the cardiac rhythm. IOP measurements in the four different modes of synchronization were taken in a randomized order. Three measures of each parameter were taken and then averaged. The blood pressure was determined three times with a portable manometer and mean values of systolic and diastolic pressure and the pulse rate were computed. Mean arterial pressure (MAP) was determined as being 1/3 of systolic plus 2/3 of diastolic blood pressure. RESULTS: The mean +/- S.D. values for the standard intraocular pressure (IOP_N: 14.76 +/- 2.86), intraocular pressure in the systolic instant or peak (IOP_P: 14.99 +/- 2.85), intraocular pressure in the middle instant between heartbeats or middle (IOP_M: 14.68 +/- 2.76), and intraocular pressure in the diastolic instant or bottom (IOP_B: 13.86 +/- 2.61) were obtained. The IOP_P was higher than the remaining values. A significant difference in mean IOP existed between IOP_B and the remaining modes of measuring (p < 0.05). Differences were statistically significant for all pair comparisons involving IOP_B. Arterial blood pressure values were systolic 125.5 +/- 14.22, diastolic 77.7 +/- 8.38 and MAP 93.64 +/- 9.44 mmHg. The pulse rate was 77.3 +/- 12.6 beats per minute. Except for the MAP (p = 0.025) there was no significant correlation between different IOP values and systolic or diastolic blood pressure, or pulse rate. CONCLUSIONS: NT-4000 is able to differentiate IOP values when synchronized with the cardiac rhythm and those differences are expected to be within a range of +/-2.5 to +/- 3.0 mmHg. IOP_B seems to be the parameter whose value differs from the non-synchronized and the remaining synchronized parameters in a significant way. Other than a weak association with MAP, no significant correlation between IOP and BP was found. The measurements of IOP readings for the three modes are consistent with timings during the cardiac cycle and IOP pulse cycle. 相似文献