全文获取类型
收费全文 | 50953篇 |
免费 | 4006篇 |
国内免费 | 1597篇 |
专业分类
耳鼻咽喉 | 471篇 |
儿科学 | 1466篇 |
妇产科学 | 933篇 |
基础医学 | 7644篇 |
口腔科学 | 947篇 |
临床医学 | 4807篇 |
内科学 | 8370篇 |
皮肤病学 | 369篇 |
神经病学 | 4429篇 |
特种医学 | 2231篇 |
外国民族医学 | 3篇 |
外科学 | 6276篇 |
综合类 | 5032篇 |
现状与发展 | 7篇 |
预防医学 | 4136篇 |
眼科学 | 806篇 |
药学 | 5581篇 |
10篇 | |
中国医学 | 1646篇 |
肿瘤学 | 1392篇 |
出版年
2024年 | 135篇 |
2023年 | 853篇 |
2022年 | 1715篇 |
2021年 | 2365篇 |
2020年 | 2048篇 |
2019年 | 2031篇 |
2018年 | 1973篇 |
2017年 | 1683篇 |
2016年 | 1487篇 |
2015年 | 1604篇 |
2014年 | 3021篇 |
2013年 | 3240篇 |
2012年 | 2499篇 |
2011年 | 2936篇 |
2010年 | 2433篇 |
2009年 | 2419篇 |
2008年 | 2432篇 |
2007年 | 2483篇 |
2006年 | 2041篇 |
2005年 | 1806篇 |
2004年 | 1618篇 |
2003年 | 1430篇 |
2002年 | 1180篇 |
2001年 | 1016篇 |
2000年 | 851篇 |
1999年 | 773篇 |
1998年 | 793篇 |
1997年 | 808篇 |
1996年 | 720篇 |
1995年 | 597篇 |
1994年 | 555篇 |
1993年 | 499篇 |
1992年 | 472篇 |
1991年 | 472篇 |
1990年 | 395篇 |
1989年 | 346篇 |
1988年 | 316篇 |
1987年 | 261篇 |
1986年 | 224篇 |
1985年 | 307篇 |
1984年 | 269篇 |
1983年 | 164篇 |
1982年 | 233篇 |
1981年 | 212篇 |
1980年 | 167篇 |
1979年 | 151篇 |
1978年 | 142篇 |
1977年 | 111篇 |
1976年 | 112篇 |
1975年 | 45篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
《Clinical neurophysiology》2020,131(1):259-264
ObjectivesFasciculation potentials (FP) are an important consideration in the electrophysiological diagnosis of ALS. Muscle ultrasonography (MUS) has a higher sensitivity in detecting fasciculations than electromyography (EMG), while in some cases, it is unable to detect EMG-detected fasciculations. We aimed to investigate the differences of FP between the muscles with and without MUS-detected fasciculations (MUS-fas).MethodsThirty-one consecutive patients with sporadic ALS were prospectively recruited and in those, both needle EMG and MUS were performed. Analyses of the amplitude, duration, and number of phases of EMG-detected FPs were performed for seven muscles per patient, and results were compared between the muscles with and without MUS-fas in the total cohort.ResultsThe mean amplitude and phase number of FP were significantly lower in patients with EMG-detected FP alone (0.39 ± 0.25 mV and 3.21 ± 0.88, respectively) than in those with both FP and MUS-fas (1.22 ± 0.92 mV and 3.74 ± 1.39, respectively; p < 0.0001 and p = 0.017, Welch’s t-test).ConclusionSmall FP may be undetectable with MUS. MUS cannot replace EMG in the diagnostic approach for ALS.SignificanceClinicians should use a combination of EMG and MUS for the detection and quantitative analysis of fasciculation in ALS. 相似文献
13.
《Clinical gastroenterology and hepatology》2022,20(5):1112-1121.e4
- Download : Download high-res image (419KB)
- Download : Download full-size image
14.
《Biomaterials》2015
Controlling cellular alignment is critical in engineering intestines with desired structure and function. Although previous studies have examined the directional alignment of cells on the surface (x–y plane) of parallel fibers, quantitative analysis of the cellular alignment inside implanted scaffolds with oriented fibers has not been reported. This study examined the cellular alignment in the x–z and y–z planes of scaffolds made with two layers of orthogonally oriented fibers. The cellular orientation inside implanted scaffolds was evaluated with immunofluorescence. Quantitative analysis of coherency between cell orientation and fiber direction confirmed that cells aligned along the fibers not only on the surface (x–y plane) but also inside the scaffolds (x–z & y–z planes). Our study demonstrated that two layers of orthogonally aligned scaffolds can generate the histological organization of cells similar to that of intestinal circular and longitudinal smooth muscle. 相似文献
15.
16.
目的 研究主、被动最大张口度(AMMO、PMMO)与颞下颌关节强直严重程度的关系。方法 选取28只健康雄性绵羊随机分为实验组和对照组,每组各14只。实验组绵羊双侧颞下颌关节模拟髁突矢状骨折,其中左侧翼外肌被切断以阻断其功能;对照组绵羊未进行手术。于术前及术后12、24周对所有绵羊体重、AMMO、PMMO、颞下颌关节形态学特点进行测量评估。结果 实验组只有右侧保留翼外肌功能的颞下颌关节发生了骨强直。术后12、24周,实验组绵羊AMMO、PMMO、极限距离均显著低于对照组,差异均有统计学意义(均P < 0.05)。实验组绵羊AMMO和PMMO与骨融合区宽度、长度、面积及钙化程度均呈负相关(均P < 0.05),其中骨融合区面积为主要影响因素(术后12、24周相关系数r分别为-0.94、-0.95)。结论 颞下颌关节强直动物模型中阻断翼外肌功能可阻止骨强直的发生;对于早期髁突矢状骨折,可通过牙合垫或牙合板进行张口训练,进而阻断翼外肌功能。当颞下颌关节发生骨强直时,骨融合区面积越大,张口受限越明显。 相似文献
17.
Aging alters bladder functions where a decrease in filling, storage and emptying is observed. These changes cause urinary incontinence, especially in women. The aim of this study is to examine how aging affects the intracellular calcium movements due to agonist-induced contractions in permeabilized female rat bladder. Urinary bladder isolated from young and old female Sprague-Dawley rats were used. Small detrusor strips were permeabilized with β-escin. The contractile responses induced with agonists were compared between young and old groups. Carbachol-induced contractions were decreased in permeabilized detrusor from old rats compared to young group. Heparin and ryanodine decreased carbachol-induced contractions in young rats where only heparin inhibited these contractions in olds. Caffeine-induced contractions but not inositol triphosphate (IP3)-induced contractions were decreased in old group compared to youngs. The cumulative calcium response curves (pCa 8–4) were also decreased in old rats. Carbachol-induced calcium sensitization responses did not alter by age where GTP-β-S and GF-109203X but not Y-27632 inhibited these responses. Carbachol-induced contractions decrease with aging in rat bladder detrusor. It can be postulated as IP3-induced calcium release (IICR) is primarily responsible for the contractions in older rats where the decrease in carbachol contractions in aging may be as a result of a decrease in calcium-induced calcium release (CICR), rather than carbachol-induced calcium sensitization. 相似文献
18.
《Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society》2020,28(11):1412-1426
19.
To evaluate the anthropometric indexes in subjects with varicocele compared to controls and the incidence of varicocele in different body mass index (BMI) groups for the purpose of exploring the association between varicocele and anthropometric indexes. A comprehensive literature search was conducted by using PubMed, MEDLINE, EMBASE databases and Cochrane Library up to February 2019. A systematic review and meta‐analysis was conducted by STATA, and Newcastle–Ottawa Scale was utilised for assessing risk of bias. Ultimately, 13 articles containing seven case–control studies and six cross‐sectional studies with 1,385,630 subjects were involved in our study. Pooled results demonstrated that varicocele patients had a lower BMI (WMD = ?0.77, 95% CI = ?1.03 to ?0.51) and a higher height than nonvaricocele participants, especially in grade 3 varicocele patients. Subgroup analyses showed that normal BMI individuals had a higher risk of varicocele than obese or overweight individuals and a lower risk than underweight individuals. In conclusion, this study indicates that varicocele patients have a lower BMI and a higher height than nonvaricocele participants. Moreover, men with excess bodyweight have a lower incidence of varicocele compared to normal weight or underweight people. That is to say, high BMI and adiposity protect against varicocele and high BMI is associated with a decreased risk of varicocele. 相似文献
20.
《Primary Care Diabetes》2019,13(6):568-573
AimsTo compare postprandial glucose responses to high-intensity interval exercise (HIE) between obese and lean individuals.MethodsThirty healthy young adult males (15 obese, 15 lean) ate a standardised meal, then performed HIE (4 × 30-s Wingate cycling/4-min rest) or a no-exercise control trial (CON). Blood glucose was measured preprandially and up to 150 min postprandially.ResultsCompared to CON, HIE reduced postprandial glucose concentrations at 120–150 min in obese (p < 0.001) and lean men (p < 0.05), with greater reductions in obese than lean subjects at 120 (−27.0% vs. −8.3%), 135 (−31.9% vs. −15.7%), and 150 min (−21.8% vs. −10.6%). The total glucose area under the curve (AUC) for the testing period was lower with HIE than CON among obese men (p < 0.05), but not lean men (p > 0.05). We found moderate correlations between body mass and postprandial glucose changes (r = 0.39–0.44, p < 0.05), and between glucose AUC and body mass and fat free mass (r = 0.39–0.48, p < 0.05).ConclusionsOur findings suggest that HIE may act as a time-efficient lifestyle intervention strategy for improving obesity-related diabetes risk factors, and might play a role in primary diabetes prevention for the healthy but sedentary population. 相似文献