全文获取类型
收费全文 | 27647篇 |
免费 | 2463篇 |
国内免费 | 545篇 |
专业分类
耳鼻咽喉 | 159篇 |
儿科学 | 620篇 |
妇产科学 | 650篇 |
基础医学 | 3556篇 |
口腔科学 | 794篇 |
临床医学 | 2310篇 |
内科学 | 3741篇 |
皮肤病学 | 352篇 |
神经病学 | 1699篇 |
特种医学 | 763篇 |
外国民族医学 | 8篇 |
外科学 | 3257篇 |
综合类 | 3556篇 |
现状与发展 | 2篇 |
预防医学 | 1638篇 |
眼科学 | 237篇 |
药学 | 2773篇 |
15篇 | |
中国医学 | 1468篇 |
肿瘤学 | 3057篇 |
出版年
2023年 | 332篇 |
2022年 | 504篇 |
2021年 | 913篇 |
2020年 | 907篇 |
2019年 | 933篇 |
2018年 | 923篇 |
2017年 | 927篇 |
2016年 | 1017篇 |
2015年 | 1014篇 |
2014年 | 1790篇 |
2013年 | 2016篇 |
2012年 | 1546篇 |
2011年 | 1883篇 |
2010年 | 1301篇 |
2009年 | 1316篇 |
2008年 | 1270篇 |
2007年 | 1320篇 |
2006年 | 1203篇 |
2005年 | 1057篇 |
2004年 | 986篇 |
2003年 | 825篇 |
2002年 | 649篇 |
2001年 | 643篇 |
2000年 | 545篇 |
1999年 | 481篇 |
1998年 | 401篇 |
1997年 | 386篇 |
1996年 | 317篇 |
1995年 | 312篇 |
1994年 | 279篇 |
1993年 | 225篇 |
1992年 | 194篇 |
1991年 | 164篇 |
1990年 | 181篇 |
1989年 | 128篇 |
1988年 | 115篇 |
1987年 | 113篇 |
1986年 | 93篇 |
1985年 | 167篇 |
1984年 | 213篇 |
1983年 | 110篇 |
1982年 | 161篇 |
1981年 | 148篇 |
1980年 | 112篇 |
1979年 | 97篇 |
1978年 | 77篇 |
1977年 | 57篇 |
1976年 | 65篇 |
1975年 | 60篇 |
1974年 | 60篇 |
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
81.
目的:明确氟对人牙乳头细胞合成 I型胶原的影响。 方法:对人牙乳头细胞进行体外培养 ,分别给予0 .0、0 .2× 10 - 6、1.0× 10 - 6、5 .0× 10 - 6、2 5 .0× 10 - 6 g/ L 氟处理 ,采用免疫细胞化学方法染色 ,图象分析氟对细胞合成 I型胶原的影响。 结果:I型胶原在对照组和 4种氟浓度处理组细胞表达均为阳性。图象分析结果表明 ,4种氟浓度对体外培养的人牙乳头细胞合成 I型胶原量与对照组相比差异无统计学意义 (P>0 .0 5 )。结论:过量氟对牙本质基质 型胶原的影响可能不是通过影响成牙本质细胞内合成实现的 相似文献
82.
本文报告胰岛细胞脑内移植治疗I型糖尿病共3例,分别经过3个月、4个月、6个月的临床观察,其临床症状明显改善或消失,空腹血糖由移植前平均12.38mmol/L下降至7.77mmol/L;3例患者普通胰岛素用量平均每日62.3~u,移植后第21~30天均完全停用胰岛素,其中1例已持续撤离胰岛素治疗达5个月。观察结果提示:胰岛移植物在患者的脑内成活,并具有良好的内分泌功能。 相似文献
83.
Albers LL 《Journal of Midwifery & Women's Health》2007,52(3):207-215
The active phase of first stage labor is generally defined as the period between 3 cm to 4 cm to complete cervical dilatation, in the presence of regular uterine contractions. Most women will experience this portion of labor within hospital obstetric units, where care commonly features restriction to bed, electronic fetal monitoring, early treatment of "slow" labors, and few pain management options beyond epidurals and narcotics. However, the available evidence on appropriate care for healthy childbearing women favors activity in labor, intermittent auscultation, patience from caregivers, and nonpharmacologic methods of pain relief. This article reviews the evidence for care practices that support physiologic labor. Modifying intrapartum care to reflect current evidence will improve women's health, and will require a multilevel approach and consistent midwifery demonstration of the model. 相似文献
84.
J. Scott Tonigan 《Alcoholism, clinical and experimental research》2007,31(S3):55s-56s
The statistical search for mechanisms of change involves multiple inferential tests, ones that generally follow a fixed sequence designed to demonstrate mediation. While there are several popular approaches to conducting such tests, e.g., SEM and MRA, the inflated Type I error rate problem associated with conducting these tests has received little, if any, attention. This paper offers 2 solutions to avoid committing Type I errors associated with mediational tests. Most straightforward, investigators may choose to use a Bonferroni adjustment. In contrast, a design-based approach can be used that tests rival explanations for the observed effects. Examples drawn from addiction research are provided. 相似文献
85.
New sonographic techniques for the diagnosis and treatment of hepatocellular carcinoma 总被引:1,自引:0,他引:1
Masatoshi Kudo 《Hepatology research》2007,37(S2):S193-S199
Ultrasound (US) contrast agents such as Levovist and Sonazoid are now commercially available in Japan. Innovative contrast agents and ultrasound technologies have dramatically changed both diagnostic and treatment strategies for hepatocellular carcinoma (HCC). Contrast-enhanced US is extremely useful in the differential diagnosis of hepatic tumors as well as in evaluation of post-treatment response of HCC after lipiodol transarterial chemoembolization and radio frequency ablation. Harmonic US sensitively detects residual cancer cells in HCC patients after treatment, to facilitate accurate guidance for needle insertion for US monitoring; no other imaging modalities, including computed tomography (CT) or magnetic resonance imaging (MRI), have such capability. In 2005, the breakthrough technology of pure arterial phase imaging, which depicts only intranodular arterial accumulated maximum intensity projection images, was developed from advanced raw data storing and accumulation technologies. This technique can clearly identify whether blood supplyin the tumor is of arterial or portal origin, to facilitate the non-invasive characterization of nodular lesions associated with liver cirrhosis. Again, CT or MRI do not have such capabilities. This innovative technique can help differentiate premalignant lesions from overt HCC. Concurrent real-time imaging of multi-detector CT and US, known as real-time virtual sonography, has recently become available. This technique greatly facilitates the treatment guidance for HCC. These newly introduced sonographic techniques are dramatically changing the diagnostic and therapeutic strategies for HCC, which are expected to improve the prognosis of HCC patients. 相似文献
86.
目的:研究中国安氏Ⅰ类错成人与美国安氏Ⅰ类错白人牙颌颅面形态结构的差异。方法:从西安市11所大学2098名新生中选取符合标准的101名(男53名、女48名)安氏Ⅰ类错样本。拍摄头颅定位X线片,用第四军医大学口腔医学院头影测量软件测量,用Alabama分析法与美国安氏Ⅰ类错白人颅颌面测量结果进行比较分析。结果:中国西安地区安氏Ⅰ类错成人上下颌突度大,面型较突;平面倾斜度、上下中切牙倾斜度及下中切牙至NB线距均较大;Y轴相对SN平面夹角增大,生长方向为后下。结论:与美国安氏Ⅰ类错白人比较,中国西安地区安氏Ⅰ类错成人颅面结构呈现颌骨突度大、下切牙唇倾及下颌趋向后下等特征。 相似文献
87.
目的:探讨肛裂疼痛的治疗效果及安全性。方法:将80例患者分为两组,治疗组采用黏膜保护剂太宁栓,对照组选用马应龙麝香痔疮膏。结果:治疗后太宁栓组疼痛、出血、瘙痒、水肿糜烂的减轻程度明显优于对照组(P〈0.05)。结论:太宁栓具有良好的止痛作用,临床效果明显,安全性高。 相似文献
88.
Kulbir S. Walia MD ; Daniel E. Muser MD ; Shariq S. Raza MD ; Tricia Griech MSPT ; Yasin N. Khan MD 《Pain practice》2004,4(4):303-306
Abstract: We present a case of a 13-year-old boy who developed signs and symptoms of neuropathic pain/early Complex Regional Pain Syndrome (CRPS) Type I, formerly known as Reflex Sympathetic Dystrophy (RSD), after spraining his ankle while wrestling. Aggressive pain control, using medications and sympatholytic blocks, with physical therapy and rehabilitation, led to the resolution of his painful condition. This prevented the disease from possibly progressing to a full-blown case of CRPS I (RSD) that is very challenging to treat. 相似文献
89.
Padmaja Yalamanchili Eric Wexler Megan Hayes Ming Yu Jody Bozek Mikhail Kagan Heike S. Radeke Michael Azure Ajay Purohit David S. Casebier Simon P. Robinson 《Journal of nuclear cardiology》2007,14(6):782-788
Background
BMS-747158-02 is a novel fluorine 18-labeled pyridazinone derivative designed for cardiac imaging. The uptake and retention
mechanisms of F-18 BMS-747158-02 in cardiac myocytes were studied in vitro, and the biodistribution of F-18 BMS-747158-02
was studied in vivo in mice.
Methods and Results
Fluorine 19 BMS-747158-01 inhibited mitochondrial complex I (MC-I) in bovine heart submitochondrial particles with an IC50 of 16.6±3 nmol/L that was comparable to the reference inhibitors of MC-1, rotenone, pyridaben, and deguelin (IC50 of 18.2±6.7 nmol/L, 19.8±2.6 nmol/L, and 23.1±1.5 nmol/L, respectively). F-18 BMS-747158-02 had high uptake in monolayers
of neonatal rat cardiomyocytes (10.3%±0.7% of incubated drug at 60 minutes) that was inhibited by 200 nmol/L of rotenone (91%±2%)
and deguelin (89%±3%). In contrast, an inactive pyridaben analog, P-0 (IC50 value>4 μmol/L in MC-1 assay), did not inhibit the binding of F-18 BMS-747158-02 in cardiomyocytes. Uptake and washout kinetics
for F-18 BMS-747158-02 in rat cardiomyocytes indicated that the time to half-maximal (t1/2) uptake was very rapid (approximately 35 seconds), and washout t1/2 for efflux of F-18 BMS-747158-02 was greater than 120 minutes. In vivo biodistribution studies in mice showed that F-18 BMS-747158-02
had substatial myocardial uptake (9.5%±0.5% of injected dose per gram) at 60 minutes and heart-to-lung and heart-to-liver
ratios of 14.1±2.5 and 8.3±0.5, respectively. Positron emission tomography imaging in the mouse allowed clear cardiac visualization
and demonstrated sustained myocardial uptake through 55 minutes.
Conclusions
F-18 BMS-747158-02 is a novel positron emission tomography cardiac tracer targeting MC-I in cardiomyocytes with rapid uptake
and slow washout. These characteristics allow fast and sustained accumulation in the heart. 相似文献
90.
杨永康 《中国烧伤创疡杂志》2006,18(3):223-225
目的:观察美宝湿润烧伤膏在血栓性外痔和陈旧性肛裂切除术后治疗中的疗效。方法:术毕用MEBO纱布条填塞伤口,术后24小时取出纱布条,以后用MEBO涂于伤口内,每日2次,直至痊愈。结果:48例患者无术后伤口疼痛、出血、感染及肛门狭窄。伤口愈合时间短,治愈率高。结论:美宝湿润烧伤膏是血栓性外痔、陈旧性肛裂切除术后良好的局部治疗药物。 相似文献