全文获取类型
收费全文 | 38495篇 |
免费 | 2392篇 |
国内免费 | 433篇 |
专业分类
耳鼻咽喉 | 767篇 |
儿科学 | 498篇 |
妇产科学 | 558篇 |
基础医学 | 6409篇 |
口腔科学 | 685篇 |
临床医学 | 3146篇 |
内科学 | 7537篇 |
皮肤病学 | 1529篇 |
神经病学 | 2979篇 |
特种医学 | 2371篇 |
外科学 | 5135篇 |
综合类 | 133篇 |
一般理论 | 13篇 |
预防医学 | 1310篇 |
眼科学 | 830篇 |
药学 | 3702篇 |
中国医学 | 517篇 |
肿瘤学 | 3201篇 |
出版年
2024年 | 22篇 |
2023年 | 343篇 |
2022年 | 978篇 |
2021年 | 1537篇 |
2020年 | 767篇 |
2019年 | 1058篇 |
2018年 | 1247篇 |
2017年 | 1012篇 |
2016年 | 1481篇 |
2015年 | 1999篇 |
2014年 | 2248篇 |
2013年 | 2528篇 |
2012年 | 3713篇 |
2011年 | 3503篇 |
2010年 | 2097篇 |
2009年 | 1637篇 |
2008年 | 2377篇 |
2007年 | 2158篇 |
2006年 | 1993篇 |
2005年 | 1753篇 |
2004年 | 1410篇 |
2003年 | 1242篇 |
2002年 | 1045篇 |
2001年 | 513篇 |
2000年 | 455篇 |
1999年 | 390篇 |
1998年 | 199篇 |
1997年 | 148篇 |
1996年 | 127篇 |
1995年 | 110篇 |
1994年 | 99篇 |
1993年 | 81篇 |
1992年 | 111篇 |
1991年 | 110篇 |
1990年 | 83篇 |
1989年 | 82篇 |
1988年 | 83篇 |
1987年 | 74篇 |
1986年 | 57篇 |
1985年 | 54篇 |
1984年 | 46篇 |
1983年 | 42篇 |
1982年 | 31篇 |
1981年 | 24篇 |
1980年 | 24篇 |
1979年 | 38篇 |
1978年 | 20篇 |
1976年 | 19篇 |
1972年 | 17篇 |
1969年 | 17篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
H Ando H Yasui H Kado K Yonenaga T Shin H Iwao H Sunagawa S Honda 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1990,38(4):618-624
From October, 1980, to June, 1987, thirty-eight infants less than one year old underwent correction for total anomalous pulmonary venous connection (TAPVC). Overall operative mortality and late mortality were 13% and 6%, respectively. Residual pulmonary hypertension was noted in 4 patients: three had pulmonary venous obstruction at the site of atrial anastomosis (PVOA) and one had supracardiac (Ia) lesion left after repair of mixed type (IV: Ia + III) of TAPVC. Two late deaths occurred in these with PVOA. Twenty-two patients with supracardiac (I) or infracardiac (III) TAPVC were divided into three groups according to the technical development in atrial anastomosis: the large anastomosis in which venous incision reached into at least one pulmonary vein beyond common pulmonary vein and the continuous running suture were used in 10 patients (group 1), the appropriate size of anastomosis in which venous incision limited within the common pulmonary vein and the continuous running suture used in 4 patients (group 2), and the appropriate size of anastomosis and the interrupted suture in 8 patients (group 3). PVOA were 3 (33%) in group 1, but 0 (0%) in group 2 and 3. Two late death occurred all in group 1 with PVOA. Cardiopulmonary bypass time and aortic clamp time in group 3 were 91 min and 74 min respectively, which did not become longer than those in both group 1 and group 2. Interrupted suture technique does not make operating time longer than continuous running suture one. PVOA is one of the important factors predicting late operative result.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
22.
23.
Heterotopic heart transplantation: a radiographic review 总被引:1,自引:0,他引:1
C K Adey P H Nath B Soto M S Shin M Schwartz A E Epstein J K Kirklin 《Radiographics》1987,7(1):151-160
Heterotopic heart transplantation can be performed in the presence of high pulmonary vascular resistance. The authors call attention to a rare, but potentially life-saving procedure. 相似文献
24.
Kazuhiko Suzuki Hiroshi Tanaka Satoshi Kaneko Motoi Nishi Shin Teramoto Susumu Itoh Shosaku Abe 《The Journal of asthma》2003,40(3):243-250
The relation between smoking and risk of asthma has been well-examined; however little attention has been paid to the correlation between smoking and asthma symptoms. The aims of this study were to examine respiratory symptoms in asthmatics with a highly prevalent use of inhaled corticosteroid (ICS) and to assess the effects of smoking and its cessation. A cross-sectional study of pulmonologist-based 3197 asthmatics (men 45.2%, ages 20-97) was performed using a questionnaire about smoking habits, the incidence and frequency of symptoms (sputum, cough and wheezing, night symptoms, and shortness of breath), physical activity interference, and medication. Although 81.4% of the patients used ICS according to the international guideline, 14.9% had activity interference, and daily symptoms remained in 43.3%. At the time of the questionnaire, 21.6% were current and 25.1% were ex-smokers. In multiple logistic regression analysis, the factors of significance (p < 0.0001) were (1) smoking; for all four symptoms, (2) age and duration of asthma; for shortness of breath. Current smokers were at a risk of sputum (age-adjusted odds ratio 2.32 [95% confidence interval 1.73-3.11]; 2.09 [1.57-2.79]), of cough and wheezing (2.38 [1.81-3.14]; 1.78 [1.35-2.36]), of night symptoms (1.95 [1.41-2.60]; 1.47 [1.09-1.98]), and of shortness of breath (1.70 [1.26-2.28]; 1.30 [0.97-1.75]) in men and women, respectively. These ratios in ex-smokers decreased to the level similar to nonsmokers. Although 81.4% of asthmatic patients used ICS, 43.3% complained of daily respiratory symptoms, especially sputum. It is suggested that the effects of ICS on asthma symptoms may be interfered with by smoking and therefore more emphasis should be placed on cessation of smoking. 相似文献
25.
26.
3-Monochloro-1,2-propanediol (MCPD) is a well-known by-product of acid-hydrolyzed soy sauce during its manufacturing process. MCPD has been reported genotoxic in vitro, and reproductive toxicity and carcinogenicity in rats. To evaluate the immunomodulatory effect of MCPD on murine splenocyte and macrophage in vitro, we investigated splenocyte blastogenesis by concanavalin A (Con A), anti-CD3, and lipopolyssacharide (LPS), the production of cytokines from splenocyte, and the activity of mouse peritoneal macrophages. There was a significant decrease in lymphocyte blastogenesis to Con A or anti-CD3 at subtoxic dose of MCPD. A significant decrease in splenocyte blastogenesis to LPS was also observed. The production level of interferon (IFN)-gamma on splenocyte culture with Con A was significantly reduced at the higher concentration than 1.0mM of MCPD. The levels of interleukin (IL)-4 and IL-10 were also decreased at high concentrations of MCPD. There was a significant decrease in production of nitric oxide (NO) by peritoneal macrophages treated with MCPD. MCPD also inhibits tumor necrosis factor (TNF)-alpha production of stimulated macrophages. These results indicate that MCPD might be able to reduce the functionality of lymphocytes and peritoneal macrophages in vitro. 相似文献
27.
28.
29.
Jun Suk Huh Sang Keun Park Jun Jae Shin Tae Hong Kim 《Journal of Korean Neurosurgical Society》2007,42(4):342-345
The azygos anterior cerebral artery, a rare anomaly in the circle of Willis in which only a single vessel supplies the medial aspects of both anterior cerebral hemispheres, is closely associated with saccular aneurysms. We present three cases of azygos anterior cerebral artery aneurysms among the 781 cerebral aneurysms surgically treated at our institution in an 11-year period. These three cases all involved elderly women who presented with subarachnoid hemorrhage. Conventional cerebral angiography and CT angiography revealed small saccular aneurysms at the distal ends of the azygos anterior cerebral arteries. These aneurysms were clipped successfully using a bifrontal interhemispheric approach. Hence, the pathogenesis of these particular aneurysms relating to hemodynamic change, associated anomalies, and surgical pitfalls is discussed with review of literature. 相似文献
30.
Treatment of congenital cystic adenomatoid malformation-does resection in the early postnatal period increase surgical risk? 总被引:1,自引:0,他引:1
Young Tae Kim Jun Sung Kim June Dong Park Chang Hyun Kang Sook Whan Sung Joo Hyun Kim 《European journal of cardio-thoracic surgery》2005,27(4):658-661
OBJECTIVE: The recent development of fetal ultrasonography has allowed for an increasing number of prenatal diagnoses for congenital cystic adenomatoid malformation (CCAM). However, the appropriate surgical timing of these patients has not been studied as of yet. The aim of this study is to suggest a safe strategy for the treatment of CCAM by identifying the relationship between the timing of surgery and postoperative outcome. METHODS: Between 1987 and 2003, 40 patients (28 males, 12 females) underwent surgical resection for CCAM. The mean age was 38.6+/-9.1 (2 days-13 years) months. CCAM was diagnosed by prenatal ultrasonography in eight patients. Early operations were performed in four out of the eight. Operation was deferred until 2-12 months of age for the remaining four patients. RESULTS: Type I CCAM was found in 20 patients, type II in 20 and no patient exhibited type III. Five patients had associated pectus excavatum anomaly. There were no cases of operative mortality. Seventeen minor postoperative complications developed in 16 patients (40.0%): prolonged chest tube drain in 10, wound infection in 4, and 1 case of pneumonia, empyema and pleural space, respectively. The average hospital stay was 11.8 (6-29) days. During the mean follow-up period of 67.5 months, one patient died of accidental aspiration 7 months after operation during the postoperative recovery course of Ravich operation for pectus excavatum. The remaining patients reported doing well with normal physical activity. All five patients who underwent surgery at the age of under 1 month did not exhibit increased postoperative morbidity. CONCLUSIONS: We concluded that surgery for CCAM could be safely performed in all age groups with satisfactory long-term outcomes. It is suggested that early elective surgical correction can be recommended for a patient whose diagnosis was made in utero. 相似文献