全文获取类型
收费全文 | 45301篇 |
免费 | 4625篇 |
国内免费 | 927篇 |
专业分类
耳鼻咽喉 | 315篇 |
儿科学 | 919篇 |
妇产科学 | 596篇 |
基础医学 | 3697篇 |
口腔科学 | 1517篇 |
临床医学 | 4347篇 |
内科学 | 5880篇 |
皮肤病学 | 496篇 |
神经病学 | 3495篇 |
特种医学 | 1441篇 |
外国民族医学 | 3篇 |
外科学 | 3523篇 |
综合类 | 4944篇 |
现状与发展 | 6篇 |
一般理论 | 2篇 |
预防医学 | 7826篇 |
眼科学 | 586篇 |
药学 | 3516篇 |
33篇 | |
中国医学 | 4492篇 |
肿瘤学 | 3219篇 |
出版年
2024年 | 164篇 |
2023年 | 1014篇 |
2022年 | 1472篇 |
2021年 | 1878篇 |
2020年 | 1821篇 |
2019年 | 1790篇 |
2018年 | 1778篇 |
2017年 | 1698篇 |
2016年 | 1567篇 |
2015年 | 1431篇 |
2014年 | 3291篇 |
2013年 | 3316篇 |
2012年 | 2632篇 |
2011年 | 2792篇 |
2010年 | 2165篇 |
2009年 | 2082篇 |
2008年 | 2321篇 |
2007年 | 2385篇 |
2006年 | 2118篇 |
2005年 | 1787篇 |
2004年 | 1479篇 |
2003年 | 1401篇 |
2002年 | 1108篇 |
2001年 | 1022篇 |
2000年 | 825篇 |
1999年 | 713篇 |
1998年 | 531篇 |
1997年 | 551篇 |
1996年 | 418篇 |
1995年 | 432篇 |
1994年 | 372篇 |
1993年 | 308篇 |
1992年 | 315篇 |
1991年 | 279篇 |
1990年 | 229篇 |
1989年 | 210篇 |
1988年 | 202篇 |
1987年 | 161篇 |
1986年 | 132篇 |
1985年 | 120篇 |
1984年 | 108篇 |
1983年 | 75篇 |
1982年 | 71篇 |
1981年 | 66篇 |
1980年 | 62篇 |
1979年 | 35篇 |
1978年 | 33篇 |
1977年 | 28篇 |
1976年 | 18篇 |
1975年 | 19篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
Yun Chen Na Wang Xiaolian Dong Jianfu Zhu Yue Chen Qingwu Jiang Chaowei Fu 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2021,31(8):2416-2425
Background and aimsSome amino acids (AAs) may be associated with type 2 diabetes (T2DM). This study aimed to determine the associations of individual AAs with the development of T2DM in rural Chinese adults.Methods and resultsA cohort study of 1199 individuals aged 18 years or older was conducted from 2006 to 2008 in a rural community of Deqing, China, a repeated survey was done in 2015 and data linkage with the electronic health records system was performed each year for identifying new T2DM cases. A high-performance liquid chromatography approach was used to measure the baseline serum concentrations of 15 AAs. Cox proportional hazards models were used to examine the associations between AAs and the risk of incident T2DM. A total of 98 new T2DM cases were identified during the follow-up of 12 years on average. Among 15 AAs, proline was associated with an increased risk of incident T2DM after adjusted for age, sex, body mass index, fasting plasma glucose, family history of T2DM, smoking status, alcohol use, and history of hypertension, the adjusted hazard ratio for 1-standard deviation increment was 1.20 (95% confidence interval: 1.00, 1.43). The association tended to be more marked in subjects younger than 60 years and overweight/obese subjects. Among participants without hypertension, proline and phenylalanine were associated with an increased risk of incident T2DM, while aspartic acid was associated with a decreased risk.ConclusionSerum proline was associated with the risk of incident T2DM in rural Chinese adults and might be a potential predictor. 相似文献
992.
993.
994.
Nul D Zambrano C Diaz A Ferrante D Varini S Soifer S Grancelli H Doval H;Grupo de Estudio de la Sobrevida en la Insuficiencia Cardiaca en Argentina 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》2005,19(2):125-134
Grupo de Estudio de la Sobrevida en la Insuficiencia Cardiaca en Argentina (GESICA) studied whether a standardized protocol for the initiation and titration of the β-blocker carvedilol in a multicenter, open-label program would optimize β-blocker use in heart failure (HF) patients. The program included: (1) the carvedilol initiation and titration period, and (2) long-term follow-up at 6 and 12 months. Of 1299 patients in the registry, 504 were excluded due to current therapy; of the remaining 795 eligible patients, 293 were excluded due to contraindications. Of the included patients with follow-up data (n = 316), 93.3% tolerated carvedilol initiation and 47.7% of the patients reached the target dose of 50 mg/day for a mean dose of 39 mg/day. Rates were comparable in the elderly (n = 83), of which 53% achieved a target dose for a mean dose of 43.08 mg/day. This protocol improved therapy rates and achieved target doses quickly (average of 4 visits). Concomitant medications did not have to be adjusted and there were low withdrawal rates (10%) and hospital admissions (7.2%) for HF. Patients were able to maintain carvedilol therapy at 6 and 12 months. These results indicate that a standardized titration protocol, as used in GESICA, for the initiation and titration of β-blockers is well tolerated and may improve β-blocker use in carefully selected heart failure patients.The study authors are members of the GESICA Steering Committee and Subcommittees 相似文献
995.
996.
Tasnime Akbaraly Claire Sexton Enikő Zsoldos Abda Mahmood Nicola Filippini Clarisse Kerleau Jean-Michel Verdier Marianna Virtanen Audrey Gabelle Klaus P. Ebmeier Mika Kivimaki 《The American journal of medicine》2018,131(11):1372-1381.e4
BACKGROUND
Diet quality is associated with brain aging outcomes. However, few studies have explored in humans the brain structures potentially affected by long-term diet quality. We examined whether cumulative average of the Alternative Healthy Eating Index 2010 (AHEI-2010) score during adult life (an 11-year exposure period) is associated with hippocampal volume.METHODS
Analyses were based on data from 459 participants of the Whitehall II imaging sub-study (mean age [standard deviation] (SD)?=?59.6 [5.3] years in 2002-2004, 19.2% women). Multimodal magnetic resonance imaging examination was performed at the end of follow-up (2015-2016). Structural images were acquired using a high-resolution 3-dimensional T1-weighted sequence and processed with Functional Magnetic Resonance Imaging of the Brain Software Library (FSL) tools. An automated model-based segmentation and registration tool was applied to extract hippocampal volumes.RESULTS
Higher AHEI-2010 cumulative average score (reflecting long-term healthy diet quality) was associated with a larger total hippocampal volume. For each 1 SD (SD?=?8.7 points) increment in AHEI-2010 score, an increase of 92.5 mm3 (standard error?=?42.0 mm3) in total hippocampal volume was observed. This association was independent of sociodemographic factors, smoking habits, physical activity, cardiometabolic health factors, cognitive impairment, and depressive symptoms, and was more pronounced in the left hippocampus than in the right hippocampus. Of the AHEI-2010 components, no or light alcohol consumption was independently associated with larger hippocampal volume.CONCLUSIONS
Higher long-term AHEI-2010 scores were associated with larger hippocampal volume. Accounting for the importance of hippocampal structures in several neuropsychiatric diseases, our findings reaffirm the need to consider adherence to healthy dietary recommendation in multi-interventional programs to promote healthy brain aging. 相似文献997.
Summary Serum-insulin levels were measured in 1770 subjects one hour after a 50 g glucose load. Multiple regression analyses reveal that a substantial proportion of the variability of log10 serum-insulin can be attributed to significant independent effect of blood-sugar, age, the food-interval, sex, parameters of body size, and scserum uric acid. Females have significantly higher levels of serum-insulin than males One-hour blood-sugar levels exceeding 160 nag/100 ml are associated with declining insulin levels. An independent association of increasing age with increasing serum-insulin is evident at 50 years and over. The findings provide strong support for the biological significance of serum-immunoreactive insulin.
Einfluß verschiedener Faktoren auf die Seruminsulinausschüttung bei einer Reihenuntersuchung
Zusammenfassung Die Seruminsulinspiegel 1 Std nach oraler Verabreichung von 50 g Glucose wurden bei 1770 Probanden bestimmt. Eine multiple Regressionsanalyse der Zehnerlogarithmuswerte für die Seruminsulinkonzentrationen ergab, daß ein beträchtlicher Teil der Variationsbreite durch signifikante und von einander unabhängige Einflüsse des Blutzuckers, des Alters, der Intervalle zwischen den Mahlzeiten, des Geschlechtes, des Körpergewichtes und der Harnsäure bedingt ist. Frauen wiesen significant höhere Insulinwerte als Männer auf. Häufig waren 1 Std Blutzuckerwerte über 160 mg% mit sinkenden Insulinspiegeln gekoppelt. Bei über 50 jährigen stiegen mit zunehmendem Alter auch die Insulinwerte an. Die Befunde stützen die Annahme, daß den immunologisch gemessenen Seruminsulinspiegeln biologische Bedeutung zukommt.
Facteurs déterminant la réponse de Vinsuline sérique dans un échantillon de population
Résumé Les taux d'insuline sérique ont été mesurés chez 1770 sujets une heure après une charge en glucose de 50 g. Des analyses de régression multiple révèlent qu'une proportion considérable de la variabilité du log10 de l'insuline sérique revient de façon significative aux effets indépendants entre eux de la glycémie, de l'âge, de l'intervalle entre les repas, du sexe, des paramètres de la taille corporelle et de l'acide urique sérique. Les femmes ont des niveaux d'insuline sérique significativement plus élevés que les hommes. Les taux de la glycémie une heure après, dépassant 160 mg/100 ml sont associés à une défaillance des taux d'insuline. Une association indépendante entre l'augmentation de l'âge et l'augmentation de l'insuline sérique est évidente à 50 ans et plus. Ces résultats apportent un argument solide pour l'importance biologique de l'insuline immunoréactive du sérum.相似文献
998.
Gorski TF Rosen L Lawrence S Helfrich D Reed JF 《Diseases of the colon and rectum》1999,42(11):1381-1387
PURPOSE: Colorectal surgery, a high-volume procedure, has been targeted for performance improvement to reduce length of stay. Specific postoperative quality indicators and readmission rates should be analyzed concomitantly to assure that adverse events are not associated with earlier discharge. METHODS: From July 1, 1990, to June 30, 1997, 1,218 consecutive patients who underwent transabdominal colorectal surgery were analyzed for length of stay, mortality, morbidity, and discharge disposition. Each patient was assigned an Admission Severity Group rating 0 to 4 using a hospital-based state-legislated software system (Atlas) to validate comparative performance internally and externally. Readmission data within 120 days of discharge were available for the last 678 consecutive patients from July 1, 1993, to June 30, 1997, using Lastword (computerized medical records). RESULTS: The annual frequencies of the 1,218 procedures were 173, 183, 175, 146, 167, 189, and 185, respectively, from July 1990 through June 1997. Severity distribution was 32 for Admission Severity Group 0, 517 for Admission Severity Group 1, 540 for Admission Severity Group 2, 128 for Admission Severity Group 3, and 1 for Admission Severity Group 4, with no annual difference (P=0.012). There was a significant reduction in total length of stay of 3.1 (12.9–9.8) days during the seven years (P=0.001). The overall operative mortality rate was 1.4 percent, and the morbidity was 2.6 percent, with no annual differences (P=0.655 andP=0.033, respectively). The disposition to home did not change (P=0.21). Of the 678 patients followed up for readmission, 100 (14.7 percent) were readmitted within 120 days, with no annual difference (P=0.302). CONCLUSION: Mortality, morbidity, disposition, and readmission rates were not affected by a decreased length of stay after colorectal surgery.Presented at the Research Forum at the meeting of The American Society of Colon and Rectal Surgeons, San Antonio, Texas, May 2 to 7, 1998. 相似文献
999.
1000.