全文获取类型
收费全文 | 136993篇 |
免费 | 7868篇 |
国内免费 | 783篇 |
专业分类
耳鼻咽喉 | 1366篇 |
儿科学 | 4324篇 |
妇产科学 | 3098篇 |
基础医学 | 19648篇 |
口腔科学 | 6572篇 |
临床医学 | 12072篇 |
内科学 | 30081篇 |
皮肤病学 | 3355篇 |
神经病学 | 12759篇 |
特种医学 | 3321篇 |
外国民族医学 | 3篇 |
外科学 | 13062篇 |
综合类 | 839篇 |
一般理论 | 55篇 |
预防医学 | 14015篇 |
眼科学 | 2120篇 |
药学 | 9537篇 |
中国医学 | 672篇 |
肿瘤学 | 8745篇 |
出版年
2024年 | 148篇 |
2023年 | 1289篇 |
2022年 | 2853篇 |
2021年 | 4719篇 |
2020年 | 3026篇 |
2019年 | 3977篇 |
2018年 | 4580篇 |
2017年 | 3491篇 |
2016年 | 3912篇 |
2015年 | 4364篇 |
2014年 | 5735篇 |
2013年 | 7355篇 |
2012年 | 11084篇 |
2011年 | 11679篇 |
2010年 | 6322篇 |
2009年 | 5243篇 |
2008年 | 9004篇 |
2007年 | 9007篇 |
2006年 | 8189篇 |
2005年 | 7515篇 |
2004年 | 6730篇 |
2003年 | 6037篇 |
2002年 | 5434篇 |
2001年 | 1258篇 |
2000年 | 1138篇 |
1999年 | 1184篇 |
1998年 | 1027篇 |
1997年 | 792篇 |
1996年 | 702篇 |
1995年 | 588篇 |
1994年 | 554篇 |
1993年 | 453篇 |
1992年 | 568篇 |
1991年 | 449篇 |
1990年 | 461篇 |
1989年 | 438篇 |
1988年 | 418篇 |
1987年 | 321篇 |
1986年 | 339篇 |
1985年 | 277篇 |
1984年 | 264篇 |
1983年 | 234篇 |
1982年 | 214篇 |
1981年 | 170篇 |
1980年 | 173篇 |
1979年 | 184篇 |
1978年 | 168篇 |
1977年 | 131篇 |
1974年 | 133篇 |
1973年 | 121篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
32.
Betsy D. Kennard Susan G. Silva Simon Tonev Paul Rohde Jennifer L. Hughes Benedetto Vitiello Christopher J. Kratochvil John F. Curry Graham J. Emslie Mark Reinecke John March 《Journal of the American Academy of Child and Adolescent Psychiatry》2009,48(2):186-195
ObjectiveWe examine remission rate probabilities, recovery rates, and residual symptoms across 36 weeks in the Treatment for Adolescents with Depression Study (TADS).MethodThe TADS, a multisite clinical trial, randomized 439 adolescents with major depressive disorder to 12 weeks of treatment with fluoxetine, cognitive–behavioral therapy, their combination, or pill placebo. The pill placebo group, treated openly after week 12, was not included in the subsequent analyses. Treatment differences in remission rates and probabilities of remission over time are compared. Recovery rates in remitters at weeks 12 (acute phase remitters) and 18 (continuation phase remitters) are summarized. We also examined whether residual symptoms at the end of 12 weeks of acute treatment predicted later remission.ResultsAt week 36, the estimated remission rates for intention-to-treat cases were as follows: combination, 60%; fluoxetine, 55%; cognitive–behavioral therapy, 64%; and overall, 60%. Paired comparisons reveal that, at week 24, all active treatments converge on remission outcomes. The recovery rate at week 36 was 65% for acute phase remitters and 71% for continuation phase remitters, with no significant between-treatment differences in recovery rates. Residual symptoms at the end of acute treatment predicted failure to achieve remission at weeks 18 and 36.ConclusionsMost depressed adolescents in all three treatment modalities achieved remission at the end of 9 months of treatment. 相似文献
33.
34.
35.
Lucio Lucchin Amleto D’Amicis Maria Gabriella Gentile Nino Carlo Battistini Maria Antonia Fusco Augusta Palmo Maurizio Muscaritoli Franco Contaldo Emanuele Cereda 《Mediterranean journal of nutrition and metabolism》2009,2(3):171-179
Aim and methods Nutrition, unhealthy lifestyles and cancer appear to be strictly related, but few authors have analysed the interest in dietary
information of cancer patients and their families. This survey was conducted in the Veneto area (Italy) to investigate the
concern of cancer patients and their family members about diet as a health tool before and after diagnosis of cancer.
Results Seven hundred and four questionnaires were collected: 380 from cancer patients and 324 from family members of cancer subjects.
Breast cancer (BC) was the most frequent disease for patients (61.8%) as well as families (26.5%). Generally, the importance
of having precise diet information after diagnosis is recognised by 40.3% of patients, with significant differences between
the various types of cancer: gastric and colon/rectum cancer (GCC) patients were more concerned than BC women about precise
information concerning a diet to follow immediately after diagnosis (p = 0.000, ODs = 3.10, CI 1.68–5.71) or during treatments (p = 0.001, ODs = 2.67, CI 1.46–4.89). The nutritional information is supplied to patients in 34% of cases and to relatives
in 30.3%, often from non-medical sources. In total healthcare workers (family doctor, oncologist, surgeon, dietician) represented
the exclusive source of dietary information for 24.9% of patients and 22.9% of family members. Diet after diagnosis changes
in 69.1% of GCC patients and in 39.2% of BC women. Relatives, particularly women, report difficulties preparing patients’
meals in 30.7% of cases, changes in the eating habits of the entire family in 29.9% and discontent connected with patients
diet in 13.9%. The concern about proper nutrition after diagnosis increases more in GCC subjects (p < 0.025) when compared to BC subjects and in patients with more recent diagnosis (p < 0.041) when compared with patients with diagnosis >5 years ago, while in family members the interest in diet after diagnosis
increases more in women than in men (p < 0.030) without other differences regarding the degree of relationship, type of cancer or diagnosis time. Relatives (92.7%)
have more interest in nutritional education than patients (74.9%). Cancer patients <65 years were more interested in educational
initiatives concerning nutrition (p = 0.000, ODs = 4.46, CI 2.6–7.4) than older patients (>65 years) and female subjects were more concerned than male patients
(p = 0.008, ODs = 2.11, CI 1.2–3.6).
Conclusions The interest in the dietary knowledge and in educational initiatives concerning nutrition is high in cancer patients and their
relatives, although it decreases with the age. The poor attention paid to nutrition of cancer patients by various healthcare
workers deserves consideration, since the psychophysical wellbeing and perhaps also survival of cancer patients can be improved
by correct dietary management, as well as, naturally, by the principal treatments themselves. 相似文献
36.
Henyse G V Silva Rosangela P Tórtora Maria Lucia F Farias 《Gynecological endocrinology》2005,21(3):174-179
To evaluate the impact of pregnancy on bone, we studied bone turnover at the first (T1) and third (T3) trimester of gestation in 58 adolescents and 28 healthy adolescents who had never been pregnant. Total body (TB) and lumbar spine (LS) bone mineral density (BMD) and body composition were evaluated by dual-energy X-ray absorptiometry in all control patients (C) and after parturition in 28 pregnant patients (G). Paired and unpaired t tests, Mann-Whitney and Pearson correlation tests were used. Bone turnover markers were above the reference range for adult women in more than 80% of the adolescents, with no difference between C and G patients at T1. Increase in urinary N-telopeptide crosslinks of type I collagen and serum bone-specific alkaline phosphatase, markers of bone turnover, was seen during pregnancy ( p < 0.0001). Body composition did not differ between groups, but LS BMD, percentage of expected LS BMD, LS Z-score, percentage of expected TB BMD and TB Z-score were lower in G than C patients ( p < 0.05). TB BMD was positively correlated with LS BMD (r2 = 0.52). The inverse correlations between bone markers and LS BMD suggest that the increased bone turnover during pregnancy probably explains the low bone density after parturition. The impact on future peak bone mass must be studied. 相似文献
37.
38.
We found multimolecular antigenic mimicry of arthritogenic autoantigens and peptides from several other “self” or foreign antigens sharing amino acid sequence homologies. Many of these new mimotopes induced arthritis and/or uveitis upon immunization in Lewis rats, indicating a role for multiple antigens in the initiation of a certain autoimmune disease. 相似文献
39.
Frequency of and risk factors for allergy in primary school children: results of a population survey 总被引:1,自引:0,他引:1
Anna Maria Angioni Giovanni Fanciulli Carlo Corchia † 《Paediatric and perinatal epidemiology》1989,3(3):248-255
During May 1986, a survey to assess the frequency of allergic disorders was conducted among primary school children of Alghero, Sardinia, using a structured self-administered questionnaire. The following problems were investigated: allergic conjunctivitis, asthma, wheezing, allergic rhinitis, urticaria and eczema. Of the original 1823 questionnaires distributed, 1961 (92.8%) were completed by parents and returned. Overall, 238 children (14.1%) were reported to have shown at least one episode of one or more of the above and were regarded as 'allergic'. Among the potential risk factors investigated, statistically significant differences (P less than 0.05) between allergic and non-allergic children were only found for history of allergy in at least one parent (odds ratio, OR = 2.2) and exposure to passive smoking (OR = 1.4). 相似文献
40.
A C Da Rosa B Kemp T Paiva F H Lopes da Silva H A Kamphuisen 《Electroencephalography and clinical neurophysiology》1991,78(1):71-79
A model of sleep phasic events such as vertex waves, K complexes, delta waves and sleep spindles is proposed. It consists of feedback loops that are driven by white noise (simulating tonic delta and sigma activity) and by isolated random impulses, simulating vertex waves or K complexes, depending on the background tonic activity. A model-based method for the detection of sleep phasic events was implemented in a personal computer. Its performance was investigated using simulated and real whole-night EEG signals. The method was able to detect K complexes and vertex waves in a reliable way in spite of their variable shapes and in the presence of a variety of background activities. The detector appears to have superior performance to those so far reported in the literature. The performance of the detector was also compared to that of an electroencephalographer using normal sleep EEG records of 8 h duration from 6 subjects. The performance was satisfactory both in terms of accuracy and reliability. The problem of detecting K complexes in stages 3 and 4 of sleep is discussed. 相似文献