全文获取类型
收费全文 | 6851篇 |
免费 | 453篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 83篇 |
儿科学 | 211篇 |
妇产科学 | 201篇 |
基础医学 | 968篇 |
口腔科学 | 191篇 |
临床医学 | 601篇 |
内科学 | 1435篇 |
皮肤病学 | 85篇 |
神经病学 | 996篇 |
特种医学 | 304篇 |
外国民族医学 | 1篇 |
外科学 | 872篇 |
综合类 | 89篇 |
一般理论 | 3篇 |
预防医学 | 391篇 |
眼科学 | 144篇 |
药学 | 311篇 |
中国医学 | 4篇 |
肿瘤学 | 419篇 |
出版年
2022年 | 50篇 |
2021年 | 109篇 |
2020年 | 57篇 |
2019年 | 99篇 |
2018年 | 130篇 |
2017年 | 107篇 |
2016年 | 119篇 |
2015年 | 118篇 |
2014年 | 163篇 |
2013年 | 232篇 |
2012年 | 286篇 |
2011年 | 305篇 |
2010年 | 205篇 |
2009年 | 160篇 |
2008年 | 307篇 |
2007年 | 289篇 |
2006年 | 272篇 |
2005年 | 308篇 |
2004年 | 253篇 |
2003年 | 284篇 |
2002年 | 248篇 |
2001年 | 157篇 |
2000年 | 184篇 |
1999年 | 150篇 |
1998年 | 65篇 |
1997年 | 62篇 |
1996年 | 66篇 |
1995年 | 48篇 |
1993年 | 54篇 |
1992年 | 143篇 |
1991年 | 146篇 |
1990年 | 119篇 |
1989年 | 123篇 |
1988年 | 90篇 |
1987年 | 107篇 |
1986年 | 97篇 |
1985年 | 99篇 |
1984年 | 78篇 |
1983年 | 73篇 |
1982年 | 74篇 |
1981年 | 64篇 |
1980年 | 47篇 |
1979年 | 74篇 |
1978年 | 56篇 |
1977年 | 66篇 |
1976年 | 52篇 |
1975年 | 68篇 |
1974年 | 49篇 |
1973年 | 52篇 |
1972年 | 55篇 |
排序方式: 共有7309条查询结果,搜索用时 17 毫秒
1.
2.
3.
Steven V Koenen Anjoke J M Huisjes Jules Dings Yolanda van der Graaf Gerard H A Visser Hein W Bruinse 《The journal of maternal-fetal & neonatal medicine》2006,19(2):93-99
OBJECTIVE: To determine if there is a diurnal pattern in the clinical symptoms of HELLP (Hemolysis, Elevated Liver enzymes, Low Platelets) syndrome. STUDY DESIGN: A retrospective study was performed in 134 pregnancies complicated by HELLP syndrome. The medical records were reviewed to describe each HELLP episode. Time of day was divided into three periods, day, evening, and night. The following parameters were categorized according to the time of day: onset of symptoms, consultation by the doctor, initial blood sampling, diagnosis and decrease of symptoms. Biochemical parameters at clinical presentation and consecutive changes within 24 h were recorded. RESULTS: In 65 pregnancies 77 HELLP episodes were well documented. Times of onset of symptoms and consultation by the doctor were significantly higher during the evening and night (p < 0.001), whereas times of diagnosis and decrease of symptoms occurred significantly more during the day (p < 0.001). In only 49.3% of the cases were diagnostic laboratory criteria met at clinical presentation. This was mainly due to platelet values in excess of 100 x 10(9)/l. Several hours later (median 8 h, range 2-23) the decrease in platelets occurred. CONCLUSIONS: A diurnal pattern exists in the clinical symptoms of HELLP syndrome that is characterized by an exacerbation during the night and recovery during the day. There is a considerable delay between the onset of symptoms and the fulfillment of diagnostic laboratory criteria. 相似文献
4.
S C Chua A W Brown J Kim K L Hennessey R L Leibel J Hirsch 《Brain research. Molecular brain research》1991,11(3-4):291-299
We have used a novel method to identify genes expressed in the hypothalamus which may be potentially involved in controlling food intake and energy metabolism. We assumed that food deprivation, a powerful stimulus of food intake, would stimulate the activity of neural pathways involved in feeding behavior which should be reflected in an increase in the synthesis of any relevant neuropeptide and its messenger RNA. A study of 5 neuropeptides in 5 strains of mice has identified neuropeptide Y (NPY) as a gene whose expression in the hypothalamus is controlled by nutritional status, suggesting that hypothalamic NPY neurons are a link in the neural network regulating feeding behavior and energy metabolism. In addition, we have studied the effect of the diabetes mutation on neuropeptide gene expression during fasting and refeeding. Our findings suggest that abnormal NPY and enkephalin gene expression in the hypothalamus may be two important determinants of the expression of the diabetes mutation. 相似文献
5.
6.
A multiply injured patient’s airway is primarily secured with a laryngeal tube by the responding EMS. For helicopter transfer the flight physician decides not to intubate the patient’s trachea. Mechanical ventilation was performed without complications. 相似文献
7.
The appearance of an acute effusion in a well-pneumatized temporal bone directs attention to the nasopharynx and skull base. Two patients are described in whom dehiscence of the temporomandibular joint allowed herniation of the contents of the joint posteromedically, where they obstructed the middle ear entrance of the eustachian tube, the protympanum. This is, to the authors' knowledge, a previously unreported cause of an acute middle ear and mastoid effusion. 相似文献
8.
Dr. S. Eggstein MD G. Manthey MT T. Hirsch PhD F. Baas MA B. U. V. Specht MD E. H. Farthmann MD 《Digestive diseases and sciences》1996,41(6):1069-1075
Epidermal growth factor receptors (EGFR) andras mutations are known to play a significant role in controlling cell growth and tumor promotion. Both of them transmit mitogenic signals to the nucleus by activation of Raf-1 kinase. In this study, the expression of EGFR and mutant Ras proteins, and, for the first time, the expression, phosphorylation and kinase activity of Raf-1 kinase have been determined in paired samples of colorectal cancer and mucosa. The tumor and mucosa samples did not differ significantly with regard to Raf-1 kinase content and activity. A major difference between tumors and mucosa was found, however, in the phosphorylation of Raf-1. Most of the mucosa samples (13/20), but only 1/20 of the cancer samples, contained hyperphosphorylated Raf-1. EGFR were significantly (p=0.0025) decreased in the tumors. The decreased phosphorylation of Raf-1 in colonic carcinomas could be the result of activation of Raf-1 phosphatases or inactivation of kinases phosphorylating Raf-1. New forms of treatment based on EGFR overexpression do not seem to be suitable for the majority of colonic cancers.This work was supported by the state of Baden-Württemberg (Verbundforschungsprojekt: Aufklärung von Mechanismen der Tumorentstehung und Tumorabwehr). 相似文献
9.
Elizabeth E. Epstein Barbara S. McCrady Linda S. Hirsch 《Alcoholism, clinical and experimental research》1997,21(3):547-556
Current knowledge about alcohol and marital functioning is limited by restrictive sample selection, inattention to the literature on individual-based alcoholic subtypes, and lack of research linking individual differences among alcoholics to marital functioning. The present study was designed to study marital functioning of alcoholics in light of current alcohol typologies. Subjects were part of a larger study on conjoint treatment of alcoholic males and their female partners. Four typologies—including Type 1/2, In-Home/Out-of-home, SteadyIEpisodic, and EarlyILate Onset—were tested for replicability and discriminant validity before linking them to marital functioning. Discriminant validity was found only for the Early (59%)-versus Late (41 %)-Onset typology; thus, further analyses linked only this typology with marital functioning. At baseline, Early-Onset couples reported more marital instability, and the females in these couples were more distressed. During treatment, Early-Onset couples reported higher daily marital satisfaction than Late-Onset couples. Regardless of age of onset, males reported higher marital satisfaction than their spouses during treatment, but their satisfaction did not increase during treatment. Female partners' marital satisfaction increased during treatment. Female partners of Late-Onset males reported particularly low marital satisfaction during treatment. Parsing the sample according to the early-/late-onset typology yielded different predictors of marital satisfaction for males and females within each subtype. For female partners of Early-Onset alcoholics, psychological distress unrelated to her pattner's drinking severity was most associated with her own marital satisfaction, whereas marital adjustment of female partners of Late-Onset alcoholics was most associated with the male's level of perceptual accuracy regarding her needs. This pattern was reversed for the males; marital adjustment of Early-Onset alcoholics was most associated with his partner's perceptual accuracy of his needs, whereas marital functioning of Late-Onset alcoholics was best accounted for by his own psychological distress. 相似文献
10.
Comorbidity and social phobia: evidence from clinical,epidemiologic, and genetic studies 总被引:3,自引:0,他引:3
Kathleen Ries Merikangas Jules Angst 《European archives of psychiatry and clinical neuroscience》1995,244(6):297-303
This paper reviews evidence from clinical, epidemiologic, and family studies regarding the association between social phobia and other syndromes. Social phobia is strongly associated with other anxiety disorders, substance abuse, and affective disorders in both clinical and community samples. An average of 80% of social phobics identified in community samples meet diagnostic criteria for another lifetime condition. Social phobia is most strongly associated with other subtypes of anxiety disorders, with an average of 50% of social phobics in the community reporting a concomitant anxiety disorder including another phobic disorder, generalized anciety, or panic disorder. Approximately 20% of subjects in the community meet lifetime criteria for a major depressive disorder. The onset of social phobia generally precedes that of all other disorders, with the exception of simple phobia. Both clinical severity and treated prevalence are consistently greater among social phobics with comorbid disorders The results of family and twin studies reveal that shared etiologic factors explain a substantial proportion of the comorbidity between social phobia and depression, whereas the association between social phobia and alcoholism derives from a nonfamilial causal relationship between the two conditions. Clinical and phenomenologic implications of these findings are discussed. 相似文献