全文获取类型
收费全文 | 1278447篇 |
免费 | 95997篇 |
国内免费 | 1619篇 |
专业分类
耳鼻咽喉 | 16459篇 |
儿科学 | 41484篇 |
妇产科学 | 35355篇 |
基础医学 | 191343篇 |
口腔科学 | 34906篇 |
临床医学 | 119463篇 |
内科学 | 250619篇 |
皮肤病学 | 27502篇 |
神经病学 | 103559篇 |
特种医学 | 47034篇 |
外国民族医学 | 265篇 |
外科学 | 180081篇 |
综合类 | 25845篇 |
现状与发展 | 3篇 |
一般理论 | 587篇 |
预防医学 | 106837篇 |
眼科学 | 28254篇 |
药学 | 93423篇 |
7篇 | |
中国医学 | 2030篇 |
肿瘤学 | 71007篇 |
出版年
2019年 | 10815篇 |
2018年 | 14405篇 |
2017年 | 10983篇 |
2016年 | 11898篇 |
2015年 | 13701篇 |
2014年 | 18802篇 |
2013年 | 28472篇 |
2012年 | 39041篇 |
2011年 | 41386篇 |
2010年 | 23720篇 |
2009年 | 22801篇 |
2008年 | 38610篇 |
2007年 | 41120篇 |
2006年 | 40650篇 |
2005年 | 39611篇 |
2004年 | 37953篇 |
2003年 | 36299篇 |
2002年 | 35151篇 |
2001年 | 56071篇 |
2000年 | 57089篇 |
1999年 | 48133篇 |
1998年 | 13439篇 |
1997年 | 12247篇 |
1996年 | 12654篇 |
1995年 | 11931篇 |
1994年 | 11123篇 |
1993年 | 10407篇 |
1992年 | 38211篇 |
1991年 | 37683篇 |
1990年 | 36456篇 |
1989年 | 35267篇 |
1988年 | 32698篇 |
1987年 | 32030篇 |
1986年 | 30528篇 |
1985年 | 28795篇 |
1984年 | 21950篇 |
1983年 | 19193篇 |
1982年 | 11368篇 |
1979年 | 20950篇 |
1978年 | 15395篇 |
1977年 | 12792篇 |
1976年 | 11847篇 |
1975年 | 12818篇 |
1974年 | 15595篇 |
1973年 | 15368篇 |
1972年 | 14515篇 |
1971年 | 13555篇 |
1970年 | 12788篇 |
1969年 | 12065篇 |
1968年 | 11231篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
AIMS: To examine the effects of agents that alter potassium adenosine triphosphate (KATP) channel activity in beta-cells on cognitive function and counterregulatory hormone responses during acute hypoglycaemia, given the physiological similarities between the pancreatic beta-cell and the hypothalamic glucose-sensitive neurones (GSN) and the widespread distribution of sulphonylurea receptors in neuronal cells throughout the brain. METHODS: Ten healthy males were studied on four occasions and in random order underwent three stepped hypoglycaemic (plasma glucose aims: 3.4, 2.8, 2.4 mmol/l) and one euglycaemic (plasma glucose aim: 5 mmol/l) insulin clamps. Prior to each hypoglycaemic study, volunteers received either 10 mg glibenclamide, or 5 mg/kg diazoxide or placebo orally. Cognitive function, symptom scores and counterregulatory hormone responses were measured at each glycaemic level. RESULTS: There was no statistically significant effect of either drug on the symptoms generated or the counterregulatory hormonal response during hypoglycaemia. However, cognitive function was better preserved during hypoglycaemia in the glibenclamide-treated arm, particularly four-choice reaction time which deteriorated at a plasma glucose 2.5 mmol/l compared with 3.0 mmol/l with diazoxide (P = 0.015) and 2.9 mmol/l with placebo (P = 0.114). CONCLUSIONS: Single doses of pharmacological agents which alter membrane KATP channel activity do not affect the counterregulatory response to hypoglycaemia but may modify cognitive function during cerebral glucopenia. The unexpected effects of glibenclamide on cortical function suggest a novel action of sulphonylureas that warrants further investigation. 相似文献
52.
S Chinn S H Downs J M Anto M W Gerbase B Leynaert R de Marco C Janson D Jarvis N Künzli J Sunyer C Svanes E Zemp U Ackermann-Liebrich P Burney 《The European respiratory journal》2006,28(4):763-771
The incidence of asthma has been reported to be associated with obesity. An alternative analysis, of net change in prevalence, does not require exclusion of those with asthma at baseline. Follow-up data were obtained from 9,552 participants in the European Community Respiratory Health Survey and the Swiss cohort Study on Air Pollution and Lung Disease in Adults. Incidence of asthma was analysed by proportional hazards regression, and net changes in symptoms and asthma status by generalised estimating equations, by obesity group. Incidence and net change in ever having had asthma were greater in females than in males, and in participants who remained obese compared with those who were never obese (hazard ratio 2.00, 95% confidence interval 1.25-3.20; excess net change 2.8%, 0.4-5.3% per 10 yrs). The effect of being obese on net change in diagnosed asthma was greater in females than in males, but for net change in wheeze without a cold it was greater in males. The present results are consistent with asthma being more frequently diagnosed in females, especially obese females. These findings may help to explain the reports of a stronger association between asthma and obesity in females than in males. 相似文献
53.
54.
55.
Decreases in sex hormone levels with menopause may bring about a number of consequences in women's general health and sexual well-being, especially when levels decline suddenly and prematurely, as in surgical menopause. In addition to the well-established role of estrogens in preserving the biological basis of sexual response, there is emerging evidence that androgens are significant independent determinants affecting sexual desire, activity and satisfaction, as well as mood, energy and other components of women's health. Hypoactive sexual desire disorder (HSDD), a persistent absence of sexual fantasies or thoughts and/or desire for and receptivity to sexual activity that causes personal distress, is experienced by some postmenopausal women. Even though conventional hormone therapy with estrogens or estrogens and progestogens may be effective for vaginal atrophy, increasing vaginal lubrication and reducing dyspareunia, it has not been shown to consistently increase sexual desire or activity and many women with sexual dysfunction remain unresponsive. Several recent, large, phase III studies have shown that the addition of transdermal testosterone to conventional hormone therapy can be helpful in surgically menopausal women presenting with HSDD. After 24 weeks of treatment in these studies, testosterone-treated women experienced significantly greater increases in satisfying sexual activity and sexual desire, and greater decreases in distress, than placebo-treated women. Accurate clinical assessment and individualized management of sexual symptoms are fundamentally important for all menopausal women with HSDD or other sexual problems. 相似文献
56.
Adriana B Campaner Alessandro Scapinelli Ruy O Machado Roberto E Dos Santos Geni W Beznos Tsutomu Aoki 《Gynecological endocrinology》2006,22(7):395-398
We report a case of a prepubertal girl with juvenile primary hypothyroidism presenting as ovarian cysts and precocious puberty. The 7-year-old female was referred to our clinic because of a pelvic/abdominal mass and vaginal bleeding. Besides these findings, on physical examination we noticed the thyroid gland globally increased and the presence of secondary sexual characteristics. Based upon the clinical profile and investigations, the patient was diagnosed with juvenile primary hypothyroidism due to autoimmune thyroiditis. The cysts and precocious puberty resolved spontaneously after the simple replacement of thyroid hormone. It is important to bear in mind hypothyroidism in cases of girls presenting ovarian cysts and precocious puberty in order to avoid unnecessary surgery on the ovaries. 相似文献
57.
Abstract: Background: Identification of risk drinking in expectant fathers may be helpful as an important part of efforts to minimize maternal alcohol use, and as an opportunity to inform them about a problematic practice during a critical developmental stage for the couple. The purpose of this study was to evaluate the T‐ACE screening questionnaire, which asks about t olerance to alcohol, being a nnoyed by other's comments about drinking, attempts to c ut down, and having a drink first thing in the morning (“ e ye‐opener”), in the male partners of pregnant women who themselves were T‐ACE positive. Methods: Two hundred fifty‐four male partners were asked to complete the T‐ACE embedded in a health survey, the Alcohol Use Disorders Identification Test (AUDIT), and other questions about their alcohol use in the past 30 days when their pregnant partners had a median gestation of 11.5 weeks (T1). After delivery, male partners again completed the T‐ACE and quantity‐frequency questions (T2). The predictive ability of the T‐ACE and AUDIT was compared, using risk drinking (>4 drinks/day or >14 drinks/week) as the criterion standard. Results: A substantial minority of male partners had risk drinking, 31 percent at T1 and 25 percent at T2. Although the AUDIT was better than the T‐ACE as an independent predictor of risk drinking, the latter was most accurate when the tolerance threshold exceeded 2 drinks, the same established for pregnant women. The sensitivity (T1 = 84.6%, T2 = 82.8%) and specificity (T1 = 43.8%, T2 = 51.1%) of the T‐ACE at this threshold compared favorably with those of the AUDIT at the standard cut point of 8. Conclusions: The T‐ACE may be a practical way for clinicians to identify risk drinking in both pregnant women and expectant fathers. (BIRTH 33:2 June 2006) 相似文献
58.
59.
In einer clusteranalytischen Untersuchung mit 137 Patienten, die einen Parasuizid verübt hatten, wurden 6 Subgruppen unter Berücksichtigung der Klassifikationsvariable “suicide intent” isoliert. Es wurde die Hypothese geprüft, dass sich sowohl die Motivstrukturen als auch die Raten an wiederholten Parasuiziden in Abh?ngigkeit der Clusterl?sung bedeutsam voneinander unterscheiden. Die Ergebnisse unterstützen die Annahme einer zunehmenden Ausdifferenzierung der interpersonell orientierten Motivstrukturen mit sinkendem bzw. einer Einengung der Motivstruktur auf den Todeswunsch mit steigendem “suicide intent”. Es wurden folgende Subgruppen differenziert: eine Suizid-Hochrisikogruppe mit ausschlie?licher Todesintention und -motivation, 2 moderate Suizid-Risikogruppen mit hoher Todesintention und leichten Tendenzen zu interpersoneller Motivation, eine Subgruppe, gekennzeichnet durch eine manipulativ/strategisch orientierte Motivstruktur und auff?llig h?ufigen Parasuizidwiederholungen, eine Subgruppe mit vorrangig appellativ orientierten Motiven, Kontrollverlust und vergleichsweise seltenen Parasuizidwiederholungen und eine Subgruppe mit ambivalenter Motivstruktur (interpersonell und todesorientiert). 相似文献
60.