全文获取类型
收费全文 | 3249484篇 |
免费 | 249836篇 |
国内免费 | 6281篇 |
专业分类
耳鼻咽喉 | 48121篇 |
儿科学 | 100107篇 |
妇产科学 | 89117篇 |
基础医学 | 454586篇 |
口腔科学 | 96167篇 |
临床医学 | 291097篇 |
内科学 | 631517篇 |
皮肤病学 | 68759篇 |
神经病学 | 269063篇 |
特种医学 | 129208篇 |
外国民族医学 | 1251篇 |
外科学 | 494595篇 |
综合类 | 78271篇 |
现状与发展 | 7篇 |
一般理论 | 1309篇 |
预防医学 | 252946篇 |
眼科学 | 78193篇 |
药学 | 244129篇 |
8篇 | |
中国医学 | 6378篇 |
肿瘤学 | 170772篇 |
出版年
2018年 | 31684篇 |
2016年 | 27246篇 |
2015年 | 30755篇 |
2014年 | 44177篇 |
2013年 | 67512篇 |
2012年 | 90109篇 |
2011年 | 95215篇 |
2010年 | 56184篇 |
2009年 | 54240篇 |
2008年 | 90858篇 |
2007年 | 97388篇 |
2006年 | 98349篇 |
2005年 | 95979篇 |
2004年 | 92534篇 |
2003年 | 89634篇 |
2002年 | 88547篇 |
2001年 | 149528篇 |
2000年 | 154599篇 |
1999年 | 131101篇 |
1998年 | 37323篇 |
1997年 | 34010篇 |
1996年 | 33193篇 |
1995年 | 32066篇 |
1994年 | 30054篇 |
1993年 | 27959篇 |
1992年 | 104907篇 |
1991年 | 101263篇 |
1990年 | 98270篇 |
1989年 | 95137篇 |
1988年 | 88387篇 |
1987年 | 87097篇 |
1986年 | 82967篇 |
1985年 | 79255篇 |
1984年 | 59913篇 |
1983年 | 51054篇 |
1982年 | 31023篇 |
1981年 | 27789篇 |
1980年 | 26045篇 |
1979年 | 56777篇 |
1978年 | 40178篇 |
1977年 | 34363篇 |
1976年 | 31763篇 |
1975年 | 34484篇 |
1974年 | 41902篇 |
1973年 | 40156篇 |
1972年 | 37999篇 |
1971年 | 35396篇 |
1970年 | 33431篇 |
1969年 | 31372篇 |
1968年 | 28865篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
941.
Increased lymphocyte beta-adrenergic receptor density in progressive multiple sclerosis is specific for the CD8+, CD28- suppressor cell. 总被引:1,自引:0,他引:1
Beta-adrenergic receptor density on T cells from healthy humans is greatest on suppressor cells (CD8+, CD28-) and the effect of catecholamines, secreted by the sympathetic nervous system, predominates on this subset. The sympathetic skin response, a measure of sympathetic nervous system function, is absent in most patients with chronic progressive multiple sclerosis (MS). We measured beta-adrenergic receptor density on suppressor cells, cytotoxic cells, and monocytes from patients with chronic progressive MS and healthy control subjects. Control receptor density on suppressor cells was 2.8 +/- 0.3 fmol/10(6) cells versus a density of 5.1 +/- 0.7 fmol/10(6) cells for patients. Cytotoxic cell (CD8+, CD28+) receptor density was 1.4 +/- 0.4 fmol/10(6) cells in control subjects and 0.9 +/- 0.3 fmol/10(6) cells in the patients. Monocytes displayed beta-adrenergic receptor densities of 2.6 +/- 0.4 fmol/10(6) cells in normal individuals and 2.7 +/- 0.4 fmol/10(6) cells in the patient group. CD8 lymphocyte beta-adrenergic receptor densities in patients with relapsing-remitting and those with stable MS were not different from control values, yet were significantly less than the values for patients with chronic progressive MS. We find that mononuclear cells from healthy control subjects and patients with chronic progressive MS proliferate in response to 200 units/ml of recombinant human interleukin-2 (IL-2) similarly. However, IL-2 treatment increased beta-adrenergic receptor density on normal mononuclear cells, but failed to increase it on mononuclear cells from patients with chronic progressive MS.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
942.
Artificial dopamine agonists are widely employed for the treatment of idiopathic parkinsonism. Pleuropulmonary disease has previously been reported to occur with the use of bromocriptine and mesulergine. We report similar adverse effects induced by the newer agonists lisuride and cabergoline. All these agents are tetracyclic ergot derivatives. This suggests a causal link between ergot-derived dopamine agonists and pleuropulmonary disease. 相似文献
943.
R J Barrnett J P Docherty G M Frommelt 《Journal of the American Academy of Child and Adolescent Psychiatry》1991,30(1):1-14
Reports on individual nonbehavioral child and adolescent psychotherapy since 1963 are reviewed. Inclusion criteria required some minimal contrasting group. Forty-three studies were assessed for basic methodological adequacy and main findings. The authors conclude that summary impressions from this body of literature cannot be made due to the magnitude of the flaws in basic psychotherapy research methodology. Suggestions are made regarding the future of child and adolescent psychotherapy research. 相似文献
944.
Postencephalitic acquired Tourette-like syndrome in a child. 总被引:1,自引:0,他引:1
We report a 6-year-old girl who developed a Tourette-like syndrome following presumed herpes encephalitis. This case suggests that tics can be acquired in childhood and may be associated with lesions involving basal ganglia or limbic circuitry. 相似文献
945.
946.
947.
Computer tomography (CT) of the brain is of value for finding potentially correctable lesions in adult patients with new onset seizures. The value of CT is unknown, however, for finding such lesions in adult chronic epileptic patients without prior CT. We compared a group of 177 adult patients who had CT within a year from the onset of seizures to a group of 93 patients who had a history of seizures for more than a year before CT was performed. In the first group, 33 potentially correctable lesions (19%) were found including 17 tumors. The group with chronic epilepsy had 4 (4%) potentially correctable lesions: 3 arteriovenous malformations and 1 meningioma. It seems that CT is of value in discovering potentially removable lesions in chronic epileptic patients, but the likelihood is relatively small. The incidence of stable structural lesions seems to be similar in the two groups. 相似文献
948.
Forty-two therapists conducting individual psychotherapy with schizophrenic outpatients in a public mental health system responded to a questionnaire that focused on the types of interventions used and the issues and problems encountered in therapy. The therapists spent 59 percent of their time in supportive, problem-solving work and only 32 percent in traditional psychotherapeutic interventions, such as providing insight. The most common issues in therapy were relationship problems, family concerns, depression, losses, and the role of medications in the client's life. The most significant impediments to therapeutic work were the lack of community resources, the client's noncompliance with medications and lack of motivation, and dual diagnoses. Suggestions are offered for improving psychotherapy with schizophrenic outpatients in the public mental health system. 相似文献
949.
950.