全文获取类型
收费全文 | 2999343篇 |
免费 | 232148篇 |
国内免费 | 5161篇 |
专业分类
耳鼻咽喉 | 43518篇 |
儿科学 | 89170篇 |
妇产科学 | 78667篇 |
基础医学 | 422866篇 |
口腔科学 | 88193篇 |
临床医学 | 270614篇 |
内科学 | 584587篇 |
皮肤病学 | 61430篇 |
神经病学 | 247353篇 |
特种医学 | 119183篇 |
外国民族医学 | 941篇 |
外科学 | 461724篇 |
综合类 | 68297篇 |
现状与发展 | 2篇 |
一般理论 | 1156篇 |
预防医学 | 232820篇 |
眼科学 | 70607篇 |
药学 | 227405篇 |
7篇 | |
中国医学 | 5868篇 |
肿瘤学 | 162244篇 |
出版年
2018年 | 29814篇 |
2016年 | 25529篇 |
2015年 | 28905篇 |
2014年 | 41208篇 |
2013年 | 62355篇 |
2012年 | 84260篇 |
2011年 | 88840篇 |
2010年 | 52395篇 |
2009年 | 50176篇 |
2008年 | 85014篇 |
2007年 | 90110篇 |
2006年 | 91474篇 |
2005年 | 89023篇 |
2004年 | 85833篇 |
2003年 | 82720篇 |
2002年 | 81641篇 |
2001年 | 145848篇 |
2000年 | 151093篇 |
1999年 | 127568篇 |
1998年 | 34958篇 |
1997年 | 31557篇 |
1996年 | 31376篇 |
1995年 | 30178篇 |
1994年 | 28335篇 |
1993年 | 26314篇 |
1992年 | 101957篇 |
1991年 | 98367篇 |
1990年 | 95017篇 |
1989年 | 91950篇 |
1988年 | 85009篇 |
1987年 | 83398篇 |
1986年 | 78833篇 |
1985年 | 75376篇 |
1984年 | 56253篇 |
1983年 | 47964篇 |
1982年 | 28008篇 |
1981年 | 24834篇 |
1980年 | 23209篇 |
1979年 | 52146篇 |
1978年 | 36252篇 |
1977年 | 30772篇 |
1976年 | 28318篇 |
1975年 | 30245篇 |
1974年 | 37203篇 |
1973年 | 35292篇 |
1972年 | 33189篇 |
1971年 | 30872篇 |
1970年 | 29084篇 |
1969年 | 27222篇 |
1968年 | 24714篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
Current trend in the treatment of Hodgkin's disease 总被引:1,自引:0,他引:1
M Tubiana J L Amiel M Hayat M Henry-Amar J M Cosset J P Droz P Carde 《Radiation Medicine》1983,1(3):221-229
The analysis of three subsequent randomized trials carried out within the frame of the European Organization for Research on Cancer (E.O.R.T.C.) enables to define a strategy for the staging and the treatment of early stages of Hodgkin's disease. Several prognostic factors were identified by multivariate analyses: 1) erythrocyte sedimentation rate, which has a greater impact on relapse-free survival than systemic symptoms but which can be combined with them; the combination of the two is a more powerful prognostic indicator than ESR alone; 2) the number of involved lymphatic areas: patients with one or two lymphatic areas involved (CS I and II2) have a better outcome than stage II patients with 3 or more areas involved (CS II3). Patients with favorable prognostic indicators are submitted to staging laparotomy because for them spleen involvement has a pejorative impact. For patients with unfavorable indicators, the spleen involvement has little prognostic significance and therefore those patients who need, anyway, an aggressive treatment do not undergo staging laparotomy. Patients with favorable prognostic indicators and negative staging laparotomy can be treated by radiotherapy alone, patients with positive laparotomy or patients with unfavorable prognostic indicators are treated by combination of multiple chemotherapy and radiotherapy. 相似文献
994.
Meir Steiner Richard J. Katz Giulio Baldrighi Bernard J. Carroll 《Psychoneuroendocrinology》1981,6(1):81-90
(1) The estrous cycle in the rat may be used to study recurrent changes in motor behaviors and motivation which are strongly related to cyclic hormonal and CNS changes. (2) The peak in motivated behaviors occurs during a sharply defined period on the night between proestrus and estrus and is evident in facilitated wheel-running, lordosis, and intracranial self-stimulation. (3) Behaviors without a clearly motivated character do not show an estrous cyclicity. (4) The estrous cyclic variation in intracranial self-stimulation was observed at a specific locus — the pars campacta of the substantia nigra. (5) A neurochemical link between sexually motivated behavior, wheel running and intracranial self-stimulation is suggested. This link is in part dopaminergic but is probably also activated by many other systems. 相似文献
995.
996.
Anal dilatation is still used in the treatment of anal fissure and haemorrhoids. Using anorectal physiology and anal endosonography we have studied 12 men presenting with faecal incontinence following anal dilatation. Resting anal pressures were low, pudendal nerve latencies were normal; 11 men had a disrupted internal anal sphincter and in ten this was extensively fragmented. Three also had defects of the external anal sphincter. These findings demonstrate for the first time the nature of the structural injury which may be caused by anal dilatation. 相似文献
997.
998.
Protein-calorie malnutrition (PCM) impairs immune responsiveness predisposing to Candida albicans sepsis, but mechanisms are unclear. This study examined the effect of PCM on enteric-derived C. albicans intestinal translocation and the ability of in vivo interferon-gamma (IFN-gamma) to upregulate macrophage (MO) candidacidal mechanisms in PCM mice. Control (24% casein) and low protein (2.5%) diets were given for 4 weeks. Mice (n = 160) were fed C. albicans in their drinking water for 3 days and C. albicans translocation (mean colony-forming units (CFU)/g tissue +/- SEM) to the GI tract, liver, spleen, and kidney was assessed at 1 and 5 days following endotoxin challenge of 1, 5, and 10 mg/kg body wt. In a separate study (n = 100 mice), IFN-gamma (1000-10,000 U/day ip) vs saline was given for 3 days prior to harvesting peritoneal macrophages for assay of superoxide anion (O2-), percentage macrophage phagocytosis of C. albicans, and percentage killing of C. albicans. On Day 1, fungal translocation to the intestinal wall and systemic organs in the PCM group was significantly higher. On Day 5, mean CFU were significantly higher in the PCM group, indicating impaired organ clearance. Mean O2-, phagocytosis, and killing were significantly impaired in the PCM group (P less than 0.05), but IFN-gamma improved all functions. PCM significantly depressed host responses to C. albicans. IFN-gamma treatment enhanced candidacidal mechanisms, suggesting a therapeutic role in the malnourished host predisposed to C. albicans sepsis. 相似文献
999.
The extracellular electrophysiological properties of neurons in the laterodorsal tegmental nucleus (LDT), a major source of cholinergic afferents to the thalamus, were studied in chloral hydrate-anesthetized rats. A combination of antidromic activation from the thalamus and histological verification of recording sites was used to correlate the identity of extracellular recordings in the rat LDT with cholinergic neurons in that region. All neurons antidromically activated by stimulation of the anteroventral thalamus were histologically verified to be within clusters of cholinergic (NADPH-d-positive) cells in the LDT or in the adjacent nucleus locus coeruleus (LC). The thalamically projecting LDT neurons had a homogeneous neurophysiological profile consisting of long duration action potentials (mean = 2.5 ms), slow conduction velocities (mean = 0.78 m/s), and lengthy chronaxie values (mean = 0.725 ms). The appearance and axonal characteristics of these neurons resembled those of noradrenergic LC neurons, but the two populations exhibited substantially different spontaneous activity patterns and sensory responsiveness. These characteristics may be useful in the preliminary identification of putative cholinergic neurons in vivo, and thereby provide a foundation for exploring the neuropharmacology, afferent modulation, sensory responsiveness and behavioral correlates of the brainstem cholinergic system. 相似文献
1000.
Deep venous thrombosis and pulmonary embolism 总被引:2,自引:0,他引:2
All surgical patients are at risk for the development of deep venous thrombosis and subsequent pulmonary embolism or postphlebitic syndrome. The evolution of ultrasonographic imaging has increased the awareness of prevention, diagnosis, and treatment of deep venous thrombosis. Duplex imaging and Doppler color flow imaging have made the diagnosis of deep venous thrombosis relatively simple, painless, inexpensive, and definitive. These procedures have gained acceptance by both patients and physicians. Several risk factors have been identified that increase the chance of the development of deep venous thrombosis. These factors include a history of deep venous thrombosis, presence of a malignant process, increasing age, cigarette smoking, obesity, prolonged bed rest, and general anesthesia. The greater the number of risk factors, the more aggressive prophylaxis should be. Means of prophylaxis have improved, and surgeons now generally agree that some form of prophylaxis is required. Heparin and intermittent compression devices appear to be equally effective in preventing deep venous thrombosis. The addition of venous monitoring in high-risk patients permits immediate identification of the presence of deep venous thrombosis. During the last decade, the treatment of patients with deep venous thrombosis has changed little. Heparin followed by warfarin remains the treatment of choice. A small group of patients receive fibrinolytic therapy for deep venous thrombosis. Although the incidence of postoperative deep venous thrombosis has decreased during the last decade, it remains a significant complication. 相似文献