全文获取类型
收费全文 | 1676275篇 |
免费 | 128357篇 |
国内免费 | 2984篇 |
专业分类
耳鼻咽喉 | 24422篇 |
儿科学 | 46102篇 |
妇产科学 | 45299篇 |
基础医学 | 240644篇 |
口腔科学 | 50931篇 |
临床医学 | 146476篇 |
内科学 | 323208篇 |
皮肤病学 | 34232篇 |
神经病学 | 132275篇 |
特种医学 | 66669篇 |
外国民族医学 | 246篇 |
外科学 | 268563篇 |
综合类 | 39869篇 |
现状与发展 | 3篇 |
一般理论 | 476篇 |
预防医学 | 121764篇 |
眼科学 | 39512篇 |
药学 | 128665篇 |
4篇 | |
中国医学 | 3445篇 |
肿瘤学 | 94811篇 |
出版年
2018年 | 15252篇 |
2016年 | 13276篇 |
2015年 | 15385篇 |
2014年 | 21535篇 |
2013年 | 32170篇 |
2012年 | 43767篇 |
2011年 | 45796篇 |
2010年 | 26951篇 |
2009年 | 25549篇 |
2008年 | 44062篇 |
2007年 | 47070篇 |
2006年 | 47739篇 |
2005年 | 46278篇 |
2004年 | 45162篇 |
2003年 | 43481篇 |
2002年 | 42284篇 |
2001年 | 82958篇 |
2000年 | 85414篇 |
1999年 | 71681篇 |
1998年 | 18710篇 |
1997年 | 16774篇 |
1996年 | 16783篇 |
1995年 | 15771篇 |
1994年 | 14813篇 |
1993年 | 13760篇 |
1992年 | 57370篇 |
1991年 | 55473篇 |
1990年 | 54129篇 |
1989年 | 52683篇 |
1988年 | 48691篇 |
1987年 | 47639篇 |
1986年 | 44746篇 |
1985年 | 43141篇 |
1984年 | 32043篇 |
1983年 | 27311篇 |
1982年 | 15679篇 |
1981年 | 14085篇 |
1979年 | 30587篇 |
1978年 | 21291篇 |
1977年 | 18128篇 |
1976年 | 16193篇 |
1975年 | 17746篇 |
1974年 | 21832篇 |
1973年 | 20795篇 |
1972年 | 19757篇 |
1971年 | 18544篇 |
1970年 | 17681篇 |
1969年 | 17038篇 |
1968年 | 15340篇 |
1967年 | 14047篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
A case of chronic subdural hematoma with anxiety states and concomitant regression-like symptoms 总被引:1,自引:0,他引:1
The authors described an epileptic suffering from head trauma in whom anxiety states and concomitant regression-like symptoms masked the diagnosis of chronic subdural hematoma. Along with the occurrence of chronic subdural hematoma, psychic symptoms were manifested including the anxiety and regression of personality. However, after the chronic subdural hematoma was neurosurgically evacuated, these psychic symptoms gradually disappeared. In the study of organic and symptomatic psychosis, Mackenzie and Popkin (1983) have proposed the concept of an organic anxiety syndrome on the ground that DSM-III provides no organic equivalent for anxiety disorders. Therefore, we presented a case of chronic subdural hematoma in which the direct effect on CNS of this pathological condition was considered to bring about the above-mentioned anxiety disorders with regression-like symptoms. 相似文献
992.
H Ogura H Kubota I Nomura T Tomoda K Araki Y Ogura T Kurashige 《The Japanese journal of antibiotics》1989,42(2):401-410
A new macrolide antibiotic, clarithromycin (TE-031, A-56268), was studied for its clinical efficacy in the field of pediatrics. Patients treated were infants and children ranging from 2 months to 11 years old suffering from acute bronchitis in 5 cases, acute tonsillitis in 2 cases, Mycoplasma pneumonia in 2 cases, pertussis in 6 cases, scarlatina in 1 case and acute enteritis in 2 cases, a total of 18 cases. TE-031 was administered 19.7-43.5 mg/kg in daily doses and lengths of treatment ranged from 4 to 19 days. As regards to its clinical efficacy, good or excellent results were obtained in all cases: excellent in 11 cases and good in 7 cases. No clinical side effects nor abnormal laboratory test values obviously attributable to TE-031 were observed. 相似文献
993.
Optic nerve glioma and the management of optic nerve tumours in the young. 总被引:4,自引:0,他引:4 下载免费PDF全文
Thirty-one patients presenting as orbital optic nerve glioma have been reviewed with maximum follow-up of 14 years. Sixteen of these patients have been reported on previously and further follow-up is provided. Sixteen patients had a stable clinical course with little change over a period of up to 13.5 years. Neurofibromatosis was relatively common in this group (11/16). Fifteen patients had progressive enlargement of the tumour; the incidence of neurofibromatosis in this group was low (4/15). Eleven of these patients were explored neurosurgically and the optic nerve totally excised in 10 of them. The proximal cut end was normal in six patients and the chiasm has apparently remained free of tumour in all of them. We suggest a method of management of primary optic nerve tumours, both meningiomas and gliomas, in young patients. 相似文献
994.
H H Metzler W Stenzl P H Rehak K H Tscheliessnigg W F List 《The Journal of thoracic and cardiovascular surgery》1987,93(6):823-831
Hemodynamic changes after isolated impairment of right ventricular function (produced by increasing afterload by temporary banding of the pulmonary artery) were studied in 22 ventilated pigs during increased levels of positive end-expiratory pressure (4, 8, 12, and 16 cm H2O). In the open chest group, application of positive end-expiratory pressure produced only a slight decrease of cardiac index. After right ventricular damage a decrease of cardiac index of more than 25% occurred only when higher levels of positive end-expiratory pressure were applied. In contrast to the open chest group, the closed chest group showed more distinct cardiovascular responses after positive end-expiratory pressure. In the damaged right ventricle with a positive end-expiratory pressure of 16 cm H2O, right ventricular end-diastolic pressure increased more than 100%. With positive end-expiratory pressure, cardiac index decreased 34% before and 47% after right ventricular damage. We conclude that positive end-expiratory pressure induces a more pronounced decrease in cardiac index if right ventricular function is impaired. During open chest conditions with lower levels of positive end-expiratory pressure, these changes are only small, however, and probably irrelevant. During closed chest conditions, the hemodynamic changes are much more pronounced. High right ventricular end-diastolic pressures resulting from impaired right ventricular contractility as well as from high levels of positive end-expiratory pressure may have an impact on biventricular function and right ventricular coronary driving pressure. 相似文献
995.
Effects of N-(2,6-dimethylphenyl)-2-(2-oxo-1-pyrrolidinyl)acetamide (DM-9384) on learning and memory in rats 总被引:1,自引:0,他引:1
Effects of N-(2,6-dimethylphenyl)-2-(2-oxo-1-pyrrolidinyl) acetamide (DM-9384) on learning and memory were studied using four different experimental rat models. In electroconvulsive shock- or scopolamine-induced amnesia in the step-through passive avoidance task, DM-9384 improved both types of amnesia when administered before the training trial. Aniracetam also showed similar but somewhat weaker effects. Furthermore, in the scopolamine amnesia model, an improvement was confirmed with arecoline. The dose-response curves for these compounds were bell-shaped. In the shuttle box active avoidance task, DM-9384 administered daily 1 hr before each training session facilitated the acquisition process of the avoidance response. In addition, the experiment of light-dark discrimination task with positive reinforcement showed that this compound administered daily after each session slightly accelerated the acquisition process of the correct response. These results suggest an ability of DM-9384 to enhance cognitive functions. 相似文献
996.
Pharmacological properties of fluphenazine-mustard, an irreversible calmodulin antagonist 总被引:1,自引:0,他引:1
We describe an improved synthesis and properties of fluphenazine-mustard, a potent phenothiazine having an alkylating chlorethylamine chain in its structure. The drug possesses anticalmodulin activity equivalent to the parent compound, but unlike fluphenazine dihydrochloride, the mustard derivative irreversibly antagonizes the ability of calmodulin to activate cyclic nucleotide phosphodiesterase. This property is partially calcium-dependent and can be overcome by coincubation with excess fluphenazine dihydrochloride. The compound irreversibly inactivated calmodulin when incubated with intact cells and caused single-stranded breakage of DNA. Fluphenazine-mustard possesses potent antiproliferative and cytotoxic properties against malignant cell lines that are likely to be mediated through both of these actions. 相似文献
997.
998.
Long-term dialysis patients frequently develop acquired renal cystic disease (ARCD). The discovery of ARCD and renal cell carcinoma in one of our hemodialysis patients led us to review the literature. ARCD has been described mainly in the maintenance hemodialysis (MH) population. Therefore, we investigated 20 peritoneal dialysis (PD) patients for ARCD using ultrasonography. Seven patients (35%) had detectable cysts and two patients (10%) had multiple bilateral cysts. One patient had a large asymptomatic complex cyst that proved to be an adenocarcinoma. Our study suggests that ARCD is relatively common in the PD population, and we speculate that it may be related more to length of time in end-stage renal disease (ESRD) than to the mode of dialysis. The potential for malignant change appears to justify a routine screening examination with ultrasonography and/or computerized tomography (CT) to detect this recently described and probably underrecognized entity. 相似文献
999.
1000.