全文获取类型
收费全文 | 899533篇 |
免费 | 62448篇 |
国内免费 | 2334篇 |
专业分类
耳鼻咽喉 | 12474篇 |
儿科学 | 28676篇 |
妇产科学 | 26143篇 |
基础医学 | 126575篇 |
口腔科学 | 24686篇 |
临床医学 | 74750篇 |
内科学 | 183137篇 |
皮肤病学 | 18984篇 |
神经病学 | 71386篇 |
特种医学 | 36445篇 |
外国民族医学 | 336篇 |
外科学 | 142105篇 |
综合类 | 19030篇 |
一般理论 | 247篇 |
预防医学 | 64556篇 |
眼科学 | 20083篇 |
药学 | 63806篇 |
中国医学 | 1798篇 |
肿瘤学 | 49098篇 |
出版年
2018年 | 9048篇 |
2017年 | 7160篇 |
2016年 | 7674篇 |
2015年 | 8722篇 |
2014年 | 12367篇 |
2013年 | 19210篇 |
2012年 | 25647篇 |
2011年 | 27256篇 |
2010年 | 16572篇 |
2009年 | 15780篇 |
2008年 | 26124篇 |
2007年 | 27731篇 |
2006年 | 27913篇 |
2005年 | 27444篇 |
2004年 | 26291篇 |
2003年 | 25462篇 |
2002年 | 25051篇 |
2001年 | 41356篇 |
2000年 | 42551篇 |
1999年 | 36265篇 |
1998年 | 9966篇 |
1997年 | 9148篇 |
1996年 | 9082篇 |
1995年 | 8445篇 |
1994年 | 8081篇 |
1993年 | 7584篇 |
1992年 | 28198篇 |
1991年 | 26979篇 |
1990年 | 26408篇 |
1989年 | 25345篇 |
1988年 | 23553篇 |
1987年 | 23170篇 |
1986年 | 22250篇 |
1985年 | 21151篇 |
1984年 | 15806篇 |
1983年 | 13477篇 |
1982年 | 8087篇 |
1979年 | 14589篇 |
1978年 | 10208篇 |
1977年 | 8627篇 |
1976年 | 8147篇 |
1975年 | 8959篇 |
1974年 | 10697篇 |
1973年 | 10182篇 |
1972年 | 9661篇 |
1971年 | 8917篇 |
1970年 | 8584篇 |
1969年 | 8025篇 |
1968年 | 7684篇 |
1967年 | 7086篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
941.
Twenty-eight osteosarcomas (OS) of the jaw were reported. There were 15 male and 13 female patients (age range, 9 to 68 years; mean, 36.9 years); 57.1% of the patients were older than 30 years of age. Swelling was the most frequent symptom; it was reported on an average of 6 months before diagnosis. Most of the tumors of the maxilla (eight patients) occurred in the alveolar ridge (six of eight). In the mandible (20 patients), the body was the preferred site (11 of 20). Radiographically most of the lesions were either lytic and sclerotic or only lytic. Histologically, 12 cases (42.9%) were osteoblastic osteosarcoma, ten (35.8%) were chondroblastic, four (14.3%) were fibroblastic, and two (7%) were round cell OS. Of the 28 cases, three (10.7%) were low grade, and 25 (89.3%) were high grade. Thirteen patients had intralesional surgery, and 13 had marginal surgery as their initial treatment. Recurrence was the rule in the first group, and it was 69% in the second group. Twenty patients (71%) died, and eight are alive. Of these, two are alive with disease. In the six patients who are alive and disease-free, all but one had marginal to wide surgical margins at the time of the first procedure or wide margins at the time of the recurrences along with chemotherapy or radiation therapy. In the patient in which the surgical margins were marginal, the lesion was small 2.5 X 2 cm. This patient was alive without evidence of disease after 9 years of follow-up. 相似文献
942.
943.
Personality of patients with pseudoseizures 总被引:7,自引:0,他引:7
We studied personality features of 19 patients with pseudoseizures (PS) only. Scores on a personality inventory (MMPI) were compared with those of adults with generalized seizures and correlated to cognitive measures (Halstead-Reitan). Mean MMPI scores did not differ significantly, and no profile distinguished PS and epilepsy patients. MMPI abnormalities of PS patients were diverse and seldom characteristic of hysteria. Eight PS patients had cognitive impairment, two without MMPI evidence of personality disorder. These findings suggest that the etiology of pseudoseizures is multifactorial, involving different psychopathologies and sometimes cerebral dysfunction. 相似文献
944.
Abnormal pressor responses are known to occur in the maternal circulation in pregnancy-induced hypertension (PIH), but little is know of the response of the foetal circulation. The responsiveness of umbilical arteries in PIH can be studied after delivery, and this is a useful model to explore the pathophysiological mechanisms involved. In the present experiments, the in vitro response of umbilical artery rings to bradykinin and 5-hydroxytryptamine (5-HT) was tested and ultrastructural changes investigated. Umbilical arteries from 48 cords were studied. Fifteen of the mothers had PIH, five had essential hypertension pre-dating the pregnancy and five had diabetes. Twenty-three women had pregnancies uncomplicated by hypertension or serious medical or obstetric problems and these served as controls. Umbilical arteries from the severe proteinuric PIH group were significantly more responsive to 5-HT as assessed by affinity constants (P less than 0.05). The responsiveness of arteries from all other groups did not differ from the normal cases. A probable mechanism for the findings is endothelial damage as a result of pre-eclamptic disease. This was substantiated by ultrastructural evidence. 相似文献
945.
COMPARISON OF THE EFFECTS OF ATROPINE AND GLYCOPYRROLATE ON COGNITIVE FUNCTION FOLLOWING GENERAL ANAESTHESIA 总被引:2,自引:1,他引:1
Tests of orientation, concentration and shortterm visual memorywere used to assess 72 patients 1 day before, and 2 days after,elective major surgery. Patients were premedicated with papaveretumand either atropine or glycopyrrolate, before receiving a standardgeneral anaesthetic. Those who had received atropine showedsignificant postoperative short-term memory deficit (P< 0.01),but no change in orientation or concentration. Those who hadbeen given glycopyrrolate showed no significant cognitive changesafter surgery. As glycopyrrolate does not cross the blood-brainbarrier freely, these findings support the involvement of centralcholinergic mechanisms in the deterioration of cognitive functionin the postoperative period. 相似文献
946.
M Teramachi F Tanaka H Esaki R Inoue M Ito K Kobayashi 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1989,37(11):2393-2397
A 14-year-old junior high school boy was admitted to our institute. Previously he had been diagnosed as having peripheral pulmonary stenosis (Gay's classification, type IV) at the age of 2 years and 10 months. On this occasion, however, a diagnosis of supravalvular aortic stenosis was made, with a pressure gradient of about 120 mmHg, and all examinations showed spontaneous remission of peripheral pulmonary stenosis. He underwent a successful standard aortoplasty. This is the first reported case of spontaneous remission of peripheral pulmonary stenosis. 相似文献
947.
F Bollengier 《Zeitschrift für klinische Chemie und klinische Biochemie》1987,25(9):589-593
Cystatin C, alias post-gamma-globulin or gamma-trace protein, has been shown to be a potent inhibitor of cysteine proteinases; this protein is normally present in different biological fluids, but particularly so in cerebrospinal fluid. The concentration of cystatin C was determined by radial immunodiffusion in cerebrospinal fluid from patients affected with multiple sclerosis, patients affected with various neurological diseases and in controls; it was also determined in brain tissue from 2 patients affected with multiple sclerosis and 3 control brains. Cystatin C cerebrospinal fluid levels were undetectable or depressed in many multiple sclerosis cases and the median value differed significantly from the control one. Its low concentration in multiple sclerosis suggests that the regulation of cysteine proteinases is impaired in this disease; hence enhanced activity of cysteine proteinases could initiate, or increase the breakdown of myelin. Although it is perhaps a little premature to consider cystatin C as a marker for multiple sclerosis, this protein is nevertheless associated to demyelination; consequently its biochemical assay in cerebrospinal fluid is recommended as a complementary diagnostic tool. 相似文献
948.
A unilateral pseudobulbar syndrome consequent to unilateral capsulothalamic infarction is described. Motor deficit of the face was associated with marked velar and pharyngeal unilateral palsy; paresis of limbs was mild. ACT scan revealed a circumscribed infarction of the genu of the internal capsule. This raised the problem of unilateral supranuclear pharyngeal palsies and of the precise anatomy of the genicular tract in the genu of the internal capsule. 相似文献
949.
950.
Posterior ischemic optic neuropathy during general surgery 总被引:3,自引:0,他引:3
We examined two patients who awoke with profound bilateral visual loss after operations under general anesthesia. Their fundi, initially normal, later showed bilateral optic atrophy. Neither patient showed other neurologic deficits, although one demonstrated radiologic evidence of a small cerebral infarction in the deep white matter. These patients probably suffered intraoperative infarction of the retrobulbar segments of both optic nerves, producing posterior ischemic optic neuropathy. Profound systemic hypotension may have been a contributing factor in one patient, the use of the pump-oxygenator in the other, and anemia in both. 相似文献