全文获取类型
收费全文 | 2391217篇 |
免费 | 182960篇 |
国内免费 | 4596篇 |
专业分类
耳鼻咽喉 | 31749篇 |
儿科学 | 78842篇 |
妇产科学 | 68017篇 |
基础医学 | 348044篇 |
口腔科学 | 66109篇 |
临床医学 | 220291篇 |
内科学 | 468735篇 |
皮肤病学 | 53609篇 |
神经病学 | 194943篇 |
特种医学 | 89740篇 |
外国民族医学 | 702篇 |
外科学 | 347581篇 |
综合类 | 53632篇 |
现状与发展 | 4篇 |
一般理论 | 972篇 |
预防医学 | 193848篇 |
眼科学 | 54466篇 |
药学 | 171661篇 |
8篇 | |
中国医学 | 4907篇 |
肿瘤学 | 130913篇 |
出版年
2019年 | 19195篇 |
2018年 | 26493篇 |
2017年 | 20246篇 |
2016年 | 22587篇 |
2015年 | 25523篇 |
2014年 | 35940篇 |
2013年 | 54282篇 |
2012年 | 73584篇 |
2011年 | 78474篇 |
2010年 | 45948篇 |
2009年 | 44001篇 |
2008年 | 73184篇 |
2007年 | 77975篇 |
2006年 | 77998篇 |
2005年 | 75938篇 |
2004年 | 72911篇 |
2003年 | 69636篇 |
2002年 | 67432篇 |
2001年 | 111878篇 |
2000年 | 114226篇 |
1999年 | 95379篇 |
1998年 | 27153篇 |
1997年 | 24637篇 |
1996年 | 24964篇 |
1995年 | 23685篇 |
1994年 | 21770篇 |
1993年 | 20362篇 |
1992年 | 73838篇 |
1991年 | 71699篇 |
1990年 | 69065篇 |
1989年 | 66519篇 |
1988年 | 61325篇 |
1987年 | 59964篇 |
1986年 | 56561篇 |
1985年 | 53746篇 |
1984年 | 41008篇 |
1983年 | 35276篇 |
1982年 | 21190篇 |
1981年 | 19183篇 |
1979年 | 37631篇 |
1978年 | 27188篇 |
1977年 | 22653篇 |
1976年 | 21211篇 |
1975年 | 22320篇 |
1974年 | 27119篇 |
1973年 | 26455篇 |
1972年 | 24942篇 |
1971年 | 22981篇 |
1970年 | 21719篇 |
1969年 | 20359篇 |
排序方式: 共有10000条查询结果,搜索用时 10 毫秒
991.
Differential distribution of pepsinogen II between the zones of the human prostate and the seminal vesicle 总被引:2,自引:0,他引:2
J H Reese J E McNeal E A Redwine I M Samloff T A Stamey 《The Journal of urology》1986,136(5):1148-1152
Pepsinogen II (PG II) is a gastric proenzyme which has previously been found in both human seminal fluid and the prostate gland. However, no regional distribution of PG II has been noted within the prostate nor has it been found in the seminal vesicle. Bouins-fixed sections of central zone, peripheral zone and seminal vesicle, taken from 10 prostates removed at radical prostatectomy or cystectomy, were exposed to antibody against PG II and stained using the A-B-C immunoperoxidase technique. Formalin-fixed tissue from autopsy prostates of four men in the third decade, and six cases with BPH nodules, were also examined for PG II activity. In nine of 10 seminal vesicles, and seven of 10 central zone samples, more than 50 per cent of the cells stained positive for PG II. By contrast, in nine of 10 peripheral zone samples staining was present in five per cent or less of the epithelial cells. Similarly, PG II activity in the four autopsy prostates occurred almost entirely within the central zone and ended abruptly at the boundary between the peripheral and central zones. BPH nodules contained no PG II activity. These findings provide the first evidence that the central and peripheral zones may serve different biological functions. Embryologically it is currently thought that the prostate is of endodermal origin and the seminal vesicle of mesodermal origin. The presence of large amounts of PG II in both the seminal vesicle and central zone lends support to the hypothesis of a common mesodermal origin for these two structures. 相似文献
992.
993.
M Altissimi R Antenucci C Fiacca G B Mancini 《Clinical orthopaedics and related research》1986,(206):202-210
The long-term results of the conservative treatment of wrist fractures were observed in a follow-up study of 297 cases over a period of one and one-half years to six years. The evaluation of the results was based on clinical parameters, both subjective and objective, as well as radiological features. The results were: excellent in 38% of cases, good in 49%, fair in 11.5%, and poor in 1.5%; considerably worse were the subjective results (20% fair to poor). No statistically significant relation could be found between results and type of fracture. Clinical deformities and pain in the area of the distal radioulnar joint were frequent. Decrease in grip strength was observed in 17.8% of cases. A limitation of wrist movement was not frequent. Numerous compressive neuropathies were found (41 in 35 patients), especially of the median nerve. The values relative to the three radiographic parameters under investigation (that is, radial deviation, volar tilt, and radioulnar index) were often found to be out of the normal range. The comparative study of postreduction and follow-up radiograms show the loss of reduction to be frequent, especially as far as the volar tilt is concerned. The frequent radiologic deformities are associated with significantly bad results only in cases of extremely abnormal values. However, fractures of the distal radius are not to be underestimated. Long-term results following conservative treatment may not be as acceptable as is generally assumed. 相似文献
994.
The impact of percutaneous transluminal angioplasty on the management of peripheral vascular disease 总被引:1,自引:0,他引:1
J B Anderson A P Wolinski I P Wells D C Wilkins B P Bliss 《The British journal of surgery》1986,73(1):17-19
Percutaneous transluminal angioplasty is a well established technique with wide application, but its place in the overall management of peripheral vascular disease is not well defined. This study compares similar groups of patients with peripheral vascular disease in 1981 and 1984, before and after the introduction of the technique to a district general hospital. More patients are now being investigated and treated and this is almost entirely due to the availability of angioplasty. The rates for surgery have not changed. Percutaneous transluminal angioplasty should therefore be seen as a new and separate form of treatment for peripheral vascular disease, not necessarily influencing or replacing surgery, and requiring its own allocation of resources in accordance with the increase in the level of care afforded by the technique. 相似文献
995.
We describe five new cases of autosomal recessive distal dystrophy (Miyoshi myopathy) and emphasize the distinctive clinical and laboratory features of this unusual muscular dystrophy. Symptoms began at age 15 to 25, the gastrocnemius muscles were selectively involved, and creatine kinase was elevated more than 10 times normal. The EMG showed abundant brief motor units with numerous fibrillations. Dystrophic features without vacuoles were best seen in the biceps femoris muscle. Asymptomatic creatine kinase elevation was present years prior to the development of weakness. The disorder appears to be inherited in an autosomal recessive pattern. Miyoshi myopathy can be distinguished from other distal muscular dystrophies. We propose a new classification for the distal muscular dystrophies. 相似文献
996.
997.
J. Duteil FA Rambert AM Pointeau P. Mangiameli and E. Assous 《Fundamental & clinical pharmacology》1991,5(8):695-708
The potential antidepressant effect of flerobuterol (dl-(fluoro-2 phenyl)-1 t-butylamino-2 ethanol), a new drug related to beta-adrenoceptor agonists, was evaluated and compared with imipramine and salbutamol using classical psychopharmacological tests in mice. Like imipramine and salbutamol, flerobuterol (0.5-32 mg kg-1, ip) fully prevented apomorphine (16 mg kg-1, sc)- and partly reversed reserpine- and oxotremorine-induced hypothermia. At higher doses (16-32 mg kg-1), flerobuterol enhanced the toxic effects of yohimbine. Unlike imipramine, flerobuterol and salbutamol did not reduce immobility duration in the behavioural despair test. Salbutamol and flerobuterol decreased locomotor activity. Flerobuterol did not induce mydriasis, did not prevent oxotremorine-induced tremors or salivary and lacrimal gland secretion and did not reduce reserpine-induced palpebral ptosis. Propranolol (8 mg kg-1, ip) but not alpha-methyl-paratyrosine (75 mg kg-1, ip) prevented the flerobuterol-induced antagonism of apomorphine-induced hypothermia. Our results suggest that flerobuterol demonstrates potential antidepressant activity, which could be related to beta-adrenoceptor activation in mice. 相似文献
998.
G C Lin 《中华口腔医学杂志》1991,26(3):137-9, 190
From 1955 to 1984, radical neck dissection (RND) had been done in 300 salivary carcinoma patients, 114 of which had regional lymph node metastasis, with a 38% metastatic rate. Respective 3, 5, 10, 15, 20 year survival rates were 76, 64, 47, 35, 35% in a 3 to 20 years follow-up study in 283 patients (94.33%). The following four points are concluded: 1. The metastatic rate is determined not only on tumor staging, but more to its typing (pathologic behaviour). 2. Elective RND gave a better prognosis than therapeutic and negative metastasis has a better survival chance than positive where the low level metastasis is the worst. 3. According to pathologic typing, Elective RND is indicated for undifferentiated adenocarcinoma, high malignant mucoepidermoid carcinoma, squamous cell carcinoma, adenocarcinoma and papillary cystic adenocarcinoma, therapeutic RND for malignant pleomorphic adenoma, acinic cell carcinoma and mucoepidermoid carcinoma. 4. Unilateral RND is indicated for all but sublingual and buccal tumors. 相似文献
999.
Quality of object relations versus interpersonal functioning as predictors of therapeutic alliance and psychotherapy outcome 总被引:1,自引:0,他引:1
W E Piper H F Azim A S Joyce M McCallum G W Nixon P S Segal 《The Journal of nervous and mental disease》1991,179(7):432-438
The purpose of the study was to compare an interview measure of quality of object relations to questionnaire and interview measures of recent interpersonal functioning with respect to the prediction of therapeutic alliance and psychotherapy outcome. The sample consisted of 64 patients who had received approximately 20 sessions of short-term individual psychotherapy within a controlled, clinical-trial investigation. Ratings of therapeutic alliance were provided independently by the patient and the therapist after each session. Outcome measures, which were provided by three sources (patient, therapist, and independent assessor), covered the areas of interpersonal functioning, psychiatric symptomatology, self-esteem, and life satisfaction. Quality of object relations, which characterizes the patient's lifelong pattern of relationships, was the best predictor. It was significantly related to patient-rated and therapist-rated therapeutic alliance and to patient improvement of both general symptomatology and specific target problems. The study also replicated previous studies that have reported significant relationships between therapeutic alliance and therapy outcome. The advantages of pretherapy predictors of therapy outcome, such as quality of object relations, are discussed. 相似文献
1000.
When human divers and experimental animals are exposed to an increasing environmental pressure, they develop the high pressure neurological syndrome (HPNS) characterized by electroencephalographic changes and sleep and behavioral disturbances. In rats, behavioral disturbances essentially include hyperlocomotor activity (HLA), tremor and myoclonia. Moreover, HLA has recently been demonstrated to be linked to a pressure-induced striatal increase of dopamine (DA). In these experiments, it was proposed to investigate in rats, at the behavioral level, the role of DA receptors in the occurrence of the pressure-induced DA disturbances. DA receptor agonists were found to induce no significant changes in the development of HLA, tremor, and myoclonia. Alternatively, HLA was found to be dramatically antagonized by the use of DA receptor antagonists (SCH 23390, sulpiride, and haloperidol), while tremor and myoclonia only decreased in SCH 23390 experiments. 相似文献