全文获取类型
收费全文 | 1074888篇 |
免费 | 71790篇 |
国内免费 | 1366篇 |
专业分类
耳鼻咽喉 | 15015篇 |
儿科学 | 34609篇 |
妇产科学 | 28627篇 |
基础医学 | 153410篇 |
口腔科学 | 29555篇 |
临床医学 | 94918篇 |
内科学 | 203634篇 |
皮肤病学 | 24392篇 |
神经病学 | 81540篇 |
特种医学 | 42964篇 |
外国民族医学 | 201篇 |
外科学 | 163092篇 |
综合类 | 21709篇 |
现状与发展 | 1篇 |
一般理论 | 263篇 |
预防医学 | 74616篇 |
眼科学 | 24538篇 |
药学 | 86106篇 |
7篇 | |
中国医学 | 2805篇 |
肿瘤学 | 66042篇 |
出版年
2019年 | 7757篇 |
2018年 | 11293篇 |
2017年 | 8907篇 |
2016年 | 10096篇 |
2015年 | 11260篇 |
2014年 | 15268篇 |
2013年 | 22204篇 |
2012年 | 30547篇 |
2011年 | 32292篇 |
2010年 | 18954篇 |
2009年 | 17817篇 |
2008年 | 29952篇 |
2007年 | 32069篇 |
2006年 | 32706篇 |
2005年 | 31039篇 |
2004年 | 29727篇 |
2003年 | 28557篇 |
2002年 | 27537篇 |
2001年 | 60023篇 |
2000年 | 61485篇 |
1999年 | 50937篇 |
1998年 | 12447篇 |
1997年 | 11003篇 |
1996年 | 11017篇 |
1995年 | 10321篇 |
1994年 | 9346篇 |
1993年 | 8862篇 |
1992年 | 37789篇 |
1991年 | 36275篇 |
1990年 | 35745篇 |
1989年 | 34286篇 |
1988年 | 30867篇 |
1987年 | 29987篇 |
1986年 | 28216篇 |
1985年 | 26450篇 |
1984年 | 19186篇 |
1983年 | 16113篇 |
1982年 | 8823篇 |
1979年 | 17029篇 |
1978年 | 11406篇 |
1977年 | 10233篇 |
1976年 | 8838篇 |
1975年 | 10071篇 |
1974年 | 11652篇 |
1973年 | 11276篇 |
1972年 | 10754篇 |
1971年 | 10095篇 |
1970年 | 9254篇 |
1969年 | 8939篇 |
1968年 | 7917篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
A L Usala I Wexler A Posch M K Gupta 《American journal of diseases of children (1960)》1992,146(9):1074-1077
OBJECTIVE--To determine the course of maternally derived elevations in thyrotropin-binding inhibitory immunoglobulins in a neonate. DESIGN--Case report. SETTING--University pediatric endocrinology clinic and endocrine immunology laboratory in Ohio. PARTICIPANTS--An infant with elevated thyrotropin levels but near-normal total thyroxine levels, and her mother. INTERVENTIONS--None. MEASUREMENTS/MAIN RESULTS--Thyroid hormone, thyrotropin, and thyrotropin-blocking immunoglobulin concentrations were serially measured in a woman and her infant, who was found to have elevated thyrotropin levels (234 mU/L) and borderline low thyroxine levels (95 nmol/L). As infant thyroxine concentrations remained normal (125 to 145 nmol/L), no thyroxine supplementation was given. Thyrotropin levels decreased concomitantly with thyrotropin-blocking inhibitory immunoglobulin levels, and normalized by day 56 of life. The apparent elimination half-life of thyrotropin-blocking immunoglobulins was 7.5 days. CONCLUSIONS--The observed parallel elimination kinetics suggest that the thyrotropin receptor antibody acts as a thyrotropin antagonist, resulting in compensatory thyrotropin elevations. The duration of such elevations may be predicted on the basis of such elimination. 相似文献
992.
M Arai H Kawada T Kaburagi N Sakai Y Kudou M Kawakami K Konno T Takizawa 《Nihon Kyōbu Shikkan Gakkai zasshi》1991,29(11):1457-1463
A 40-year-old man who lived in a wooden house built 30 years ago presented with complaints of fever, dry cough and dyspnea. Chest X-ray findings showed interstitial shadows throughout bilateral lung fields. After admission, high-dose administration of 3000 mg of methylprednisolone was performed because of deterioration of chest X-ray shadows and symptoms. In a week, clinical data and symptoms improved. Findings of BAL fluid on admission revealed a relative increase of lymphocytes, neutrophils and mast cells, and pathological findings of transbronchial lung biopsy revealed non-caseous granulation and alveolitis. Precipitating antibodies and indirect fluorescent antibodies against Trichosporon cutaneum and Cryptococcus neoformans had positive reactions and T. cutaneum was isolated and identified from the patient's house. A diagnosis of summer-type hypersensitivity pneumonitis was made according to the criteria advocated by Ando et al. This seemed to be a rare case of summer-type hypersensitivity pneumonitis prolonged after isolation from his normal living environment, successfully treated by high-dose administration of steroid. 相似文献
993.
The classical from of Wegener's granulomatosis (WG) is a necrotizing granulomatous angiitis that involves the upper and lower airways, and kidneys. A limited form of WG is characterized by pulmonary lesions identical to those of classical form WG without renal involvement. The authors report a case of limited form WG. A 58-year-old Japanese woman was admitted because of an abnormal pulmonary shadow. Pathological examination revealed granulomatous angiitis consistent with WG. No other organ involvement was found. The pulmonary shadow improved with cyclophosphamide therapy. The patient is now well and without evidence of exacerbation of the disease 18 month after the discharge. 相似文献
994.
995.
A Ueda K Aoyama T Ueda K Obama T Ueno S Hokama S Nomura 《British journal of industrial medicine》1992,49(7):499-506
The only workers presently exposed to bagasse dust in Japan are the employees of sugar refineries and lacquerware factories. A follow up study of six former cases of bagassosis from among the retired employees of a paper board factory, closed since 1973, showed that none of the subjects still had bagassosis. Examinations of 70 employees of a sugar refinery for allergic reactions also showed no case of bagassosis. Seven cases with suspicious shadows of bagassosis on chest radiographs and four cases with positive serum precipitin to stored bagasse were, however, found among those 70 subjects. The results show the disappearance of a past episode of bagassosis and the possibility of a new occurrence of bagassosis among the employees of sugar refineries and lacquerware factories in the near future in Japan. 相似文献
996.
997.
E K Lund W E Lee-Finglas S Southon J M Gee I T Johnson P M Finglas A J Wright 《European journal of clinical nutrition》1992,46(12):857-864
The relationship between dietary fat intake and fasting plasma lipid levels was assessed in 35 female and 19 male adolescents recruited from two local education authority schools in Norwich, UK. Dietary intakes were assessed using a 7-day weighed dietary record method, coupled with the collection of duplicate diets. Fat and energy intakes calculated using food composition tables were compared with values obtained by direct analysis of duplicate diets. Fasting plasma lipid levels (total, HDL and LDL cholesterol and triglycerides) were measured and compared with total dietary lipids and fatty acid intakes. The average proportion of energy consumed as fat was higher than is currently considered desirable but lower than previous studies have reported for adults. Mean serum total cholesterol values were 4.2 (SEM 0.1) mmol for females and 4.5 (SEM 0.2) mmol for males; this difference was not statistically significant. In male subjects the dietary fatty acid profiles were significantly correlated with several parameters of plasma lipid status which are thought to be risk factors for coronary heart disease, and in particular with the ratio of total:HDL cholesterol. 相似文献
998.
E M Mathus-Vliegen K van de Voorde A M Kok A M Res 《Journal of internal medicine》1992,232(2):119-127
Dexenfluramine, an effective and safe serotoninergic drug with anorectic and possible food-selection-tuning properties, was investigated in a placebo-controlled study of 1 year's duration in severe and refractory obesity. The aim of the study was to assess weight loss, and changes in cardiovascular risk factors, food intake and eating behaviour. Dexfenfluramine- and placebo-treated patients achieved a similar weight loss (greater than 10% of initial weight, by 39.5 and 30.0%, greater than 20% of initial overweight by 42.1% and 32.5% and greater than 10 kg by 41.4 and 33.3%, respectively, of the initial cohorts). Furthermore, the decreases in weight (10.7 vs. 8.0 kg), in body mass index (3.9 vs. 2.9 kg m2) and in waist/hip ratio (0.04 vs. 0.02) were not significantly different. After discontinuation of the drug, the increase in weight (2.8 vs. 1.0 kg) was significantly higher in the dexfenfluramine-treated group. Except for a borderline better effect on glucose of dexfenfluramine, both groups showed similar beneficial changes in food intake and cardiovascular risk factors. Eating behaviour in response to emotional and external stimuli was comparable in the two groups, but placebo-treated patients had to restrain their eating more in order to achieve the same weight loss. Notwithstanding the fact that weight losses and an associated amelioration of health-risk factors were of similar magnitude in dexfenfluramine- and placebo-treated patients, dexfenfluramine might have a useful role in promoting a less stressed adherence to prolonged restriction of energy intake in the severe and refractory obese subject. 相似文献
999.
Using immunologic techniques, we studied vinculin, a cytoskeletal protein associated with the membrane-skeleton of the muscle fiber. We examined muscle biopsies from five patients with Duchenne muscular dystrophy (DMD), two with Becker's muscular dystrophy (BMD), three normal human muscle samples, and four biopsies from disease control patients. All DMD patients showed patchy and low-intensity immunostain at the sarcolemma of most fibers and, by immunoblot analysis, the content of vinculin was 42 to 61% of control values. There was no significant vinculin deficiency in samples from patients with BMD and other disease controls. The data suggest that vinculin content is reduced only in muscle where dystrophin is absent or sparse. 相似文献
1000.
P J Thompson A Greenough H R Gamsu K H Nicolaides J Philpott-Howard 《Journal of medical microbiology》1992,36(2):117-120
The results of body fluid and surface cultures from 148 preterm infants less than 33 weeks gestational age obtained routinely on admission to a neonatal intensive care unit were reviewed. The aim was to determine the occurrence of congenital bacterial sepsis in this population and to examine whether surface cultures yielded information helpful in management. Gastric aspirate and umbilical, nasal and ear swabs were cultured and the results were compared to those of blood cultures. Nine infants (5.4%) had congenital bacterial sepsis diagnosed by positive blood cultures. Only the results of microscopy of gastric aspirate were available within hours of birth and before the results of blood culture. Microscopy of gastric aspirate, demonstrating pus cells, alone had a sensitivity of 0.86 in predicting congenital sepsis but a specificity of 0.49; the specificity, however, rose to 0.80 if both organisms and pus cells were observed on microscopy. Thus, only this combination was a useful pre-indicator of congenital sepsis. In infants who did not develop septicaemia, treatment was modified only if Streptococcus agalactiae was cultured from surface sites; in all such cases, the organism was grown from the ear swab. Our results demonstrate that congenital bacterial sepsis is common amongst very preterm infants admitted for neonatal intensive care but routine screening of surface cultures should be restricted to an ear swab only. 相似文献