全文获取类型
收费全文 | 14987篇 |
免费 | 1051篇 |
国内免费 | 36篇 |
专业分类
耳鼻咽喉 | 191篇 |
儿科学 | 402篇 |
妇产科学 | 252篇 |
基础医学 | 2058篇 |
口腔科学 | 405篇 |
临床医学 | 1929篇 |
内科学 | 2622篇 |
皮肤病学 | 161篇 |
神经病学 | 1506篇 |
特种医学 | 523篇 |
外科学 | 1665篇 |
综合类 | 173篇 |
一般理论 | 8篇 |
预防医学 | 1749篇 |
眼科学 | 338篇 |
药学 | 1034篇 |
中国医学 | 23篇 |
肿瘤学 | 1035篇 |
出版年
2023年 | 119篇 |
2022年 | 167篇 |
2021年 | 334篇 |
2020年 | 228篇 |
2019年 | 332篇 |
2018年 | 392篇 |
2017年 | 296篇 |
2016年 | 334篇 |
2015年 | 386篇 |
2014年 | 480篇 |
2013年 | 712篇 |
2012年 | 1059篇 |
2011年 | 1134篇 |
2010年 | 556篇 |
2009年 | 539篇 |
2008年 | 914篇 |
2007年 | 950篇 |
2006年 | 990篇 |
2005年 | 957篇 |
2004年 | 818篇 |
2003年 | 785篇 |
2002年 | 775篇 |
2001年 | 163篇 |
2000年 | 121篇 |
1999年 | 148篇 |
1998年 | 145篇 |
1997年 | 144篇 |
1996年 | 110篇 |
1995年 | 102篇 |
1994年 | 86篇 |
1993年 | 93篇 |
1992年 | 93篇 |
1991年 | 114篇 |
1990年 | 90篇 |
1989年 | 96篇 |
1988年 | 77篇 |
1987年 | 69篇 |
1986年 | 67篇 |
1985年 | 75篇 |
1984年 | 68篇 |
1983年 | 83篇 |
1982年 | 79篇 |
1981年 | 84篇 |
1980年 | 68篇 |
1979年 | 55篇 |
1978年 | 43篇 |
1977年 | 49篇 |
1976年 | 49篇 |
1974年 | 42篇 |
1972年 | 37篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Terry Reed 《Clinical genetics》1991,39(5):391-395
Evidence from the literature is reviewed to suggest that when fingertip dermal ridge patterns in chromosomal deletion syndromes are characteristic of the opposite spectrum of the developmental scale from patterns found in cases trisomic for the same chromosomal region, the association may be a consequence of loci with growth regulatory functions. Evidence is presented that DNA markers at 18q21 should be the first candidate sequences to be used to test this hypothesis in families with fingertip arches segregating in an apparent autosomal dominant fashion. 相似文献
22.
J D Coie J E Lochman R Terry C Hyman 《Journal of consulting and clinical psychology》1992,60(5):783-792
Two large cohorts of Black 3rd-grade children from low-income families were followed into early adolescence. Adjustment at the end of the 1st year of middle school was assessed by teacher and parent ratings and by adolescent self-reports. Childhood peer social status predicted parent-reported externalized and internalized disorder and self-reported internalized disorder. Childhood aggression predicted self-reported externalized and internalized disorder and parent-reported externalized disorder. Teacher ratings of school adjustment were predicted by aggression, rejection, and sex of the child. Consensus judgments of poor adjustment were predicted by both aggression and peer rejection, with sex moderating the effect of peer rejection. Both childhood aggression and peer rejection appear to be significant predictors of adolescent disorder, with each making a predictive contribution uniquely its own. 相似文献
23.
Conor Armstrong Séamus S. Napier Robert C. Boyd Terry A. Gregg 《Journal of oral pathology & medicine》2004,33(4):246-248
Histological examination of the deciduous teeth in two cases of segmental odontomaxillary dysplasia (SOMD) showed fibrous enlargement of the pulps, an irregular pulp/dentine interface displaying many pseudoinclusions and pulp stones. There were tubular defects in the coronal dentine from pulp horn to cusp tip, an irregular tubular structure to the circumpulpal dentine of the apical half, a focally deficient odontoblast layer and widespread external resorption. Together with the clinical features of unilateral maxillary enlargement, upper alveolar expansion in the distal segment, increased spacing and delayed eruption of the deciduous molars and absence of premolar teeth, these histological appearances allow distinction of this condition from fibrous dysplasia (FD), segmental hemifacial hypertrophy (SHH) and regional odontodysplasia (ROD). 相似文献
24.
Terry R. McGuire 《Behavior genetics》1992,22(4):453-467
Chromosome analysis has been widely used as a first step in eclucidating the genetic architecture of several behaviors ofDrosophila melanogaster. These chromosome studies have generally used incomplete designs or fairly simple statistical analyses. Here I reanalyze two data sets on geotaxis from Pyle (1978) and Ksander (1966) using a biometrical genetic design. Results from the biometrical genetic reanalysis suggest that individual differences in geotaxis might be due to genes on all three major chromosomes which show extensive epistatic interactions. 相似文献
25.
L Ho-Terry G M Terry P Londesborough K R Rees F Wielaard A Denissen 《Journal of medical virology》1988,24(2):175-182
The efficacy of nucleic acid hybridization for the diagnosis of rubella infection in experimental and clinical materials was compared with immunoblot and virus isolation techniques. Our results showed that nucleic acid hybridization is specific and rapid but gives false-negative results when compared with conventional virus isolation in some experimental although not in clinical materials so far examined. For this reason, a failure to demonstrate rubella virus in fetal specimens by this method alone cannot yet be taken as a sole criterion for ruling out fetal rubella infection. 相似文献
26.
27.
Whereas water loss in land living animals occurs continuously, water intake takes place discontinuously. At the normal operating set point of plasma osmolality, urine is more concentrated than plasma due to secretion of vasopressin. Thus animals operate around a state of mild dehydration. As water loss occurs, the severity of dehydration and thirst increase in intensity and at some point water intake occurs. Sufficient water is consumed to return plasma osmolality to the normal operating set point. Food intake and water balance are interdependent as food provides the osmoles which determine obligatory renal solute excretion. When dry food with the same osmotic content was substituted for canned food (water content 74%), dogs increased water intake from 24.2 +/- 4.3 to 62.2 +/- 8.8 ml/kg. Urine output and urine osmolality were unchanged, as under conditions of normal hydration, near maximal urine concentration is achieved. Changing water intake is the only available variable to maintain water balance. During water deprivation, the major renal mechanism appears to be natriuresis. In rehydration, satiety mechanisms ensure appropriate water intake and renal sodium conservation restores sodium balance. 相似文献
28.
29.
Introduction: Occupational contact dermatitis (OCD) is very common in the printing industry due to contact with chemicals, paper, and wet work. It can be avoided by adequate protective measures, but the effectiveness of intervention depends heavily on the employer's and employee's awareness of this health risk.
Objectives: The study aimed to collect information on the knowledge, attitudes and beliefs of print workers about the risk of OCD and methods of prevention.
Methods: A series of focus groups were held with print workers, health and safety officers and managers to discuss their awareness of dermal risk factors, risk behaviour at work, attitudes to health and safety and options on possible preventive measures. A number of companies were also visited to observe, overtly and covertly, the normal work practices.
Results: OCD was not perceived to be either a major problem or a health and safety priority. There was general agreement about the processes and work practices that could cause skin problems. However, work practices varied considerably and did not always reflect this awareness. There was general concern about the type and availability of personal protective equipment, especially gloves and after‐work skin cream. The provision of an occupational health service was generally felt to be inadequate, and no company had a policy in place that specifically addressed skin care.
Conclusions: These findings highlight the urgency to intensify health and safety education on skin care within the printing industry. Recommendations were developed for the evaluation of a series of risk reduction strategies. 相似文献
Objectives: The study aimed to collect information on the knowledge, attitudes and beliefs of print workers about the risk of OCD and methods of prevention.
Methods: A series of focus groups were held with print workers, health and safety officers and managers to discuss their awareness of dermal risk factors, risk behaviour at work, attitudes to health and safety and options on possible preventive measures. A number of companies were also visited to observe, overtly and covertly, the normal work practices.
Results: OCD was not perceived to be either a major problem or a health and safety priority. There was general agreement about the processes and work practices that could cause skin problems. However, work practices varied considerably and did not always reflect this awareness. There was general concern about the type and availability of personal protective equipment, especially gloves and after‐work skin cream. The provision of an occupational health service was generally felt to be inadequate, and no company had a policy in place that specifically addressed skin care.
Conclusions: These findings highlight the urgency to intensify health and safety education on skin care within the printing industry. Recommendations were developed for the evaluation of a series of risk reduction strategies. 相似文献
30.
Lorraine N Clark Eneli Haamer Helen Mejia-Santana Juliette Harris Suzanne Lesage Alexandra Durr Sabine Janin Bs Katja Hedrich Elan D Louis Lucien J Cote Howard Andrews Stanley Fahn Cheryl Waters Blair Ford Steven Frucht William Scott Christine Klein Alexis Brice Hanno Roomere Ruth Ottman Karen Marder 《Movement disorders》2007,22(7):932-937
Parkin mutations account for the majority of familial and sporadic early onset Parkinson's disease (EOPD) cases with a known genetic association. More than 100 mutations have been described in the Parkin gene that includes homozygous, compound heterozygous, and single heterozygous mutations. We have designed a Parkin mutation genotyping array (gene chip) that includes published Parkin sequence variants and allows their simultaneous detection. The chip was validated by screening 85 PD cases and 47 controls previously tested for Parkin mutations. Similar genotyping microarrays have been developed for other genetically heterogeneous diseases including age-related macular degeneration. Here, we show the utility of a genotyping array for Parkinson's disease by analysis of 60 subjects from the Genetic Epidemiology of Parkinson Disease (GEPD) study that includes 15 early-onset PD case probands and 45 relatives. 相似文献