全文获取类型
收费全文 | 1740篇 |
免费 | 140篇 |
国内免费 | 61篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 74篇 |
妇产科学 | 24篇 |
基础医学 | 266篇 |
口腔科学 | 28篇 |
临床医学 | 193篇 |
内科学 | 293篇 |
皮肤病学 | 16篇 |
神经病学 | 242篇 |
特种医学 | 121篇 |
外国民族医学 | 2篇 |
外科学 | 227篇 |
综合类 | 52篇 |
一般理论 | 9篇 |
预防医学 | 113篇 |
眼科学 | 34篇 |
药学 | 118篇 |
中国医学 | 2篇 |
肿瘤学 | 126篇 |
出版年
2022年 | 9篇 |
2021年 | 18篇 |
2020年 | 16篇 |
2019年 | 15篇 |
2018年 | 28篇 |
2017年 | 26篇 |
2016年 | 31篇 |
2015年 | 35篇 |
2014年 | 29篇 |
2013年 | 50篇 |
2012年 | 84篇 |
2011年 | 69篇 |
2010年 | 44篇 |
2009年 | 60篇 |
2008年 | 61篇 |
2007年 | 94篇 |
2006年 | 72篇 |
2005年 | 74篇 |
2004年 | 58篇 |
2003年 | 57篇 |
2002年 | 59篇 |
2001年 | 49篇 |
2000年 | 59篇 |
1999年 | 64篇 |
1998年 | 47篇 |
1997年 | 51篇 |
1996年 | 43篇 |
1995年 | 35篇 |
1994年 | 27篇 |
1993年 | 33篇 |
1992年 | 25篇 |
1991年 | 41篇 |
1990年 | 41篇 |
1989年 | 52篇 |
1988年 | 35篇 |
1987年 | 34篇 |
1986年 | 36篇 |
1985年 | 32篇 |
1984年 | 24篇 |
1983年 | 12篇 |
1982年 | 16篇 |
1981年 | 19篇 |
1980年 | 21篇 |
1979年 | 13篇 |
1978年 | 14篇 |
1977年 | 10篇 |
1976年 | 17篇 |
1974年 | 17篇 |
1972年 | 13篇 |
1971年 | 9篇 |
排序方式: 共有1941条查询结果,搜索用时 15 毫秒
1.
Confounders contributing to the reported associations of coffee or caffeine with disease 总被引:2,自引:0,他引:2
G B Schreiber M Robins C E Maffeo M N Masters A P Bond D Morganstein 《Preventive medicine》1988,17(3):295-309
The role of caffeine or coffee in causing or promoting the incidence of serious disease is equivocal. Two design factors may account for the discrepancies in reported findings on the effects of coffee drinking: (a) imprecision of measurement and (b) confounding variables. A study of 2,714 white U.S. adults disclosed that, of 32 risk factors analyzed by linear and logistic regression, only sex and cigarette smoking were found to be important potential confounders of caffeine and coffee intake. Partial R2 values of the other 30 risk factors were relatively small and were inconsistent for each sex. It is unlikely that any of these factors could explain any of the reported associations between caffeine or coffee consumption and certain diseases. However, certain weak associations with caffeine or coffee intake should be included in the study design when they are known to be risk factors of a disease under investigation. These factors for men are dietary fat intake, vitamin C intake, and body mass index; and for women are vitamin use, alcohol intake, stress, and perceived health status. 相似文献
2.
3.
Religious orientation, aging, and blood pressure reactivity to interpersonal and cognitive stressors
Kevin S. Masters Ph.D. Robert D. Hill Ph.D. John C. Kircher Ph.D. Tera L. Lensegrav Benson M.S. Jennifer A. Fallon M.S. 《Annals of behavioral medicine》2004,28(3):171-178
Background: Research on religion and health suggests general health benefits for those who are more religiously involved. Particular
aspects of religiosity that may influence this finding, however, have not been sufficiently investigated.Purpose: This study was designed to explore the relationship between religious orientation (intrinsic, extrinsic) and blood pressure
reactivity among older (over 60 years) and younger (18–24 years) adults exposed to two qualitatively different laboratory
stressors (cognitive, interpersonal).Methods:Participants were categorized as exhibiting either a predominately intrinsic or extrinsic religious orientation based on scores
on the Religious Orientation Scale. They were subsequently exposed (in counterbalanced order) to two laboratory stressors
that varied in terms of whether an interpersonal confrontation was involved. Measures of blood pressure were obtained at baseline
and during stressor presentation.Results: Analyses indicated that older extrinsically religious individuals demonstrated exaggerated reactivity compared to younger
participants and older intrinsically religious individuals. Older intrinsically religious participants did not differ from
younger persons. Similar results were found for analysis of baseline data. Extrinsic participants had greater reactivity during
the interpersonal confrontation condition than did intrinsic individuals.Conclusions: These findings suggest that religious orientation may be an important variable to study regarding cardiovascular reactivity
in, particularly, older adults.
This research was supported in part by National Institute on Aging Grant 1 R03 AG 18554-01. A previous version of this article
was presented in August 2002 as a Citation Paper at the 110th Annual Convention of the American Psychological Association,
Chicago.
We thank Timothy W. Smith, James A. Blumenthal, Carl E. Thoresen, and Edward M. Heath for their assistance throughout this
project. We also thank Llewellyn Jones and Jodi Hildabrandt for their efforts in collecting data. 相似文献
4.
A 5-Year experience of 51 endoscopic transthoracic dorsal sympathectomies for idiopathic palmar hyperhidrosis in 26 patients is presented. Fifty-two percent complained of excessive sweating over their hands, 28% of axillary sweating and 20% over both areas, with a mean duration of 10 years. The second, third and fourth thoracic ganglia and their interconnecting fibres on the affected side were ablated using diathermy cautery. Over a mean follow up time of 26 months, this procedure was successful in curing or improving intractable sweating in 92%. However, axillary sweating was less well controlled than in the palms with 20% of patients describing residual wetness in the axilla. Compensatory sweating (75%) and gustatory sweating (48%) were the commonest side effects; despite this, most patients were satisfied with the functional and cosmetic outcome. Other complications included a temporary Horner's syndrome in one patient, a pneumothorax in the immediate post-operative period in another and a unilateral non-infective reactionary pleural effusion in a third. Two patients developed recurrence of palmar hyperhidrosis within 6 months of surgery. One has been successfully treated by re-operation on the affected side. All patients complained of mild to moderate interscapular chest pain which was easily controlled by non-steroidal anti-inflammatory agents, and resolved within 7–10 days post-operatively. The technique of endoscope transthoracic sympathectomy is effective, relatively simple to perform and usually requires only an overnight stay. It is recommended as the surgical treatment of choice for upper limb hyperhidrosis unresponsive to conservative measures. 相似文献
5.
Homicide inflicts massive injury upon the intrapsychic and interpersonal realities of the surviving kin of murder victims. A New York City pilot program of outreach and counselling to 1182 families of Brooklyn homicide victims suggests that surviving kin undergo the symptoms of traumatic stress disorder. Recovery is prolonged by knowledge that the perpetrator is usually alive and in some cases unpunished, by repetitive confrontations with the criminal justice system and by the multiple losses endured: loss of a family member, loss of illusions of safety and invulnerability, loss of a sense of trust in the surrounding community, and loss of a belief system. Effective help to survivors requires interventions that respond to all aspects of the survivors' losses. 相似文献
6.
7.
Rick A LaCaille M Scott DeBerard Lara J LaCaille Kevin S Masters Alan L Colledge 《The spine journal》2007,7(3):266-272
BACKGROUND CONTEXT: Results of lumbar fusion surgery have been mixed and procedures are costly. Interbody cage lumbar fusion (ICLF) has been advanced to improve arthrodesis and clinical outcomes; however, little attention has been given to ICLF costs or potential predictors of these expenses. PURPOSE: To depict medical and compensation costs associated with ICLF in a Utah cohort of patients receiving workers' compensation as well as to investigate predictors of costs. STUDY DESIGN/SETTING: A retrospective-cohort research design was used involving completion of presurgical and postsurgical medical record reviews and accrual of medical and compensation costs. Presurgical variables included in a regression model were presurgical spinal pathophysiology rating, obesity, and litigation status. PATIENT SAMPLE: Forty-three consecutive patients who were compensated by the Workers' Compensation Fund of Utah and underwent ICLF. OUTCOME MEASURES: Total accrued compensation and medical costs. METHODS: A retrospective review of presurgical variables and total accrued compensation and medical costs was conducted. RESULTS: Multiple regression analysis indicated that nonpathophysiological factors predicted compensation costs (lawyer involvement [beta=0.40]; obesity [beta=0.34]). Specifically, compensation for those with versus without lawyers was $41,657 versus $24,837, and for those who were obese versus nonobese was $46,152 versus $28,168. Arthrodesis was correlated with medical costs (r=-0.47, p=.002), with incurred costs for patients achieving solid fusion versus pseudarthrosis equaling $38,881 versus $71,655, respectively. CONCLUSIONS: Considerable costs were associated with ICLF, particularly for those who were obese, involved in litigation, or failed to achieve solid fusion. With regard to compensation costs, the findings support the importance of assessing nonpathophysiological factors in spinal fusion patients. 相似文献
8.
Post-infectious bronchiolitis obliterans: clinical, radiological and pulmonary function sequelae 总被引:6,自引:0,他引:6
Background. There are few data on clinical, chest radiograph (CXR) or pulmonary function sequelae in children with post-infectious bronchiolitis
obliterans (BO) (pulmonary crepitations, abnormalities on CXR, CT, nuclear medicine scans, or bronchography, with a history
of past pulmonary infection and in the absence of other underlying pathology). Objective. To analyse the methodology of diagnosis, long-term clinical imaging and pulmonary function sequelae of post-infectious BO
in children. Materials and methods. Imaging (CXRs, CT and nuclear lung scans) and clinical histories of 19 children were analysed. Results. Clinical follow-up (mean 6.8 years), revealed a high incidence of continuing problems (asthma and bronchiectasis). Fixed
airway obstruction was the most common pulmonary function sequela. The sequelae on follow-up (mean 5.8 years) CXR were classified
into five patterns which are illustrated: unilateral hyperlucency of an enlarged lung/part of lung; complete collapse of the
affected lobe; unilateral hyperlucency of a small or normal-sized lung; bilateral hyperlucent lungs and a mixed pattern of
persistent collapse, hyperlucency and peribronchial thickening. Conclusion. Long-term observations in children with post-infectious BO should be undertaken to detect bronchiectasis and obstructive
airway disease. Sequelae evident on CXR, other than those previously described, can be found. Bronchography and/or lung biopsy
are not usually required for the diagnosis of post-infectious BO.
Received: 15 January 1997 Accepted: 23 June 1997 相似文献
9.
Background
There is currently an unprecedented expressed need and demand for estimates of maternal mortality in developing countries. This has been stimulated in part by the creation of a Millennium Development Goal that will be judged partly on the basis of reductions in maternal mortality by 2015. 相似文献10.
The IgG GEL test was compared with the LISS tube test (L?w and Messeter's low-ionic-strength saline) for antibody identification. The suitability of red blood cells (RBCs) pretreated with ficin, dithiothreitol (DTT), or chloroquine diphosphate (CDP) also was assessed for use in the GEL test. In addition, time-in-motion studies were performed comparing GEL (12 panels per batch) with polyethylene glycol (PEG) tube tests (3 panels per batch). In 57 antibody identification studies, there were 63 GEL+ LISS+, 2 GEL+ LISS-, and 6 GEL-LISS+ antibodies. Among the GEL+ LISS+ antibodies were 19 that yielded stronger reactions in GEL than in LISS; by virtue of their specificity, 14 of these are considered potentially significant: D, 5 E, 2 e, 2 Jka, 2 S, K, and Fya. There were 38 antibodies that yielded equivalent results by both methods, including 31 that are considered potentially significant. Of six antibodies with significantly greater reactivity in LISS, there were three anti-Rh and three that are considered harmless with respect to transfusion management. The two GEL+ LISS- antibodies (anti-Jkb) were potentially significant. GEL- LISS+ reactions involved only harmless antibodies. Of the 50 antibodies of potential significance, GEL yielded equivalent or superior results in 47 (94%) instances. Additionally, GEL failed to detect 6 of 21 harmless antibodies. Expected results were obtained with normal serum or plasma and antibodies of known specificity in tests with RBCs treated with ficin, DTT, or CDP. Hands-on-time required for each GEL panel was 2 to 21/2 minutes compared with 12 minutes for PEG. These data document the suitability of GEL for use in antibody identification studies. 相似文献