全文获取类型
收费全文 | 11047篇 |
免费 | 681篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 126篇 |
儿科学 | 407篇 |
妇产科学 | 224篇 |
基础医学 | 1328篇 |
口腔科学 | 127篇 |
临床医学 | 1627篇 |
内科学 | 1893篇 |
皮肤病学 | 135篇 |
神经病学 | 966篇 |
特种医学 | 209篇 |
外科学 | 1242篇 |
综合类 | 207篇 |
一般理论 | 10篇 |
预防医学 | 1362篇 |
眼科学 | 415篇 |
药学 | 712篇 |
中国医学 | 13篇 |
肿瘤学 | 738篇 |
出版年
2023年 | 47篇 |
2022年 | 67篇 |
2021年 | 131篇 |
2020年 | 112篇 |
2019年 | 168篇 |
2018年 | 188篇 |
2017年 | 164篇 |
2016年 | 158篇 |
2015年 | 188篇 |
2014年 | 275篇 |
2013年 | 448篇 |
2012年 | 650篇 |
2011年 | 694篇 |
2010年 | 406篇 |
2009年 | 352篇 |
2008年 | 662篇 |
2007年 | 686篇 |
2006年 | 697篇 |
2005年 | 701篇 |
2004年 | 637篇 |
2003年 | 706篇 |
2002年 | 622篇 |
2001年 | 194篇 |
2000年 | 213篇 |
1999年 | 222篇 |
1998年 | 143篇 |
1997年 | 118篇 |
1996年 | 105篇 |
1995年 | 97篇 |
1994年 | 89篇 |
1993年 | 98篇 |
1992年 | 128篇 |
1991年 | 147篇 |
1990年 | 114篇 |
1989年 | 110篇 |
1988年 | 118篇 |
1987年 | 106篇 |
1986年 | 82篇 |
1985年 | 83篇 |
1984年 | 76篇 |
1983年 | 68篇 |
1982年 | 52篇 |
1981年 | 66篇 |
1980年 | 44篇 |
1979年 | 63篇 |
1978年 | 54篇 |
1977年 | 46篇 |
1976年 | 39篇 |
1973年 | 35篇 |
1972年 | 46篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
The sodium, potassium and creatinine contents of three non-consecutive 24-h urine samples collected by 34 selected adult individuals (10 m; 24 f) living in Cork City were determined. The pooled mean 24-h excretion of sodium and potassium in collections adjudged to be complete were 152 mmol and 78 mmol, respectively. There was no significant difference between group average weekday and weekend-day excretion of Na or K, for either males or females. This suggests that weekend 24-h urinary collections, which most subjects find more convenient, are suitable for studies of sodium and potassium intakes of groups. The ratios of intra- to inter-individual variation for 24-h urinary sodium were 1.4 and 2.1 for males and females, respectively. The corresponding ratios for 24-h urinary potassium were 6.6 for males and 4.9 for females. These ratios indicated that there were large individual day-to-day variations in urinary sodium and potassium excretion in this group. It was estimated that a sample size of 35-60 individuals would be required to estimate group mean sodium and potassium intakes by means of single 24-h urine collections. 相似文献
2.
Aaron H. Burstein Pharm.D. William G. Reiss Pharm.D. Eric Kantor B.A. Gail D. Anderson Ph.D. 《Pharmacotherapy》1998,18(6):1271-1276
Study Objective . To characterize cytochrome P450 (CYP) 3A4 activity in premenopausal and postmenopausal women by evaluating the urinary 6-β-hydroxycortisokcortisol ratio. Design . Prospective study. Subjects . Thirteen premenopausal and 13 postmenopausal women who were healthy and not receiving drugs known to affect CYP3A4 activity. Interventions . Beginning on day 2 of menses, premenopausal women collected first morning urine samples every other day for a complete menstrual cycle. Postmenopausal women collected first morning urine every other day for 28 days. Measurements and Main Results . Mean weekly 6-β-hydroxycortisol:cortisol ratios did not differ during the phase (week) of the menstrual cycle. Daily ratios did not differ in postmenopausal women. No difference between premenopausal and postmenopausal women was found on comparing overall median ratios. Conclusion . Cytochrome P450 3A4 activity as measured by 6-β-hydroxy cortisol:cortisol ratio did not differ by week of menstrual cycle, suggesting no menstrual cycle-related changes. Menopause does not appear to be associated with differences in CYP3A4 activity, compared with premenopause. 相似文献
3.
4.
No impact of repeated endoscopic screens on gastric cancer mortality in a prospectively followed Chinese population at high risk. 总被引:6,自引:0,他引:6
B Riecken R Pfeiffer J L Ma M L Jin J Y Li W D Liu L Zhang Y S Chang M H Gail W C You 《Preventive medicine》2002,34(1):22-28
BACKGROUND: Gastric cancer (GC) is the leading cause of cancer deaths in China. Our study prospectively evaluated the impact of repeated endoscopic screens on GC mortality in a high-risk population in China. METHODS: Between 1989 and 1999, a population-based gastroscopic screening was conducted in 4,394 residents of Linqu County, China, a region with the highest rates of GC worldwide. Residents ages 35 to 64 years received initial gastroscopies with biopsies in 1989. Repeated endoscopies were performed in 1994 and 1999. Cancer occurrences and deaths were actively monitored throughout the entire period until July 2000. Mortality from GC was compared with expected values based on mortality rates obtained for Linqu in the 1990-1992 Chinese Cancer Mortality Survey. RESULTS: Between March 1989 and July 2000, 39,303 person-years were accumulated; 85 new GCs occurred, 29 (34.5%) were in early stage. Fifty-eight cases (68%) were identified at one of the screens. The number of observed deaths from GC (37) was close to the expected (36.8). The standardized mortality ratio was 1.01 (95% CI 0.72-1.37) for the entire cohort, 1.13 (95% CI 0.77-1.57) for males, and 0.65 (95% CI 0.26-1.32) for females. CONCLUSIONS: Despite high population coverage with repeated screens, no reduction in GC mortality was observed in this high-risk population in China. 相似文献
5.
6.
Trotter's syndrome is a clinical triad of unilateral deafness, neuralgia affecting branches of the trigeminal nerve, and defective mobility of the soft palate, which is caused by malignant tumors involving the lateral pharyngeal recess (Rosenmüller's fossa). It is an ominous presentation, which can masquerade as dental or masticatory pain. Computerized tomography (CT) can be used not only to explain the anatomic basis of Trotter's syndrome but also to determine the extent and distribution of the malignant tumor involved. The advantages of CT over conventional radiography are illustrated by a case of adenoid cystic carcinoma that presented as Trotter's syndrome. Perineural invasion by tumor is shown on the gross level for the first time with CT, and important diagnostic considerations, which may aid in the early diagnosis of future cases, are discussed. 相似文献
7.
8.
INTELLECTUAL FUNCTIONS OF PATIENTS WITH CHILDHOOD-ONSET EPILEPSY 总被引:21,自引:2,他引:19
Ernst A. Rodin Steve Schmaltz Gail Twitty 《Developmental medicine and child neurology》1986,28(1):25-33
The intellectual functions of 64 epileptic patients who had had an initial evaluation between five and 16 years of age, including the WISC, were re-evaluated after a period of at least five years. In general the seizure states had improved, and 50 per cent were in remission for between two and eight years. All but four were still taking at least one anticonvulsant drug. WISC IQ estimates showed a slight decrease. Verbal and performance areas could be differentially affected, and a gain in one could be offset by a loss in the other, so the Full-scale IQ might not be a reliable measure of day-to-day performance. Those whose seizures remained uncontrolled had a statistically significant decrease in performance IQ, whereas in general it was stable or increased for patients in remission. There was evidence that decreased IQ indicated slower mental growth rather than loss of previously acquired function. Phenobarbital but not phenytoin levels were inversely correlated with IQ, suggesting that the upper limit of the 'therapeutic range' of phenobarbital may already be toxic with regard to learning abilities. To optimize an epileptic child's functioning in school and to prevent long-term intellectual problems, it is advisable that IQ testing should be part of the routine initial evaluation, and that drug levels should be checked at regular intervals. 相似文献
9.
Daniel A. Monti Marie E. Stoner Gail Zivin Martha Schlesinger 《Journal of cancer survivorship》2007,1(2):161-166
Introduction As many as one quarter of all cancer survivors report traumatic stress symptoms from cancer-related experiences. While the
majority of these patients do not meet the criteria for posttraumatic stress disorder (PTSD), there is growing evidence that
subsyndromal symptoms can significantly contribute to functional impairment and negative health outcomes. Treatment options
for the hallmark symptoms of traumatic stress—unpleasant, intrusive thoughts and avoidant behaviors—have not been well investigated
for the cancer survivorship population.
Materials and methods Seven female cancer survivors with traumatic stress symptoms from cancer-related experiences and no other major psychopathology,
were enrolled to receive three sessions of Neuro-Emotional Technique (NET), a brief, targeted treatment that combines traditional
desensitization principles with complementary modalities.
Results Psychological outcome measures (Impact of Event Scale (IES) and Subjective Units of Distress (SUD) and physiological measures
(Heart Rate (HR) and Skin Conductance Level (SCL) demonstrated the following changes: 71% on IES, 88% SUD, 74% on HR, and
65% on SCL following the intervention. Statistically significant changes were observed for all four parameters, and effect
size g for proportion improved were 0.50 each for IES, SUD, and HR, and 0.20 for SCL.
Conclusions These cases suggest feasibility of the NET intervention for cancer-related traumatic stress and the potential for change in
symptoms and physiological reactivity. Further investigation is needed to determine the specific and long-term effects of
such an approach.
Implications for cancer survivors Traumatic stress from cancer-related experiences might represent a constellation of symptoms that are amenable to brief, targeted
interventions.
This study was supported by the O.N.E. Research Foundation 相似文献
10.