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961.
'Reverse white-coat hypertension' in older hypertensives   总被引:6,自引:0,他引:6  
OBJECTIVES: The role of ambulatory blood pressure monitoring (ABPM) in the elderly is unclear. This study has examined differences between clinic and ambulatory blood pressure (BP) in a large cohort of older hypertensives, with particular respect to the factors influencing the direction and magnitude of this difference. DESIGN: The Second Australian National Blood Pressure Study (ANBP2) is a general practice-based randomized-outcome trial in 6083 older hypertensives treated with an angiotensin-converting enzyme (ACE) inhibitor or diuretic-based regimen. Before starting treatment a subset of 713 patients (age range 65-83 years) had a 'successful' 26-hour ambulatory blood pressure recording with a SpaceLabs 90207 recorder. RESULTS: Average clinic BP (+/- SD) was 167 +/- 12/90 +/- 8 mmHg. Average daytime ambulatory BP was 157 +/- 15*/89 +/- 10* mmHg and night ambulatory BP was 137 +/- 16+/74 +/- 10+ mmHg (different from clinic BP: *P < 0.01;from daytime ambulatory BP: +P < 0.001). Twenty-one to 45% of all patients had higher daytime systolic or diastolic ambulatory BP than clinic readings, with smoking, previous treatment for hypertension and lower clinic BP being the main predictors of this 'reverse white-coat effect'. CONCLUSIONS: Although mean daytime ambulatory blood pressures were lower than clinic readings in this large cohort of untreated older hypertensives, a substantial proportion showed the reverse of the so-called 'white-coat effect'. These findings identify the important role for ABPM in the elderly, not only for avoiding overtreatment in those with typical 'white-coat hypertension' but also for ensuring adequate treatment is given to those with the reverse of this phenomenon.  相似文献   
962.
963.
BACKGROUND: The Institute of Medicine (IOM) recommends that normal-weight women (BMI (body mass index) of 19.8-26.0) gain 25-35 lb (11.4-15.9 kg) during pregnancy, and that overweight women (BMI of 26.1-29.0) gain 15-25 lbs (6.8-11.4 kg). A significant number of normal-weight women and an even greater proportion of overweight women exceed these guidelines, which increases postpartum weight retention and may contribute to the development of obesity. OBJECTIVE: To determine whether a stepped care, behavioral intervention will decrease the percentage of women who gain more than the IOM recommendation. DESIGN: Randomized controlled trial comparing a stepped-care behavioral intervention with usual care. Women (n=120) who had a BMI>19.8, age>18 and <20 weeks gestation were recruited from a hospital-based clinic serving low-income women and randomized by race and BMI category to the intervention or control group. The intervention group received education about weight gain, healthy eating, and exercise and individual graphs of their weight gain. Those exceeding weight gain goals were given more intensive intervention. Women were followed through pregnancy to their first postpartum clinic visit. The main outcome measure was weight gain during pregnancy categorized as above the IOM recommendations vs below or within the IOM recommendations. RESULTS: The intervention significantly decreased the percentage of normal-weight women who exceeded the IOM recommendations (33 vs 58%, P<0.05). There was a non-significant (P=0.09) effect in the opposite direction among overweight women (59% of intervention and 32% of control gained more than recommended). Postpartum weight retention was strongly related to weight gain during pregnancy (r=0.89). CONCLUSIONS: The intervention reduced excessive weight gain during pregnancy among normal weight women.  相似文献   
964.
What forces are propelling the healthcare industry's prolonged period of change? How are these forces shaping the future of HIM? In this article, investigators from the Center for Health Workforce Studies examine the roots of the work force shortage and reveal trends that will continue to influence the industry.  相似文献   
965.
PURPOSE: To discover sequence alterations in the TIGR/MYOC gene associated with primary open-angle glaucoma (POAG) in Chinese subjects. METHODS: Two hundred one unrelated Chinese patients with POAG and 291 unrelated individuals without glaucoma, aged 50 years or more, were screened for sequence alterations in the TIGR/MYOC gene by polymerase chain reaction, conformation sensitive gel electrophoresis, and DNA sequencing. Up to 111 more control subjects were screened for some of the alterations. RESULTS: Fourteen sequence variants that lead to amino acid changes were identified. Seven were novel: Pro16Leu, Ala17Ser, Leu95Pro, Leu215Pro, Glu300Lys, Glu414Lys, and Tyr471Cys. Of these, Glu300Lys and Tyr471Cys were found only in POAG. Arg46Stop was found in 4 patients with POAG (2.0%) and 9 of 402 control subjects (2.2%); one control subject was homozygous. IOP showed a trend (P = 0.11) toward a decrease of 1.5 mm Hg among the control subjects, with Arg46Stop compared with matched control subjects without Arg46Stop. Gly12Arg occurred four times as frequently in control subjects as in patients, but the difference was not statistically significant. CONCLUSIONS: Gly12Arg might be negatively associated with POAG, suggesting a protective effect. Three patients with POAG had a sequence change not found in control subjects, for a frequency of possible disease-causing TIGR/MYOC mutations of 1.5% (95% confidence interval [CI] = 0.3%-4.3%). Arg46Stop occurred with similar frequency in patients with POAG and control subjects, suggesting that the reduced amount of TIGR/MYOC predicted to result from this truncation does not dramatically increase or decrease risk of glaucoma.  相似文献   
966.
967.
目的:研究他克林的双体衍生物双(7)他克林对东莨菪碱引起的大鼠记忆障碍的影响.方法:采用大鼠Moris水迷宫固定平台的程序研究空间记忆.以他克林为对照药.结果:东莨菪碱(03mg·kg-1,ip)使大鼠到达平台的潜伏期明显长于生理盐水对照组.双(7)他克林(035μmol·kg-1,ig或ip)和他克林(852μmol·kg-1ig;426μmol·kg-1ip)均可对抗东莨菪碱导致的空间记忆障碍;在灌胃及腹腔注射途径下,双(7)他克林的效价,分别强于他克林24及12倍.结论:双(7)他克林明显改善东莨菪碱导致的空间记忆障碍,其作用强于他克林.  相似文献   
968.
We report on a 37-year-old woman who developed a desmoid tumor over the left chest within the field of previous radiotherapy for carcinoma of the breast. She had a history of bilateral sequential carcinoma of the breasts (a right-breast lesion followed by a left-breast lesion) and underwent bilateral mastectomy and adjuvant radiotherapy, with adjuvant chemotherapy given only to the right-breast cancer. Possible causal factors and treatment options for such tumors are highlighted. This case illustrates the importance of histologic confirmation for clinically suspicious local recurrence in patients with a history of breast cancer.  相似文献   
969.
OBJECTIVE: Young adults frequently experiment with vegetarian and weight-loss diets. Comparisons of their experiences on these two different diets may help in the development of approaches to improve long-term adherence to weight-loss regimens. In the current study vegetarian and weight-loss diets were compared on how long and how strictly they were followed, and reasons why they were initiated and discontinued. RESEARCH METHODS AND PROCEDURES: From 428 college students surveyed, four groups were delineated: 1) 59 participants had been following a vegetarian diet but not a weight-loss diet (Vegetarian), 2) 117 participants had tried a weight-loss diet but not a vegetarian diet (Weight Loss), 3) 133 participants had followed both a vegetarian and a weight-loss diet (Both), and 4) 119 participants had not tried either diet (Neither). RESULTS: Differences were examined by comparing the Vegetarian and Weight-Loss groups as well as by comparing the two diets within the Both group. Duration of the vegetarian diet was much greater than the weight-loss diet; most participants in the Vegetarian group (62%) remained on their diet for more than 1 year, whereas the majority of the Weight-Loss participants (61%) followed their diet for 1 to 3 months. Similar results were found when comparing the two diets within the Both group. How strictly the two diets were followed, however, did not differ. Analyses revealed that reasons for discontinuing a diet varied; participants were more likely to cite boredom as a reason for discontinuing a weight-loss diet than a vegetarian diet (53% vs. 5% between groups and 30% vs. 10% within the Both group). DISCUSSION: The longer duration of the vegetarian diet relative to the weight-loss diet warrants further investigation. Results could possibly be applied to behavioral weight-loss treatment to improve long-term maintenance.  相似文献   
970.
Physical activity and long-term maintenance of weight loss   总被引:6,自引:0,他引:6  
To examine the effect of exercise on the long-term maintenance of weight loss, two types of literature were reviewed--correlational studies of predictors of long-term weight loss, and randomized trials comparing diet, exercise, and the combination of diet plus exercise. Both literatures were striking in the consistency with which activity emerged as a determinant of long-term maintenance of weight loss. The benefits of exercise for long-term weight maintenance were observed with different types of populations, diets, and exercise interventions. Several possible explanations for these positive effects of diet plus exercise are presented, and suggestions made for future research on ways to maximize the benefit of this approach to weight control. Since adherence to exercise may ultimately prove to be the cornerstone for long-term weight maintenance, studying ways to improve exercise adherence is recommended.  相似文献   
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