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91.
Infectious episodes in runners before and after the Los Angeles Marathon 总被引:20,自引:0,他引:20
D C Nieman L M Johanssen J W Lee K Arabatzis 《The Journal of sports medicine and physical fitness》1990,30(3):316-328
An epidemiologic study of Los Angeles Marathon (LAM) applicants was conducted to investigate the relationship between self-reported infectious episodes (IE), training data, and LAM participation. Eight days before the LAM, 4926 of 12,200 applicants were randomly selected, and sent a pilot-tested four page questionnaire, which was received 7 days after the LAM. The 2311 respondents were found to be 2.0 yr older and 7.6 min faster than other LAM finishers (p less than .01). Univariate and multivariate analyses (logistic regression) were conducted to test the relationship between IE and km/wk of running (6 total categories). The final model tested controlled for age, marital status, reported sickness in other members of the runner's home, perceived feelings of stress in response to personal training regimens, and the suppressive effect of sickness on regular training. In runners training greater than or equal to 97 vs less than 32 km/wk, the odds ratio (OR) for IE during the 2 month period prior to the LAM was 2.0 (95% confidence interval (CI) 1.2-3.4). A test for trend showed an increase in OR with increase in km/wk category (p = .04) which was largely explained by the increased odds of reported sickness in the greater than or equal to 97 km/wk category. Of the 1828 LAM participants without IE before the LAM, 236 (12.9%) reported IE during the week following the LAM vs 3 of 134 (2.2%) similarly experienced runners who did not participate, OR = 5.9 (95% CI 1.9-18.8). These data suggest that runners may experience increased odds for IE during heavy training or following a marathon race. 相似文献
92.
Diane E. Butterworth DHSc MPH Rd avid C. Nieman DrPH Regina Perkins Beverly J. Warren PhD Ruth G. Dotson MA 《Journal of the American Dietetic Association》1993,93(6)
This study examined the relationship between moderate exercise training (five 30- to 40-minute sessions per week for 12 weeks at 60% of heart rate reserve) and changes in nutrient intake in a group of 30 sedentary elderly women aged 67 to 85 years. Subjects were placed randomly into two groups (those who walked and those who did calisthenics) and were followed for 12 weeks. Measurements were done at three times (baseline, 5 weeks, and 12 weeks). Dietary intake was based on 7-day food records. The 12-week walking program resulted in a significant (12.6%) improvement in maximum oxygen consumption (
2max) but no change in body weight or skinfold thicknesses compared with the calisthenics program. Despite the improvement in cardiorespiratory fitness, no significant group × time interaction effects were observed for most of the nutrient intake variables tested. To test the effects of high levels of physical activity on nutrient intake, cross-sectional comparisons were made at baseline between highly conditioned and sedentary elderly women. The highly conditioned elderly women had higher energy and nutrient intakes, especially when expressed on a weight-adjusted basis. However, no differences in measures of dietary quality were found. Dietitians should not expect spontaneous improvement in either the quantity or quality of nutrient intake by elderly women who adopt a moderate exercise program. Although nutrient intake was greater in highly conditioned elderly women, their level of fitness and physical activity may be beyond the reach of many elderly women. 相似文献
93.
D C Nieman J L Haig K S Fairchild E D De Guia G P Dizon U D Register 《The American journal of clinical nutrition》1990,52(4):640-645
Twenty-one mildly obese women were fed a 1268-kcal lactovegetarian diet for 5 wk. Subjects were randomly divided into either an exercise (Ex) or a nonexercise (Nex) group. The Ex group walked at 60% heart-rate reserve (134 +/- 2 bpm; mean +/- SEM) during 45-min sessions, five times per week. Although exercise improved estimated maximum oxygen consumption (VO2max; 20.9 +/- 3.2% vs 2.1 +/- 3.4% in Ex vs Nex, respectively), changes in total body, lean body, and fat weight did not differ significantly between groups. Total body weight decreased 5.5 +/- 0.6 and 5.6 +/- 0.2 kg in Ex and Nex, respectively. Statistical analysis revealed significant differences in the pattern of change between groups for serum high-density-lipoprotein cholesterol (HDL-C; F[2,38] = 5.93, P = 0.006) but not for total cholesterol (TC), low-density-lipoprotein cholesterol, triglycerides, or glucose. Change in diet quality and body weight were found to account fully for the 12.7 +/- 1.9% decrease in TC. When change in dietary quality and body weight are equated in a group of mildly obese women, the effect of moderate exercise training on indices of serum lipid and lipoprotein is limited to HDL-C. 相似文献
94.
95.
96.
A cause of electrosurgical burns in surgical procedures is faulty active leads. A survey of faults and modes of failures are reported. The design of a meter is given for use by a sterilizing department to enable leads to be checked. Using the criterion of two times the original resistance, 35 cables were found to be defective out of a population of about 200 cables. About half of these cables transmitted radio frequency (RF) power inefficiently: often power was intermittent and hot spots would develop. The commonest mode of failure was a break between the socket and the wire at the forceps end. Rejection criteria are reviewed and we suggest a resistance less than 0.3 omega. 相似文献
97.
D C Nieman K M Sherman K Arabatzis B C Underwood J C Barbosa M Johnson T D Shultz J Lee 《International journal of sports medicine》1989,10(4):243-251
The purpose of this study was to investigate hematological, anthropometric, and metabolic differences in elderly women who were similar in most respects except for choice of diet. Nineteen vegetarian (V) and 12 non-vegetarian (NV) elderly women (mean ages 72.3 +/- 1.4 and 69.5 +/- 1.0 years, respectively) were recruited based on several selection criteria including race, religion, education, Quetelet Index, absence of major chronic disease and use of medications, physical activity, and geographic area. Average years of adherence by V and NV groups to dietary regimens were 46.3 +/- 3.3 and 69.6 +/- 1.0, respectively; Hematological comparisons revealed that the V elderly women had significantly lower glucose (4.60 +/- 0.09 vs 5.13 +/- 0.11 mmol/L), low-density lipoprotein cholesterol (3.14 +/- 0.19 vs 4.09 +/- 0.27 mmol/L) and total cholesterol levels (5.41 +/- 0.20 vs 6.48 +/- 0.29 mmol/L) than the NV elderly women (P less than 0.01) for each. The V elderly women tended to have less body fat and midupper arm muscle area than the NV. No differences between groups were found in a variety of metabolic and electrocardiographic parameters during graded maximal treadmill testing except for lower heart rates in the V women. VO2max was not significantly different between the V and NV elderly women (23.8 +/- 1.5 vs 21.9 +/- 0.8 ml.kg-1.min-1, respectively). In summary, when healthy elderly V women are compared with closely matched NV peers, the vegetarian diet is associated with several benefits, primarily lower blood glucose and lipid levels, but not greater functional capacity. 相似文献
98.
99.
Eleven marathon runners (42.7 +/- 2.1 yrs, 54.2 +/- 1.8 ml.kg-1.min-1) and nine sedentary controls (44.2 +/- 1.2 yrs, 33.3 +/- 1.1 ml.kg-1.min-1) were studied during 30 min of rest, a graded maximal treadmill test using the Balke protocol, and 45 min of recovery to determine the effects of training and acute exercise on complement and immunoglobulin levels. Three baseline and five recovery blood samples were obtained in addition to repeated 5-min samples during exercise. Data for the exercise period were analyzed using a multiple regression approach to repeated measures ANOVA to allow comparison between groups on a percent VO2max basis. Groups did not differ during any of the three phases for IgG, IgA, or IgM. Resting levels of complement C3 (0.89 +/- 0.05 vs 1.27 +/- 0.10 g/L, P less than 0.001) and C4 (0.19 +/- 0.02 vs 0.29 +/- 0.03 g/L, P less than 0.001) were significantly lower in athletes than in controls. Exercise complement C3 [F(1,18) = 14.1, P = 0.001] and C4 [F(1,18) = 7.6, P = 0.013], and recovery complement [F(1,18) = 19.4, P less than 0.001] and C4 [F(1,18) = 13.5, P = 0.002] were also lower in the athletes than in sedentary controls. Acute increases during exercise were not associated with changes in catecholamines or cortisol. These data suggest that blood concentrations of C3 and C4, but not IgG, IgA, or IgM, are decreased during rest, graded maximal exercise, and recovery in marathon runners in comparison with sedentary controls. 相似文献
100.
van Uden CJ Nieman FH Voss GB Wesseling G Winkens RA Crebolder HF 《BMC health services research》2005,5(1):27