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991.
Alcohol consumption within elite sport has been continually reported both anecdotally within the media and quantitatively in the literature. The detrimental effects of alcohol on human physiology have been well documented, adversely influencing neural function, metabolism, cardiovascular physiology, thermoregulation and skeletal muscle myopathy. Remarkably, the downstream effects of alcohol consumption on exercise performance and recovery, has received less attention and as such is not well understood. The focus of this review is to identify the acute effects of alcohol on exercise performance and give a brief insight into explanatory factors.  相似文献   
992.
993.
AIM: To assess the relationship between preoperative computed tomography (CT) and postoperative pathological measurements of esophageal tumor length and the prognostic significance of CT tumor length data.METHODS: A retrospective study was carried out in 56 patients who underwent curative esophagogastrectomy. Tumor lengths were measured on the immediate preoperative CT and on the post-operative resection specimens. Inter- and intra-observer variations in CT measurements were assessed. Survival data were collected.RESULTS: There was a weak correlation between CT and pathological tumor length (r = 0.30, P = 0.025). CT lengths were longer than pathological lengths in 68% (38/56) of patients with a mean difference of 1.67 cm (95% CI: 1.18-2.97). The mean difference in measurements by two radiologists was 0.39 cm (95% CI: -0.59-1.44). The mean difference between repeat CT measured tumor length (intra-observer variation) were 0.04 cm (95% CI: -0.59-0.66) and 0.47 cm (95% CI: -0.53-1.47). When stratified, patients not receiving neoadjuvant chemotherapy showed a strong correlation between CT and pathological tumor length (r = 0.69, P = 0.0014, n = 37) than patients that did (r = 0.13, P = 0.43, n = 19). Median survival with CT tumor length > 5.6 cm was poorer than with smaller tumors, but the difference was not statistically significant.CONCLUSION: Esophageal tumor length assessed using CT does not reflect pathological tumor extent and should not be the only modality used for management decisions, particularly for planning radiotherapy.  相似文献   
994.
PurposeThere is no consensus on what constitutes adequate negative margins in breast-conserving therapy (BCT). We review the evidence on surgical margins in BCT for early-stage invasive breast cancer.MethodsMeta-analysis of studies reporting local recurrence (LR) relative to quantified final microscopic margin status and the threshold distance for negative margins. The proportion of LR was modelled using random effects logistic meta-regression.ResultsBased on 21 studies (LR in 1,026 of 14,571 subjects) the odds of LR were associated with margin status [model 1: odds ratio (OR) = 2.02 for positive/close versus negative; model 2: OR = 1.80 for close versus negative, 2.42 for positive versus negative (P < 0.001 both models)] but not with margin distance [1 mm versus 2 mm versus 5 mm (P > 0.10 both models)], adjusting for median follow-up time. However, there was weak evidence in both models that the odds of LR decreased as the threshold distance for declaring negative margins increased. This bordered significance in model 2 [OR for 1 mm, 2 mm, 5 mm: 1.0, 0.75, 0.51 (P = 0.097 for trend)], and was not significant in model 1 [OR for 1 mm, 2 mm, 5 mm: 1.0, 0.85, 0.58 (P = 0.11 for trend)] but was evident when one study (of women ? 40 years) was excluded from this model [OR for 1 mm, 2 mm, 5 mm: 1.0, 0.72, 0.52 (P = 0.058 for trend)]: this trend was rendered insignificant by adjustment for the proportion of subjects receiving a radiation boost or the proportion of subjects receiving endocrine therapy.ConclusionsMargin status has a prognostic effect in all women treated for invasive breast cancer; increasing the threshold distance for declaring negative margins is weakly associated with reduced odds of LR, however adjustment for covariates (adjuvant therapy) removes the significance of this effect. Adoption of wider margins, relative to narrower widths, for declaring negative margins is unlikely to a have substantial additional benefit for long-term local control in BCT.  相似文献   
995.

BACKGROUND:

In late reproductive‐aged breast cancer survivors, there is a need for real‐time biomarkers of postchemotherapy ovarian function. The objective was to determine whether antimullerian hormone (AMH) and inhibin B are such biomarkers. The authors tested whether AMH and inhibin B were impacted by breast cancer treatment by comparing cancer survivors to age‐matched control women and determined the association between these hormones and postchemotherapy menstrual pattern.

METHODS:

Breast cancer patients (n = 127) with American Joint Committee on Cancer stage I to III disease who were premenopausal at diagnosis were enrolled postchemotherapy and observed. The primary endpoint was chemotherapy‐related amenorrhea (CRA) (≥12 months of amenorrhea after chemotherapy). Matched pair analyses compared AMH, inhibin B, and follicle‐stimulating hormone (FSH) levels between cancer and age‐matched control subjects. Associations between hormones, CRA status, and change in CRA status over time were assessed.

RESULTS:

The median age of the patients at chemotherapy was 43.2 years (range, 26.7‐57.8 years). At enrollment, median follow‐up since chemotherapy was 2.1 years, and 55% of subjects had CRA. Compared with age‐matched controls, cancer subjects had significantly lower AMH (P = .004) and inhibin B (P < .001) and higher FSH (P < .001). AMH (P = .002) and inhibin B (P = .001) were found to be significantly associated with risk of CRA, even after controlling for FSH. AMH was significantly lower (P = .03) and FSH was significantly higher (P = .04) in menstruating subjects who developed subsequent CRA.

CONCLUSIONS:

AMH and inhibin B are 2 additional measures of postchemotherapy ovarian function in late reproductive‐aged breast cancer survivors. With further research and validation, these hormones may supplement limited current tools for assessing and predicting postchemotherapy ovarian function. Cancer 2010. © 2009 American Cancer Society.  相似文献   
996.
997.
Cancer patients often report impaired sleep quality. Impaired sleep quality may be due to increased levels of sleep-mediating cytokines resulting from cancer treatment. Exercise may have a positive influence on sleep-mediating cytokines, such as interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and soluble tumor necrosis factor-alpha receptor (sTNF-R), which may improve sleep quality. This two-arm pilot study compared the influence of a home-based exercise intervention with standard care/control on sleep quality and mediators of sleep. Breast and prostate cancer patients (n = 38) beginning radiation therapy were randomized to a 4-week exercise program or no exercise arm. Global sleep quality, subjective sleep quality, sleep latency, sleep duration, sleep efficiency, sleep disturbances, use of sleep medication, and daytime dysfunction were assessed with the Pittsburgh Sleep Quality Index. IL-6, TNF-α, and sTNF-R were measured before and after intervention. There was a greater improvement in sleep quality in the exercise group from pre- to postintervention, although the difference was not significant. Additionally, there were associations between IL-6 and sleep efficiency and duration, suggesting that regulation of sleep-mediating cytokines by exercise may mediate improvements in sleep-quality components.  相似文献   
998.
ObjectiveTo assess the iodine status and knowledge and practices related to iodine nutrition of Australian women during pregnancy.MethodsA cross-sectional study was conducted at a public antenatal clinic in the Illawarra region of New South Wales. One hundred thirty-nine pregnant women across all trimesters provided a spot urine sample (n = 110) and completed a short questionnaire (n = 139) in English. Iodine status was based on World Health Organization/International Committee for the Control of Iodine Deficiency Disorders urine iodine concentration (UIC) categories.ResultsMedian UIC was 87.5 μg/L (interquartile range 62); only 14.5% of participants had an adequate UIC value ≥150 μg/L. Fifteen percent of women had very low UIC values (<50 μg/L), whereas 45.5% had values in the 50- to 99-μg/L range. Knowledge of the adverse health effects of an inadequate iodine intake was poor. Approximately half the participants were able to indicate good dietary sources of iodine, such as fish (58%) and iodized salt (51%). However, a high level of confusion regarding other foods was evident. Only a small number of participants (11%) reported that they had intentionally changed their diet to increase iodine intake during pregnancy, but 59% indicated supplement use, of which 35% contained iodine. Those who were taking supplements that contained iodine had significantly higher UIC levels (139.1 μg/L) than those who were not (90.8 μg/L, P < 0.05).ConclusionPublic health strategies, including nutritional education and supplementation, are urgently required to improve the iodine status of pregnant women. Currently, no readily accessible information on iodine is available to women attending antenatal clinics in Australia.  相似文献   
999.
1000.
A large proportion of four million neonatal deaths occur each year during the first 24 hours of life. Research is particularly needed to determine the efficacy of interventions during the first 24 hours. Large cadres of community-based workers are required in newborn-care research both to deliver these interventions in a standardized manner in the home and to measure the outcomes of the study. In a large-scale community-based efficacy trial of chlorhexidine for cleansing the cord in north-eastern rural Bangladesh, a two-tiered system of community-based workers was established to deliver a package of essential maternal and newborn-care interventions and one of three umbilical cord-care regimens. At any given time, the trial employed approximately 133 community health workers--each responsible for 4-5 village health workers and a population of approximately 4,000. Over the entire trial period, 29,760 neonates were enrolled, and 87% of them received the intervention (their assigned cord-care regimen) within 24 hours of birth. Approaches to recruitment, training, and supervision in the study are described. Key lessons included the importance of supportive processes for community-based workers, including a strong training and field supervisory system, community acceptance of the study, consideration of the setting, study objectives, and human resources available.  相似文献   
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