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991.
In this study we examined the relationship between characteristics of the diurnal pattern of salivary free cortisol concentration and ultrasound (US) measures of bone in premenopausal women. Subjects were 36 healthy, eumenorrhoeic, nonsmoking women mean age (SE) 30.9 (1.3) years. Saliva samples were collected on awakening and 10, 20, 30, 120, 240, and 600 minutes thereafter. Calcaneal broadband ultrasonic attenuation (BUA) and speed of sound (SOS) were determined. Mean (SE) salivary cortisol concentration was 4.7 (0.5) nmol/l on awakening, peaked at 8.6 (0.9) nmol/l 30 min later, and declined to a trough of 2.3 (0.2) nmol/l 600 min after awakening. BUA and SOS were significantly associated with cortisol 0 and 30 min after awakening (r = 0.40 and 0.40 for BUA and 0.33 and 0.37 for SOS, respectively, with body mass included as covariate). Cortisol levels 240 and 600 min after awakening were not significantly associated with bone variables. Women above the median for peak (30 min after awakening) cortisol had significantly higher BUA and SOS than those below the median [BUA 51.8 (1.0) vs 47.4 (1.5) dB/MHz, P = 0.017; SOS 1554.0 (2.5) vs 1546.4 (1.5) m/sec, P = 0.008]. A high peak in cortisol following awakening was associated with higher US measures of bone in healthy premenopausal women. This finding suggests the possibility that diurnal variation in cortisol may have a role in bone metabolism.  相似文献   
992.
Hallux limitus is one of the most prevalent, debilitating disorders of the first metatarsophalangeal joint, and it has many proposed etiologies. This article reviews these etiologies, focusing primarily on the pes planus foot. The pes planus foot type is often associated with symptomatic hallux limitus and the accessory navicular. This article discusses this correlation, although a causal relationship has not been proven. The prevalence and classification of the accessory navicular are also discussed. Clinical cases involving symptomatic hallux limitus occurring concomitantly with an accessory navicular are reviewed, including radiographic findings, symptoms, and surgical treatment.  相似文献   
993.
OBJECTIVE: To assess the nutritional status of female competitive figure skaters during preseason, competitive season, and off-season. SUBJECTS: Eighteen female competitive figure skaters, age range 14 to 16 years, from the New England region. STATISTICS: Data was analyzed by repeated measures analysis of variance, Duncan Multiple Range Tests, one-sample t tests, and confidence intervals. DESIGN: Nutrient intakes were determined from 3-day diet records. Body composition was assessed through heights, weights, and underwater weighing. Blood samples were drawn for analysis of selected indexes of nutritional status. RESULTS: Height and weight did not differ significantly among the seasons. Body fat was 1.1 kg higher off-season compared with preseason. Energy intake over the 3 seasons did not vary significantly (mean preseason: 1,678 kcal/day; competitive season, 1,630 kcal/day; off-season: 1,673 kcal/day) (P>.05). During the competitive season 78%, 50%, and 44% of the skaters had intakes less than 67% of RDA for folate, iron, and calcium, respectively. Most of the biochemical indexes of nutritional status were within normal limits. CONCLUSIONS: The results indicate that teenage female skaters have relatively low energy intake and inadequate intakes of certain nutrients, which may account for some of the observed seasonal variations in blood markers of nutritional status. These findings point to the need for nutrition education for these athletes, especially during their competitive season when nutritional status may be compromised.  相似文献   
994.
BACKGROUND: Estimates of body-composition change in older adults are mostly derived from cross-sectional data. OBJECTIVE: We examined the natural longitudinal patterns of change in fat-free mass (FFM) and fat mass (FM) in older adults and explored the effect of physical activity, weight change, and age on these changes. DESIGN: The body composition measured by hydrodensitometry and the level of sports and recreational activity (SRA) of 53 men and 78 women with a mean (+/-SD) initial age of 60.7 +/- 7.8 y were examined on 2 occasions separated by a mean (+/-SD) time of 9.4 +/- 1.4 y. RESULTS: FFM decreased in men (2.0% per decade) but not in women, whereas FM increased similarly in both sexes (7.5% per decade). Levels of SRA decreased more in men than in women over the follow-up period. Baseline age and level of SRA were inversely and independently associated with changes in FM in women only. Neither age nor level of SRA was associated with changes in FFM in men or women. Weight-stable subjects lost FFM. FFM accounted for 19% of body weight in those who gained weight, even in the presence of decreased levels of SRA. Loss of FFM (33% of body weight) was pronounced in those who lost weight, despite median SRA levels >4184 kJ/wk. CONCLUSIONS: On average, FM increased; however, the increase in women was attenuated with advancing age. The decrease in FFM over the follow-up period was small and masked the wide interindividual variation that was dependent on the magnitude of weight change. The contribution of weight stability, modest weight gains, or lifestyle changes that include regular resistance exercise in attenuating lean-tissue loss with age should be explored.  相似文献   
995.
The effect of early posthatch starvation on myonuclear apoptosis was examined in chickens. Male broiler chickens were or were not provided feed for the first 3-d posthatch. Subsequently, all chickens were provided feed for an additional 4-d posthatch. Chickens were killed at 3- and 7-d posthatch, and the pectoralis thoracicus was harvested, fixed and embedded in paraffin. Muscle sections were labeled with the terminal deoxynucleotidyl transferase histochemical staining technique to identify apoptotic nuclei. At 3- and 7-d posthatch, there was a significantly (P < 0.05) smaller myofiber cross-sectional area for the starved compared with the fed chickens. A larger proportion (P < 0.05) of apoptotic nuclei relative to total nuclei was observed in the starved compared to the fed chickens killed at 3-d posthatch, but the proportion of apoptotic nuclei relative to total nuclei did not differ (P > 0.05) between the starved and fed chickens killed at 7-d posthatch. It appears that apoptosis is a mechanism contributing to the smaller myofiber size observed when feed is not provided early posthatch.  相似文献   
996.
997.
The broad aim of the research presented here was to define the constituents and indicators of quality of life (QoL) in older age, in order to offer a more multidimensional and useful model of quality of life, based on the perspectives of older people themselves. This paper focuses on the extent to which self-evaluations of global QoL are influenced by health, psychological and social variables, and social circumstances. It reports the results of a national survey of the quality of life in people aged 65 and over, living at home in Britain. Multiple regression analysis with the self-evaluation of quality of life rating as the dependent variable showed that the overall model (Model 9) of QoL indicators explained 26.7% of the variance in quality of life ratings. This is sizeable given the amorphous nature of this concept. The main independent predictors of self-rated global quality of life were: social comparisons and expectations, personality and psychological characteristics (optimism-pessimism), health and functional status and personal and neighbourhood social capital. These variables explained the highest proportion of the variance between groups in their quality of life ratings. Socio-economic indicators contributed relatively little to the model.  相似文献   
998.
999.
We characterized prescribing in Connecticut's State public mental health system to assess the feasibility of implementing an evidence-based medication algorithm. Medication records for a random sample of outpatients with diagnoses of schizophrenia spectrum disorders showed prescribing patterns similar to the entire United States. The base rate of changing antipsychotic medications was moderate. Over half of patients received decanoate medications, polypharmacy was nontrivial, and there was variability in prescribing patterns across physicians. Caucasian patients were more likely to receive an atypical antipsychotic and less likely to have a decanoate medication, and Latino patients were less likely to change medications. Because the base rate of changing medications was moderate and a considerable proportion of patients were prescribed newer antipsychotic medications, introducing a research-derived medication algorithm with newer atypical antipsychotics as first line agents may fit well with current practice. Further, implementing such an algorithm may reduce racial and ethnic disparities in prescribing patterns.  相似文献   
1000.
Accuracy of needle placement into the intra-articular space of the knee   总被引:10,自引:0,他引:10  
BACKGROUND: To achieve their potential therapeutic benefit, hyaluronic acid derivatives should be injected directly into the knee joint space and not into the anterior fat pad or the subsynovial tissues. In the absence of a knee effusion, reproducible needle placement into the intra-articular space presents a challenge to the clinician. METHODS: The accuracy of needle placement was assessed in a prospective series of 240 consecutive injections in patients without clinical knee effusion. The injections were performed by one orthopaedic surgeon using a 2.0-in (5.1-cm) 21-gauge needle through three commonly employed knee joint portals: anteromedial, anterolateral, and lateral midpatellar. Accuracy rates for needle placement were confirmed with fluoroscopic imaging to document the dispersion pattern of injected contrast material. RESULTS: Of eighty injections performed through an anterolateral portal, fifty-seven were confirmed to have been placed in the intra-articular space on the first attempt (an accuracy rate of 71%). Sixty of eighty injections performed through an anteromedial approach were intra-articular on the first attempt (75% accuracy rate), as were seventy-four of eighty injections performed through a lateral midpatellar portal (93% accuracy rate). CONCLUSIONS: Using real-time fluoroscopic imaging with contrast material, we demonstrated the difficulty of accurately placing a needle into the intra-articular space of the knee when an effusion is not present. This study revealed that a lateral midpatellar injection (an injection into the patellofemoral joint) was intra-articular 93% of the time and was more accurate than injections performed by the same orthopaedic surgeon using either of the other two portals. This study highlights the need for clinicians to refine injection techniques for delivering intra-articular therapeutic substances that are intended to coat the articular surfaces of the knee joint.  相似文献   
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