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21.
Summary Nutrient intakes and selected blood and urinary constituents of 16 Navy servicemen were obtained before and during a period of 113 hours of physical activity, sleep deprivation, and psychological stress, to document the dietary adaptation of physically conditioned men to an extended period of hard physical work and other stresses. Food intakes were monitored by 1-day diet records prior to and by direct observation during the period. The factorial method was used to calculate energy expenditure. Carbohydrates provided 45 and 43% of the total energy intake before and during the experiment. Protein intakes and intakes of all the vitamins and minerals studied exceeded the Recommended Dietary Allowances, both before and during the period. Total energy intake averaged 18.7 MJ · d–1 before and 24.4 MJ · d–1 during the experiment. Body weight increased significantly by 2.7±0.4 kg (mean±s.e.) during the experiment (p< 0.0001). There was a significant correlation (r=0.74; p<0.001) between the change in body weight and urinary sodium from before to after the experiment suggesting that increased dietary sodium may have contributed to the weight gain. A significant increase in plasma volume (11.9±3.2%; p< 0.0003) provided further support that the observed weight gain was due to sodium intake rather than a positive energy balance. In conclusion, conditioned men increased food consumption adequately to meet increased energy demands.  相似文献   
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Objective

The purpose of this project was to develop an English-Russian Epidemiology Dictionary, which is needed for improved international collaboration in public health surveillance.

Introduction

As part of the US Department of Defense strategy to counter biological threats, the Defense Threat Reduction Agency’s Cooperative Biological Engagement Program is enhancing the capabilities of countries in the former Soviet Union (FSU) to detect, diagnose, and report endemic and epidemic, man-made or natural cases of especially dangerous pathogens. During these engagements, it was noted that Western-trained and Soviet-trained epidemiologists have difficulty, beyond that of simple translation, in exchanging ideas.The Soviet public health system and epidemiology developed independently of that of other nations. Whereas epidemiology in the West is thought of in terms of disease determinants in populations and relies on statistics to make inferences, classical Soviet epidemiology is founded on a more ecological view with the main focus on infectious diseases’ spread theory. Consequently many fundamental Soviet terms and concepts lack simple correlates in English and other languages outside the Soviet sphere; the same is true when attempting to translate from English to Russian and other languages of the FSU. Systematic review of the differences in FSU and Western epidemiologic concepts and terminology is therefore needed for strengthening understanding and collaboration in disease surveillance, pandemic preparedness, response to biological terrorism, etc.

Methods

Following an extensive search of the Russian and English literature by a working group of Western and FSU epidemiologists, we created a matrix containing English and Russian definitions of key epidemiologic terms found in FSU and Western epidemiology manuals and dictionaries, such as A Dictionary of Epidemiology (1), Epidemiology Manual (2) and many other sources. Particular emphasis was placed on terms relating to infectious disease surveillance, analysis of surveillance data, and outbreak investigation. In order to compare the definitions of each term and to elucidate differences in usage and existing gaps, all definitions were translated into English and Russian so that the definitions could be compared side by side and discussed by the working group.

Results

Six hundred and thirty one terms from 27 English and 51 Russian sources were chosen for inclusion based on their importance in applied epidemiology in either the West or the FSU. Review of the definitions showed that many terms within biosurveillance and infectious disease public health practice are used differently, and some concepts are lacking altogether in the Russian or English literature. Significant gaps in FSU epidemiology are in the areas of biostatistics and epidemiologic study designs. There are distinctive differences in FSU and Western epidemiology in the conceptualization and classification of disease transmission, surveillance practices, and control measures.

Conclusions

Epidemiologic concepts and definitions significantly differed in the FSU and Western literature. To improve biosurveillance and international collaboration, recognition of these differences must occur. Detailed analysis of epidemiology terminology differences will be discussed in the presentation and paper. Major limitations of the work were scarcity of prior research on the subject and lack of bilingual epidemiologists with the good understanding of FSU and Western approaches. A bilingual reference in the form of a dictionary will greatly improve mutual comprehension and collaboration in the areas of biosurveillance and public health practice.  相似文献   
23.
Sonographic appearance of aggressive angiomyxoma of the scrotum.   总被引:3,自引:0,他引:3  
Aggressive angiomyxoma (AAM) is a rare, locally infiltrative tumor that occurs almost exclusively in the pelvic and perineal regions of women of childbearing age. We report the unusual case of a 26-year-old man with an AAM presenting as a slowly enlarging scrotal mass. Gray-scale scrotal sonography demonstrated a well-demarcated, hypoechoic, extratesticular, extraepididymal mass with multiple thin, echogenic internal septa. The mass arose inferior to the left testicle and displaced the testicle cephalad. Color Doppler sonography revealed surrounding vascularity but no Doppler signals within the mass. The testicles and epididymides demonstrated normal echogenicity and vascularity. Histologic examination of the excised mass revealed a well-demarcated, nonencapsulated lesion composed of spindle-shaped cells in a myxoid background with a prominent vascular component.  相似文献   
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25.

Background  

Infectious gastrointestinal illness (IGI) outbreaks have been reported in U.S. Navy ships and could potentially have an adverse mission impact. Studies to date have been anecdotal.  相似文献   
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The uptake of zinc (Zn) into the plasma after the ingestion of 25 mg of Zn from multivitamin-mineral supplement was studied in 10 men during running (R) and control (C) conditions; the R was for 2 h at 60-65% of their maximal oxygen uptake. Subjects took the supplement with 200 ml of deionized water before the R or C (0-time). Blood was drawn before the Zn load and every 30 min for 3 h. By 2 h, plasma Zn concentrations had risen to values that were 151 +/- 7% and 149 +/- 5% of (0-time) R and C concentrations, respectively. Furthermore, the average rates of Zn uptake into the plasma did not differ between the R and C (4.4 vs 3.8 mumol.l-1.h-1) conditions. Finally, areas under the curve were not different (R: 13.2 +/- 1.8 mumol.l-1.3h-1; C: 11.5 +/- 1.5 mumol.l-1.3h-1). In summary, submaximal endurance running did not affect plasma Zn uptake and therefore absorption of Zn from a supplement taken just prior to exercise. The effect of chronic exercise on Zn absorption remains to be determined.  相似文献   
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Although studies with interleukin-1 receptor antagonist (IL-1ra) in animal models have shown that IL-1 contributes to mortality in sepsis, the mechanisms whereby IL-1 mediates lethal effects are not well established. A possible mechanism is that IL-1 enhances the activation and release of other inflammatory mediator systems such as coagulation, fibrinolysis, neutrophils, and secretory-type phospholipase A2 (sPLA2). We investigated this possibility by assessing the effect of intravenously injected recombinant human IL-1 alpha (rhIL-1 alpha) on these plasma parameters in baboons. In addition, we examined the course of these inflammatory parameters in baboons after a challenge with a lethal dose of Escherichia coli and while receiving a 24-hour constant infusion of IL-1ra or placebo. Intravenous administration of IL-1 alpha (10 micrograms/kg) induced the formation of thrombin, as evidenced by the appearance of thrombin-antithrombin III (TAT) complexes into the circulation (peak levels, 188 +/- 92 ng/mL at 2 hours), as well as the activation of fibrinolysis, assessed by circulating plasmin-alpha 2- antiplasmin complexes (PAP complexes; peak levels, 0.4% +/- 0.03% of fully activated plasma at 1 hour), the release of tissue-type plasminogen activator (t-PA; peak levels, 6 +/- 2 ng/mL at 2 hours), and its inhibitor, plasminogen activator inhibitor (PAI; peak levels, 724 +/- 246 ng/mL at 4 hours). Il-1 alpha administration also induced the release of sPLA2 (maximal levels, 336 +/- 185 ng/mL at 8 hours), but not degranulation of neutrophils. In the septic baboons, a significant reduction of the formation of thrombin (peak TAT levels decreased from 582 +/- 78 ng/mL to 219 +/- 106 ng/mL; P < .005), the release of t-PA (peak levels decreased from 37 +/- 11 ng/mL to 17 +/- 2 ng/mL; P < .001), and its inhibitor, PAI (peak levels decreased from 2,639 +/- 974 ng/mL to 1,110 +/- 153 ng/mL; P <.001), was observed in the group receiving IL-1ra compared to that receiving placebo. The release of neutrophilic elastase was also significantly attenuated in IL-1a-treated animals (peak levels, 1,024 +/- 393 and 655 +/- 104 ng/mL in control and treatment groups, respectively; P < .05). The difference between sPLA2 levels in both groups, although higher in the controls (maximal levels, 3,140 +/- 1,435 ng/mL in control v 2,217 +/- 1,375 ng/mL in IL-1ra-treated group), was not significant. Thus, IL-1 contributes to activation of various other mediator systems in severe sepsis in nonhuman primates. We propose that these effects may explain the lethal actions of IL-1 in this sepsis model and suggest a similar role for IL-1 in severe human sepsis.  相似文献   
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