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991.
The presence of cadmium (Cd), lead (Pb) and mercury (Hg) was investigated in fish and seafood products collected from the FAO Major Fishing Area 34, Eastern Central Atlantic. Samples were purchased from different retail outlets in Italy. Samples were selected so as to assess human exposure through diet. Metals were detected by Q-ICP-MS and Hg-AAS. All the metal concentrations detected were largely below the maximum levels (MLs) established by the European Union. The exposure assessment was undertaken by matching the concentration of Cd, Pb and total Hg in fish and other seafood products selected purposed according to Italian consumption data. The estimated weekly intakes (EWIs) for the evaluated elements related to the consumption of fish and other seafood products by the median of the Italian total population accounted for 14%, 2% and 14% of the standard tolerable weekly intake (TWI) for Cd and Hg as well as the provisional tolerable weekly intake (PTWI) for Pb, respectively.  相似文献   
992.
The assessment of nutritional intakes during hospitalization is crucial, as it is known that nutritional status tends to worsen during the hospital stay, and this can lead to the negative consequences of malnutrition. International guidelines recommend the use of parenteral nutrition (PN) in hypophagic, non-surgical patients at nutritional risk, with contraindications to enteral nutrition. However, to date, there are no published data regarding either energy intake or objective measurements associated with it in this patient population. The aim of the present exploratory methodological study was to evaluate whether phase angle (PhA) and handgrip strength normalized for skeletal muscle mass (HG/SMM) are sensitive early markers of energy intake in hypophagic, non-surgical patients at nutritional risk, with contraindications to enteral nutrition. We evaluated 30 eligible patients, who were treated with personalized dietary modifications and supplemental PN for at least one week during hospitalization. In a liner regression model adjusted for age, gender, basal protein intake and the basal value of each variable, a trend toward improvement of PhA and preservation of HG/SMM was observed in patients satisfying the estimated calorie requirements (N = 20), while a significant deterioration of these parameters occurred in those who were not able to reach the target (N = 10). The mean adjusted difference and 95% CI were +1.4° (0.5–2.3) (p = 0.005) for PhA and +0.23 (0.20–0.43) (p = 0.033) for HG/SMM. A significant correlation between PhA and HG/SMM variations was also observed (r = 0.56 (95% CI, 0.23–0.77); p = 0.0023). PhA and HG/SMM were able to distinguish between hypophagic, non-surgical patients at nutritional risk who satisfied their estimated caloric requirements and those who did not after a one-week personalized nutritional support. Clinical studies are warranted, in order to verify these preliminary observations and to validate the role of PhA variations as early markers of anabolic/catabolic fluctuations.  相似文献   
993.
Lesions centered on the area postrema (AP) and adjacent nucleus of the solitary tract (AP/mNTS-lesions) are reported to result in increased consumption of highly palatable diets. Recent studies suggest that neuropeptide Y (NPY) may cause a preference for carbohydrate-rich diets. Thus, it is possible that NPY may play a role in the enhanced intake of highly palatable diets by AP/mNTS-lesioned rats. In the studies reported here, we found that lesions centered on the AP result in increased levels of NPY-immunoreactivity in the paraventricular nucleus of the hypothalamus. Additionally, steady-state NPY mRNA in the basomedial hypothalamus including the arcuate nucleus was elevated. Enhanced NPY was not found throughout the hypothalamus however, as NPY-immunoreactivity was not elevated in the lateral hypothalamus or the tissue bordering the anteroventral third ventricle. These data suggest the possibility that elevated hypothalamic NPY, particularly in the arcuate and paraventricular nuclei, may contribute to the altered food intake and energy balance observed in rats with lesions centered on the AP.  相似文献   
994.
Rationale and objectives Previous work indicated that tolerance to the anorectic effect of the cannabinoid CB1 receptor antagonist/inverse agonist, rimonabant, developed rather rapidly in rats and mice given access to a standard rodent chow. The present study was designed to investigate whether the reducing effect of rimonabant on intake of a highly palatable food such as a chocolate-flavoured beverage underwent a development of tolerance as rapid as that manifested on intake of a standard rodent chow. Materials and methods To this aim, Wistar rats were concurrently exposed, with unlimited access for 24 h/day, to the chocolate-flavoured beverage, regular food pellets and water. Rimonabant (0, 1.25, 2.5 and 5 mg/kg; i.p.) was administered once a day for 21 consecutive days. Results Rimonabant administration resulted in a dose-dependent suppression of the high, daily intake of the chocolate-flavoured beverage; this effect lasted for the entire 21-day treatment period, without any apparent development of tolerance. Conversely, rimonabant-induced reduction in daily intake of regular food pellets was of a smaller magnitude and was limited to the first 3–4 days of treatment. Conclusions Together, these results indicate that chronically administered rimonabant was more effective and longer-lasting in reducing the intake of a highly palatable food than that of regular food pellets in rats. These results also suggest that rimonabant may be more active on the hedonic rather than nutritive properties of diets.  相似文献   
995.
目的研究电子在人体组织等效材料中形成的“簇点”能量分布情况,以及簇点的产生对生物效应发生的意义。方法针对电子与人体组织等效介质作用的物理机理,利用蒙特卡罗(MC)方法,按一个个相互作用事件(电离、激发、弹性散射、Auger电子发射)方式真实模拟电子在介质中的径迹,通过对这些事件进行统计分析,得到相关结论。结果电子在穿过介质过程中,主要以簇点(大于30%)形式沉积能量,并且80%以上的簇点中的能量沉积在50eV以上;簇点的密集程度与电子能量、簇点直径密切相关,簇点中能量沉积也取决于辐射类型和能量。结论簇点中的能量沉积是诱发组织细胞核内DNA分子各种损伤的最主要因素。  相似文献   
996.
Adult male and female rats were housed in a sedentary condition or given free access to a running wheel for 50 days. Running wheel activity of female rats was higher than that of males throughout the experiment. Food intake, of both male and female rats that could take exercise increased, and the rate of increase of females was greater than that of males. In both males and females there was a positive correlation between food intake and running wheel activity. These findings suggest that the sex difference in the rate of increase in food intake elicited by wheel running is at least partly explained by the sex difference in running wheel activity. Although food intake increased as a function of running wheel activity, the weight gains of both sexes were slower than those of sedentary rats. In both sexes this slower weight gain was mainly due to less accumulation of fat.  相似文献   
997.
BackgroundDespite literature supporting the importance of diet during rehabilitation, minimal research quantifies dietary intake during treatment for alcohol use disorder (AUD).ObjectiveThe aim was to quantify dietary intake and energy balance of patients with AUD during inpatient treatment.DesignThis was a secondary analysis of data from a 4-week observational protocol. Participants self-selected food from a room service menu. Dietary intake was recorded by patients and reviewed by nutrition staff. To quantify nutrient and food group intake, data were coded into Nutrition Data Systems for Research software, versions 2016 and 2017. Daily average intake was calculated for all dietary variables.Participants/settingParticipants (n = 22) were adults seeking treatment for AUD at the National Institutes of Health Clinical Center (Bethesda, MD) between September 2016 and September 2017 and who were enrolled in a study examining the microbiome during AUD rehabilitation. Four participants discontinued protocol participation before study week 4 and were not included in analyses examining change over time.Main outcome measuresWeight change, daily energy, and macronutrient and select micronutrient intakes were the main outcome measures included.Statistical analyses performedMean differences in intake and weight were assessed using nonparametric tests.ResultsSixty-four percent of participants were male; mean ± SD age was 46.3 ± 13.0 years, mean ± SD body mass index (calculated as kg/m2) was 23.9 ± 2.5, and mean intake was 2,665 kcal/d (consisting of 45.9% carbohydrate, 34.9% fat, and 19.1% protein). Eighty percent or more of this sample met the Estimated Average Requirement for 10 of 16 micronutrients assessed. Male participants consumed more energy than estimated needs (P = .003) and gained a mean ± SD of 2.67 ± 1.84 kg (P = .006) when an outlier with weight loss and acute pancreatitis was removed from analysis. Female participants did not gain weight or consume more than estimated energy needs.ConclusionsOverall macronutrient intake was within recommended ranges, but intake of other dietary components and weight gain were variable, supporting the need for individualized nutrition care during AUD treatment.  相似文献   
998.

Objectives

Nutrient intakes of children were surveyed at the time when a nation-wide shift took place in the Republic of Korea from agriculture-based to industrialized society. Taking advantage of the survey locations (see below), possible delay in nutritional improvement in rural areas (as compared with that in an urban area) was also examined.

Methods

In total, 108 4- to 6-year-old children (boys and girls in combination) in 4 kindergartens (KGs; 1 in Seoul and 3 in Jeju Island) participated in the survey in 2003–2004. 24-h food duplicate samples were prepared by the mother of each child. Food items in each duplicate sample were separated and coded with reference to the Dietary Reference Intake for Koreans (the 2005 version). Nutrient intake of the day was estimated from the code and weight followed by summation for daily intake.

Results

The children in the KG in Seoul studied were younger, and therefore were smaller in body size than those in other KGs. Thus, it was considered necessary to evaluate nutrient intake not only on a daily basis, but after adjustment for body weight. The AM daily intake of energy (protein in parenthesis) for the 108 children was 1479 kcal (55 g)/day or 69.8 kcal (2.6 g)/kg body weight/day. Evaluation by individual nutrient suggested that the intake was sufficient for almost all nutrients except for sodium and potassium. Sodium and potassium intake (2285 and 1840 mg/day, respectively) was in excess and insufficient, respectively, with potential risk of inducing hypertension later in life.

Conclusions

Inter-KG difference was not remarkable and therefore urban–rural difference was not apparent. Nutrient intakes as a whole appeared to be sufficient urban and rural areas. Nevertheless, excess Na intake coupled with insufficient K intake was a common problem.  相似文献   
999.
目的了解2011年与2017年南京25岁及以上人群归因于豆类摄入不足的缺血性心脏病(IHD)疾病负担和期望寿命损失情况,为IHD的饮食防控策略提供数据支撑。方法本研究资料来源于2011年和2017年南京市慢性病及其危险因素监测、南京市死因监测和2017全球疾病负担(GBD)资料,采用GBD团队提供的Excel插件程序计算人群归因分值(PAF),估算豆类摄入不足导致的IHD死亡和寿命损失。使用SPSS 20.0软件进行t检验。结果2017年,南京市因豆类摄入不足导致IHD的死亡例数占IHD总死亡例数的13.73%,较2011年(12.44%)增长了10.37%。2017年南京市归因于豆类摄入不足的IHD死亡例数和过早死亡损失寿命年(YLL)分别为645例、8116人年,较2011年(449例、6610人年)分别上升43.65%、22.78%;而标化归因死亡率和标化YLL率分别由2011年的11.05/10万、155.72/10万下降至2017年的8.86/10万、118.66/10万,下降率分别为19.82%、23.80%。2017年,豆类摄入不足导致的IHD死亡使期望寿命损失0.17岁,男性、女性分别损失0.13、0.21岁;与2011年相比,2017年男性、女性及总人群归因于豆类摄入不足的期望寿命损失均上升。结论豆类摄入不足已成为影响南京市居民死亡和期望寿命的饮食危险因素之一,应积极倡导合理膳食,增加居民豆类摄入水平,从而减少心血管疾病负担。  相似文献   
1000.
目的 了解成都市居民膳食中铅、镉暴露的基础数据,评估成都市居民膳食铅、镉暴露风险.方法 对成都市市售食品中铅、镉含量进行监测,参考2002年中国居民营养与健康状况调查中的成都市居民膳食摄入量,应用WHO推荐的食品中化学污染物膳食暴露评估方法,对成都市居民膳食中铅、镉暴露水平进行评估.结果 成都市居民平均每周膳食中铅暴露量为0.006 9 mg/kg BW,占暂定每周可耐受摄入量(PTWI)的27.6%;镉暴露量为0.005 1 mg/kg BW,占暂定每周可耐受摄入量(PTWI)的72.86%.结论成 都市居民膳食中镉暴露水平高于铅暴露水平,正常情况下均低于PTWI,但仍有进一步降低的必要.  相似文献   
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