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991.

OBJECTIVE

To evaluate the larvicidal activity of Azadirachta indica, Melaleuca alternifolia, carapa guianensis essential oils and fermented extract of Carica papaya against Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae).

METHODS

The larvicide test was performed in triplicate with 300 larvae for each experimental group using the third larval stage, which were exposed for 24h. The groups were: positive control with industrial larvicide (BTI) in concentrations of 0.37 ppm (PC1) and 0.06 ppm (PC2); treated with compounds of essential oils and fermented extract, 50.0% concentration (G1); treated with compounds of essential oils and fermented extract, 25.0% concentration (G2); treated with compounds of essential oils and fermented extract, 12.5% concentration (G3); and negative control group using water (NC1) and using dimethyl (NC2). The larvae were monitored every 60 min using direct visualization.

RESULTS

No mortality occurred in experimental groups NC1 and NC2 in the 24h exposure period, whereas there was 100% mortality in the PC1 and PC2 groups compared to NC1 and NC2. Mortality rates of 65.0%, 50.0% and 78.0% were observed in the groups G1, G2 and G3 respectively, compared with NC1 and NC2.

CONCLUSIONS

The association between three essential oils from Azadirachta indica, Melaleuca alternifolia, Carapa guianensis and fermented extract of Carica papaya was efficient at all concentrations. Therefore, it can be used in Aedes aegypti Liverpool third larvae stage control programs.  相似文献   
992.
Background: Nitrogen dioxide (NO2), a ubiquitous atmospheric pollutant, may enhance the asthmatic response to allergens through eosinophilic activation in the airways. However, the effect of NO2 on inflammation without allergen exposure is poorly studied.Objectives: We investigated whether repeated peaks of NO2, at various realistic concentrations, induce changes in airway inflammation in asthmatics.Methods: Nineteen nonsmokers with asthma were exposed at rest in a double-blind, crossover study, in randomized order, to 200 ppb NO2, 600 ppb NO2, or clean air once for 30 min on day 1 and twice for 30 min on day 2. The three series of exposures were separated by 2 weeks. The inflammatory response in sputum was measured 6 hr (day 1), 32 hr (day 2), and 48 hr (day 3) after the first exposure, and compared with baseline values measured twice 10–30 days before the first exposure.Results: Compared with baseline measurements, the percentage of eosinophils in sputum increased by 57% after exposure to 600 ppb NO2 (p = 0.003) but did not change significantly after exposure to 200 ppb. The slope of the association between the percentage of eosinophils and NO2 exposure level was significant (p = 0.04). Eosinophil cationic protein in sputum was highly correlated with eosinophil count and increased significantly after exposure to 600 ppb NO2 (p = 0.001). Lung function, which was assessed daily, was not affected by NO2 exposure.Conclusions: We observed that repeated peak exposures of NO2 performed without allergen exposure were associated with airway eosinophilic inflammation in asthmatics in a dose-related manner.Citation: Ezratty V, Guillossou G, Neukirch C, Dehoux M, Koscielny S, Bonay M, Cabanes PA, Samet JM, Mure P, Ropert L, Tokarek S, Lambrozo J, Aubier M. 2014. Repeated nitrogen dioxide exposures and eosinophilic airway inflammation in asthmatics: a randomized crossover study. Environ Health Perspect 122:850–855; http://dx.doi.org/10.1289/ehp.1307240  相似文献   
993.

Objective

to analyze the sociodemographic characteristics, epidemic trend and spatial distribution of the risk of AIDS in adults 50 years of age and over.

Method

population-based, ecological study, that used secondary data from the Notifiable Disease Information System (Sinan/AIDS) of Paraíba state from the period January 2000 to December 2010.

Results

during the study period, 307 cases of AIDS were reported among people 50 years of age or over. There was a predominance of males (205/66, 8%), mixed race, and low education levels. The municipalities with populations above 100 thousand inhabitants reported 58.5% of the cases. There was a progressive increase in cases among women; an increasing trend in the incidence (positive linear correlation); and an advance in the geographical spread of the disease, with expansion to the coastal region and to the interior of the state, reaching municipalities with populations below 30 thousand inhabitants. In some locations the risk of disease was 100 times greater than the relative risk for the state.

Conclusion

aging, with the feminization and interiorization of the epidemic in adults 50 years of age and over, confirms the need for the induction of affirmative policies targeted toward this age group.  相似文献   
994.
Objectives. We investigated relations between changes in neighborhood ethnic composition and changes in body mass index (BMI) and waist circumference among Chinese and Hispanic immigrants in the United States.Methods. We used Multi-Ethnic Study of Atherosclerosis data over a median 9-year follow-up (2000–2002 to 2010–2012) among Chinese (n = 642) and Hispanic (n = 784) immigrants aged 45 to 84 years at baseline. We incorporated information about residential moves and used econometric fixed-effects models to control for confounding by time-invariant characteristics. We characterized neighborhood racial/ethnic composition with census tract–level percentage Asian for Chinese participants and percentage Hispanic for Hispanic participants (neighborhood coethnic concentration).Results. In covariate-adjusted longitudinal fixed-effects models, results suggested associations between decreasing neighborhood coethnic concentration and increasing weight, although results were imprecise: within-person BMI increases associated with an interquartile range decrease in coethnic concentration were 0.15 kilograms per meters squared (95% confidence interval [CI] = 0.00, 0.30) among Chinese and 0.17 kilograms per meters squared (95% CI = –0.17, 0.51) among Hispanic participants. Results did not differ between those who did and did not move during follow-up.Conclusions. Residential neighborhoods may help shape chronic disease risk among immigrants.More than 40 million immigrants reside in the United States, 81% of whom emigrated from Latin America or Asia.1 Not only is the US foreign-born population increasing, but also is the proportion of immigrants who have resided in the United States for a long period of time. An estimated 39% of immigrants had resided in the United States for 20 years or more as of 2010, and this proportion is projected to surpass 50% by 2030.2 This demographic shift has important ramifications for population health and the health service burden because, among immigrants, both cardiovascular disease (CVD) risk and weight, a key CVD risk factor, tend to increase with longer length of stay in the United States, above and beyond the influence of age.3–7Although explanations for immigrant health patterns often focus on how individual-level health behaviors change across time to align with those of the receiving US culture,5 broader factors may also be important. For example, the neighborhoods in which immigrants reside may contribute to weight changes associated with tenure in the United States. Recent immigrants tend to initially settle in immigrant enclaves, neighborhoods with large numbers of other immigrants of the same country of origin or ethnicity (high coethnic concentration). However, over time, many immigrants move out of immigrant enclaves to neighborhoods with lower proportions of other coethnics or immigrants.8 Classical sociological spatial assimilation theory posits that this process of residential spatial assimilation serves as one important dimension of assimilation into the dominant US culture.8–10 Although the theory does not explicitly state how health would be affected, it implies changes in exposures to neighborhood-level social and physical characteristics that could influence health.Weight-related physical and social resources in neighborhoods with large immigrant populations may differ from those with fewer immigrants.9,11–13 For example, businesses in immigrant enclaves often provide services or products specific to their ethnic market, including food stores.9,12 Empirical findings on whether the food environment in immigrant enclaves is healthier than in other neighborhoods are inconsistent. Higher neighborhood proportions of Hispanic and Asian residents have been associated with higher numbers of convenience stores and fast-food restaurants—sources of unhealthy foods—but also with higher numbers of nonchain supermarkets and grocery stores, which may contribute to a healthier and more culturally appropriate food environment.14–16 Chinese and Hispanic participants living in immigrant enclaves have reported better availability of healthy food than participants living in other neighborhoods.13 Other aspects of the built environment that are relevant to weight, such as how conducive to walking it is, may also vary by neighborhood ethnic composition.13 Aside from physical resources, the presence of other immigrants in a neighborhood may provide psychosocial benefits by buffering residents against discrimination or by providing access to larger social networks,11,17 but the empirical evidence is again inconsistent.13 These neighborhood differences may in turn affect behavioral and psychosocial determinants of weight.18–23 For example, higher immigrant and ethnic concentration has been associated with differences in diet and physical activity,13,24–27 as well as with better mental health and less perceived discrimination,17,28–35 all of which could have an impact on weight.Few studies have examined associations between neighborhood ethnic composition and weight among immigrants.36–41 Results have varied depending on the immigrant group examined or the composition measure used (e.g., percentage foreign-born, percentage Hispanic).36–39 Moreover, the majority of previous evidence is cross-sectional and cannot investigate patterns of residential mobility, including spatial assimilation, that may affect weight over time.42 Longitudinal studies are therefore crucial for understanding how neighborhood context may affect weight over time in immigrants.3 Despite substantial theoretical and empirical sociological research dedicated to characterizing residential patterns among immigrants, there is little research in either sociology or public health that explicitly examines the implications of these patterns for health.We used longitudinal econometric fixed-effects models to investigate whether changes in neighborhood ethnic composition were related to changes in body mass index (BMI; defined as weight in kilograms divided by the square of height in meters) and waist circumference (WC) over a median follow-up of 9 years among a cohort of Chinese and Hispanic immigrants in the United States. Because fixed-effects models rely only on intraindividual variability, and therefore tightly control for all time-invariant individual-level characteristics, this approach can reduce the likelihood that observed results are confounded.43 We hypothesized that decreases in neighborhood coethnic concentration would be related to increases in BMI and WC in our sample. We also hypothesized that immigrants who spatially assimilated during follow-up (i.e., who moved to a neighborhood with lower coethnic concentration, as opposed to staying in the same residence with their neighborhood changing around them) would experience greater increases in BMI and WC. Our second hypothesis was driven by the idea that, consistent with classical spatial assimilation theory, spatial assimilation may denote a greater likelihood of adopting less healthy behaviors associated with the dominant US culture.  相似文献   
995.
Background: Development of the epidermal permeability barrier (EPB) is essential for neonatal life. Defects in this barrier are found in many skin diseases such as atopic dermatitis.Objective: We investigated the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the development and function of the EPB.Methods: Timed-pregnant C57BL/6J mice were gavaged with corn oil or TCDD (10 μg/kg body weight) on gestation day 12. Embryos were harvested on embryonic day (E) 15, E16, E17, and postnatal day (PND) 1.Results: A skin permeability assay showed that TCDD accelerated the development of the EPB, beginning at E15. This was accompanied by a significant decrease in transepidermal water loss (TEWL), enhanced stratification, and formation of the stratum corneum (SC). The levels of several ceramides were significantly increased at E15 and E16. PND1 histology revealed TCDD-induced acanthosis and epidermal hyperkeratosis. This was accompanied by disrupted epidermal tight junction (TJ) function, with increased dye leakage at the terminal claudin-1–staining TJs of the stratum granulosum. Because the animals did not have enhanced rates of TEWL, a commonly observed phenotype in animals with TJ defects, we performed tape-stripping. Removal of most of the SC resulted in a significant increase in TEWL in TCDD-exposed PND1 pups compared with their control group.Conclusions: These findings demonstrate that in utero exposure to TCDD accelerates the formation of an abnormal EPB with leaky TJs, warranting further study of environmental exposures, epithelial TJ integrity, and atopic disease.Citation: Muenyi CS, Leon Carrion S, Jones LA, Kennedy LH, Slominski AT, Sutter CH, Sutter TR. 2014. Effects of in utero exposure of C57BL/6J mice to 2,3,7,8-tetrachlorodibenzo-p-dioxin on epidermal permeability barrier development and function. Environ Health Perspect 122:1052–1058; http://dx.doi.org/10.1289/ehp.1308045  相似文献   
996.
Oral vaccination against classical swine fever (CSF) is a potent tool to control disease outbreaks in wild boar. So far, vaccination campaigns have been carried out using live attenuated vaccines that do not allow serological differentiation of infected from vaccinated animals (DIVA). Although this drawback is acceptable for wild boar, the use of marker vaccines would facilitate studies on disease and vaccination dynamics. Recently, the CSF marker vaccine candidate CP7_E2alf was assessed for oral immunization under laboratory conditions. Promising results prompted efforts to study the vaccine candidate under field conditions and in bait formulation. In this context, two oral vaccination campaigns were carried out with CP7_E2alf bait vaccines in two areas called ‘faunistic-hunting farms’ in the region of Umbria, Italy. One campaign was conducted using single vaccination, the second with the routinely employed double vaccination strategy. Both campaigns were carried out before concerted hunting actions were performed. Bait uptake, vaccine virus detection and antibody responses were assessed along with inspections upon gutting. As a comparator, seven wild boar were hand-fed with baits under laboratory conditions. In the field, bait uptake ranged from 63.7% to 98.7%, whereas antibody prevalence reached only 33.3–35.1%. The marker serology showed a strong influence of sample quality on the test outcome with a total of 85% of samples being classified correctly. Vaccine virus was not detectable. Under hand feeding conditions, six out of seven wild boar took up at least one bait, and five of them showed detectable antibody levels seven weeks after vaccination. These results were supplemented by stability tests. Appropriate stability of vaccine virus was shown both under field and laboratory conditions. In total, most results were in line with our expectations. However, optimization of the DIVA assay has to be attempted in the future.  相似文献   
997.

Objective

We aimed to explore the impacts of new vaccine introductions on immunization programmes and health systems in low- and middle-income countries.

Methods

We conducted case studies of seven vaccine introductions in six countries (Cameroon, PCV; Ethiopia, PCV; Guatemala, rotavirus; Kenya, PCV; Mali, Meningitis A; Mali, PCV; Rwanda, HPV). Interviews were conducted with 261 national, regional and district key informants and questionnaires were completed with staff from 196 health facilities. Routine data from districts and health facilities were gathered on vaccination and antenatal service use. Data collection and analysis were structured around the World Health Organisation health system building blocks.

Findings

The new vaccines were viewed positively and seemed to integrate well into existing health systems. The introductions were found to have had no impact on many elements within the building blocks framework. Despite many key informants and facility respondents perceiving that the new vaccine introductions had increased coverage of other vaccines, the routine data showed no change. Positive effects perceived included enhanced credibility of the immunisation programme and strengthened health workers’ skills through training. Negative effects reported included an increase in workload and stock outs of the new vaccine, which created a perception in the community that all vaccines were out of stock in a facility. Most effects were found within the vaccination programmes; very few were reported on the broader health systems. Effects were primarily reported to be temporary, around the time of introduction only.

Conclusion

Although the new vaccine introductions were viewed as intrinsically positive, on the whole there was no evidence that they had any major impact, positive or negative, on the broader health systems.  相似文献   
998.
Forms of collaborative knowledge production, such as community-academic partnerships (CAP), have been increasingly used in health care. However, instructions on how to deliver such processes are lacking. We aim to identify practice ingredients for one element within a CAP, a 6-month co-design process, during which 26 community- and 13 research-partners collaboratively designed an intervention programme for children whose parent have a mental illness. Using 22 published facilitating and hindering factors for CAP as the analytical framework, eight community-partners reflected on the activities which took place during the co-design process. From a qualitative content analysis of the data, we distilled essential practices for each CAP factor. Ten community- and eight research-partners revised the results and co-authored this article. We identified 36 practices across the 22 CAP facilitating or hindering factors. Most practices address more than one factor. Many practices relate to workshop design, facilitation methods, and relationship building. Most practices were identified for facilitating ‘trust among partners’, ‘shared visions, goals and/or missions’, ‘effective/frequent communication’, and ‘well-structured meetings’. Fewer practices were observed for ‘effective conflict resolution’, ‘positive community impact’ and for avoiding ‘excessive funding pressure/control struggles’ and ‘high burden of activities’. Co-designing a programme for mental healthcare is a challenging process that requires skills in process management and communication. We provide practice steps for delivering co-design activities. However, practitioners may have to adapt them to different cultural contexts. Further research is needed to analyse whether co-writing with community-partners results in a better research output and benefits for participants.  相似文献   
999.

Background

It has been proposed that the expression of pain-related suffering may lead to an enhanced focus on oneself and reduced attention toward the external world. This study aimed at investigating whether experimentally induced painrelated suffering may lead persons to withdraw into themselves, causing a reduced focus on external stimuli as reflected by impaired performance in a facial recognition task and heightened perception of internal stimuli measured by interoceptive awareness.

Methods

Thirty-two participants had to recognize different emotional facial expressions (neutral, sad, angry, happy), or neutral geometrical figures under conditions of no pain, low, and high prolonged pain intensities. Interoceptive accuracy was measured using a heartbeat-detection task prior to and following the pain protocol.

Results

Males but not females were slower to recognize facial expressions under the condition of high painful stimulation compared to the condition of no pain. In both, male and female participants, the difficulty in recognizing another person's emotions from a facial expression was directly related to the level of suffering and unpleasantness experienced during pain. Interoceptive accuracy was higher after the pain experiment. However, neither the initial interoceptive accuracy nor the change were significantly related to the pain ratings.

Conclusions

Our results suggest that long-lasting and intense painful stimuli, which induce suffering, lead to attentional shifts leading to withdrawal from others. These findings contribute to a better understanding of the social dynamics of pain and pain-related suffering.  相似文献   
1000.
Residual giant‐cystic craniopharyngiomas are amenable to intracavitary bleomycin treatment. Radiologic identification of potential cyst leaks is of paramount for treatment decisions. This report describes our experience in the use of intracystic Gadolinium (Gd)‐enhanced MR imaging to determine potential communications between the tumoral cysts and other intra‐axial spaces in 4 pediatric patients with residual giant‐cystic craniopharyngiomas in whom intracavitary bleomycin treatment was planned after the injection of .1‐.2 mL of gadopentetate dimeglumine (Gd‐DTPA). In three cases no leaks were found. In one case, whose previous water‐soluble iodinated contrast‐enhanced CT cystography was negative for leaks, intracystic Gd‐enhanced MR showed intraventricular Gd enhancement. We conclude that MR imaging after intracystic administration of Gd‐based contrast paramagnetic agents is useful in the detection of potential leaks in cases of giant residual craniopharyngiomas.  相似文献   
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