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991.
The aim of this study was to determine the no-observable-adverse-effect concentration (NOAEC) for trichlorfon, an antiparasitic agent used in aquaculture, in Piractus mesopotamicus (pacu) using acetylcholinesterase (AChE) activity as an end point. Fish were exposed 24 h/d for 15 d to different concentrations of trichlorfon in tanks of water for which a curve of dissipation was previously determined. Analysis of trichlorfon in water and fish plasma using gas chromatography with electron capture detection (GC-ECD) enabled measurement of limit of detection (LOD) and limit of quantification (LOQ), respectively, to be 3 and 10 ppb. Thirty-six hours after trichlorfon dilution in water, the concentration was below the LOD, and data showed that plasma concentrations did not exceed the LOQ. Apart from the 6.25 μg/L, all concentrations of trichlorfon significantly inhibited plasma and brain AChE activity compared to controls. The AChE activity levels returned to control values in 7 d. These data may be useful to determine the concentration of trichlorfon that destroys parasites without producing adverse effects in fish.  相似文献   
992.

Purpose

Infant medulloblastoma (MB) is a malignant neuroepithelial embryonal tumor of the cerebellum, believed to derive from precursor granule cells with stem or progenitor cells appearance, and caused by a change in expression profile of genes related to the development. This work aims to study the expression profile of these genes in MB tumors, correlating with clinicopathological characteristics.

Methods

We quantified, by qPCR in 40 MB tumor samples, the expression of genes in HH (PTCH1, PTCH2, and GLI1), WNT (APC, CTNNB1, WIF1, and DKK2), and NOTCH pathways (NOTCH2 and HES1), which have a crucial role in development, and genes as MYCC, MYCN, and TERT, correlating this findings to patient’s clinicopathological characteristics.

Results

Considering the universal RNA as our control sample, and considering the median of gene expression in the control samples as our cutoff, we observed that HES1 gene showed decreased expression compared to control (p?=?0.0059), but patients with HES1 overexpression were directly related to a shorter survival (p?=?0.0165). Individuals with higher GLI1 gene expression had significant shorter survival (p?=?0.0469), and high expression was prevalent in patients up to 5 years old (p?=?0.0479). Patients showing high PTCH2 expression were related to worse survival (p?=?0.0426), and it was correlated with GLI1 high expression (p?=?0.0094). We also observed a concomitant overexpression of WIF1 and DKK2 genes in a subgroup of MB samples (n?=?11, p?=?0.0118).

Conclusions

Our results suggest the presence of activated developmental signaling pathways in MB, which are important for cell proliferation and maintenance, and that may be targeted for novel therapeutic options.  相似文献   
993.

Objective

The literature suggests that a fetus will adapt to surrounding adversities by optimizing its use of energy to improve survival, ultimately leading to the programming of the individual's energy intake and expenditure. While recent reviews focused on the fetal programming of energy intake and food preferences, there is also some evidence that fetal adversity is associated with diminished physical activity levels. Therefore, we aimed to review (a) the evidence for an association between being born with intrauterine growth restriction and sedentarism over the life-course and (b) the potential benefits of physical activity over cardiometabolic risk factors for this population.

Sources

PubMed, Scielo, Scopus and Embase.

Summary of findings

Most clinical studies that used objective measures found no association between intrauterine growth restriction and physical activity levels, while most studies that used self-reported questionnaires revealed such relationships, particularly leisure time physical activity. Experimental studies support the existence of fetal programming of physical activity, and show that exposure to exercise during IUGR individuals’ life improves metabolic outcomes but less effect was seen on muscle architecture or function.

Conclusions

Alterations in muscle strength and metabolism, as well as altered aerobic performance, may predispose IUGR individuals to be spontaneously less physically active, suggesting that this population may be an important target for preventive interventions. Although very heterogeneous, the different studies allow us to infer that physical activity may have beneficial effects especially for individuals that are more vulnerable to metabolic modifications such as those with IUGR.  相似文献   
994.
Presbycusis is a common disorder in the elderly, which causes hearing loss and may contribute to the development of some psychiatric disorders, leading to isolation due to communication difficulties in the social environment.ObjectiveTo identify through the WHOQOL (World Health Organization Quality of Life Questionnaire), the quality of life of hearing impaired individuals before and after hearing aid fittings.MethodWe had 30 individuals with hearing loss, all over 60 years of age - patients from a Speech Therapy Clinic. The patients answered the WHOQOL questions without the use of hearing aids; and after the effective use of a sound amplification device for a period of three months they answered it again. The WHOQOL - Bref consists of 26 questions, two general quality-of-life questions and 24 associated with four aspects: physical, psychological, environmental and social relations.ResultsThere was a significant improvement in quality of life in general, as far as leisure activities were concerned, there were no major changes regarding the frequency of negative feelings; even after the hearing aid fitting, the patients continue to have such feelings.ConclusionThe use of hearing aids favored the overall quality of life of the individuals evaluated.  相似文献   
995.
This paper reports the results of environmental surveillance of yeasts in specific areas of two tertiary local hospitals. From March 2007 to February 2008, samples from the air of two public hospitals were collected on a monthly basis. The samples were collected through passive sedimentation method (day and night exposure) of Petri dishes. A total of 240 air samples from 10 hospital environments were analyzed. These environments presented similar contamination levels, from which 80 fungi isolates were isolated: Candida parapsilosis (n = 34), Rhodotorula spp. (19), Trichosporon asahii (11), C. tropicalis (8), C. albicans (4), C. glabrata (1), C. guilliermondii (1), C. krusei (1) and Saccharomyces spp. (1). Regarding the presence of yeasts and climatic conditions, there were 40 strains (50%) in semi-critical areas (natural ventilation) and critical areas (air conditioned). Considering the presence of microorganisms with pathogenic potential, environmental monitoring is necessary to prevent possible hospital infections.  相似文献   
996.
Purpose: To assess the association between hypertension in pregnancy and women’s quality of life (QoL) and the variation in the quality of life over gestational trimesters. Method: A questionnaire was applied to 194 hypertensive pregnant women and 195 pregnant women without complications. The questionnaire was composed of two parts: socioeconomic profile and specifically QoL, using the instrument Ferrans & Powers Quality of Life Index. All women included underwent a physical examination. Results: Blood pressure was found to be approximately 20 mmHg higher in hypertensive pregnant women compared to pregnant women without complications. All QoL domains of hypertensive pregnant women had lower scores than those of pregnant women without complications, with health/functioning rated the lowest, averaging 17.63. The least affected domain was family, having the best average score (26.0). The QoL had no significant variations in relation to gestational trimesters. Conclusions: Pregnancy causes intense changes, both physical and psychological, in women’s lives and hypertension was found to be a factor of high interference in pregnant woman’s QoL, causing lower scores in all QoL domains of hypertensive pregnant women, compared with pregnant woman without complications.  相似文献   
997.

Background  

Economic development is often evoked as a driving force that has the capacity to improve the social and health conditions of remote areas. However, development projects produce uneven impacts on local communities, according to their different positions within society. This study examines the spatial distribution of three major health threats in the Brazilian Amazon region that may undergo changes through highway construction. Homicide mortality, AIDS incidence and malaria prevalence rates were calculated for 70 municipalities located within the areas of influence of the Cuiabá-Santarém highway (BR-163), i.e. in the western part of the state of Pará state and the northern part of Mato Grosso.  相似文献   
998.
Objectives Microsatellite instability (MSI) induction by alkylating agent‐based chemotherapy (ACHT) may underlie both tumor resistance to chemotherapy and secondary leukaemias in cancer patients. We investigated if ACHT could induce MSI in tumor‐derived plasma‐circulating DNA (pfDNA) and in normal peripheral blood mononuclear (PBMN) cells. We also evaluated if amifostine could interfere with this process in an in‐vitro model. Methods MSI was determined in pfDNA, PBMN cells and urine cell‐free DNA (ufDNA) of 33 breast cancer patients before and after ACHT. MCF‐7 cells and PBMN from normal donors were exposed in vitro to melphalan, with or without amifostine. Results We observed at least one MSI event in PBMN cells, pfDNA or ufDNA of 87, 80 and 80% of patients, respectively. In vitro, melphalan induced MSI in both MCF‐7 and normal PBMN cells. In PBMN cells, ACHT‐induced MSI occurred together with a significant decrease in the expression of the DNA mismatch repair gene hMSH2. Amifostine decreased hMSH2 expression and also prevented MSI induction only in normal PBMN cells. Conclusions ACHT induced MSI in PBMN cells and in tumour‐derived pfDNA. Because of its protective effect against ACHT induction of MSI in normal PBMN cells in vitro, amifostine may be a potential agent for preventing secondary leukaemias in patients exposed to ACHT.  相似文献   
999.
Currently in Portugal, universal screening of pregnant women for Cytomegalovirus (CMV) infection is not performed. However, it is recommended to screen all women attending preconception care. We aimed to assess women’s attendance to preconception care and if their serologic status regarding CMV was known and/or investigated in that consultation. In this cross-sectional study, we interviewed 240 women admitted to the obstetrical ward of a hospital in the Metropolitan Area of Porto (Portugal) about their adherence to preconception care and collected data regarding their CMV serologic status and its investigation. We found that 71.3% of the women who attended preconception care were not screened for CMV infection. Among primigravida, the screening rate was only of 30.4% (upper limit of CI 95%: 44.8%). There were no statistically significant differences between the private and public sectors of healthcare. We observed attendance to preconception care is high (73.1%). For the population subgroup of the metropolitan area of Porto, attendance to preconception care is at least 66%, with a 95% confidence level. Portuguese guidelines stating a woman’s serologic status regarding CMV should be investigated in preconception care are not properly implemented. This suggests guidelines should assure the screening of previously non-screened women during pregnancy.  相似文献   
1000.
Two basic premises of Brazil's Community Health Agents Program (PACS) are to value the family and community to which the program belongs and to encourage their participation in health promotion and disease prevention. This study focused on the work developed by PACS in Bauru, S?o Paulo State, as perceived by the community health agents and the families served by them. As the study's point of departure, 22 community health agents and 22 representatives of families were interviewed, randomly selected according to residential micro-areas. Two focus groups were formed according to the PACS to which the community agents and families belonged. Qualitative analysis of the answers demonstrated agreement between the perceptions by community health agents and the community in the two focus groups. However, the two focus groups differed from each other. Distinct realities were observed in the two communities, thereby orienting new program actions and handling of local difficulties.  相似文献   
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