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71.
Promoter hypermethylation of cyclooxygenase-2 in gastric carcinoma   总被引:5,自引:0,他引:5  
  相似文献   
72.
Although many occupational safety programs are targeted toward large firms, the construction industry is dominated by smaller firms. This study examines the differential effect of firm size on the risk and the reporting of over 3000 serious and minor nonfatal elevation fall injuries in Danish construction industry trades (1993 to 1999). Small firms (<20 employees) accounted for 93% of all firms and 55% of worker-years. There was an inverse relationship between firm size and serious injury rates and a direct relationship between firm size and minor injury rates. An inverse relationship between firm size and injury severity odds ratios (serious versus minor) was found for carpentry, electrical work, general contracting, and the remaining other trades. Health and safety issues, legislation, and enforcement in the construction industry should, to a greater degree, be focused on smaller firms.  相似文献   
73.
To measure the incidence of typhoid fever and other febrile illnesses in Bilbeis District, Egypt, we conducted a household survey to determine patterns of health seeking among persons with fever. Then we established surveillance for 4 months among a representative sample of health providers who saw febrile patients. Health providers collected epidemiologic information and blood (for culture and serologic testing) from eligible patients. After adjusting for the provider sampling scheme, test sensitivity, and seasonality, we estimated that the incidence of typhoid fever was 13/100,000 persons per year, and the incidence of brucellosis was 18/100,000 persons per year in the district. This surveillance tool could have wide applications for surveillance for febrile illness in developing countries.  相似文献   
74.
BACKGROUND: The recent transposition of the Biocides Directive by means of Royal Decree 1054/2002 involves a substantial change in different Environmental Health-related aspects. To assess the impact of these changes, an analysis of the current situation is provided, based on which the consequences of the implementation of this Directive in Spain may be assessed, in addition to setting out the main aspects which must be analyzed with a view to a Biocides Registry being put into place in accordance with the aforementioned Royal Decree. METHODS: The analysis was made based on the data included in the Spanish Ministry of Health and Consumer Affairs related to aerosol insect sprays registered for Household Use. Aerosols were chosen as a result of their being the type most numerous on the market for household use. RESULTS: The formulation of these aerosols includes 25 insecticides, 1 disinfectant and 2 synergizers. A majority of the 298 aerosol insect sprays include some pyretroid in their composition, by itself or combined with some other insecticide, disinfectant and/or synergizing compound. Most of these biocides are a mixture of active substances. CONCLUSIONS: Based on the analysis made, the need of setting out new procedures for assessing the effectiveness of the formulas prepared for the use in question (design of standardized testing protocols, assessment of effectiveness on the different pest species, the effect of the mixture of active ingredients, safety timeframes, ...), in addition to the aspects related to toxicology; ecotoxicology or physicochemical characteristics.  相似文献   
75.
76.
BACKGROUND: Different flow cytometric methods have been developed to derive absolute CD34(+) cells in predicting transplant outcome. Two techniques for preparing cells for quantification of CD34(+) cells were compared. METHODS: Enumeration of CD34(+) cells in 16 samples of bone marrow (BM) and in 29 samples of mobilized peripheral blood stem cells (PBSC) obtained by leukapheresis was assessed simultaneously by single-platform (ProCOUNT kit) and dual-platform (Milan protocol) approaches within the first 3 h of collection. RESULTS: Absolute number of CD34(+) cells obtained in PBSC and BM using single- and dual-platform methods showed high determination coefficients as follows: for PBSC, slope = 1.0515 +/- 0.048, y-intercept = 88.638 +/- 52.45, and r(2) = 0.941, and for BM, slope = 1.0203 +/- 0.093, y-intercept = 122.25 +/- 20.65, and r(2) = 0.878. There were no statistically significant differences in absolute number of CD34(+) cells from PBSC between single-platform (mean 575/microL, range 70-3683/microL) and dual-platform (786/microL, range 51-3804/microL) assays. In contrast, absolute number of CD34(+) cells from BM was significantly lower (p = 0.0002) when enumerated by ProCount kit (135/microL, 14-758/microL) than with dual-platform method (260/microL, 74-889/microL). CONCLUSIONS: Both approaches can be used indistinctly to estimate absolute number of CD34(+) cells in PBSC but not in BM.  相似文献   
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78.
It has long been assumed that Ehrlichia chaffeensis (Anderson, Dawson & Wilson), is not transmitted transovarially in the lone star tick vector Amblyomma americanum (L.). To test this hypothesis, three beagle dogs, Canis familiaris (L.) (Carnivora: Canidae), were subcutaneously infected with E. chaffeensis (Arkansas strain). Uninfected nymphal lone star ticks were placed on the infected dogs and allowed to feed to repletion. These nymphal ticks were allowed to molt, and five of five adult female ticks sampled were confirmed to be infected by polymerase chain reaction (PCR). Forty infected adult ticks, the majority of which were female with several males included to stimulate feeding, were then placed on two uninfected dogs. Fourteen females were removed early and the rest were allowed to feed to repletion. After feeding to repletion, the six remaining females detached and two of these females were tested preoviposition, whereas the remaining four were allowed to lay eggs. All six of these fully engorged females tested negative by PCR. The egg clutches laid by four engorged adult females, and the larvae that hatched from these eggs along with larvae from a previously untested egg clutch, were shown to be uninfected by PCR. This seems to support the long-held assumption of lack of transovarial transmission. Also of interest, we found that these PCR-confirmed infected adult ticks reared in the laboratory did not transmit E. chaffeensis to uninfected dogs.  相似文献   
79.
Escherichia coli O157:H7 causes 73,000 illnesses in the United States annually. We reviewed E. coli O157 outbreaks reported to Centers for Disease Control and Prevention (CDC) to better understand the epidemiology of E. coli O157. E. coli O157 outbreaks (>or=2 cases of E. coli O157 infection with a common epidemiologic exposure) reported to CDC from 1982 to 2002 were reviewed. In that period, 49 states reported 350 outbreaks, representing 8,598 cases, 1,493 (17%) hospitalizations, 354 (4%) hemolytic uremic syndrome cases, and 40 (0.5%) deaths. Transmission route for 183 (52%) was foodborne, 74 (21%) unknown, 50 (14%) person-to-person, 31 (9%) waterborne, 11 (3%) animal contact, and 1 (0.3%) laboratory-related. The food vehicle for 75 (41%) foodborne outbreaks was ground beef, and for 38 (21%) outbreaks, produce.  相似文献   
80.
BACKGROUND: The increased prevalence of overweight in Canadian children has stimulated interest in their lifestyle behaviours. The purpose of this research was to investigate dietary intake and food behaviours of Ontario students in grades six, seven, and eight. METHODS: Males and females from grades six to eight were recruited from a stratified random selection of schools from Ontario. Data were collected using the web-based "Food Behaviour Questionnaire", which included a 24-hour diet recall and food frequency questionnaire. Nutrients were analyzed using ESHA Food Processor and the 2001 Canadian Nutrient File database. Body Mass Index (BMI) was calculated based on self-reported weight and height, and classified according to the Centers for Disease Control BMI for age percentiles. RESULTS: The sample included males (n = 315) and females (n = 346) in grades 6, 7, and 8 from 15 schools in Ontario. According to Canada's Food Guide to Healthy Eating (CFGHE), median intakes were below recommendations for all participants, with the exception of meat and alternatives. Participants consumed a median of 54%, 15%, 31%, 11%, and 8% of total energy from carbohydrates, protein, total fat, saturated fat, and added sugars, respectively. Participants consumed 25% of total energy from foods from the "other" food group (CFGHE). Males had higher intakes of energy, carbohydrates, fat, saturated fat, monounsaturated fat, protein, thiamine, niacin, iron, and zinc than females (all p < 0.05), and consumed more grain products servings (p < 0.05). CONCLUSION: The high consumption of "other" foods, at the expense of nutrient-dense food groups, may ultimately be contributing to the increased weights in childhood and adolescence.  相似文献   
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