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991.
A discrepancy exists between the interest in modern methods of natural family planning (NFP) and their actual use in developed countries. To explore reasons for this discrepancy, we analyzed data from a questionnaire administered to postpartum women in Berlin (n = 223) and Cracow (n = 233). Knowledge of NFP, past use of NFP and expected effects of abstinence on the partnership were independently associated with interest in using NFP, but not the choice to do so among those interested. Desire for future pregnancies, importance of religious belief and location in Cracow were independently associated with the choice to use NFP among those interested. Perceived accuracy of observation to identify the fertile time and acceptance of own body were independently associated with both interest in and choice to use NFP. Frequency of intercourse had no effect on interest. These results suggest that increased access and cultural support would likely lead to a higher prevalence of NFP use in developed countries. 相似文献
992.
Graciela León Ana M Quirós José L López Meilyn Hung Ana M Díaz Juvic Goncalves Osiris Da Costa Teodoro Hernández Merlin Chirinos Rafael Gómez 《Pan American journal of public health》2003,13(2-3):117-123
OBJECTIVE: To conduct research at the Municipal Blood Bank of Caracas (MBBC) and find out the proportion of blood units discarded for being seropositive for human T-lymphotropic virus (HTLV) types I and II, the prevalence of that infection among their donors, and the probable risk factors for that infection among those HTLV-positive donors. METHODS: ELISA serological testing was done with 23 413 donors seen at the MBBC between July 2000 and April 2001. Samples that were repeat reactive (RR) with the ELISA underwent supplementary Western blot (WB) testing. Donors who had a positive or indeterminate WB result were scheduled for counseling in order to carry out confirmatory testing using nucleic acid amplification (NAA), to collect data on their risk background, and to advise them concerning their HTLV status. RESULTS: Of the 23 413 MBBC donors, 48 of them (0.2%) had a donation that was RR. Of those 48, 25 of them (52.1%) were positive on the WB (23 for HTLV-I and 2 for HTLV-II), 2 of them (4.1%) were indeterminate on the WB, 14 of them (29.2%) were negative, and 7 (14.6%) could not be evaluated. Of the 27 donors scheduled for counseling, 16 of them actually attended (14 WB-positive for HTLV-I, 1 WB-positive for HTLV-II, and 1 indeterminate). All 16 of them were positive with the confirmatory NAA testing. When these 16 seropositive donors were compared with a control group of seronegative donors, no significant differences were found with regard to age, sex, type of donation, number of previous donations, history of transfusions, and sexual behavior. However, significant differences were found in two areas: the seropositive donors were more likely to have used non-intravenous drugs (P < 0.05), and the seropositive donors were much more likely to have had an extended breast-feeding period (more than 2 years) as a child (P < 0.001). To assess the probability of mother-to-child transmission, six of the mothers of seropositive donors who had had an extended breast-feeding period were tested, and all six of those mothers were also found to be seropositive. With the 16 seropositive donors who were counseled, the spouse or partner of 13 of them was also tested; only 1 of those 13 was positive, but the oldest son of that couple was also HTLV-positive. CONCLUSIONS: Of the donated blood, 0.2% of the units were discarded for being positive for HTLV-I or HTLV-II, and the prevalence found among the donors was 0.11%. Sexual transmission between an HTLV-positive donor and a partner or spouse was less frequent than was mother-to-child transmission. At present in Venezuela, blood banks are not required to screen donations for HTLV. Given our results at the MBBC, we believe serious consideration should be given to implementing serological screening for HTLV I/II among blood donors throughout Venezuela. 相似文献
993.
O'Mathúna B Farré M Rostami-Hodjegan A Yang J Cuyàs E Torrens M Pardo R Abanades S Maluf S Tucker GT de la Torre R 《Journal of clinical psychopharmacology》2008,28(5):523-529
3,4-Methylenedioxymethamphetamine (MDMA, ecstasy) is a widely abused substituted amphetamine. MDMA is predominantly O-demethylenated in humans by cytochrome P450 isoforms 2D6 and 1A2 (CYP2D6 and CYP CYP1A2, respectively). MDMA is also a mechanism-based inhibitor of CYP2D6. A controlled clinical trial was conducted in 15 healthy male subjects whereby a probe drug, dextromethorphan (DEX), was administered after an oral dose of 1.5 mg/kg MDMA. The pharmacokinetics of DEX and its metabolites were used to evaluate changes in CYP2D6 activity. The urinary metabolic ratio of DEX and dextrorphan was used to calculate a recovery half-life of CYP2D6. After MDMA, DEX Cmax and area under the curve increased approximately 10-fold with corresponding decreases in dextrorphan pharmacokinetic parameters. The metabolic ratio increased almost 100-fold from 0.0061 +/- 0.0056 to 0.4322 +/- 0.2848 after MDMA administration, with 67% of the subjects having a value greater than the antimode of 0.3 for assigning the poor metabolizer phenotype. CYP2D6 activity recovered after 10 days with a recovery half-life of 46.6 hours. In addition to the possible long-term serotonergic effects of MDMA, users must be warned of the consequences of such an inhibition. 相似文献
994.
Gómez-Bombarelli R González-Pérez M Pérez-Prior MT Manso JA Calle E Casado J 《Chemical research in toxicology》2008,21(10):1964-1969
The alkylating potential of diketene (4-methylene-2-oxetanone), the basic unit of many derivatives of pesticides, chemicals, pharmaceuticals, and dyestuffs, was investigated kinetically. The nucleophile 4-( p-nitrobenzyl)pyridine (NBP), a trap for alkylating agents with nucleophilic characteristics similar to DNA bases, was used as an alkylation substrate. The alkylation reactions were performed in water/dioxane solvent mixtures. To gain insight into the effect of the hydrolysis of diketene on its alkylating efficiency, alkylation and competing hydrolysis were studied in parallel. Conclusions were drawn as follows: (i) Although diketene, unlike other four-membered ring lactones, is inactive as a carcinogen in experimental animals, it shows an alkylating potential of about 2 orders of magnitude higher than beta-propiolactone or beta-butyrolactone, which are classified as possibly carcinogenic to humans by the IARC. (ii) The reactivity of diketene as an alkylating agent is enthalpy-controlled. (iii) The fact that the hydrolysis reaction of diketene is slightly faster than those of other four-membered ring lactones shows that diketene is more efficient than beta-propiolactone or beta-butyrolactone as an alkylating agent, since the hydrolysis of this species poses less competition to the alkylation reaction. (iv) Diketene undergoes acyl fission in the alkylation reaction, which results in an amide bond in the NBP-diketene adduct. The lability of the amide bond as opposed to the amine bonds formed by beta-propiolactone and beta-butyrolactone could be one of the differential factors responsible for the lack of carcinogenicity of diketene. (v) Ab initio calculations of the energy barriers help to understand the unusual reactivity of diketene. 相似文献
995.
Sarti FM Claro RM Bandoni DH 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》2011,27(4):639-647
Food choice in diet composition is a determinant of individual health status. Currently, there are gradually fewer conditions involving food scarcity and more involving excess food. Changes in income and relative prices generate measurable effects on the population's food intake patterns. Economic models have significant explanatory power for food demand, and the interactions between consumption, income, and prices are usually expressed as elasticity. However, the construction of some studies shows important shortcomings, especially for public policy application. This conceptual article discusses the potential contribution of food demand studies, suggesting improvements in the structural design of such studies with the inclusion of current nutritional concepts for redirecting the nutritional transition from under-nutrition to healthy eating, avoiding the present trend towards epidemic obesity. 相似文献
996.
Zhang J Mikolajczyk R Grewal J Neta G Klebanoff M 《American journal of epidemiology》2011,173(5):539-543
The individualized reference for defining small for gestational age (SGA) at birth has gained popularity in recent years. However, its utility on fetal assessment has not been evaluated. The authors compare an individualized with an ultrasound reference in predicting poor perinatal outcomes. Data from a large clinical trial in predominantly white US women (1987-1991) with singleton pregnancies (n = 9,526) were used. The individualized reference classified fewer SGA fetuses than the ultrasound reference, but the risks of adverse outcomes were similar between fetuses classified by both references. The risk increased substantially only when the percentiles fell below the 5th percentile (likelihood ratio positive at birth = 2.68 (95% confidence interval (CI): 2.00, 3.58) and 3.13 (95% CI: 2.34, 4.18) for ultrasound and individualized references, respectively). SGA fetuses defined by either the individualized or ultrasound reference alone had risk ratios of adverse outcomes of 1.91 (95% CI: 0.77, 4.77) and 1.18 (95% CI: 0.37, 3.77), respectively, compared with normal fetuses (the difference between these 2 risk ratios, P = 0.71). The authors conclude that neither the ultrasound-based nor the individualized reference does well in predicting adverse perinatal outcomes. The 5th percentile may be a better cutpoint than the 10th percentile in defining SGA. 相似文献
997.
Rajeev Gupta MD Manuel Villa MD Emanuel Agaba MD Garry Ritter PA MHA Cristina Sison Corrado P. Marini MD Rafael Barrera MD 《JPEN. Journal of parenteral and enteral nutrition》2013,37(3):368-374
Background: The incidence of obesity is rising, and an increasing number of obese patients are admitted to surgical intensive care units (SICUs). However, it is not clear whether obesity is an independent risk factor for increased morbidity and mortality in SICU patients. We examined the effect of obesity on morbidity and mortality in patients admitted to the SICU in this study. Method: We reviewed prospectively acquired SICU data in normal and obese patients with an SICU length of stay >24 hours. Comparability of the groups was assessed using a χ2 test or Fisher exact test, as appropriate, for categorical variables and analysis of variance (ANOVA) or the Kruskal‐Wallis test, as appropriate, for continuous variables. Results: Of the 1792 consecutive patients evaluated, 711 had a normal body mass index (BMI), and 993 were either preobese or obese. There was no statistically significant difference across the 5 BMI groups with respect to any of the 3 comorbidity indices (Acute Physiology and Chronic Health Evaluation III [APACHE III], Simplified Acute Physiology Score, or Multiple Organ Dysfunction Score). There was no statistically significant difference in the intensive care unit (ICU) length of stay and hospital length of stay or time‐to‐ICU mortality (log‐rank test P = .054) among the 5 BMI groups. A Cox regression analysis and backward elimination algorithm selected APACHE III to be the most important explanatory variable for survival time. Conclusion: Obesity does not affect the mortality of patients admitted to the SICU. We conclude that obesity cannot be used as an independent predictive mortality outcome variable in patients admitted to the SICU. 相似文献
998.
Florence?Samkange-ZeebEmail author Rafael?T.?Mikolajczyk Hajo?Zeeb 《Journal of community health》2013,38(2):293-300
Several western countries have reported increases of sexually transmitted diseases such as gonorrhea, syphilis and chlamydia since the mid-1990s, especially among teenagers 16–19 years old. We conducted a school-based survey to assess awareness and knowledge of STDs among students attending the 8th grade and above in Bremen and Bremerhaven, two cities in northern Germany. Between October and December 2011 students completed an anonymous questionnaire on awareness and knowledge of STDs in 8 different schools. To assess awareness of STDs, the students were asked to indicate which STDs they had heard of. Knowledge of STDs was assessed based on 4 general questions. Furthermore, comprehensive awareness of HPV was assessed based on 3 items. We assessed differences in HPV awareness and knowledge of STDs by key demographic variables such as age, gender and migrant background. A total of 1,148 students aged 12–20 years (response 28 %) completed the questionnaire. 31 % had a migrant background and 55 % were girls. Almost all students had heard of HIV/AIDS, but only 23 % of chlamydia and 13 % of HPV. Significantly more girls than boys had heard of HPV (18 vs. 8 %) and chlamydia (31 vs. 16 %). Generally, low levels of STD knowledge and awareness of HPV were observed. In multivariable analyses, age, gender, and ever having had sex were associated with both STD knowledge and awareness of HPV. HIV/AIDS remains the only sexually transmitted disease most students have heard of. Sex education at school needs to be broadened to include STDs other than HIV/AIDS. 相似文献
999.
Sergi Mas Anna Crescenti Patricia Gassó Ramon Deulofeu Rafael Molina Antonio Ballesta 《Nutrition and cancer》2013,65(1):107-114
Among the vegetables with anti-carcinogenic properties, members of the genus Brassica are the most effective at reducing the risk of cancer. This property may be explained by their principle bioactive compounds, isothiocyanates (ITCs). The aim of this study was to measure the amounts of ITCs in extracts from vegetables of the Brasssica genus and assay them for potency of induction of apoptosis in a colorectal cancer cell line (HT-29). ITCs were determined by the cyclocondensation assay with 1,2-benzenedithiol and induction of apoptosis by assessment of cell viability, caspase-3 activity and DNA fragmentation. Purple cabbage extract showed the highest ITC concentration per gram, fresh weight, followed by black cabbage and Romanesco cauliflower. At ITC concentrations of 7.08 μ g/mL these extracts decreased cell viability and induced caspase-3 and DNA fragmentation at 48h. Brussels sprouts showed the strongest effects on cell viability and caspase-3 activity. Varieties of Brassica Oleracea are rich sources of ITCs that potently inhibit the growth of colon cancer cells by inducting apoptosis. All the extracts showed anticancer activity at ITC concentrations of between 3.54 to 7.08 μ g/mL, which are achievable in vivo. Our results showed that ITC concentration and the chemopreventive responses of plant extracts vary among the varieties of Brassica Oleracea studied and among their cultivars. 相似文献
1000.
Vanshdeep Sharma Deborah B. Marin Eugene Sosunov Fatih Ozbay Rafael Goldstein George F. Handzo 《Journal of health care chaplaincy》2013,19(3):85-101
There is an acute need to define the specific skills that make chaplains integral to the healthcare team. This prospective study attempts to identify those skills that may be specific to chaplains, for whom no other member of the health care team has similar training, and to examine if these skills have a differential effect on patient satisfaction. A total of 59 interventions were identified and grouped into 10 categories by focus groups comprised of chaplains. Subsequently, Principal Component Analysis yielded two independent variables; Component 1 representing the “Religious/Spiritual” dimension, and Component 2 representing the “Psychosocial” dimension of chaplains’ work. The two components were used in an OLS regression model to measure patient satisfaction. Interventions that comprise the “Religious/Spiritual” dimension may be considered to be specific skills that chaplains contribute to patient care and these have a slightly stronger correlation with patient satisfaction than the interventions of the “Psychosocial” dimension. 相似文献