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1.
Adolescents are at increasing risk for HIV infection in Mexico. Research on gender differences in risk behaviors and determinants is needed to develop effective HIV prevention interventions targeting Mexican adolescents. This study examined gender differences in the likelihood of unprotected sex and theoretical correlates among high school students in the border city of Tijuana. Three hundred seventy high-school students completed a face-to-face interview and a self-administered survey. Differences in sexual initiation, condom use, intentions to use condoms in the future, and attitudes towards condoms in this population were assessed. Although male students initiated sexual practices earlier than females, females were more likely to have unprotected sex. Females perceived themselves as more likely to avoid unprotected sex in the future and held more favorable attitudes about condoms. The results suggest that stereotypical gender roles and communication barriers place Tijuana female high school students at higher risk for HIV infection than their male peers.  相似文献   
2.
M J Grubman  M Zellner  J Wagner 《Virology》1987,158(1):133-140
The cross-reactivity of proteins coded for by the seven serotypes of foot-and-mouth disease virus (FMDV) was assessed by reaction of infected cell lysates with polyclonal and monospecific antisera against the structural and nonstructural proteins of FMDV type A12 strain 119ab. It was shown that the homologous polypeptides from most serotypes are antigenically related. The least cross-reactivity occurred between VP1, VP3, and the protease (3C) of type A12 and South African Territories types 1 and 3. There was also a reduced degree of reactivity of A12 VP1 serum with VP1 from some A subtypes and the other serotypes. Comparison of FMDV proteins with polypeptides from other picornaviruses by a radioimmune binding assay revealed a low level of reactivity of antisera against some A12 polypeptides with encephalomyocarditis virus (EMCV) infected cell lysates but no reactivity with bovine enterovirus type 1 and swine vesicular disease virus infected cells. The same EMCV proteins were immunoprecipitated by the various reactive A12 antisera, but the reaction was abolished if the lysate from EMCV infected cells was denatured prior to immunoprecipitation.  相似文献   
3.
Prevention Science - Involving youth in developing and implementing prevention programs to reduce sexual violence (SV) has the potential to improve prevention outcomes. However, there has been...  相似文献   
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BACKGROUND: Subtherapeutic drug dosing may be even more dangerous than overdosage, especially for intensive care patients requiring hemofiltration. PROPOSAL: According to Dettli's fundamental equation, body clearance of any drug (Cl) is a linear function of creatinine clearance (Cl = Cl anur + a x C(Cr)), with [a = (Cl norm - Cl anur)/C(Cr), norm]. We propose to individualize drug dosage during high-flux hemofiltration by basing it on Dettli's equation and on total C(Cr) (C(Cr) tot = C(Cr) ren + C(Cr) filt). Using this approach, drug clearance will eventually be overestimated for drugs with substantial tubular secretion and for high-efficiency hemofiltration (C(Cr) tot > 30 ml/min). CONCLUSION: In patients undergoing hemofiltration, the total C(Cr) approach might be a practical alternative to standardized dosing schemes for deriving an individualized dosage from published pharmacokinetic data and functions.  相似文献   
6.
Spanish and American participants rated how much they liked three common sweets and three common beverages listed on a questionnaire. They also named the food or drink for which they had the strongest craving. Cross-cultural comparisons in liking were almost always consistent with cross-cultural comparisons in rates of exposure. In both cultures, among subjects whose cravings could be so classified more females (about 5/8) craved sweet foods than savories and more males (about 5/8) craved savories than sweets. Among sweet cravers, chocolate craving was much more frequent for American females (44.6%) than for American males (17.4%), but no such gender difference occurred for the Spaniards (28.6 and 22.2%). The results argue for a possible physiological basis for the gender differences in sweet/savory craving but against a physiological basis for chocolate craving.  相似文献   
7.
BACKGROUND: Dialysis patients frequently present with debilitating coronary artery disease but are regarded as challenging patients for coronary artery bypass grafting. METHODS: The operative, early postoperative, and late results of 44 dialysis patients undergoing coronary artery bypass grafting from 1984 to 1997 were retrospectively reviewed. RESULTS: Compared with patients in The Society of Thoracic Surgeons database who underwent coronary artery bypass grafting, only cerebrovascular accident and postoperative cardiac arrest occurred more frequently in dialysis patients. However, 73% experienced some type of complication. Operative mortality was 11.4%. Decreased left ventricular ejection fraction and severe distal disease were predictive of increased operative mortality. New York Heart Association angina class fell from 2.8 to 1.5, and New York Heart Association congestive heart failure class fell from 2.6 to 1.8. Overall quality-of-life scores did not improve; however, walking distances remained consistently improved. Actuarial survival at 5 years was 32.0%+/-12.0%. Five-year survival was 0% for smokers and 83.6%+/-7.6% for nonsmokers (p = 0.0142). Causes of late death were myocardial infarction (4), sepsis (1), subdural hematoma (1), stroke (1), and unknown (6). CONCLUSIONS: Coronary artery bypass grafting should be avoided in dialysis patients with severe diffuse disease. A smoking history is associated with poor outcome. Coronary artery bypass grafting in dialysis patients is associated with a higher incidence of complications but can be performed with an acceptable operative mortality and is associated with good symptomatic relief of angina and heart failure.  相似文献   
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Women may have difficulty maintaining smoking cessation efforts due to negative affect and fear of weight gain. Dieting smokers who rely on cigarettes for affect regulation and weight management may be especially prone to weight gain and smoking relapse following initial smoking abstinence. The present study, which included 82 women smokers, assessed the relationship between dieting status, self-efficacy, and temptation to smoke and eat following a depressing or elating mood induction. Women with high levels of dietary restraint (i.e., more dieting behavior) had more confidence in their ability to refrain from smoking when in the elated mood condition, and they were more tempted to smoke when in the depressed condition. At low levels of dietary restraint (i.e., less dieting behavior), depressed or elated mood condition appeared to have little impact on women's confidence to refrain from smoking or their temptation to smoke. Dieting status seems to moderate the impact of positive and negative mood states, especially with respect to women's smoking behavior. These findings may have implications for dieters who are trying to quit smoking and also maintain their weight.  相似文献   
10.
Certain colors are seen as corresponding to, and thus appropriate to, certain odors (e.g., red for cherry odor). When colors accompany odors, our perceptions of the odors are changed. Appropriate colors often affect our perception of the odors differently from inappropriate colors. This paper discusses the literature on color–odor correspondences including possible causes of these correspondences. It then reviews findings on the influence of color on odor identification, odor discrimination, odor intensity, and odor pleasantness. Color's effect on both orthonasal and retronasal olfaction is discussed. A model for how color exerts its effects on odor is proposed.  相似文献   
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