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21.
Objective: To develop and evaluate the psychometric properties (reliability, validity etc.) of a comprehensive Quality of Life (QOL) tool, for patients infected with the human immunodeficiency virus (HIV), that was adapted from a previously validated cancer tool. Design: Cross-sectional, patient completed written surveys and interviews. Setting: The Medical Centers serving HIV infected patients in the Los Angeles community including UCLA, community physicians, Veterans Affairs Medical Centers, and a County hospital: and additional data contributed from Johns Hopkins University Medical Center CMV Retinitis Clinic. Patients: Patients (n=318) with HIV infection including asymptomatic (37%), ARC (20%), AIDS (25%) and AIDS with Cancer (18%) receiving health services at one of the above sites. Measurements: The patients self-administered the newly developed instrument, the HOPES (HIVOverview ofProblems-EvaluationSystem), other QOL related tools including the Medical Outcomes Study instrument adapted for HIV (MOS-HIV) the Profile of Mood States (POMS), the Perceived Adjustment to Chronic Illness Scale (PACIS), and the Physical Activity Scale (PAS). Brief interview to assess the Karnofsky Performance Status Score (KPS). Measured sociodemographic characteristics included age, sex, race, HIV risk factor, education etc. Assessed medical history, current medications, HIV clinical classification. Main results: The sociodemographic and medical characteristics of the sample resemble those of the general population with HIV infection in this geographic area: 96% male, 28% nonwhite, 84% homosexual contact as risk factor, 75% receiving antiretroviral therapy. The adaptation of the cancer QOL instrument to HIV appears to have face and content validity according to patients and health professionals who care for HIV infected patients. Analyses of the psychometric properties found that the HOPES has a similar structure to its parent instrument following factor analyses which results in five summary scales representing the Physical, Psychosocial, Medical Interaction, Sexual and Significant Other/Partners domains in addition to a Global Score. Internal consistency of 35 subscales is high with a mean alpha coefficient of 0.82. Correlations of the HOPES summary scales with other QOL instruments are in the predicted directions. Comparing patients within the HIV clinical diagnostic categories on the HOPES Global, Physical, and Psychosocial Summary Scales indicates that Asymptomatic Patients have better QOL than symptomatic patients. This finding is also found in the other QOL instruments which provides evidence of construct validity. Conclusions: The HOPES is an excellent tool for identifying the problems and needs of patients with HIV infection and for assessing their quality of life. It is reliable, valid and acceptable to patients. The tool may be especially useful in developing a normative data base.This paper is dedicated to the memory of Jimmy Stophel who died of AIDS and whose sense of humour improved the quality of many people's lives.This research was supported in part by the UCLA AIDS Clinical Research Center and CARES Consultants. To obtain information about the HOPES, please contact C. A. Coscarelli Schag, CARES Consultants, 2210 Wilshire Blvd., Suite 359, Santa Monica, CA 90403, USA.  相似文献   
22.
The Paternity Testing Commission (PTC) of the International Society for Forensic Genetics has taken up the task of establishing the biostatistical recommendations in accordance with the ISO 17025 standards and a previous set of ISFG recommendations specific to the genetic investigations in paternity cases. In the initial set, the PTC recommended that biostatistical evaluations of paternity are based on a likelihood ratio principle – yielding the paternity index, PI. Here, we have made five supplementary biostatistical recommendations. The first recommendation clarifies and defines basic concepts of genetic hypotheses and calculation concerns needed to produce valid PIs. The second and third recommendations address issues associated with population genetics (allele probabilities, Y-chromosome markers, mtDNA, and population substructuring) and special circumstances (deficiency/reconstruction and immigration cases), respectively. The fourth recommendation considers strategies regarding genetic evidence against paternity. The fifth recommendation covers necessary documentation, reporting details and assumptions underlying calculations. The PTC strongly suggests that these recommendations should be adopted by all laboratories involved in paternity testing as the basis for their biostatistical analysis.  相似文献   
23.
Two groups of salivary proteins, basic Proline-rich Proteins (PRPs) and Histatins (Hsts) effectively interact with food tannins and form insoluble complexes that are stable under conditions similar to those in vivo. The proteins diminish transport of tannin across intestinal cells probably due to the formation of insoluble tannin-protein complexes. In contrast the transport of flavonoids is not affected by PRPs or Hsts. The proteins may act as scavenger molecules preventing intestinal uptake of tannins with their associated harmful effect but allowing absorption of flavonoids and exploitation of their beneficial properties.  相似文献   
24.
This study aimed to describe the results of findings from data collected with an HIV-specific health-related quality of life tool, and to examine the relationship between clinical and biological factors and health-related quality of life (HRQL). Data were collected as a cross-sectional, patient-completed assessment of health-related quality of life. Laboratory data were abstracted from the medical chart. Patients (n=318) with HIV infection including asymptomatic (37%), ARC (20%), AIDS (25%), and AIDS with cancer (18%) were receiving health services at one of the medical centres serving HIV-infected patients in the Los Angeles community, including UCLA, community physicians, Veterans Affairs Medical Centers, and a county hospital. Additional data were contributed by the Johns Hopkins University Medical Center CMV Retinitis Clinic. Symptomatic patients and patients with the lowest CD4 counts reported poorer HRQL than asymptomatic patients and patients with higher CD4 counts. However, medical and demographic variables explained only 35% of the variability of HRQL ratings in this sample of HIV-infected patients. While clinical status and Karnofsky performance status may be used to estimate the impact of HIV infection on HRQL, they are not a substitute for independent assessment of HRQL by the patient.This research was funded in part by the UCLA AIDS Clinical Research Center and CARES Consultants. To obtain more information about the HOPES, please contact the second author at CARES Consultants, 2210 Wilshire Blvd, Suite 359, Santa Monica CA 90403  相似文献   
25.
26.
Little is known about the family care of older adults in Mexico and the role of women in this process. To begin to fill this knowledge gap, this paper describes how a small sample of low-income women in one Mexico City neighborhood conceptualized the caregiver role and identified the forms of assistance they gave to their older relatives on a daily basis. A grounded theory approach was used to collect and analyze the data. Forty-one semi-structured qualitative interviews were conducted with female caregivers. The age of participants was between 19 and 83 years, and care recipients between 56 and 92 years. The relationship of caregiver to care recipient was wife, daughter, daughter-in-law, granddaughter, sibling, and other relative. The mean length of time providing care was 5 years. Most participants were not employed outside the home, and the median monthly household income was 2000 pesos. We found that caregiving was a life-changing event, with 27 of 41 participants viewing themselves as guardians. Caregivers' emphasis was on care recipients' emotional needs in order to provide “the most precious gift” of “time and attention.” Two forms of assistance were ‘keeping company’ and ‘watching out’ as safeguards against poor health or further decline in health. These findings increase the cultural understanding of caregiving in Mexico. Further research is needed to test the caregiving concepts identified in this study.  相似文献   
27.
Antimuscarinic agents are the primary pharmacologic treatment of overactive bladder (OAB), and objective clinical data are available in a range of formats including head-to-head studies, systematic reviews and adjusted indirect comparisons. This paper reexamines the various data available on the safety and efficacy of the antimuscarinics. Clinical studies determine whether one treatment is better than another, rather than examining which treatment is best for the individual patient. Favourable treatment outcome may not be attained because of unrealistic expectations of the patient, who may also be dissatisfied with the complications of the treatment. Comparisons between clinical studies on drug therapy for OAB may be complicated by the high placebo response rates. Variations exist in the study populations in terms of symptom severity and tolerance of adverse events, and the diverse methods of assessment employed. Apart from head-to-head studies, meta-analyses can be employed to compare different classes of drugs (lumping method) or individual drugs (splitting method) by pooling of clinical data. The adjusted indirect comparison method has been developed as a method to allow the outcome of two different trials to be compared. Overall, data from clinical trials indicate that the commonly used antimuscarinics have different tolerability and safety profiles but broadly similar efficacy profiles. Consequently, therapy should be tailored to individual patient needs rather than one drug fits all.  相似文献   
28.
Recent serologic, immunoprotection, and pathogenesis studies identified the Lig proteins as key virulence determinants in interactions of leptospiral pathogens with the mammalian host. We examined the sequence variation and recombination patterns of ligA, ligB, and ligC among 10 pathogenic strains from five Leptospira species. All strains were found to have intact ligB genes and genetic drift accounting for most of the ligB genetic diversity observed. The ligA gene was found exclusively in L. interrogans and L. kirschneri strains, and was created from ligB by a two-step partial gene duplication process. The aminoterminal domain of LigB and the LigA paralog were essentially identical (98.5 ± 0.8% mean identity) in strains with both genes. Like ligB, ligC gene variation also followed phylogenetic patterns, suggesting an early gene duplication event. However, ligC is a pseudogene in several strains, suggesting that LigC is not essential for virulence. Two ligB genes and one ligC gene had mosaic compositions and evidence for recombination events between related Leptospira species was also found for some ligA genes. In conclusion, the results presented here indicate that Lig diversity has important ramifications for the selection of Lig polypeptides for use in diagnosis and as vaccine candidates. This sequence information will aid the identification of highly conserved regions within the Lig proteins and improve upon the performance characteristics of the Lig proteins in diagnostic assays and in subunit vaccine formulations with the potential to confer heterologous protection.  相似文献   
29.
Divergent biases in ecologic and individual-level studies.   总被引:9,自引:0,他引:9  
Several authors have shown that ecologic estimates can be biased by effect modification and misclassification in a different fashion from individual-level estimates. This paper reviews and discusses ecologic biases induced by model misspecification; confounding; non-additivity of exposure and covariate effects (effect modification); exposure misclassification; and non-comparable standardization. Ecologic estimates can be more sensitive to these sources of bias than individual-level estimates, primarily because ecologic estimates are based on extrapolations to an unobserved conditional (individual-level) distribution. Because of this sensitivity, one should not rely on a single regression model for an ecologic analysis. Valid ecologic estimates are most feasible when one can obtain accurate estimates of exposure and covariate means in regions with internal exposure homogeneity and mutual covariate comparability; thus, investigators should seek out such regions in the design and analysis of ecologic studies.  相似文献   
30.
A questionnaire survey was conducted among 7,665 students and staff in the factory-operated industrial colleges in Shanghai, China. Response rate was 95.7 per cent. The proportion of smokers among the men was 50.5 per cent; only 0.33 per cent of the women reported they were smokers. Male smokers began smoking upon entering the work force, where social interaction encourages cigarette smoking. Seventy per cent of the male smokers smoked fewer than 10 cigarettes per day. Only 4.3 per cent perceived themselves as very addicted; 3.4 per cent reported they had no confidence in their ability to control the amount they smoke. The Chinese smokers are more likely to succeed in giving up cigarette smoking for at least one day, as well as for longer periods, compared to US smokers. The number of cigarettes smoked may be related to the individual's purchasing power. For China, strategic timeliness in legislative action and education is urgently needed to combat the high prevalence of cigarette smoking in males, at extremely high risk.  相似文献   
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