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11.
Blood donation behavior of Hispanics in the lower Rio Grande Valley   总被引:2,自引:0,他引:2  
WW Thompson 《Transfusion》1993,33(4):333-335
This study was designed to determine the blood donation behavior and attitudes of Hispanic residents of the Lower Rio Grande Valley for the purpose of developing promotional and educational approaches to enhance levels of donor participation. Personal interviews of 545 respondents were conducted in English and Spanish using quota sampling and standard intercept techniques at lower- and middle-income supermarkets in five cities during a payday weekend. A number of research hypotheses were established to test for demographic, behavioral, and attitudinal differences that were observed in donors and nondonors using chi-square analysis and multiple discriminant analysis. After analyzing the difference between Hispanics and non-Hispanics for blood donation rates, all non-Hispanics were eliminated from analysis, and the remaining 419 Hispanics were evaluated on the basis of their donor behavior. Donation among Hispanics was most likely to be by better- educated, English-speaking, higher-job-status individuals who had participated in a blood donation drive. Donors tend to have parent(s) who were donors, and they were also more likely to carry an organ donor card. Donors were found to vary in their behaviors as well as their attitudes and beliefs. Perceptions of a lack of safety in donating, the risk of contracting acquired immune deficiency syndrome, and the financial motivation of donors were most pronounced among Hispanics, which indicated a need for improved education on these issues.  相似文献   
12.
The random dot stereogram E (RDE) has been shown to be a simple and effective test for the detection of binocular abnormalities and defective visual acuity in children. We determined the validity of the RDE as a screening test for reduced visual acuity, amblyopia and strabismus in two separate populations of children.
A nonselective group of 100 school children (aged 5 to 15 years) who presented consecutively to the ophthalmology department at Auckland Public Hospital were tested with the RDE. All cases of amblyopia and strabismus were detected by the RDE. Similar screening with the RDE test of 168 preschool children (aged three to four years) in the community resulted in an unacceptably high over-referral rate. The test was unreliable in the preschool age group because of difficulty in distinguishing between test failure and non-cooperation with the test. The low positive predictive value of the test in the younger age group suggests the test to be unsuitable for preschool vision screening.  相似文献   
13.
BACKGROUND: Much has been written on ethical issues in dementia, but usually from the point of view of the various professionals involved. Whilst there has been an increasing amount of interest in the psychosocial problems that face the carers of people with dementia, the ethical nature of some of these problems has largely been ignored. OBJECTIVE: To review the literature on ethical issues in dementia from the perspective of the main, non-professional carers of people with dementia. METHOD: A systematic literature search using Medline, Clinpsych and CINAHL databases between 1982 and 2000. A pilot study of carers. RESULTS: The lay perspective provides both a wide variety of issues and unique approaches. Although in the literature quantitative research answers some questions, it is qualitative research that deepens our understanding of the issues from the perspective of carers. CONCLUSION: It is particularly qualitative research that brings out the ethical issues for carers, which tend to be more varied than the ethical issues raised in the professional literature. Awareness of such issues could inform and shape the support given to carers.  相似文献   
14.
This paper explores currently available and potential solutions to the common problem of meniscal injury and examines the question of repair or replacement. Knowledge of the structure of the meniscus is critical to these questions. The medial and lateral menisci are semicircular wedges of fibrocartilage lying within the knee joint. The peripheral 1/3 of each meniscus is vascularized and has the potential to heal. In contrast, the inner 2/3 has no blood supply and does not heal. The material and structural properties of each meniscus primarily serve to transfer load and absorb shock. Secondary functions include aiding joint stability, lubrication and proprioception. A meniscal tear is the most common knee injury. Traumatic vertical lesions occur in younger people while degenerative horizontal tears are present in older patients. Symptomatic injured menisci are assessed arthroscopically to determine the stability and vascularity of the tear. Stable vascular tears are left alone and will heal spontaneously. An unstable avascular tear will not heal and is best resected to a stable rim. Suitable unstable vascular tears may be successfully repaired with an arthroscopic inside‐out suture technique. Success rates average 80% but may vary from 60 to 90%, primarily dependent upon selection of the correct tear to repair. Despite the success of meniscal repair, partial meniscectomy is commonly performed as tears that are unsuitable for repair are frequently found. Unfortunately, even partial meniscectomy results in chondral damage and subsequent osteoarthritis. Thus, replacement of damaged tissue is ideal for chondroprotection. Meniscal allograft transplantation is an experimental procedure with little current clinical application. Animal trials revealed that transplanted tissue could attach and heal to the periphery as well as repopulate with host derived cells. However, human trials have been disappointing with 40–60% failure rates. Collagen based biosynthetic scaffolds have been used to successfully replace meniscal tissue in a canine model. In a subsequent human trial, newly formed tissue was seen at second look arthroscopy at 3 and 6 months. Unfortunately, no long‐term studies are available and once again, this is an experimental procedure only. Adjuncts to meniscal replacement include growth factor and gene therapy. Studies to date indicate that appropriate growth factors may enhance cellular repair. Cellular migration of peripheral fibroblastic meniscal cells is stimulated by IL‐1 whilst PDGF increases cellular proliferation. Contrasting this, cellular migration is stimulated by IGF‐1 and BMP in the central chondrocytic zone. Recently, gene transfer has been performed into meniscal cells in vitro. Additionally, direct transfer into meniscal tissue has been shown in vivo. Therefore, it may be possible to transfect meniscal cells with genes to stimulate protein production, which in turn could stimulate proliferation, and matrix production. Combining the technologies of biosynthetic scaffolds, cell culture, growth factor and gene therapy is the evolving science of meniscal tissue engineering (MTE). Biodegradable synthetic polymers may be fabricated into complex shapes. These polymer matrices act as a scaffold for cellular attachment and growth. Layered release of growth factors could enhance attachment, proliferation and matrix production. A polyglycolic acid scaffold was used to successfully repair meniscal defects in rabbits. Explant defects were also healed using fibrochondrocytes on a PGA scaffold in a canine model. A cell–polymer construct has been engineered to replace the sheep meniscus. Analysis showed gross, histological and biochemical similarities to the normal meniscus. This demonstrated the feasibility of regenerating meniscal tissue in vivo using adult cells in an immune‐competent model. The author is currently involved in MTE research.  相似文献   
15.
During (January) 1986–(May) 1988, we examined 272 eyes in 136 rhesus monkeys in the closed Cayo Santiago colony of the Caribbean Primate Research Center of the University of Puerto Rico. Seventy-eight eyes were less than 10 years of age. One hundred and ninety-four were aged 10–28 years. The fundi were examined and photographed. Fluorescein angiography was performed in some eyes. Selected cases were evaluated for acuity loss by recording of pattern-evoked retinal and cortical signals. Light and electron microscopy were used to evaluate the pigment epithelium of some animals. Thirty-eight percent of all eyes had posterior pole drusen. Incidence was highly age-related. When late-stage lesions were found, we did not see neovascularization, but late hyperfluorescence was consistent with degenerative scarring and atrophy. Electrophysiology demonstrated moderately reduced acuity in the presence of numerous macular drusen. Electrooculograms were low normal. Histopathology showed changes identical to those reported in human age-related macular degeneration. No eyes less than 10 years of age had confluent drusen or disciform-like lesions. The incidence of drusen in samples of some social groups was much higher than others.  相似文献   
16.
The use of defined protein and peptide antigens can overcome specificity limitations of purified protein derivatives in the detection of bovine tuberculosis when the antigens are used in blood-based tests. Since the use of these specific antigens as skin test reagents could have practical advantages, we investigated the potential of Mycobacterium bovis-specific antigens to stimulate delayed-type hypersensitivity (DTH) responses in cattle experimentally infected with M. bovis. A cocktail of the recombinant antigens ESAT-6, MPB83, and MPB64 failed to stimulate in vivo DTH in cattle that had been experimentally infected with M. bovis despite the fact that the antigens were recognized in vitro by the same animals. However, it was possible to stimulate antigen-specific bovine DTH responses by using ESAT-6 in combination with a synthetic bacterial lipopeptide. This lipopeptide stimulated the release of the proinflammatory cytokine tumor necrosis factor alpha from monocyte-derived bovine dendritic cells in vitro, thereby providing a possible mechanism for its DTH-enhancing properties.  相似文献   
17.
Bovine NK cells have recently been characterized and the present study describes the interaction between NK cells, antigen-presenting cells, and secreted mycobacterial proteins. Gamma interferon (IFN-gamma) production by NK cells was seen in approximately 30% of noninfected calves in response to the Mycobacterium tuberculosis complex-specific protein ESAT-6, MPP14 from Mycobacterium avium subsp. paratuberculosis, and purified protein derivative (PPD) from M. tuberculosis. In contrast, no response was induced by MPB70, which is another M. tuberculosis complex-specific secreted antigen. The production of IFN-gamma by NK cells in whole blood in response to ESAT-6 and MPP14 was demonstrated using intracellular staining together with surface labeling for the NK cell-specific receptor, NKp46, or CD3. Furthermore, the depletion of NK cells from peripheral blood mononuclear cells completely abolished the IFN-gamma production. The response was mediated through stimulation of adherent cells and was largely independent of contact between adherent cells and the NK cells. Neutralization of interleukin-12 only partly inhibited IFN-gamma production, showing that other cytokines were also involved. The demonstration of NK cell-mediated IFN-gamma production in young cattle provides an explanation for the nonspecific IFN-gamma response frequently encountered in young cattle when using the IFN-gamma test in diagnosis of mycobacterial infections.  相似文献   
18.
The role that maternal and fetal human leukocyte antigen (HLA) genes play in pregnancy is unknown, but it has been suggested that fetuses whose HLA alleles do not differ from maternal alleles (i.e. histocompatible fetuses) are more likely to be aborted than fetuses with HLA alleles that differ from maternal alleles (i.e. histoincompatible fetuses). To elucidate the role of HLA compatibility in pregnancy, we tested the hypothesis that couples who match for HLA alleles or haplotypes would have reduced fertility because only these couples could produce histocompatible fetuses. We conducted a 10 year prospective study of HLA matching and pregnancy outcome in 111 Hutterite couples, providing information on 251 pregnancies. A logistic regression analysis was performed to determine the effects of HLA matching at HLA regions and loci on pregnancy outcome (fetal loss versus delivery). Significantly increased fetal loss rates were observed among couples matching for the entire 16-locus haplotype (P = 0.002). Among the individual loci, loss rates were increased among couples matching for HLA-B (P = 0.019), HLA-C (P = 0.033) and the complement component, C4 (P = 0.043). We interpret these results as evidence that matching for the entire 16-locus haplotype and/or alleles at an HLA-B-linked locus confers significant risk for fetal loss.   相似文献   
19.
The Body Awareness Rating Scale (BARS) was developed to evaluate the treatment process of the Body Awareness Group Therapy. The BARS subscales proved to have high interrater reliability. A factor analysis revealed two factors which seemed to measure one awareness and one movement dimension. The BARS was sensitive to change. As hypothesized, the BARS improvement enlarged with increasing duration of treatment. At discharge the good BARS outcome patients had improved significantly more than the poor BARS outcome ones, both concerning symptoms and global psychopathology.  相似文献   
20.
Human immunodeficiency virus generates the accessory proteins Nef, viral infectivity factor (Vif), viral protein R, and viral protein U or viral protein X during viral replication in host cells. Although the significance of these accessory proteins is often lost in vitro, they are essential for viral pathogenesis in vivo. Therefore, these proteins have much potential as antiviral targets. Recent data reveal Vif perturbs an ill-defined antiviral pathway in host cells allowing HIV replication. These data highlight a common feature among HIV accessory proteins in manipulating the host to aid viral pathogenesis. Therefore, these new insights into Vif and other HIV accessory proteins are reviewed, emphasizing host cell interactions and new targets for therapeutic intervention.  相似文献   
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