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981.
This study has 2 objectives: (a) to explore typical paths of cognitive development associated with aging, terminal decline, and dementia and (b) to promote and illustrate an individual-oriented approach to the study of cognitive aging based on longitudinal panel data from a population-based sample (N = 500; age range-sub(T1)= 60-80, where T refers to time) tested at 3 occasions 5 years apart. Results document interindividual differences in multivariate patterns of change. Although cognitive changes generally covary, the present study indicates that subgroups of individuals develop along different paths characterized by selective changes in subsets of cognitive functions. Typical progression of dementia followed a developmental cascade from low declarative memory, via low functioning across all observed cognitive measures, to dementia diagnosis, and finally, death. 相似文献
982.
Chronic fatigue syndrome (CFS) is an important condition confronting patients, clinicians, and researchers. This article provides information concerning the need for appropriate diagnosis of CFS subtypes. We first review findings suggesting that CFS is best conceptualized as a separate diagnostic entity rather than as part of a unitary model of functional somatic distress. Next, research involving the case definitions of CFS is reviewed. Findings suggest that whether a broad or more conservative case definition is employed, and whether clinic or community samples are recruited, these decisions will have a major influence in the types of patients selected. Review of further findings suggests that subtyping individuals with CFS on sociodemographic, functional disability, viral, immune, neuroendocrine, neurology, autonomic, and genetic biomarkers can provide clarification for researchers and clinicians who encounter CFS characteristically confusing heterogeneous symptom profiles. Treatment studies that incorporate subtypes might be particularly helpful in better understanding the pathophysiology of CFS. This review suggests that there is a need for greater diagnostic clarity, and this might be accomplished by subgroups that integrate multiple variables including those in cognitive, emotional, and biological domains. 相似文献
983.
This review identified 1275 studies examining cognitive deficits in people with schizophrenia, published between 1990 and
2003. Data from 113 studies (4365 patients and 3429 controls) were combined in a meta-analysis carried out on the five cognitive
domains of IQ, memory, language, executive function, and attention. Studies were excluded where they lacked a suitable control
group or failed to present complete information. In all five cognitive domains, analysis indicated a consistent trend for
patients to perform more poorly than healthy controls, with significant heterogeneity across studies. Sources of heterogeneity
were analyzed and a need to ensure more appropriate composition of patient and control groups and to adopt a more refined
and methodologically correct, hypothesis-driven approach was identified. 相似文献
984.
The present study evaluated the effect of chronic cold stress on intestinal epithelial cell proliferation and inflammation. Male Wistar rats were subjected to cold exposure for three weeks. At the end of the cold exposure, intestinal cell proliferation, luminal nitrite and protein levels, intestinal myeloperoxidase activity and mast cell numbers were evaluated. Severely compromised proliferation rate of the crypt-base cells was observed under chronic stress conditions. Cells isolated from stressed rats showed a decreased DNA content in villus and lower villus cell fractions and an increased DNA content in the crypt cells, as compared to controls. Chronic cold stress resulted in increased luminal nitrite, luminal protein levels, and intestinal myeloperoxidase activity. The number of mast cells was significantly elevated under chronic stress conditions. Chronic cold stress resulted in a compromised intestinal epithelial cell proliferation rate and induced inflammation in the rat small intestine, through the combined action of nitric oxide, neutrophils and mast cells. 相似文献
985.
Almost all research on aggression in adolescent romantic relationships makes use of 1-time, retrospective assessment methods. In the present research, the authors compared data on the experience of adolescent relationship aggression (physical aggression and threatening behavior) collected from 125 high school students via 2 methods: (a) a 1-time, 2-month retrospective assessment and (b) a cumulative method based on four 2-week retrospective assessments, each spaced 2 weeks apart. For the cumulative method, data from the 4 assessments were aggregated to cover the same time period as the single, 2-month retrospective assessment. A greater proportion of the sample (48.0%) reported experiencing physical aggression using the cumulative method compared with the single, 2-month retrospective method (27.0%). The prevalence of threatening behavior was also higher using the cumulative method (48.8% vs. 24.8%). Adolescent trauma and anxiety symptoms correlated more strongly with physical aggression data derived from the cumulative method than from the 1-time assessment method. 相似文献
986.
The main purpose of the current research was to develop an abbreviated form of the Dyadic Adjustment Scale (DAS) with nonparametric item response theory. The authors conducted 5 studies, with a total participation of 8,256 married or cohabiting individuals. Results showed that the item characteristic curves behaved in a monotonically increasing function for all items of the brief 4-item version of the DAS (DAS-4). The DAS-4 proved to be informative at all levels of couple satisfaction. Compared with the 32-item version of the DAS (DAS-32), it was as effective in predicting couple dissolution and was significantly less contaminated by socially desirable responding. In addition, structural equation modeling demonstrated that the underlying latent construct measured by the DAS-4 was very stable over a 2-year period. This brief version has the advantage of being less time consuming and constitutes a promising alternative to the original DAS-32 for clinicians and researchers. 相似文献
987.
Although hypochondriasis is associated with the costly use of unnecessary medical resources, this mental health problem remains largely neglected. A lack of clear conceptual models and valid measures has impeded accurate assessment and hindered progress. The Multidimensional Inventory of Hypochondriacal Traits (MIHT) addresses these deficiencies with scales that correspond to a 4-factor model. The MIHT was built with construct validity as a guiding principle and began with an item pool that broadly assessed dimensions identified in the literature. The items were administered to large samples; factor analyses of the responses led to item pool revisions and scale refinements. Multiple studies validated the final MIHT scales and 4-factor model; these findings suggest that the MIHT will contribute to theory and research. 相似文献
988.
McConkie-Rosell A Finucane B Cronister A Abrams L Bennett RL Pettersen BJ 《Journal of genetic counseling》2005,14(4):249-270
These recommendations describe the minimum standard criteria for genetic counseling and testing of individuals and families
with fragile X syndrome, as well as carriers and potential carriers of a fragile X mutation. The original guidelines (published
in 2000) have been revised, replacing a stratified pre- and full mutation model of fragile X syndrome with one based on a
continuum of gene effects across the full spectrum of FMR1 CGG trinucleotide repeat expansion. This document reviews the molecular
genetics of fragile X syndrome, clinical phenotype (including the spectrum of premature ovarian failure and fragile X-associated
tremor-ataxia syndrome), indications for genetic testing and interpretation of results, risks of transmission, family planning
options, psychosocial issues, and references for professional and patient resources. These recommendations are the opinions
of a multicenter working group of genetic counselors with expertise in fragile X syndrome genetic counseling, and they are
based on clinical experience, review of pertinent English language articles, and reports of expert committees. These recommendations
should not be construed as dictating an exclusive course of management, nor does use of such recommendations guarantee a particular
outcome. The professional judgment of a health care provider, familiar with the facts and circumstances of a specific case,
will always supersede these recommendations. 相似文献
989.
Claes E Evers-Kiebooms G Denayer L Decruyenaere M Boogaerts A Philippe K Legius E 《Journal of genetic counseling》2005,14(5):349-363
This prospective study evaluates emotional functioning and illness representations in 68 unaffected women (34 carriers/34
noncarriers) 1 year after predictive testing for BRCA1/2 mutations when offered within a multidisciplinary approach. Carriers had higher subjective risk perception of breast cancer
than noncarriers. Carriers who did not have prophylactic oophorectomy had the highest risk perception of ovarian cancer. No
differences were found between carriers and noncarriers regarding perceived seriousness and perceived control of breast and
ovarian cancer. Mean levels of distress were within normal ranges. Only few women showed an overall pattern of clinically
elevated distress. Cancer-specific distress and state-anxiety significantly decreased in noncarriers from pre- to posttest
while general distress remained about the same. There were no significant changes in distress in the group of carriers except
for ovarian cancer distress which significantly decreased from pre- to posttest. Our study did not reveal adverse effects
of predictive testing when offered in the context of a multidisciplinary approach. 相似文献
990.
Streiffer R 《Kennedy Institute of Ethics journal》2005,15(4):347-370
Experiments involving the transplantation of human stem cells and their derivatives into early fetal or embryonic nonhuman animals raise novel ethical issues due to their possible implications for enhancing the moral status of che chimeric individual. Although status-enhancing research is not necessarily objectionable from the perspective of the chimeric individual, there are grounds for objecting to it in the conditions in which it is likely to occur. Translating this ethical conclusion into a policy recommendation, however, is complicated by the fact that substantial empirical and ethical uncertainties remain about which transplants, if any, would significantly enhance the chimeric individual's moral status. Considerations of moral status justify either an early-termination policy on chimeric embryos, or, in the absence of such a policy, restrictions on the introduction of pluripotent human stem cells into early-stage developing animals, pending the resolution of those uncertainties. 相似文献