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101.
《Chronobiology international》2013,30(5):1124-1134
Using structural equation modeling, it can be shown that long weekly working hours and work on weekends, nights, and in shifts have detrimental effects on psychovegetative health. Employees' reported subjective work-life balance also decreases with increasing number of hours worked/week, days worked on weekends, or at nights, and with working shifts. A decrease in work-life balance in turn increases the risk of psychovegetative impairments (PVIs). Thus, long and unusual working hours increase the risk of psychovegetative health impairments both directly and indirectly, moderated by the subjective work-life balance. In fact, the indirect effects of working time on PVIs via the work-life balance seem to be stronger than the direct effects. Results of a cross-validation study of four independent and representative samples from Germany and the European Union (N?>?50,000) indicate high structural stability of these results and thus an increased validity and range for generalization. (Author correspondence: )  相似文献   
102.
Retinal ischemic injury is an important cause of visual impairment. The loss of retinal ganglion cells (RGCs) is a key sign of retinal ischemic damage. A subset of RGCs expressing the photopigment melanopsin (mRGCs) regulates non-image-forming visual functions such as the pupillary light reflex (PLR), and circadian rhythms. We studied the effect of retinal ischemia on mRGCs and the non-image-forming visual system function. For this purpose, transient ischemia was induced by raising intraocular pressure to 120?mm Hg for 40?min followed by retinal reperfusion by restoring normal pressure. At 4 weeks post-treatment, animals were subjected to electroretinography and histological analysis. Ischemia induced a significant retinal dysfunction and histological alterations. At this time point, a significant decrease in the number of Brn3a(+) RGCs and in the anterograde transport from the retina to the superior colliculus and lateral geniculate nucleus was observed, whereas no differences in the number of mRGCs, melanopsin levels, and retinal projections to the suprachiasmatic nuclei and the olivary pretectal nucleus were detected. At low light intensity, a decrease in pupil constriction was observed in intact eyes contralateral to ischemic eyes, whereas at high light intensity, retinal ischemia did not affect the consensual PLR. Animals with ischemia in both eyes showed a conserved locomotor activity rhythm and a photoentrainment rate which did not differ from control animals. These results suggest that the non-image forming visual system was protected against retinal ischemic damage.  相似文献   
103.
Aging and demographic changes in Europe and other global economies have led to a discussion about postponing the legal retirement age; however, health and safety consequences for the workforce have not yet been examined. Thus, the aim of this study was to investigate the effects of lifetime exposure to shiftwork on health impairments and fitness for duty. Two samples of the police force from one of the states of the Federal Republic of Germany were used. One sample was collected in 2008–2009 with a self-administered Internet questionnaire (n?=?705); the other sample was derived from employment records provided by the police force of the same federal state for the years 2002–2009 (n?=?2460). Both samples contained information about the number of years worked in shiftwork across the entire working life and impairments to fitness for duty assessed by occupational physicians. Thus, the number of years of shiftwork until the diagnosis of the first reduction in fitness for duty could be calculated. Survival analyses were performed to estimate the risk (hazard rate) for experiencing a reduction in fitness for duty across lifetime exposure to shiftwork in years, controlling for age, sex, work type, and police district. Hazard estimates were compared across both samples to cross-validate the results. The findings indicated an increase in the risk of reduced fitness for duty with increasing number of years in shiftwork during the working life in both samples. The hazard rates followed an exponential trend, indicating a rapid increase in health impairments in particular beyond 20 yrs of shiftwork. These findings were consistent in both samples, collected with different methods and over different time periods, thus indicating high validity. Therefore, occupational stress factors, such as exposure to shiftwork, need to be taken into account when discussing the postponement of the legal retirement age. (Author correspondence: )  相似文献   
104.
ABSTRACT

Daily rhythms in light exposure influence the expression of behavior by entraining circadian rhythms and through its acute effects on behavior (i.e., masking). Importantly, these effects of light are dependent on the temporal niche of the organism; for diurnal organisms, light increases activity, whereas for nocturnal organisms, the opposite is true. Here we examined the functional and morphological differences between diurnal and nocturnal rodents in retinorecipient brain regions using Nile grass rats (Arvicanthis niloticus) and Sprague-Dawley (SD) rats (Rattus norvegicus), respectively. We established the presence of circadian rhythmicity in cFOS activation in retinorecipient brain regions in nocturnal and diurnal rodents housed in constant dark conditions to highlight different patterns between the temporal niches. We then assessed masking effects by comparing cFOS activation in constant darkness (DD) to that in a 12:12 light/dark (LD) cycle, confirming light responsiveness of these regions during times when masking occurs in nature. The intergeniculate leaflet (IGL) and olivary pretectal nucleus (OPN) exhibited significant variation among time points in DD of both species, but their expression profiles were not identical, as SD rats had very low expression levels for most timepoints. Light presentation in LD conditions induced clear rhythms in the IGL of SD rats but eliminated them in grass rats. Additionally, grass rats were the only species to demonstrate daily rhythms in LD for the habenula and showed a strong response to light in the superior colliculus. Structurally, we also analyzed the volumes of the visual brain regions using anatomical MRI, and we observed a significant increase in the relative size of several visual regions within diurnal grass rats, including the lateral geniculate nucleus, superior colliculus, and optic tract. Altogether, our results suggest that diurnal grass rats devote greater proportions of brain volume to visual regions than nocturnal rodents, and cFOS activation in these brain regions is dependent on temporal niche and lighting conditions.  相似文献   
105.
In order to analyze whether impairments to health and well‐being under flexible working hours can be predicted from specific characteristics of the work schedules, periodic components in flexible working hours and their interference with the circadian temperature rhythm were analyzed applying univariate and bivariate spectrum analyses to both time series. The resulting indicators of spectral power and phase shift of these components were then related to reported health impairments using regression analysis. The results show that a suppression of both the 24 and the 168 h components in the work schedules (i.e., a lack of periodicity) can be used to predict reported health impairments, and that if there are relatively strong 24 and 168 h components left in the work schedules, their phase difference with the temperature rhythm (as an indicator of the interference between working time and the circadian rhythm) further predicts impairment. The results indicate that the periodicity of working hours and the amount of (circadian) desynchronization induced by flexible work schedules can be used for predicting the impairing effects of flexible work schedules on health and well‐being. The results can thus be used for evaluating and designing flexible shift rosters.  相似文献   
106.
《Science activities》2013,50(2):69-72
Effective teaching is the art of getting information to the students' memory in an organized manner to facilitate later retrieval. Thanks to advances in cognitive science, one can talk of the science of teaching. A metaphor that captures the work of effective teachers is "teachers as knowledge engineers," which connotes that effective teachers understand the nature of knowledge and, by extrapolation, the nature of teaching and learning. When teachers take charge of knowledge, view it as a process, and understand how to work with it, they take charge of the knowledge-construction process and better help their students. This article discusses how science teachers use analogies as a means of organizing knowledge in their students' memory.  相似文献   
107.

Aims

The second most frequently reported post-treatment symptom in cancer survivors are concerns about impaired cognition. Despite numerous studies demonstrating significant impairments in a portion of survivors, information on effective treatments remains an emerging area of research. This study examined the effectiveness of a group-based cognitive rehabilitation intervention in cancer survivors.

Main methods

This study was a randomized, controlled study of a 7-week cognitive rehabilitation intervention delivered in group format. Participants were evaluated with subjective symptom questionnaires and objective neurocognitive tests prior to and following treatment.

Key findings

Twenty-eight participants (mean age 58 years) with a median of 3 years (± 6 years) post-primary/adjuvant treatment and various cancer sites (breast, bladder, prostate, colon, uterine) completed the study. Compared to baseline, the treatment group demonstrated improvements in symptoms of perceived cognitive impairments (p < .01), cognitive abilities (p < .01) and overall quality of life with regard to cognitive symptoms (p < .01) as measured by the FACT-Cog. The treatment group also improved on objective measures of attention (p < .05) and a trend toward improvement on verbal memory. Significant improvement was not observed on all cognitive tests.

Significance

A group based cognitive rehabilitation intervention in cancer survivors was effective for improving attention abilities and overall quality of life related to cognition. Results suggest that group based cognitive rehabilitation may be an effective intervention for treating cognitive dysfunction in cancer patients and should be further studied in a larger trial with an active control condition.  相似文献   
108.
Racism, Class and the Racialized Outsider offers a sympathetic yet critical and scholarly re-examination of historical working-class politics through a detailed analysis of ‘race’. It follows the historiographical and theoretical trail of previous radical scholars, like Nairn on English nationalism and the groundbreaking but ‘race-blind’ work of heavyweight socialist labour historians like Hobsbawm and Thompson. While there have been many seminal studies of the English working class, this book points to the failure of such histories to explore the significance of class as articulated through the lens of race. In revisiting and reworking these influential works, the book critically appraises the significant part played by racialized elements of the working class, including Irish Catholics and Jews who are shown to have occupied centre stage, forming the vanguard of early socialist movements and labour organizations. This was no accident and fed into subsequent multiracial and socialist internationalist movements.  相似文献   
109.
Gone Home challenges dominant representations of Appalachia as white, placing in the foreground the life histories of African Americans who hail from the coalfields of eastern Kentucky. The book reveals how mass migration shapes subjectivities, examining two generations of African Americans who migrated into and out of the coalfields between 1910 and 1970. The coalfields were a layover stop in an intergenerational migration from the rural South to urban centres in the North, Midwest, and West. This review reflects on the significance of the layover stop, both empirically and conceptually. One of the key contributions of Gone Home is to show how the layover stop was important not only in terms of time and place, but also in terms of collective identity. The review concludes by reflecting on interconnected themes of industrial ruination and intergenerational memory.  相似文献   
110.
Three sampling methods for estimating abundance and size of blue cod Parapercis colias were compared inside and outside Kapiti Marine Reserve, New Zealand (40° 49′ 31·77′′ S; 174° 55′ 02·87′′ E). Two baited methods, baited underwater video (BUV) and experimental angling (EA), were more efficient and had lower levels of estimate variation than diver‐based underwater visual census (UVC). The BUV and EA recorded more fish and of greater size ranges than UVC, and also had fewer zero count replicates. The BUV and EA methodologies revealed highly significant differences in abundance and size of fish between sites (reserve v. non‐reserve), whereas UVC revealed no such differences. These results indicate that BUV is likely to be the most accurate, cost‐effective and easy to use methodology for the surveying of carnivorous temperate reef fishes for future monitoring. It is noted, however, that new data acquired using the BUV methodology may need to be compared over a calibration period to data acquired using the UVC methodology to ensure that historical data sets derived from UVC still have validity and application for future monitoring activity.  相似文献   
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