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221.
Four experiments were performed to evaluate the effects of developmental protein deprivation on the behavioral response of adult rats to treatments known to affect central nervous system catecholamine systems. Results showed no group differences between protein malnourished and control animals in locomotor responsiveness to d- or l-amphetamine, recovery from behavioral asymmetry produced by a unilateral lesion of the substantia nigra, or in the development of response patterns indicative of denervation supersensitivity. However, a dose-dependent diminution in the ability of apomorphine to produce stereotyped behavior was noted in the malnourished group, suggesting that a class of brain dopamine receptors may be impaired or may have undergone homeostatic modification as a result of the undernutrition procedure.  相似文献   
222.
Rats whose mothers were maintained on either a 25% casein diet or an 8% casein diet and who were provided the same diet after weaning were tested on delayed spatial alternation or on one of a series of spatial localization problems using the Morris maze (Morris, 1981). Malnourished rats demonstrated perseverative deficits in the form of strings of consecutive errors on the delayed spatial alternation. Performance in the Morris maze indicated spatial localization ability and spatial memory processes were not impaired by chronic malnutrition in rats. The data suggest that complex processing of spatial information that includes flexible use of place cues over short intervals is impaired by malnutrition, while spatial localization per se and spatial mapping are not affected.  相似文献   
223.
To extend our investigation of the anatomy of sensory systems in highly adapted aquatic and terrestrial mammals, we have analyzed the distribution of a particular population of efferent neurons in the cetacean and human primary auditory cortex using an antibody to non-phosphorylated neurofilament protein (SMI32). The neurofilament protein triplet is differentially distributed within neuronal subpopulations in the primate and cetacean neocortex. In primates, it appears that the somatodendritic domain of a subset of pyramidal neurons furnishing specific corticocortical connections contains high concentrations of neurofilament protein. In the human primary auditory cortex these neurons are located in layers III, V and VI, whereas in cetaceans they are concentrated almost exclusively in the cortical efferent layer IIIc/V. Previous analyses have shown that SMI32 immunoreactivity in the cetacean neocortex is uniformly distributed among functionally different areas, while in human neocortex, the distribution of SMI32-positive neurons exhibit a high degree of regional and laminar specialization that is correlated with the functional and anatomical diversity of the cortical areas. In addition, the overall distribution of SMI32-immunoreactive neurons in the cetacean neocortex is comparable to that observed in paralimbic areas of the human, suggesting that the cetacean neocortex has retained many features of phylogenetically older cortical regions.  相似文献   
224.
Cyanobacterial blooms in eutrophic freshwater is a global threat to the functioning of ecosystems, human health and the economy. Parties responsible for the ecosystems and human health increasingly demand reliable predictions of cyanobacterial development to support necessary decisions. Long-term data series help with identifying environmental drivers of cyanobacterial developments in the context of climatic and anthropogenic pressure. Here, we analyzed 13 years of eutrophication and climatic data of a shallow temperate reservoir showing a high interannual variability of cyanobacterial development and composition, which is a less occurring and/or less described phenomenon compared to recurrant monospecific blooms. While between 2007–2012 Planktothrix agardhii dominated the cyanobacterial community, it shifted towards Microcystis sp. and then Dolichospermum sp. afterwards (2013–2019). The shift to Microcystis sp. dominance was mainly influenced by generally calmer and warmer conditions. The later shift to Dolichospermum sp. was driven by droughts influencing, amongst others, the N-load, as P remained unchanged over the time period. Both, climatic pressure and N-limitation contributed to the high variability of cyanobacterial blooms and may lead to a new equilibrium. The further reduction of P-load in parallel to the decreasing N-load is important to suppress cyanobacterial blooms and ameliorate ecosystem health.  相似文献   
225.
The national youth and young adult tobacco prevention mass media campaign, truth®, relaunched in 2014 with the goal of creating “the generation that ends smoking.” The objective of this study was to assess whether the strategy of airing truth ads during popular, culturally relevant televised events was associated with higher ad and brand awareness and increases in social media engagement. Awareness of six truth advertisements that aired during popular television events and self-reported social media engagement were assessed via cross-sectional online surveys of youth and young adults aged 15–21 years. Social engagement was also measured using separate Twitter and YouTube metrics. Logistic regression models predicted self-reported social engagement and any ad awareness, and a negative binomial regression predicted the total social media engagement across digital platforms. The study found that viewing a popular televised event was associated with higher odds of ad awareness and social engagement. The results also indicate that levels of social media engagement for an event period are greater than for a nonevent period. The findings demonstrate that premiering advertisements during a popular, culturally relevant televised event is associated with higher awareness of truth ads and increased social engagement related to the campaign, controlling for variables that might also influence the response to campaign messages.  相似文献   
226.
There are no studies which have compared the risk of severe COVID-19 and related mortality between transplant recipients and nontransplant patients. We enrolled two groups of patients hospitalized for COVID-19, that is, kidney transplant recipients (KTR) from the French Registry of Solid Organ Transplant (n = 306) and a single-center cohort of nontransplant patients (n = 795). An analysis was performed among subgroups matched for age and risk factors for severe COVID-19 or mortality. Severe COVID-19 was defined as admission (or transfer) to an intensive care unit, need for mechanical ventilation, or death. Transplant recipients were younger and had more comorbidities compared to nontransplant patients. They presented with higher creatinine levels and developed more episodes of acute kidney injury. After matching, the 30-day cumulative incidence of severe COVID-19 did not differ between KTR and nontransplant patients; however, 30-day COVID-19-related mortality was significantly higher in KTR (17.9% vs 11.4%, respectively, p = .038). Age >60 years, cardiovascular disease, dyspnea, fever, lymphopenia, and C-reactive protein (CRP) were associated with severe COVID-19 in univariate analysis, whereas transplant status and serum creatinine levels were not. Age >60 years, hypertension, cardiovascular disease, diabetes, CRP >60 mg/L, lymphopenia, kidney transplant status (HR = 1.55), and creatinine level >115 µmol/L (HR = 2.32) were associated with COVID-19-related mortality in univariate analysis. In multivariable analysis, cardiovascular disease, dyspnea, and fever were associated with severe disease, whereas age >60 years, cardiovascular disease, dyspnea, fever, and creatinine level>115 µmol/L retained their independent associations with mortality. KTR had a higher COVID-19-related mortality compared to nontransplant hospitalized patients.  相似文献   
227.
Lynch syndrome is the most common form of hereditary colorectal cancer. Screening programs have reduced colon cancer mortality. Despite intensive surveillance, the cumulative risk of developing colorectal cancer is substantial. Identification of modifiable factors has the potential to improve outcome of surveillance. Our article will review current guidelines for Lynch syndrome and how to perform colonoscopy. High-quality surveillance colonoscopy should be performed in an experimented center every 1–2 years, starting at the age of 20–25 years. Colonoscopy should include meticulous inspection and precise removal of all polyps, with special attention to the right colon especially of flat lesions. News endoscopic techniques, such as chromoendoscopy, were developed and recommended to improve the detection of adenomas, particularly of flat adenomas, and minimize the risk of developing interval cancer. Finally, educational intervention in a surveillance program is essential for optimizing screening including adherence.  相似文献   
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ABSTRACT:: Self-healing juvenile cutaneous mucinosis (SHJCM) is a rare disorder of unknown origin, which occurs in children in good health. It is characterized by the multiplication of transient cutaneous papules and nodules, mainly located on the head and periarticular areas that spontaneously resolve. Histological features of SHJCM have been well described; therefore, the diagnosis is usually made easily when papules are biopsied. We report a series of 3 new cases of SHJCM presenting mainly with nodular lesions. Histological examination of these nodules showed either lesions consistent with nodular or proliferative fasciitis or nonspecific panniculitis. Mucinous deposits were present but often inconspicuous, so could be disregarded. We wanted to emphasize this misleading presentation because a biopsy for histological examination is always mandatory in cases of proliferating nodules to rule out malignant tumors. Therefore, the diagnosis always requires discussion between pathologists and clinicians to rapidly reassure the parents and avoid inappropriate therapy.  相似文献   
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