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991.
The stratum corneum, which is the outermost layer of the skin, functions as an important barrier to maintain biological homeostasis. The multilamellar structures formed by intercellular lipids present in the stratum corneum are considered to play an important role in barrier function. Most intercellular lipids are unbound and can be extracted by organic solvents, but some intercellular lipids are covalently bound to cornified envelope proteins. Decreases in unbound lipid levels reduce the barrier function of the stratum corneum, but the relationship between bound lipid and the barrier function of the stratum corneum is not well understood. In this study, we examined the relationship between the amount of covalently bound ceramide, the main bound lipid, and the barrier function of the stratum corneum. A single dose of UVB irradiation (2 x MED), or continuous UVB irradiation (0.5 x MED/day for 14 days) to the back, or feeding with an essential fatty acid-deficient (EFAD) diet for 8 weeks caused a significant elevation of TEWL and a significant reduction in covalently bound ceramides in hairless rats. Transmission electron microscopy revealed that the intercellular multilamellar structures in the stratum corneum of treated rats were incomplete (folding, defects, unclear images) compared to the structures seen in the stratum corneum of non-UVB-irradiated and non-EFAD rats. These results suggest that the amount of covalently bound ceramides is highly correlated with the barrier function of the skin, and that covalently bound ceramides play an important role in the formation of lamellar structures, and are involved in the maintenance of the barrier function of the skin.  相似文献   
992.
Cushing's syndrome (CS) is a rare disorder, especially in older people. Loss of brain volume and neurocognitive impairment of varying degrees has been demonstrated in patients with CS. However, there is a large difference between the median age of presentation of CS and that of Alzheimer's disease. We herein report a case of a patient with Alzheimer's disease complicated by elderly‐onset CS who had undergone surgical treatment for adrenal hyperplasia. Surgical correction of hypercortisolism seems to have slowed the progression of brain volume loss and cognitive dysfunction and improved psychiatric symptoms such as visual hallucination, restlessness, and psychomotor excitement. These improvements have remarkably reduced the burden on the patient's caregivers. The present case suggests that subclinical CS may be present, particularly in rapidly progressive dementia, and that surgical treatment of CS for neuropsychiatric symptoms is useful.  相似文献   
993.
Bisphenol A (BPA), one of the most common environmental endocrine disruptors, has been recognized to have wide adverse effects on the brain development and behavior. These adversities are related to its ability to bind estrogen receptor (ER) with subsequent alteration of its expression in the target areas. However, very little is known about whether BPA exposure also affects ER phosphorylation and its translocation to nucleus during postnatal development, two critical steps for its function. Here, we found that during development from postnatal day 7 (P7) to P21, the alpha subtype of ER (ERα) in the hippocampus of male rats experienced remarkable alterations in terms of its expression, phosphorylation and translocation to nucleus. Exposure to low level of BPA had bidirectional, development‐dependent effects on the expression of ERα mRNA and protein, but decreased ERα phosphorylation and impaired its translocation to nucleus throughout the period investigated. Treatment with low dose of ICI 182,780 (ICI), an ER antagonist to block the binding of ER with BPA, reversed the altered ERα following BPA exposure, highlighting critical involvement of ER. Moreover, ICI treatment rescued the hippocampus‐dependent behavioral deficits in the adult rats experiencing early‐life BPA exposure. Overall, our results indicate that BPA interferes with the ERα signaling in the developing hippocampus in an ER‐dependent manner, which may underlie its adverse behavioral and cognitive outcomes in adult animals. © 2014 Wiley Periodicals, Inc.  相似文献   
994.
A. Matsumoto  Y. Arai 《Brain research》1977,129(2):375-378
We have investigated the nuclear binding of [3H]oestradiol in the neonatal rat brain. The nuclear bound receptor, defined as the diethylstilboestrol (DES) suppressed nuclear bound radioactivity, showed similar sedimentation properties and time course to nuclear bound steroid receptors in other target tissues. After intracerebral injection we found that nuclear binding of [3H]oestradiol was localized to the hypothalamic/amygdaloid region with relatively little binding in cortical and cerebellar regions. After subcutaneous injection there was less difference between the hypothalamic and cortical regions, though there was still very low binding in the cerebellum. A deficit in nuclear binding of [3H]oestradiol was found in the hypothalamic amygdaloid region of the male compared to the female, which was dependent on the presence of the neonatal testis. We also found that unlabelled testosterone reduced the nuclear binding of [3H]oestradiol when given 3 h before the radioactive steroid, and this reduction was seen predominantly in the hypothalamic/amygdaloid region. The non-aromatizable androgen, 5α-dihydrotestosterone, was without effect on [3H]oestradiol binding.After injection of [3H]testosterone, receptor bound radioactivity was found exclusively in nuclei from the hypothalamic/amygdaloid region, this radioactivity was competed out by DES and testosterone but not by dihydrotestosterone. This study provides evidence that neurally aromatized androgen may bind to an oestrogen receptor in the neonatal hypothalamic/amygdaloid region and effect its translocation into the cell nucleus.  相似文献   
995.
996.
Ruptured vertebrobasilar dissecting aneurysm is usually treated surgically because rebleeding negatively affects outcome. However, the risk of rebleeding decreases markedly once several hours have passed from the initial bleeding. Moreover, surgery-related complications are not rare. We describe seven patients with ruptured vertebrobasilar dissecting aneurysm. To prevent rebleeding during the acute stage, we treated all seven patients conservatively with fentanyl instead of emergency surgery. During the follow-up period (mean 20 months), no patient suffered rebleeding. Conservative treatment with fentanyl administration may be a good option for management of ruptured vertebrobasilar dissecting aneurysm during the acute stage.  相似文献   
997.
998.
Three Japanese adolescents with chronic hepatitis C were treated by direct‐acting antivirals (DAAs). No adverse events or laboratory abnormalities were observed during and after DAA therapy, and a sustained virological response was achieved in all cases. The emotional functioning of the patients and their mothers were improved after DAA therapy.  相似文献   
999.
1000.
OBJECTIVE: Granulocyte-colony stimulating factor (G-CSF) accelerates repair following myocardial infarction (MI). Recently, the beneficial effects of post-MI administration of G-CSF were reported to be mediated by direct activation of the Jak-Stat pathway in cardiomyocytes. Our aim was to test the hypothesis that bone marrow-derived cells recruited into the infarcted myocardium are the primary mediators of the beneficial effects by G-CSF. METHODS AND RESULTS: MI was induced using a 30-min ischemia-reperfusion protocol (day 0) in 40 rabbits treated with G-CSF (10 microg/kg/day from days 3 to 7) or saline. Another 40 rabbits received the same G-CSF or saline protocol but also received AMD3100 (200 microg/kg/day), a specific inhibitor of CXCR4. On day 28 post-MI, left ventricular ejection fractions and end-diastolic dimensions were significantly better in the G-CSF group than in the control saline group, and the scar area/left ventricular wall area ratio was significantly smaller in the G-CSF group. G-CSF administration also led to increased mobilization of CXCR4+ bone marrow cells, including RAM11+ macrophages, into infarcted areas. And within those areas there was significant upregulation of expression of stromal cell-derived factor (SDF)-1, a chemoattractant of circulating CXCR4+ cells, as well as of the collagenase matrix metalloproteinase-1. AMD3100 significantly inhibited all of these beneficial effects of G-CSF, but did not affect the upregulation of SDF-1 or phospho-Stat3. CONCLUSION: Recruitment of CXCR4+ cells into infarcted myocardial tissues via stimulation of the CXCR4/SDF-1 axis plays a critical role in the beneficial effects of G-CSF.  相似文献   
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