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101.
A large number of disorders affecting the masticatory system can cause restriction of mouth opening. The most common conditions related to this problem are those involving the temporomandibular joint (TMJ) and the masticatory muscles, when facial pain also is an usual finding. Congenital or developmental mandibular disorders are also possible causes for mouth opening limitation, although in a very small prevalence. Coronoid process hyperplasia (CPH) is an example of these cases, characterized by an excessive coronoid process growing, where mandibular movements become limited by the impaction of this structure on the posterior portion of the zygomatic bone. This condition is rare, painless, usually bilateral and progressive, affecting mainly men. Diagnosis of CPH is made based on clinical signs of mouth opening limitation together with imaging exams, especially panoramic radiography and computerized tomography (CT). Treatment is exclusively surgical. This paper presents a case of a male patient with bilateral coronoid process hyperplasia, initially diagnosed with bilateral disk displacement without reduction, and successfully treated with intraoral coronoidectomy. It is emphasized the importance of differential diagnosis for a correct diagnosis and, consequently, effective management strategy.  相似文献   
102.
Clinical and Experimental Nephrology - Ferric citrate hydrate (FC) is an oral iron-based phosphate binder that is used to treat hyperphosphatemia in patients with chronic kidney disease (CKD). This...  相似文献   
103.
Animal studies have demonstrated that experimentally induced vestibular ablation leads to a decrease in bone mineral density, through mechanisms mediated by the sympathetic nervous system. Loss of bone mineral density is a common and potentially morbid condition that occurs with aging, and we sought to investigate whether vestibular loss is associated with low bone mineral density in older adults. We evaluated this question in a cross-sectional analysis of data from the Baltimore Longitudinal Study of Aging (BLSA), a large, prospective cohort study managed by the National Institute on Aging (N = 389). Vestibular function was assessed with cervical vestibular evoked myogenic potentials (cVEMPs), a measure of saccular function. Bone mineral density was assessed using dual-energy X-ray absorptiometry (DEXA). In two-way t test analysis, we observed that individuals with reduced vestibular physiologic function had significantly lower bone mineral density. In adjusted multivariate linear regression analyses, we observed that older individuals with reduced vestibular physiologic function had significantly lower bone mineral density, specifically in weight-bearing hip and lower extremity bones. These results suggest that the vestibular system may contribute to bone homeostasis in older adults, notably of the weight-bearing hip bones at greatest risk of osteoporotic fracture. Further longitudinal analysis of vestibular function and bone mineral density in humans is needed to characterize this relationship and investigate the potential confounding effect of physical activity.  相似文献   
104.
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106.
Olfactory dysfunction and abnormalities of olfactory brain structures are found in patients with Parkinson's disease (PD), and a number of studies have reported that olfactory dysfunction is caused by abnormalities of the central olfactory systems. We previously analyzed electroencephalograms (EEGs) and respiration simultaneously in normal subjects while testing for detection and recognition of odors. We identified changes in respiration pattern in response to odor stimuli and found inspiratory phase-locked alpha oscillations (I-alpha). The genesis of I-alpha were identified in olfactory-related areas including the entorhinal cortex, hippocampus, amygdale and orbitofrontal cortex with an EEG dipole tracing method. In the present study, we used the same protocol in PD patients and compared results of PD with those of age-matched controls. All PD patients detected odor, but 5 out of 10 showed impaired odor recognition. Changes in breathing pattern associated with emotional changes during exposure to odor stimuli were not observed in PD patients. I-alpha waveforms were not observed; however, positive waves followed by negative waves were identified approximately 100ms after inspiration onset. Dipoles of this component were localized in the entorhinal cortex for odor detection in all patients and in the entorhinal cortex and middle temporal gyrus for PD patients who could discriminate odors. Odor recognition in PD could be subserved by a different neural circuit from that of normal subjects, done through the temporal association cortex as a subsystem for recognizing the odor; however, the system may not be associated with the odor-induced emotions.  相似文献   
107.
AIMS: Two different pathways of linoleic acid (LA) metabolism have opposite effects on the development of colonic cancer: a protumoral prostaglandin cascade metabolized by cyclooxygenase (COX)-2, and an antitumoral peroxisome proliferator-activated receptor (PPAR)-gamma ligands metabolized by 15-lipooxygenase (LOX)-1. The aim was to examine the switching of the two LA metabolic pathways in colonic adenomas and carcinomas. MATERIALS AND METHODS: The expression of 15LOX-1 mRNA and COX-2 protein was examined in 54 adenomas, 21 pTis carcinoma-in-adenoma lesions and 36 pT3/p Stage II carcinomas of the colon by in-situ hybridization and immunohistochemistry, respectively. Results: 15LOX-1 expression was found in 89% (48 of 54) of adenomas, 43% (nine of 21) of adenomas and 10% (two of 21) of carcinomas in carcinoma-in-adenoma lesions, but not in pT3 carcinomas (P < 0.0001). In contrast, COX-2 production was found in 11% (six of 54) of adenomas, 52% (11 of 21) of adenomas and 71% (15 of 21) of carcinomas in carcinoma-in-adenoma lesions, and 92% (33 of 36) of pT3 carcinomas (P < 0.0001). Concurrence of 15LOX-1 down-regulation and COX-2 up-regulation was found in 6% (three of 54) of adenomas, 33% (seven of 21) of adenomas and 71% (15 of 21) of carcinomas in carcinoma-in-adenoma lesions, and 92% (33 of 36) of pT3 carcinomas (P < 0.0001). CONCLUSIONS: These results suggest that switching of LA metabolism by reversal of the expression of 15LOX-1 and COX-2 is associated with acquisition of malignant potential in colonic neoplasia.  相似文献   
108.
Despite active investigation of copolymer-1 (Cop-1) for nearly 40 years the mechanisms underlying its neuroprotective properties remain contentious. Nonetheless, current dogma for Cop-1 neuroprotective activities in autoimmune and neurodegenerative diseases include bystander suppression of autoimmune T cells and attenuation of microglial responses. In this report, we demonstrate that Cop-1 interacts directly with primary human neurons and decreases neuronal cell death induced by staurosporine or oxidative stress. This neuroprotection is mediated through protein kinase Calpha and brain-derived neurotrophic factor. Dendritic cells (DC) uptake Cop-1, deliver it to the injury site, and release it in an active form. Interactions between Cop-1 and DC enhance DC blood brain barrier migration. In a rat model with optic nerve crush injury, Cop-1-primed DC induce T cell independent neuroprotection. These findings may facilitate the development of neuroprotective approaches using DC-mediated Cop-1 delivery to diseased nervous tissue.  相似文献   
109.

Purpose

Solute carrier SLC22A4 encodes the carnitine/organic cation transporter OCTN1 and is associated with inflammatory bowel disease, although little is known about how this gene is linked to pathogenesis. The aim of the present study was to identify endogenous substrates that are associated with gastrointestinal inflammation.

Methods

HEK293/OCTN1 and mock cells were incubated with colon extracts isolated from dextran sodium sulfate-induced colitis mice; the subsequent cell lysates were mixed with the amino group selective reagent 3-aminopyridyl-N-hydroxysuccinimidyl carbamate (APDS), to selectively label OCTN1 substrates. Precursor ion scanning against the fragment ion of APDS was then used to identify candidate OCTN1 substrates.

Results

Over 10,000 peaks were detected by precursor ion scanning; m/z 342 had a higher signal in HEK293/OCTN1 compared to mock cells. This peak was detected as a divalent ion that contained four APDS-derived fragments and was identified as spermine. Spermine concentration in peripheral blood mononuclear cells from octn1 gene knockout mice (octn1?/?) was significantly lower than in wild-type mice. Lipopolysaccharide-induced gene expression of inflammatory cytokines in peritoneal macrophages from octn1?/? mice was lower than in wild-type mice.

Conclusions

The combination metabolomics approach can provide a novel tool to identify endogenous substrates of OCTN1.
  相似文献   
110.
Globally, there have been increasing numbers of migrant women; these women are at an increased risk for depressive symptoms. The purpose of this study was to examine the associations among acculturation, acculturative stress and depressive symptoms in Vietnamese women who migrated to South Korea through marriages. We hypothesized that acculturative stress would serve as a mediator in the relationship between acculturation and depressive symptoms. Our findings from surveys with 217 Vietnamese immigrant women showed that the indirect effect of acculturation on depressive symptoms, mediated through acculturative stress [??.15 (.04)], was significant (bias corrected 95% confidence interval for the indirect effect?=???.25, ??.08). Low levels of acculturation increased acculturative stress, which in turn led to the elevated symptoms of depression. Our findings not only illuminate the adaptation processes of international, female migrants but also suggest avenues to protect and promote their mental well-being.  相似文献   
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