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91.
BACKGROUND: It is known that chromium is an inhaled carcinogen and an important risk factor in the development of lung carcinoma. METHODS: The authors used a microscopic X-ray fluorescence analyzer with transmitted X-ray mapping imaging (Horiba, Kyoto, Japan) to measure the accumulation of chromium in 10 resected lung tissue specimens and 90 biopsy specimens from chromate workers. RESULTS: The maximum chromium accumulation (mean +/- standard deviation) in 10 resected lung tissue specimens was 197 +/- 238 counts per second (cps)/mili ampere (mA) (range, 4-649 cps/mA). Chromium accumulation was scattered in six tissue specimens and diffuse in one specimen. Chromium accumulation in the proximal bronchi was less than in the bronchioles or subpleural regions of the lung. Chromium accumulation was detectable in 63 (70%) of 90 biopsy specimens, and the mean accumulation was 6.5 +/- 9.2 cps/mA (range, 0-46.5 cps/mA). Chromium detected in bronchial tissue specimens was deposited in the bronchial stroma but not in the epithelium. The maximum chromium accumulations in dysplasic (n = 3), squamous metaplastic (n = 10), and normal bronchial epithelia (n = 9) in chromate workers and in normal bronchial epithelia (n = 3) in non-chromate workers were 20.2 +/- 5.4, 18.3 +/- 12.2, 13.2 +/- 13.4, and 3.0 +/- 1.8 cps/mA, respectively. The amount of chromium accumulation significantly increased according to the progression of malignant change of the bronchial epithelium (P = 0.003). CONCLUSIONS: Previous studies found that lung carcinoma with chromate exposure exhibited a variety of genetic abnormalities. Considering genetic aberrations and chromium accumulation in these premalignant lesions is useful for elucidating the process of carcinogenesis in chromium-induced lung carcinoma.  相似文献   
92.
Immunolocalization of 14-3-3 protein isoforms in relation to Pick bodies in Pick body disease (PBD) brains was investigated. Weakly granular immunoreactivity of 14-3-3 proteins was found in neurons in control subjects and in Pick body disease brains. In addition to this granular immunoreactivity, many Pick bodies were immunopositive for 14-3-3 proteins as confirmed with double-immunofluorescence with an anti-PHF tau (AT8) and anti-14-3-3 that recognizes all its isoforms (common). When probed with isoform-specific antibodies, Pick bodies were positive for beta, gamma, epsilon, eta, tau, and zeta isoform and exhibited immunostaining pattern similar to that observed with the anti-14-3-3 proteins (common). In addition, immunoreactivity of sigma isoform, so far considered to be exclusively extraneuronal, was unexpectedly found in Pick bodies, normal hippocampal neurons and brain homogenate from age-matched controls. Although localization of 14-3-3 proteins in Pick bodies suggests their involvement in Pick body formation, their role may be variable dependent on the isoforms differently expressed in different area in the brain.  相似文献   
93.
Rotational vertebral artery occlusion is a rare cause of ischemic stroke in the vertebrobasilar arteries. While computed tomography angiography (CTA) is less invasive for the diagnosis of rational vertebral artery occlusion than digital subtraction angiography and more useful for elucidating the correlation between vertebrobasilar arteries and the surrounding structure, carotid ultrasound is noninvasive and more beneficial for the real-time evaluation of the hemodynamic change with neck rotation compared to CTA. Here, we reported 2 cases of rotational vertebral artery occlusion in patients aged 81 and 38 years and proposed a novel technique for its diagnosis using ultrasound-guided CTA. We suggest that the combination of ultrasound and CTA is useful for diagnosing rotational vertebral artery occlusion, which would compensate for the disadvantages of CTA alone.  相似文献   
94.
95.
Histological and molecular changes were examined to investigate the effects of long-term administration of glucosamine (GlcN) and chondroitin sulfate (CS) in a model of spontaneous osteoarthritis (OA) in Hartley guinea pigs. Three groups of female 3-week-old Hartley guinea pigs received GlcN, CS, and neither agent, respectively. Five animals in each group were sacrificed at 8, 12, and 18 months of age. At 8 months of age, Hartley guinea pigs had severe degeneration of knee joint cartilage, chondrocyte apoptosis, marked reduction of tissue total RNA, decreases of aggrecan and collagen type 2 mRNAs, and increases in MMP-3 and MMP-8 mRNAs. Long-term administration of GlcN and CS reduced cartilage degeneration at 8 months of age. The marked loss of total RNA and the increase in MMP-3 mRNA were also inhibited by GlcN and CS. Thus, long-term oral administration of GlcN or CS inhibits OA progression, maintains total RNA and down-regulates MMP-3 mRNA in a spontaneous OA model in Hartley guinea pigs.  相似文献   
96.
A case of meningioangiomatosis not associated with neurofibromatosis 2 in a 24-year-old man is reported. Abundant neurofibrillary tangles and threads, shown by immunohistochemistry and ultrastructural analysis to be similar to those seen in Alzheimer’s disease, were found in the residual neuropil. Another lesion consisting of argyrophilic globular inclusion bodies with radial fibrils was found at the periphery. Single and double immunostaining with a panel of antibodies showed similarities between these inclusions and Pick bodies. Received: 18 August 1997 / Revised, accepted: 10 December 1997  相似文献   
97.
Nosological placement of l'hérédo-ataxie cérébelleuse de Pierre Marie (HAC) has never been established even after several autopsy cases from the original Haudebourg family had been reported. To reappraise the clinical and pathological features of HAC in the current framework of hereditary ataxias, we screened the autopsy records of la Salpêtrière hospital and identified a patient with a diagnosis of HAC who underwent an autopsy in 1943. Clinical features included heredity compatible with autosomal dominant inheritance, spasticity, increased tendon reflexes, mask-like face, visual impairment, nuclear ophthalmoparesis, and exophthalmos in addition to progressive ataxia. Pathological lesions included the spinal cord (spinocerebellar tracts, anterolateral fascicles, and posterior column), cerebellar dentate nucleus, pontine nucleus, pallidum, motor neurons including the oculomotor nucleus, and substantia nigra. The cerebellar cortex and inferior olives were preserved. These clinical and pathological features, similar to those described in patients from the Haudebourg family, a core prototype of HAC, are indistinguishable from those of Machado-Joseph disease. It would then be possible to conclude that some of the patients historically considered to have HAC would today be classified as having Machado-Joseph disease.  相似文献   
98.
From pre- and postoperative urodynamic examinations of congenital neurogenic bladder caused by tethered cord syndrome including tight filum terminate, the results of intraspinal surgery on tethered cord syndrome are reported herein. As a result, urodynamic and electrophysiologic examinations are considered as excellent methods, which are safe and give objective findings, for diagnosis and prolonged observation of not only tethered cord syndrome but also congenital neurogenic bladder.  相似文献   
99.
We report here an early autopsy case of a 60-year-old woman clinically diagnosed as having frontal lobe dementia without other neurological deficits. Postmortem examination revealed mild spongiosis in layers II and III of the frontal cortex, together with depletion of melanin-containing neurons in the substantia nigra. In addition to ubiquitin-positive neurites, ubiquitin-positive, tau-negative inclusions, which were previously considered to be a hallmark for motor neuron disease with or without dementia, were identified in neurons of the hippocampal dentate gyrus and of the temporal cortex. Although the patient lacked lower motor symptoms, the presence of Bunina bodies identified in the hypoglossal nuclei further supported the relationship of this case to motor neuron disease. Bunina bodies might be present in some cases of frontal lobe dementia. The presence or absence of Bunina bodies should be scrutinized even in cases without motor symptoms. In this case, creatine kinase of skeletal muscle origin was elevated, which might also be a potential indicator that suggests subclinical involvement of lower motor neurons.  相似文献   
100.
BACKGROUND/AIMS: To address the molecular mechanism for enhanced antiviral efficacy associated with a frequent dosing of interferon (IFN)-beta. METHODS: Serum hepatitis C viral (HCV) dynamics, double-stranded RNA-activated protein kinase (PKR) mRNA and MxA mRNA levels in peripheral blood mononuclear cells (PBMC) were analyzed serially in 140 patients who were randomly assigned to a twice daily (3 MU bid) or once daily (6 MU qd) administration group. RESULTS: In twice daily group, the rate of HCV decline during the second phase was 2-fold greater than in the once daily group (P=0.04). Peak PKR and MxA gene expression levels in the first phase (observed 4 h after a single administration) were 2-fold higher in the once daily group. However, the expression in the second phase was maintained at a significantly higher level in the twice daily group. Initial and peak expression levels were related to initial viral load. Basal expressions in PBMC were significantly correlated with those in the liver tissue (PKR, r=0.81; MxA, r=0.75, respectively, P<0.0001). CONCLUSIONS: Our data suggest that elimination of HCV-infected cells is enhanced by twice daily dosing of IFN-beta, and that this enhanced effect is associated with a higher intracellular expression of PKR and MxA during the second phase.  相似文献   
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