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101.
Superior orbital fissure syndrome is a symptomatologic complex, consisting of retroorbital pain, paralysis of extraocular muscles, impairment of first trigeminal branches and frequent involvement of the optic nerve. From a review of 130 published cases including two personal observations, it appears that the clinical subdivisions and the several eponymic differentiations of this syndrome are unjustified on the basis of etiologic, therapeutic and prognostic elements. Only the presence--or absence--of optic signs may allow to hold the clinically useful distinction between the often 'benign' superior orbital fissure syndrome without optic nerve involvement, and the orbital apex syndrome where orbital exploration may be recommended. This review concludes that repeated neurosurgical and neuroradiologic investigations--with the exceptions of carotid angiography and orbital phlebography--can be avoided in such cases.  相似文献   
102.
Fifty-three patients with relapsing-remitting multiple sclerosis who had monthly Gd (gadolinium) enhanced MRI (Magnetic Resonance Imaging) and clinical evaluation, were divided into two subgroups: 1) patients with a clinical relapse, treated with IVMP (intravenous methylprednisolone) and at least one enhancing lesion on MRI. 2) patients who did not have a clinical relapse but with at least one enhancing lesion on MRI. In group 1, we evaluated the number and volume of enhancing lesions on the scan before and three scans after IVMP therapy; in group 2, we considered the first scan with enhancing lesions and the subsequent three scans. The mean number and volume of enhancing lesions on the first scan was significantly higher in patients with clinical relapse compared to patients without clinical relapse. In group 1, we found a consistent reduction in the first scan following steroid treatment which returned to initial levels at the following scan. Both volumetric and numerical evaluation are appropiate MRI outcome measures in monitoring therapeutic trials.  相似文献   
103.
Transcranial Doppler in spontaneous attacks of migraine.   总被引:4,自引:0,他引:4  
BACKGROUND AND PURPOSE: Our aim in this study was to compare headache-free and spontaneous migraine measurements of blood flow velocity and the pulsatility index in the anterior cerebral artery, middle cerebral artery, and posterior cerebral artery. METHODS: Thirty-one patients (nine having experienced migraine with aura and 22 migraine without aura) were studied in headache-free periods and during spontaneous migraine attacks with transcranial Doppler ultrasonography. RESULTS: During attacks of migraine with aura, blood flow velocities (particularly the diastolic velocity [p = 0.05]) were reduced while the pulsatility index increased (p = 0.05), whereas a generalized increase in diastolic velocity (p less than 0.02) and a decrease in the pulsatility index (p = 0.05) were observed during attacks of migraine without aura. Significant variations of blood pressure and heart rate were never found. CONCLUSIONS: These findings are consistent with constriction of resistance vessels in migraine with aura and dilatation of the vessels in migraine without aura. This disparity could be due to a difference between the two migraine types or could be related to the fact that in this study the time interval between headache onset and transcranial Doppler was shorter in the migraine-with-aura group. The latter explanation would apply if, in fact, both types of migraine evolve from hypoperfusion to hyperperfusion during their time course, although perhaps with a difference in intensity.  相似文献   
104.
OBJECTIVE: To evaluate whether recombinant human interferon-beta-1a significantly affects disease activity as measured by a reduction in the number and volume of Gd enhancing lesions on monthly MRI. The study also evaluated the effect on six-monthly T2 weighted abnormality and relapse frequency. METHODS: After a baseline scan and a six month pretreatment period, 68 patients were randomly assigned to receive either 3 MIU or 9 MIU of interferon-beta-1a by subcutaneous injection three times a week for six months. All patients were examined by Gd enhanced MRI every month in both pretreatment and treatment periods. The evaluation of Gd enhancing lesions was performed blind at the end of the study. RESULTS: The mean number of Gd enhancing lesions was higher during the pretreatment period than during treatment. This difference was statistically significant for the two different dose subgroups (3.5 v 1.8, P < 0.001 for the 3 MIU group and 2.4 v 0.9, P < 0.001 for the 9 MIU group, corresponding to a reduction of 49% and 64% respectively). The mean volume of Gd enhancing lesions also significantly decreased by 61% (3 MIU group) and 73% (9 MIU group). These reductions were evident only after the first month of treatment. The six-monthly rate of new lesions as seen in T2 weighted images showed a similar trend of reduction with treatment (65% and 70% respectively). Lesion volume on T2 scans significantly increased during the pretreatment period whereas it remained almost stable during the treatment period in both groups. Clinical relapse rate was significantly reduced by treatment (53% for the 3 MIU group, P < 0.001; 69% for the 9 MIU group, P < 0.001). CONCLUSION: Interferon-beta-1a seemed effective in reducing disease activity in relapsing-remitting multiple sclerosis at both the doses used.  相似文献   
105.
Quantitative magnetic resonance analysis in vascular dementia   总被引:13,自引:0,他引:13  
The potential role of magnetic resonance imaging (MRI) in differentiating between specific causes of cognitive decline in patients with vascular dementia (VD) has not yet been fully established. We therefore decided to assess the supratentorial cerebral contents in 24 patients with a diagnosis of probable VD and in 24 normal subjects, matched for age and education level, using MRI volumetric parameters obtained by means of a quantitative method. The volumes of subarachnoid and ventricular spaces, cerebral tissue, and hyperintense areas on T2-weighted images were calculated. In order to reduce interindividual variability caused by differences in intracranial size, each absolute measurement was normalized to the relative size of the intracranial volume. In addition, we calculated the ratio between the areas of the corpus callosum (CC) and supratentorial brain at the same level on the T1-weighted image midsagittal plane. The MRI data were correlated with the deterioration of cognitive functions. Patients with VD showed significantly lower cerebral tissue volume and CC area, and higher ventricular space volume than normal subjects. Furthermore, the total volume of the T2 signal alterations was higher in VD patients than in normal subjects. In VD patients, this volume was found to be proportional to the increase in the volume of the ventricular space. On the other hand, no correlation was found between the volume of the T2 signal alterations and the area of the CC. The degree of global cognitive dysfunction and the score of each neuropsychological test did not show any correlation with the MRI data. Our results suggest that ventricular enlargement in VD patients is correlated with the increase in volume of the T2 signal abnormalities, but that the degree of global cognitive dysfunction is not influenced by the volume of these T2 signal abnormalities. Furthermore, the CC atrophy does not influence the score of any neuropsychological test or the degree of global cognitive dysfunction. Received: 22 Februar 1996 Received in revised form: 14 October 1996 Accepted: 30 December 1996  相似文献   
106.
We applied the technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) split-dose method in order to evaluate the feasibility of assessing cerebral blood flow (CBF) changes with single photon emission tomography (SPET) during a motor activation task. Eleven normal subjects were studied using the Tomomatic 564 (Medimatic, DK). Five subjects were studied twice at rest and 6 subjects at rest and during a motor task performance (finger opposition movements). A total of 28 mCi of 99mTc-HMPAO was injected in 2 doses with a 1:3 ratio. The first scan was obtained after injection of 7 mCi at rest in all subjects. The second scan was obtained a few minutes later, after injection of the remaining dose (21 mCi), under similar resting conditions or during a motor task performance. The mean brain uptake was proportional to the amount of tracer injected and to the acquisition time for both the first scan (5263 +/- 1266 counts x mCi x min) and the second (5034.4 +/- 966 counts x mCi x min). The grey/white matter ratio was 1.67 +/- 0.019 and 1.67 +/- 0.097 for the two scans, respectively. A three-way analysis of variance (ANOVA) for repeated measure showed no significant effects of side, slice and region of interest (ROI) on the CBF in the 5 subjects studied twice at rest, and the mean regional CBF change was -0.2% +/- 5%.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
107.
108.
Summary A consecutive series of 327 patients (188 males, 139 females; mean age 68.4, SEM 1.33) were hospitalized within 12 h of the onset of their first-ever hemispheric infarct. Three groups of patients were identified: diabetics (n = 70), non-diabetic hyperglycaemics (n = 93) and normoglycaemics (n = 164). Case-fatality ratios at 30 days after stroke were 38.6%, 22.6% and 9.2% (P < 0.001) respectively, whereas the causes of death and functional outcome of survivors were not significantly different between the groups. Mean admission serum glucose levels (SGLs) of deceased, impaired/unchanged and improved patients within each one of the three groups, were also not significantly different as opposed to their mean Canadian Neurological Scale (CNS) scores at entry (P < 0.01). Among patients with less severe initial neurological deficit (i.e., CNS score 7.0), 82.6% of non-diabetic hyperglycaemic subjects fared well, in comparison with 56.5% of diabetic and 70.1% of normoglycaemic individuals. The size of the infarcted areas at the second CT correlated with mean CNS scores (P < 0.01) but not with mean SGLs on admission. The site of the ischaemic areas did not correlate with mean SGLs at entry. Therefore the influence of initial SGLs on the clinical course of the present series of patients is questionable or, alternatively, varied probably according to the pattern of residual cerebral blood flow after arterial occlusion.  相似文献   
109.
Mendelian susceptibility to mycobacterial diseases confers predisposition to clinical disease caused by weakly virulent mycobacterial species in otherwise healthy individuals. Since 1996, disease-causing mutations have been found in five autosomal genes (IFNGR1, IFNGR2, STAT1, IL12B, IL12BR1) and one X-linked gene (NEMO). These genes display a high degree of allelic heterogeneity, defining at least 13 disorders. Although genetically different, these conditions are immunologically related, as all result in impaired IL-12/23-IFN-γ-mediated immunity. These disorders were initially thought to be rare, but have now been diagnosed in over 220 patients from over 43 countries worldwide. We review here the molecular, cellular, and clinical features of patients with inborn errors of the IL-12/23-IFN-γ circuit.  相似文献   
110.
T cell clones derived from cerebrospinal fluid (CSF) of patients with multiple sclerosis (MS) were analysed for their ability to produce interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha), interleukin-2 (IL-2) and interleukin-4 (IL-4). The CSF-T clones were compared for their ability to produce cytokines with autologous peripheral T clones and with liver-infiltrating T cell clones from patients with chronic active hepatitis. IL-4 production was also compared with that by peripheral T clones derived from atopic patients. All the CSF-T clones (both CD4+ and CD8+) produced large amounts of IFN-gamma and particularly of TNF-alpha. These cytokines were synthesized in significantly larger amounts by CSF T clones than by reference clones. Moreover, they were capable of secreting IL-2, but not IL-4. We conclude that the CSF-CD4+ T clones could constitute a subset with functional properties similar to those of T helper 1 (Th1)inflammatory cells of the mouse; and that the large amounts of TNF produced by CSF T cell clones strongly suggest a significant role for this cytokine in MS immunopathogenesis.  相似文献   
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