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1.
The use of directional coronary atherectomy (DCA) in current practice has been limited. The SilverHawk System is a newly developed plaque excision device that aims to overcome the drawbacks of prior DCA platforms. The device was evaluated in a porcine coronary model and in a series of patients. Procedural variables along with outcomes were reviewed. Quantitative angiography (QCA) was performed and excised tissue fragments were weighed and examined histologically. In porcine cases, pretreatment MLD increased from 0.51 +/- 0.26 to 2.36 +/- 0.59 mm postdebulking and 19.9 +/- 7.6 mg of tissue was retrieved. In human cases, pretreatment MLD increased from 0.8 +/- 0.4 to 2.2 +/- 0.5 mm postdebulking and 15.2 +/- 7.8 mg of tissue was retrieved without complications. These data show that the SilverHawk System may offer significant utility in treating a wide variety of complex coronary lesions.  相似文献   
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Dopa-decarboxylase activity was high at 2-3 weeks of age, low at 5-6 weeks, and very low in adult rats; protease activity increased with age. Trypsin-like proteases, which decrease dopa-decarboxylase activity, were detected in the gland and were inhibited by a protease inhibitor, leupeptin. High concentrations (20 mg/ml) of leupeptin increased dopa-decarboxylase activity in the glands of adult rats to the level found at 5-6 weeks of age. The low activity of dopa decarboxylase in adult gland may be due in part to endogenous proteases.  相似文献   
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ObjectivesThe Alberta Stroke Program Early Computed Tomography Score (ASPECTS) is a promising tool for the evaluation of stroke expansion to determine suitability for reperfusion therapy. The aim of this study was to validate deep learning-based ASPECTS calculation software that utilizes a three-dimensional fully convolutional network-based brain hemisphere comparison algorithm (3D-BHCA).Materials and MethodsWe retrospectively collected head non-contrast computed tomography (CT) data from 71 patients with acute ischemic stroke and 80 non-stroke patients. The results for ASPECTS on CT assessed by 5 stroke neurologists and by the 3D-BHCA model were compared with the ground truth by means of region-based and score-based analyses.ResultsIn total, 151 patients and 3020 (151 × 20) ASPECTS regions were investigated. Median time from onset to CT was 195 min in the stroke patients. In region-based analysis, the sensitivity (0.80), specificity (0.97), and accuracy (0.96) of the 3D-BHCA model were superior to those of stroke neurologists. The sensitivity (0.98), specificity (0.92), and accuracy (0.97) of dichotomized ASPECTS > 5 analysis and the intraclass correlation coefficient (0.90) in total score-based analysis of the 3D-BHCA model were superior to those of stroke neurologists overall. When patients with stroke were stratified by onset-to-CT time, the 3D-BHCA model exhibited the highest performance to calculate ASPECTS, even in the earliest time period.ConclusionsThe automated ASPECTS calculation software we developed using a deep learning-based algorithm was superior or equal to stroke neurologists in performing ASPECTS calculation in patients with acute stroke and non-stroke patients.  相似文献   
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We report a case of an infant with unique and unreported combinations of brain anomalies. The patient showed distinctive facial findings, severe delay in psychomotor development, cranial nerve palsy and seizures. Brain magnetic resonance imaging performed at 5 days of age revealed complex brain malformations, including heterotopia around the mesial wall of lateral ventricles, dysmorphic cingulate gyrus, and enlarged midbrain tectum. The patient unexpectedly died at 13 months of age. Postmortem pathological findings included a polymicrogyric cingulate cortex, periventricular nodular heterotopia, basal ganglia and thalamic anomalies, and dysmorphic midbrain tectum. Potential candidate genes showed no abnormalities by traditional PCR‐based sequencing. Whole‐exome sequencing confirmed the presence of novel gene variants for filamin B (FLNB), guanylate binding protein family member 6, and chromosome X open reading frame 59, which adapt to the autosomal recessive mode or X‐linked recessive mode. Although immunohistochemical analysis confirmed the expression of FLNB protein in the vessel walls and white matter in autopsied specimens, there may be functional relevance of the compound heterozygous FLNB variants during brain development.  相似文献   
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This study aimed to evaluate postoperative long‐term liver restoration and splenic enlargement and their clinical significance in living donor liver transplantation. One hundred and sixteen donors who had donated livers more than 5 years previously accepted the invitation to participate in this study. The liver restoration rate and the splenic enlargement rate were calculated as the rate with respect to the original volume. The mean liver restoration rate was 0.99 ± 0.12 and older age was associated with a higher incidence for liver restoration rate <0.95 (P = .005), whereas type of donor operation was not. The donors with liver restoration rate <0.95 showed lower serum albumin levels than those with liver restoration rate ≥0.95. The mean splenic enlargement rate was 1.10 ± 0.16. Right lobe donors demonstrated higher splenic enlargement rate (1.14 ± 0.18) than left lobe/lateral segment donors (1.06 ± 0.13). In the donors with splenic enlargement rate ≥1.10, platelet count was not fully restored to the preoperative level. In conclusion, older age increases the risk for incomplete postoperative liver restoration, which may be associated with a decrease in albumin more than 5 years after donation. Right lobe donation poses a risk of splenic enlargement, which is associated with incomplete restoration of platelet count.  相似文献   
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Repetitive intermittent hypoxia-ischemia and brain damage in neonatal rats   总被引:1,自引:0,他引:1  
OBJECTIVE: To know the effect of brief-repetitive intermittent hypoxia-ischemia on the development of perinatal brain damage. STUDY DESIGN: Seven-day-old Wistar rats underwent ligation of the unilateral common carotid artery. The animals were allocated to three groups (n=12 in each group) and exposed to 8% oxygen as follows: group A: continuous exposure for 180 min; group B: continuous exposure for 90 min; and group C: 10 min of exposure repeated at 10-min intervals over a period of 180 min (total exposure time, 90 min). Seventy-two hours after exposure to hypoxia, the cerebral cortex was examined to assess the degree of neuronal necrosis and brain damage was classified into four grades of severity, 0-3. To evaluate the extent of brain damage, we used immunohistochemical staining with TIB-128 antibody, which reacts to MAC-1 antigen specific to microglia, and observed the glial reaction in the cerebral cortex, hippocampus, thalamus, and striatum. RESULTS: All the brain damage observed in groups A-C occurred on the side where the ligation was performed. The most severe damage was found in group A animals, of which seven showed significant neuronal necrosis, having a grade 2 or more advanced lesion. In group B, neuronal necrosis was modest, with only one animal having a grade 2 lesion. In group C, a significant neuronal necrosis was found in six animals despite having the same period of hypoxic exposure as those in group B. MAC-1 positive cells appeared in the cerebral cortex of histologically damaged animals and extended to the hippocampus, thalamus, and striatum in severely damaged animals from groups A, B, and C. CONCLUSION: Examination of the neonatal rat model suggested that repetitive and intermittent, rather than continuous hypoxia-ischemia, causes pronounced damage in the immature brain.  相似文献   
9.
The increase in parotid rather than pancreatic-type amylase activity in the submandibular and sublingual glands of rats caused by administration of pilocarpine was abolished or diminished when pilocarpine was injected into rats which had been parotidectomized, sympathectomized by superior cervical ganglionectomy or pretreated with reserpine. These results suggest that the increases in amylase activity in the submandibular and sublingual glands by pilocarpine are not due to increase in enzyme synthesis, but to uptake of enzyme released into the blood in large quantities from the parotid gland and that the release from the parotid gland by pilocarpine is primarily mediated by sympathetic nerves.  相似文献   
10.
This study examined the effect of housing density on the longevity-extending and disease-delaying actions of calorie restriction (CR). Singly or multiply housed (four per cage) mice were either fed ad libitum (AL) or were on CR beginning at 2 months. All CR mice were fed 40% less food than were multiply housed AL mice. CR increased median longevity by 19%, and housing density had no effect on this increase. CR also reduced neoplastic lesions in both housing groups, but lymphoma, the most common neoplasm, was reduced more in singly than in multiply housed mice. Singly housed AL mice ate 40% more food than did multiply housed AL mice, but weighed the same and lived as long as multiply housed AL mice. These results indicate that CR can extend life span as effectively in multiply as in singly housed mice, even though housing density can differentially affect the cancer-reducing effect of CR.  相似文献   
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