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1.
We aimed to demonstrate the effect of angle and laminectomy on paired pedicle screws to determine whether a 90 degrees screw angle is optimal as has been previously suggested. According to the angle between right and left screws, 28 calf vertebrae were divided into three groups and instrumented as follows: Group I: 60 degrees screw angle; Group II: 90 degrees angle; Group III: 60 degrees angle with laminectomy. The screws were connected using rods and cross-fixators and tested to peak pullout force. Triangulated pedicle screws provided 76.5% more pullout strength than single screws. Most of the specimens failed through loss of convergence angle (toggling of screws on the rods) and subsequent uni- or bilateral screw pullout. Mean+/-SD peak loads were: Group I: 2071+/-622 N; Group II: 1753+/-497 N; Group III: 2186+/-587 N. The differences were not significant (p>0.05). 90 degrees triangulation was not associated with a superior pullout performance versus conventional 60 degrees triangulation, suggesting that achieving additional triangulation angle is not necessary to obtain increased pullout strength. Laminectomy did not alter the effect of triangulation on fixation strength.  相似文献   
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BACKGROUND AND AIM: Subclinical hepatic encephalopathy (HE) in cirrhotic patients is usually characterized by memory impairment and psychomotor slowing. Our aim was to investigate memory status in cirrhotic patients with and without clinically overt HE. MATERIAL AND METHODS: Thirty-two cirrhotic patients (10 female and 22 male) aged 49 +/- 17 years and 20 healthy subjects (six female and 14 male) aged 46 +/- 12 years were included in the study. Memory status was defined by Wechsler Memory Scale, verbal memory process and complex memory process tests. RESULTS: Grade-1 HE was detected in 7 (22%) patients with cirrhosis. We detected 36 to 92% decrement in various memory tests in cirrhotic patients without HE as compared to healthy subjects. The scores for all psychometric testing results were significantly lower in cirrhotic patients without HE as compared to healthy subjects. We detected 42.9 to 100% decrement in various memory tests in cirrhotic patients with HE than cirrhotic patients without HE. However, there was no statistical significant difference between cirrhotic patients with and without HE. There was no statistical significant difference in cirrhotic patients with Child-Pugh A, B, and C. CONCLUSION: In conclusion, memory status was influenced in which patients with cirrhosis yet has a normal mental and neurological status to routine clinical examination (subclinical HE). Occasionally, decreased memory performance may adversely affect the satisfaction and lifestyle of these patients. Therefore, subclinical HE is an important social problem.  相似文献   
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ObjectiveThis study aimed to describe the clinical, endoscopic, and histologic characteristics, as well as the response to conventional treatment of pediatric patients with the classical form of eosinophilic esophagitis (EoE).MethodsStudy of clinical, laboratory, endoscopic, and histologic data and response to conventional treatment of 43 previously followed pediatric patients with the classical form of EoE.ResultsA total of 43 patients diagnosed with EoE were included in the study, of which 37 were males (86%), with a mean age of 8.4 years. The most common symptoms were: nausea, vomiting, and abdominal pain (100%) in children younger than 7 years, and loss of appetite (60%), heartburn (52%), and food impaction (48%) in children older than 7 years and adolescents. Regarding the endoscopic findings, 12 (28%) patients had whitish plaques on the esophageal lining, 8 (18.5%) had longitudinal grooves, 2 (4.5%) had concentric rings, 3 (7%) had longitudinal grooves and whitish plaques, and the remaining 18 (42%) had esophageal mucosa with normal appearance. Despite the initial favorable response, 76.7% of patients required more than one course of corticosteroid therapy (systemic or aerosol) and diet (exclusion or elimination of food or elementary allergens). Persistence of eosinophil infiltration was found in some patients despite favorable clinical response.ConclusionsThe classic form of EoE typically shows different symptoms according age range. A significant number of patients required more than one treatment cycle to show clinical remission. Endoscopic and histologic improvement was observed; however, eosinophilic infiltration persisted in some patients.  相似文献   
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Torsion of the fallopian tube accompanying hydrosalpinx is a rare occurrence in the pediatric population. This report describes a 13 year old sexually inactive girl with isolated tubal torsion due to hydrosalpinx. The girl had lower left abdominal pain for two days. The physical examination revealed left lower quadrant tenderness with a firm round anterior mass on rectal examination. Abdominal ultrasound showed left tubal enlargement with free pelvic peritoneal fluid. Magnetic Resonance Imaging (MRI) showed engorgement and dilatation of the left fallopian tube without contrast enhancement suspicious of tubal torsion. At operation, torsion of the left tube on its longitudinal axis was observed, and a salpingectomy was performed.  相似文献   
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AIMS: On the basis of the evidence from autopsy studies, it is accepted that compensatory enlargement (remodelling) of coronary arteries during progression of atherosclerosis diminishes once atheroma burden (cross-sectional area stenosis) reaches approximately 40%. Our aim was to evaluate whether atheroma burden is a limiting factor for coronary arterial remodelling using in vivo serial intravascular ultrasound (IVUS). METHODS AND RESULTS: From the cohort of the Reversal of Atherosclerosis with Aggressive Lipid Lowering (REVERSAL) trial, we identified 210 focal coronary lesions at baseline IVUS. Of these, 128 lesions that had an increase in atheroma area at the 18-month follow-up IVUS were included in the analysis. Lesions were matched at baseline and follow-up. The increase in external elastic membrane (EEM) area for each mm(2) increase in atheroma area was not significantly different in lesions with <40 and >or=40% atheroma burden at baseline (1.62 vs. 1.28 mm(2), P=0.30). There were no correlations between atheroma burden at baseline and change in EEM (r=0.02, P=0.86) or change in lumen (r=0.04, P=0.64) areas. CONCLUSION: Assessment of coronary arterial remodelling by serial IVUS revealed that compensatory remodelling is not limited by atheroma burden. Atheroma burden is not a determinant of arterial enlargement during the progression of atherosclerosis.  相似文献   
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Current evidence strongly suggests that aberrant activation of the nuclear factor kappa B (NF-kB) signaling cascade is connected to carcinogenesis. The matrix metalloproteinases (MMP) which are also the key agents for tumor metastasis may be potent candidates for tumor diagnosis in clinics. In this in vitro study, we hypothesized that metformin with an effective dose can inhibit tumor cell proliferation and metastasis by modulating the expressions of MMP-2 and -9 and interfering with NF-kB signaling in primary breast cancer cells (PBCCs). 300 000 cells per ml were obtained from biopsies of breast tumors from five human donors. The cell viability and proliferation were tested. Immunocytochemistry was performed for MMP-2, MMP-9, and NF-kB, and enzyme-linked immunosorbent assay for NF-kB activity, quantitative real-time PCR for RELA/p65, IkBα, MMP-2, and MMP-9. Three different doses of metformin (5, 10, and 25 mM) (Met) reduced the viability and proliferation of PBCCs in a dose-dependent manner, maximum inhibition was observed at 25 mM Met. The expression of RELA/p65 was not affected by 25 mM Met. Nuclear immunoreactivity and activity of NF-kB reduced while cytoplasmic NF-kB (p65) elevated by 25 mM Met compared to non-treatment (P < 0.05). The expression and immunoreactivity of MMP-9 but not MMP-2 were decreased by 25 mM Met treatment, compared with the non-treatment (P < 0.05). Metformin may have an essential antitumor role in the invasion and metastasis pathways of PBCCs by downregulating the MMP-9 expression blocking both the activity and nuclear translocation of NF-kB.  相似文献   
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In order to gain insight into the possiblemechanisms involved in gallstone formation incolectomized ulcerative colitis patients, we studiedgallbladder motility by means of ultrasonography inthree groups of subjects: controls (N = 40) and ulcerativecolitis patients without (N = 30) and with (N = 20)colectomy. Impaired gallbladder emptying after a liquidfatty meal stimulus was observed in ulcerative colitis patients with colectomy compared with thoseobtained in ulcerative colitis patients withoutcolectomy and controls (P = 0.001). The maximumpercentage of gallbladder emptying also, wassignificantly lower (59.8%) than those seen in ulcerative colitispatients without colectomy (74.5%) and controls (77.8%)(P = 0.001). Diminished gallbladder emptying withensuing stasis might be a contributory factor to the increased prevalence of gallstones incolectomized patients.  相似文献   
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