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51.
The clinical, echocardiographic and angiographic aspects of a four-month-old boy with double-outlet left ventricle, atrioventricular discordance, L-malposition of the great arteries, ventricular septal defect and pulmonary stenosis are described. Additionally, in this patient, the right arcus aorta and the ligament of ductus arteriosus caused anterior compression of the trachea. The anterior position of the morphological left ventricle is the most interesting feature.  相似文献   
52.
Idiopathic hypertrophic cranial pachymeningitis (IHCP) consists of meningeal thickening due to chronic inflammation for which no cause such as infection, specific granulomatous disease, or malignancy is demonstrable. We present a case of IHCP with perifocal brain edema suggesting mass lesion with its magnetic resonance imaging (MRI) and pathologic findings. A 36-year-old woman was admitted to our hospital in August 2001 with a complaint of motor weakness in her left leg for 1 month. Magnetic resonance imaging with gadolinium revealed enhancement of the thickened dura mater and perifocal edema in the right frontoparietal region suggesting a mass lesion. Histological examination of the biopsy specimen revealed a dense fibrous cellular tissue. There was no obvious inflammatory infiltrate but in some areas between fibrous bundles one or two lymphocytes were detected. According to our knowledge, our patient is the second report in the literature of IHCP with focal edema causing a mass effect.  相似文献   
53.
BACKGROUND: The integrity of working memory in attention-deficit/hyperactivity disorder (ADHD) was tested within the framework of Baddeley's model. METHODS-1: Buffers and rehearsal mechanisms were assessed by presenting children with or without ADHD (ages 8 to 15) with 1-7 target letters and a probe after 2-10 s. They decided if the probe was the same (verbal task) or in the same location (spatial task) as any of the targets. RESULTS-1: There was no interaction between group and delay or memory load in either task. METHODS-2: The central executive was assessed on a dual task. RESULTS-2: Although children with ADHD did not differ from controls in simple response time (RT) or in digits recalled, they showed greater decrements in RT when performing the 2 tasks concurrently. CONCLUSIONS: Findings suggest that children with ADHD (1) do not have generalized impairments in working memory, (2) rehearse verbal and spatial information in the same manner as healthy children, (3) may have an impairment in the central executive component of working memory, which controls ability to divide attention between two tasks.  相似文献   
54.
Possible clinical relevance of Nm23 expression, angiogenesis and proliferative activity were evaluated as prognostic parameters in childhood embryonal rhabdomyosarcoma (RMS). Specimens of 25 RMS cases were studied for Nm23 antigen immunohistochemically. Vascular surface density (VSD) and number of vessels per stroma (NVES) calculated by stereologic methods on labeling sections with CD34 antibody. For evaluation of proliferative activity of tumors, mitotic figures and Ki67 positive cells were investigated. All findings were searched statistically. Five patients were stage 1 (20%), two were stage 2 (8%), 15 were stage 3 (60%) and three were stage 4 (12%). The mean event free survival (EFS) was 20.8 and the mean overall survival (OS) was 25.9 months. Sixteen patients (64%) were alive and without disease. The percentage of Nm23 positivity was 52%. Log rank analysis showed Nm23 as a predictor for survival (p=0.0313). In Pearson correlation analysis, there was statistical significance between OS and presence of Nm23 expression (p=0.044). VSD was also positively related with EFS (p=0.040). Despite the present parameters in use, there is a need for new prognostic markers, especially to predict the outcome of patients. These findings suggested that Nm23 expression and VSD might be useful for follow-up in RMS.  相似文献   
55.
In this study, we determined the plasma TGF-beta1 levels in healthy and thrombocytopenic and nonthrombocytopenic neonates who had perinatal risk factors and examined the association between plasma TGF-beta1 levels and platelet counts in these newborns to investigate the role of TGF-beta1 in the pathogenesis of neonatal thrombocytopenia. Three groups were defined in this prospective study: group 1, thrombocytopenic neonates (n=22) who had perinatal risk factors; group 2, nonthrombocytopenic neonates who had similar perinatal risk factors for thrombocytopenia (n=20); group 3, healthy and nonthrombocytopenic neonates without any risk factors (n=20). Plasma TGF-beta1 levels were measured with ELISA. Plasma TGF-beta1 levels of the thrombocytopenic neonates were significantly lower than those of healthy nonthrombocytopenic neonates but did not differ significantly from nonthrombocytopenic neonates who had similar perinatal risk factors for thrombocytopenia. There was a significant positive correlation between plasma TGF-beta1 levels and platelet counts. Further studies are needed to determine the cause of low plasma TGF-beta1 levels in thrombocytopenic neonates and to investigate the role of plasma TGF-beta1 levels in the pathogenesis of neonatal thrombocytopenia.  相似文献   
56.
Turkey is located in a geographic area of the world where thalassemia syndromes and abnormal hemoglobins are common. In this study we aimed to evaluate the thalassemia syndromes and abnormal hemoglobins in patients from the Aegean region of Turkey. Among the patients admitted to our Pediatric Hematology or Hematology Clinic between January 1997-September 1999, hemoglobin electrophoresis of 3,228 cases investigated for anemia was done using high performance liquid chromatography. Beta thalassemia trait was diagnosed in 21.1%, beta thalassemia major in 0.2%, S-beta thalassemia in 0.37%, Hb D in 0.37%, Hb S trait in 0.32%, Hb E in 0.18%, Hb O-Arab in 0.12%, Hb G-Copenhagen in 0.09%, Hb D-Iran in 0.06%, Hb Lepore in 0.06%, Hb Hasharon in 0.03%. Our results demonstrate that people in the Aegean region of Turkey have a wide spectrum of thalassemia syndromes and abnormal hemoglobins.  相似文献   
57.
We retrospectively assessed the clinical course and outcome of left-sided endocarditis in pediatric patients to find out the prognostic significance of the presence and size of echocardiographically detected vegetations. Among the children admitted to our institution with endocarditis between January 1987 and October 1999, 16 patients (mean age 9.03 +/- 4.95 years) who met the Duke criteria for the diagnosis of infective endocarditis (IE) were included in this study. Rheumatic valvular disease was the most frequent underlying heart disease (10 patients: 62.5%). Five patients were operated at a mean of 13.9 months before endocarditis, and all had residual defects. Vegetation was detected in 11 cases (69%). Ten patients had major complications (within 2 weeks in 6 patients). Three patients developed congestive heart failure (CHF), six had intracranial and one had lower extremity emboli. Among them four were operated because of complications (CHF: 3 cases, intracranial emboli: 1 case). All the operated cases are doing well. The association between intracranial embolic events and echocardiographically detected vegetations was determined by calculating specificity (40%), sensitivity (100%), positive predictive value (50%), and negative predictive value (100%). No intracranial embolism occurred in patients without vegetations. All vegetations were < or = 6 mm in patients with systemic embolism. There were four deaths, three of which were because of intracranial embolism. This study suggests that intracranial emboli have a major risk of mortality in left-sided endocarditis. The larger size of the vegetation is not a predictor of complications; furthermore, the absence of vegetations predicts that the patient is safe from embolic events. Therefore all patients with left-sided IE should be considered for earlier surgical intervention.  相似文献   
58.
INTRODUCTION: We have investigated the volume of nerve fibers in the rat urinary bladder following systematic exposure to cold-restraint stress and capsaicin treatment. MATERIALS AND METHODS: Adult Wistar albino rats were either exposed to cold-restraint stress (vehicle group) or treated with capsaicin before exposure to cold-restraint stress (capsaicin group). In the control group, animals were neither exposed to cold-restraint stress nor given capsaicin. From each group, samples of bladder were prepared for morphological investigation and stereological evaluation of the volume of nerve fibers. RESULTS: Stress exposure was associated with urothelial degeneration, a higher incidence and degranulation of mast cell profiles in the mucosa, and an increased volume of nerve fibers in the muscular layer of the bladder wall. Capsaicin treatment prevented the stress-induced degenerative changes. In the capsaicin group, the volume of nerve fibers in the muscular layer was also significantly smaller than that in the stress group. CONCLUSIONS: Exposure of adult rats to capsaicin prevented the stress-induced degeneration of the bladder and changed the volume of capsaicin-sensitive fibers in muscular layer. We conclude that capsaicin and related compounds may be useful in treating stress-induced bladder problems.  相似文献   
59.
PURPOSE: New contact lens materials with high oxygen permeability are said to be convenient for the extended-wear (EW) schedule. We evaluated the short-term effect of EW soft contact lens usage on ocular surface and central corneal thickness. PATIENTS AND METHODS: Fifty-two eyes of 26 patients were included in the study. Sixteen of the patients used the high oxygen-permeable lenses for a 30-day extended-wear schedule (group I). Ten patients used the lenses on a daily wear basis (DW, group II). All patients were evaluated for visual acuity and central corneal thickness by corneal and conjunctival biomicroscopy, Schirmer and tear break-up time (BUT) tests. Impression cytology was performed in the superior/temporal, inferior/nasal quadrants of the conjunctiva, 1 mm from the limbus, with cellulose acetate filter paper. The specimens were graded under light microscopy according to Nelson's classification. RESULTS: Three patients in the EW group were excluded from the study as they discontinued lens usage due to slight discomfort and hyperemia. Biomicroscopic findings and tear function tests indicated no increased pathological results. Central corneal thickness decreased from 554 +/- 9.55 to 546 +/- 9.30 microm (mean +/- SEM) in the EW group (p = 0.002), whereas no significant change occurred in the DW group. Cytological evaluation of the EW group showed an 88% increase in metaplasia (p = 0.007), especially close to the limbal areas and in the superior quadrants; this ratio was 30% in the DW group. Snake-like chromatin changes were found to be increased, from 4 to 6 patients, in the EW group while it remained the same in the DW group (p > 0.05). Individual comparisons of the initial and final pathological conditions of the ocular surfaces in the two groups showed that there was an increase in pathology in the EW group while there was no significant difference in the DW group. CONCLUSIONS: On a 30-day extended-wear basis with high oxygen-permeable lenses, the possible development and increase of conjunctival cytologic changes secondary to mechanical trauma is one of the main remaining problems. Conjunctival and related immunologic pathologies should not be overlooked when prescribing an extended-wear lens schedule.  相似文献   
60.
Monitoring of Vibrio species by blue crabs (Callinectes sapidus) was carried out during the winter period in a selected area of the Belek, Antalya Gulf. Eighty-three blue crabs were examined for Vibrio species. V. alginolyticus (30.1%), V. fluvialis (10.8%), V. damsela (9.6%), V. harveyi (3.6%), V. metschnikovii (3.6%) and V. vulnificus (2.4%) were isolated. V. vulnificus was the highest concentration (5 x 10(8) Vibrio ml(-1)) although it was only 2.4% isolated from blue crabs. The strains of different vibrio species were highly susceptible to doxycycline, tetracycline and ciprofloxacin.  相似文献   
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