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PURPOSENonalcoholic fatty liver disease (NAFLD) can progress to liver cirrhosis and is predicted to become the most frequent indication for liver transplantation in the near future. Noninvasive assessment of NAFLD is important for diagnosis and patient management. This study aims to prospectively determine the liver stiffness and T1 and T2 values in patients with NAFLD and to compare the diagnostic performance of magnetic resonance elastography (MRE) and mapping techniques in relation to the proton density fat fraction (PDFF).METHODSEighty-three patients with NAFLD and 26 participants with normal livers were imaged with a 1.5 T scanner. PDFF measurements obtained from the multiecho Dixon technique were used to quantify the liver fat. MRE, native T1 mapping (modified Look-Locker inversion recovery [MOLLI] schemes 5(3)3, 3(3)3(3)5, and 3(2)3(2)5 and the B1-corrected variable flip angle [VFA] method), and T2 mapping values were correlated with PDFF. The diagnostic performance of MRE and the mapping techniques were analyzed and compared.RESULTST1 values measured with the MOLLI schemes and the B1-corrected VFA (p < 0.001), and the stiffness values from MRE (p = 0.047) were significantly higher in the NAFLD group. No significant difference was found between the groups in terms of T2 values (p = 0.127). In differentiation of the NAFLD and control groups, the B1-corrected VFA technique had slightly higher accuracy and area under the curve (AUC) than the MOLLI schemes. In the NAFLD group, there was a good correlation between the PDFF, MOLLI 3(3)3(3)5 and 3(2)3(2)5, and VFA T1 measurements (r=0.732; r=0.735; r=0.716, p < 0.001, respectively).CONCLUSIONLiver T1 mapping techniques have the potential to distinguish steatotic from nonsteatotic livers, and T1 values seem to have a strong correlation with the liver fat content.

Nonalcoholic fatty liver disease (NAFLD) is one of the most common causes of chronic liver disease, with an estimated worldwide prevalence of around 25% (1). It may range from simple steatosis, which is considered a benign condition, to nonalcoholic steatohepatitis (NASH), which can progress to fibrosis, cirrhosis, liver failure, and hepatocellular carcinoma. NAFLD is also known to be associated with metabolic syndrome, which is a risk factor for cardiovascular disease and type II diabetes mellitus (24).The gold standard method for diagnosing NAFLD and distinguishing its different patterns is a liver biopsy which has considerable limitations, including sampling errors, its invasive nature and associated complication risks, small sample size, and inter- and intraobserver variability (5, 6). These drawbacks constrain its utility for clinical monitoring and make it unsuitable as a screening method. Therefore, there is an urgent clinical need for an accurate noninvasive approach in the assessment of NAFLD. Accordingly, both the European Association for the Study of the Liver and the American Association for the Study of Liver Disease propose magnetic resonance imaging (MRI) as a noninvasive diagnostic tool for NAFLD (7, 8). Proton density fat fraction (PDFF)-based MRI and magnetic resonance spectroscopy (MRS) techniques are considered the most accurate noninvasive methods for the quantification of liver fat (912). The PDFF is accepted as a standardized biomarker of hepatic steatosis. Studies suggest that this biomarker is equivalent to the hepatic “signal fat fraction” (FF) after correcting all the confounding factors (13). However, PDFF measurement is not suitable for the assessment of any inflammation or fibrosis in NAFLD (13). On the other hand, recent studies have shown that other quantitative MRI techniques such as magnetic resonance elastography (MRE) and T1–T2 mapping can be useful in detecting hepatic inflammatory and fibrotic changes (14, 1521). Thus, the application of a multiparametric MRI protocol might be helpful in liver tissue characterization and thereby in the risk stratification and therapeutic management of patients with NAFLD.In this prospective study, we aimed to determine liver stiffness and T1 and T2 values in patients with NAFLD and nonsteatotic subjects and compare the diagnostic performance of MRE and mapping techniques in relation to the FF.  相似文献   
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Aromatic L-amino acid decarboxylase (AADC), a vitamin B6-requiring enzyme that converts L-dopa to dopamine and 5-hydroxytryptophan to serotonin. Deficiency of this enzyme results in developmental delay, muscular hypotonia, dystonia, involuntary movements, autonomic dysfunction, and oculogyric crises. We now report a 2-year-old Turkish boy with AADC deficiency confirmed by greatly reduced AADC activity in the plasma and by genetic studies. Mutation analysis revealed a homozygous mutation c.208C > T (p. His70Tyr) in exon 3 of the AADC gene which has not been described to date.  相似文献   
5.

Objective

Thalamic abnormalities have been reported in people with pervasive developmental disorders (PDD) including Asperger''s Disorder (ASP). The aim of the present study was to compare the volume and volume fraction of the thalamus and the metabolite concentrations in children and adolescents with ASP using the magnetic resonance imaging and proton magnetic resonance spectroscopy. Additionally, the relationships between thalamic abnormalities and clinical features were examined.

Methods

Volume and volume fractional and metabolic measurements of bilateral thalamus were collected from 15 boys with ASP with a total IQ over 70 (age range 7-18 years, mean age 11.6±3.79 years), and 15 healthy controls matching age, sex and IQ. The thalamic volumes, hemisphere volumes and total brain volumes (TBV) were estimated using the stereological methods on magnetic resonance images. Chemical metabolites of thalamus were evaluated by 1H spectroscopy.

Results

No differences in thalamic volumes, volume fractions and metabolites were observed between the groups. There were significant correlation between thalamic volume and total brain volume in both groups. The ASP group showed a significant left-minus-right thalamus difference as well as a significantly greater laterality index. In addition, a significant correlation between the laterality index and Autism Behavior Checklist language scores was observed.

Conclusion

Findings from this investigation point to a significant increase in laterality of the thalamus and a relationship with language problems in individuals with ASP. Our findings suggest that thalamic abnormalities may be related to mild language problems observed in ASP.  相似文献   
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Haloperidol is commonly used in the treatment of psychiatric disorders. Data from animal experiments indicate haloperidol is not teratogenic, but is embryotoxic in high doses. For the first time, we report a neonate with transient nephrogenic diabetes insipidus (DI) caused by fetal exposure to haloperidol. The magnitude of risk associated with the use of haloperidol during pregnancy appears to be small, but nephrogenic DI secondary to haloperidol is a serious condition with the risk of hypernatremic dehydration. Haloperidol can have adverse effects on the fetus and newborn infant, that’s why one should prevent the use of haloperidol during pregnancy and lactation.  相似文献   
7.
The present study evaluated the properties of nails, frequency of ingrown nails in patients with type 2 diabetes mellitus (DM), risk factors for developing ingrown nails, and effect of diabetic polyneuropathy and vasculopathy on the development and outcome of ingrown nails. Our 6-month epidemiologic prospective study included 300 patients with type 2 DM attending a DM outpatient clinic for routine examinations. The general characteristics and foot changes of the study population were investigated. Diabetic polyneuropathy and vasculopathy were evaluated using a biothesiometer, monofilament tests, and arterial Doppler ultrasonography. The frequency of ingrown nails was 13.6%. Multivariate analysis with logistic regression showed that body mass index (odds ratio [OR] 1.077, 95% confidence interval [CI] 1.007 to 1.15; p?=?.03), previous trauma (OR 2.828, 95% CI 1.017 to 7,867, p?=?.042), a weak dorsalis pedis pulse (OR 2.72, 95% CI 1.17 to 6.30, p?=?.02), trimming type (OR 2.3, 95 CI 1.06 to 4.98), p?=?.35), onychogryphosis (OR 9.036, 95% CI 2.34 to 34.87, p?=?.001), and subungual hyperkeratosis (OR 4.3, 95% CI 1.99 to 9.3, p?=?.001) were predictive variables for ingrown nails in our population. The incidence of onychomycosis was significantly greater in patients with ingrown nails (p?=?.032) than in patients without ingrown nails. The nail curvature ratio was greater in the patients with ingrown nails than in the group with normal nails. Arterial Doppler ultrasound examinations showed peripheral arterial disease in 19 patients (46.9%) with ingrown nails. The prevalence of ingrown nails was greater in the patients with DM than in the healthy population. Our results indicate that nail type, nail morphology, and diabetic vasculopathy affect the formation and evolution of ingrown nails.  相似文献   
8.
The aim of this study was to describe clinical features of PBD comorbidity in children with ASD. Forty children with ASD and PBD aged 6–18 years, and 40 age- and sex-matched ASD subjects with no affective episodes were included in the study. Autism Behavior CheckList, Abberant Behavior CheckList, and Young Mania Rating Scale-Parent Version were completed. This study shows that PBD comorbidity in children with ASD involves a highly episodic course, with manic episodes, subsyndromal symptoms and interepisodic periods commonly being described in the manic symptom profile of these children. These findings need to be repeated with large samples, together with controlled studies concerning therapeutic interventions directed toward PBD comorbidity in children with ASD.  相似文献   
9.
Purpose: This study investigated the antioxidant effects of whortleberry against cisplatin-induced nephrotoxicity in rats.

Material and methods: This study included 48 female Sprague–Dawley rats weighing 263.68?±?8.29?g. The rats were divided into the following six groups, with eight rats in each group: control, ethanol control, whortleberry control, cisplatin control, 16?mg/kg cisplatin +100?mg/kg whortleberry, and 16?mg/kg cisplatin +200?mg/kg whortleberry groups. Biochemical analysis was performed by measuring total oxidant status and total antioxidant status, histopathological analysis was performed by calculating proximal and distal tubule areas (μm2), and immunohistochemical analysis was performed by determining anti-Caspase-3 immunostaining. Differences among the groups were examined using one-way analysis of variance, and p?Results: Cisplatin treatment decreased the total antioxidant status and increased the total oxidant status and Caspase-3 level. Moreover, it resulted in the dilatation, vacuolization and loss of tubular epithelial cells; and glomerular degeneration and edema in the kidney tissues (p?p?Conclusions: Our results indicate that the antioxidant effects of the whortleberry decrease cisplatin-associated nephrotoxicity.  相似文献   
10.
The purpose of this study was to investigate the efficacy of recombinant human granulocyte/macrophage colony-stimulating factor (rHuGM-CSF) on the wound healing of colonic anastomosis in rats. In total, 40 male Wistar rats were taken into this study. The control group (n = 20) received subcutaneous saline injection. The experiment group (n  相似文献   
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