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Genomewide scans of inbred strains of mice have linked the genes encoding the hepatocanalicular cholesterol transporter ABCG5/G8 to gallstone formation. Five nonsynonymous coding single-nucleotide polymorphisms (SNPs) in the orthologous human genes are associated with differences in serum cholesterol and plant sterol levels. We now tested these ABCG5/G8 SNPs for linkage and association with gallstone susceptibility in humans. Prospectively, we collected data from 178 white individuals with gallbladder stones or history of cholecystectomy in 84 families and from 70 stone-free controls, as confirmed by abdominal ultrasound. We performed nonparametric linkage (NPL) analysis of affected sib pairs (ASPs) and association tests of cases and controls. In ASPs, gallstones were strongly linked to the D19H variant of the ABCG8 gene (NPL score = 7.1; P = 4.6 x 10(-13)). The risk of gallstones in carriers of the 19H allele was significantly increased in randomly selected cases from the ASP cohort compared to the stone-free controls (OR = 3.018; P = 0.017). Consistent with the mouse model, heterozygosity for the lithogenic ABCG8 allele was associated with gallstones in humans; 21.4% of gallstone patients carried the heterozygous D19H genotype, compared with 8.6% of controls (OR = 2.954; P = 0.026). CONCLUSION: The linkage and association studies identified the cholesterol transporter ABCG5/G8 as a genetic determinant of gallstone formation, or LITH gene, in humans. The function of this transporter and the results of the genetic study taken together indicate that in gallstone-susceptible carriers of the ABCG8 19H allele, cholesterol cholelithiasis is secondary to increased hepatobiliary cholesterol secretion.  相似文献   
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Fine-needle aspiration (FNA) biopsy of the salivary gland is a sensitive and specific diagnostic tool. However, diagnostic problems are sometimes encountered in interpreting some cases, not only in differentiating benign from malignant cases but also in the specific classification of these neoplasms. We report a case of a pleomorphic adenoma with predominant plasmocytoid myoepithelial cells arising in minor salivary glands from the hard palate in a 78-year-old patient, which was falsely diagnosed as a carcinoma on liquid-based cytology (ThinPrep (TP)). The differential diagnosis of salivary gland tumors with predominant myoepithelial cells on FNA biopsy is discussed.  相似文献   
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The aim of the neurosurgical treatment in neuro-oncology is multiple: diagnostic (obtaining of a precise histopathological diagnosis to improve the treatment and the further prognosis), symptomatic (the improvement of the neurological clinical features by decreasing intracranial pressure) and therapeutic (to obtain a cytoreductive treatment, by complete or partial exeresis of the tumoural mass). To establish a precise histopathological diagnosis, during the intervention and latter, on the paraffin sections, the neuropathologist must examine the neurosurgical drawings knowing the history of the illness, the clinical and radiological aspects of the case in study, which complains a good cooperation between neurosurgeon and neuropathologist. To initiate the procedures of histopathological processing of various neurosurgical drawings, the neuropathologist must understand very well the surgical procedure. This is the reason of this study: to present different neurosurgical technics; the choose of one of these essentially depends on the location and size of the cerebral tumour, on neuroradiological characteristics and presumptive histopathological diagnosis and on the neurological status, the age and the general condition of the patient.  相似文献   
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Echocardiography commonly represents the diagnostic clue in neonatal heart failure (HF). Congenital heart diseases are the most frequent causes of HF in this age group. Arterio-venous malformations are the most common noncardiac causes of HF. Normal cardiac structural findings on echocardiography require further investigations in order to exclude other causes of HF. We present three male patients admitted in the interval 2003-2007 with neonatal HF, systolic murmur, cardiomegaly, normal cardiac structure on echocardiography and intracranial bruit. All three cases were diagnosed with vein of Galen aneurysmal malformation (VGAM) by head ultrasound. According to age and malformation type, different presentation patterns were noticed: early neonatal intractable HF mimicking aortic coarctation, postnatal HF stabilized by drug treatment, and chronic HF in a VGAM with tendency to spontaneous regression. Both head ultrasound and cranial auscultation are mandatory in newborns or infants with no cardiac primary cause of HF.  相似文献   
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In the present study are depicted valuable observations for practitioners, obtained from an in vitro study which aims to evaluate the compressive strength of occlusal veneers fabricated from 3 type of restorative materials, before and after 1 month of acidic artificial saliva exposure (pH = 2.939). In this context, 90 extracted human molars were prepared to receive computer-aided design/computer-aided manufacturing (CAD/CAM) occlusal veneers. The restorative materials considered in this study were: Cerasmart; Straumann Nice and Tetric CAD. The occlusal veneers were designed, milled and cemented with an adhesive dual-cure resin cement. From all the extracted human molars, only sixty specimens were immersed in acidic artificial saliva, for 1 month, at 37 °C ± 1 °C and part of this specimens were also thermo-cycled, between 5 and 55 °C ± 2 °C, before compressive strength test. The results showed a lower compressive strength for both the samples exposed to acidic artificial saliva as well as for the samples exposed to acidic artificial saliva and thermo-cycled. Scanning electron microscopy (SEM) showed that after compressive strength, all the specimens non-exposed to acidic artificial saliva, present extensive cracks formation at the surface of the restorations, and after exposure to acidic artificial saliva for 1 month, the surface damage was characterized by longitudinal and profound fractures of the restoration, as well as the fracture of the tooth structure. Between CAD/CAM materials tested, nanoceramic resin shows more favorable fracture patterns, both before and after acidic artificial saliva exposure.

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