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11.
Two distinct hereditary defects, vitamin D-dependent rickets type I (VDDR I) and type II (VDDR II), have been recognized in vitamin D metabolism. VDDR I is suggested to be a deficiency of the renal 25-hydroxyvitamin D (25(OH)D)-1α-hydroxylase. Muscle weakness and rickets are the prominent clinical findings. A normal physiologic dose of 1α-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 is sufficient to maintain remission of rickets in this disorder. VDDR II consists of a spectrum of intracellular vitamin D receptor (VDR) defects and is characterized by the early onset of severe rickets and associated alopecia. This can be attributed to mutations in the VDR gene. Massive doses of vitamin D analogs and calcium supplementation is usually required for the treatment; however, the response to therapy is sometimes variable.  相似文献   
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Cholestatic hepatocellular carcinoma, which grows into the bile duct and causes obstructive jaundice, is rare and difficult to diagnose. A case is presented in which cholestatic hepatocellular carcinoma was detected by deposit of Lipiodol. This is also the first case that was successfully treated by endoscopic retrograde biliary drainage and transcatheter arterial embolization.  相似文献   
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Altered intrahepatic pathway of para-umbilical vein in portal hypertension   总被引:2,自引:0,他引:2  
The object of this study was to determine the frequency and characteristics of altered paraumbilical vein in the hepatic parenchyma, developed from portal hypertension, using computed tomography (CT). Two hundred and ninety-two patients who presented with portal hypertension from 1986 to 1996 were studied retrospectively. The pathway of the dilated para-umbilical vein was demonstrated by contrast-enhanced CT. Thirty-one (11%) patients had a dilated para-umbilical vein arising from the left portal vein into the falciform ligament. In 24 (77%) of these patients, the para-umbilical vein followed the expected route, passing through the fissure of ligamentum teres hepatis. The remaining seven patients (23%) displayed the unusual pathway, with the vein arising from the left branch of the portal vein and passing into the hepatic parenchyma. In these seven patients, four had one collateral vein, and three patients had two collateral veins in the liver parenchyma. The dilated para-umbilical vein frequently passes through the hepatic parenchyma in patients with portal hypertension.  相似文献   
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Azoospermia is the most frequent cause of male infertility. After excluding the obvious urological reasons and the effect of Klinefelter's syndrome, azoospermia may be caused by an abnormality in the crucial gene(s) expressed during male germ cell differentiation. Recently, two candidate genes for azoospermia have been cloned from the azoospermic factor (AZF) locus on the Y chromosome long arm (Yq). One is YRRM (Y chromosome RNA recognition motif) gene, and the other is DAZ (deletion in azoospermia) gene. Both genes encode RNA binding protein and their expression is restricted to the testis. Therefore they are good candidates for AZF, although their function remains unclear. Here, the genes on the Y chromosome possibly involved in spermatogenesis and the role of the Y chromosome in evolution are discussed.  相似文献   
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N-Acetylglucosaminyltransferase III (GnT III) catalyses the addition of N-acetylglucosamine through a β 1–4 linkage to the mannose of the trimannosyl core, resulting in conversion of the concanavalin A (Con A)-reactive glycan into a non-reactive state. In this study, we measured GnT III activity to evaluate its diagnostic efficacy and its therapeutic effect on hepatocellular carcinoma (HCC). Concanavalin A-non-reactive fraction of serum transferrin (Tf) was also determined since the sugar chains of Tf are one of the possible candidates for the product of GnT III. Serum samples (159) were used from patients with HCC (89), liver cirrhosis (30), chronic hepatitis (19), alpha-fetoprotein (AFP) producing gastric carcinoma metastatic to the liver (five) and healthy controls (16). N-Acetyl-glucosaminyltransferase III activity was determined by high performance liquid chromatography. The reactivity of serum Tf to Con A was also analysed in 21 paired HCC samples before and after treatment by crossed immuno-affinoelectrophoresis. N-Acetylglucosaminyltransferase III activity from the HCC group (153 ± 72 pmol/mL/h) was significantly higher than that from liver cirrhosis (99 ± 67 pmol/mL per h), chronic hepatitis (84 ± 39pmol/mL per h) and the normal controls (62 ± 16pmol/mL per h). N-Acetylgiucosaminyltransferase III activity of 21 patients with HCC was significantly reduced after treatment such as transcatheter arterial chemoembolization and/or percutaneous ethanol infection therapy, (123 ± 77 to 100 ± 60pmol/mL per h). Commensurate decreases of AFP and des-γ-carboxy prothrombin with GnT III activity were also observed after treatment. The Con A-non-reactive fraction (n= 21; 6.4 ± 2.3%) in patients with HCC after treatment was significantly lower than before (8.2 ± 2.4%). The present study suggests that GnT III activity is a possible and in the diagnosis and evaluation of HCC, especially when other tumour markers are negative.  相似文献   
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