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991.
992.
Estrogen deficiency and its effect on the jaw bones   总被引:1,自引:0,他引:1  
Estrogen deficiency-induced postmenopausal osteoporosis has become a worldwide problem, inducing low bone mass and microarchitectural deterioration of the bone scaffolding in the vertebrae and long bones. With the prevalence of such osteoporosis on the increase, the influence of this estrogen deficiency on the jaw bones has drawn the attention of researchers and clinicians in the field of dentistry. The aim of this article is therefore to review the microstructural changes occurring after ovariectomy in the jaw bones of animal subjects. Induced estrogen deficiency clearly led to structural changes in the jaw bones and alveolar bone of animal subjects (rats and monkeys). Severe bone loss in the rat alveolar bone was principally caused by high bone resorptive activity. This activity accelerated greatly immediately after ovariectomy, and was then followed by more moderate resorptive activity, which continued over an extended period. Additionally, occlusal hypofunction further greatly accelerated the fragility of the alveolar bone structure in ovariectomized rats. Microstructural damage also seen in the alveolar bone of ovariectomized monkeys was found to be directly connected to their systemic osteoporosis. Recent investigations of the relationship in humans between systemic osteoporosis and jaw bone loss have also suggested that a connection may exist between these two. However, more research is required to confirm this connection in humans as well.  相似文献   
993.
No strategies for the diagnosis and treatment of biliary tract carcinoma have been clearly described. We developed flowcharts for the diagnosis and treatment of biliary tract carcinoma on the basis of the best clinical evidence. Risk factors for bile duct carcinoma are a dilated type of pancreaticobiliary maljunction (PBM) and primary sclerosing cholangitis. A nondilated type of PBM is a risk factor for gallbladder carcinoma. Symptoms that may indicate biliary tract carcinoma are jaundice and pain in the upper right area of the abdomen. The first step of diagnosis is to carry out blood biochemistry tests and ultrasonography (US) of the abdomen. The second step of diagnosis is to find the local extension of the carcinoma by means of computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance cholangiopancreatography (MRCP), percutaneous transhepatic cholangiography (PTC), and endoscopic retrograde cholangiopancreatography (ERCP). Because resection is the only way to completely cure biliary tract carcinoma, the indications for resection are determined first. In patients with resectable disease, the indications for biliary drainage or portal vein embolization (PVE) are checked. In those with nonresectable disease, biliary stenting, chemotherapy, radiotherapy, and/or best supportive care is selected.  相似文献   
994.
Hepatocellular carcinoma (HCC) frequently metastasizes to the adrenal glands. The surgical strategy for HCC associated with bilateral adrenal gland metastasis is complicated because of the possibility of both postoperative hepatic failure and adrenal insufficiency. We herein report a patient with HCC with synchronous bilateral adrenal gland metastasis that was treated successfully with a two-stage operation. A 58-year-old man with HCC (12 cm in diameter) in the right lobe of the liver and bilateral adrenal gland tumors (right, 4 cm in diameter; left, 5 cm in diameter) was admitted to our hospital. Extended right hemihepatectomy and right adrenalectomy were performed simultaneously. The postoperative course was uneventful. Three months after this operation, left adrenalectomy was performed via a retroperitoneal approach. Hydrocortisone supplement was given, and the postoperative course was again uneventful. No recurrence was observed during the 10-month follow-up period. Two-stage surgery is a safe treatment option for giant HCC with synchronous bilateral adrenal gland metastasis.  相似文献   
995.
Natural immunological tolerance can be induced in certain types of allogeneic liver transplantation in rats. To screen for genes associated with the induction of tolerance, suppression subtractive hybridization was performed in the rat liver transplantation model between a DA donor and PVG recipient combination where spontaneous immunological tolerance is known to occur without any immunosuppressive treatment. As a result, 112 genes were cloned from a DA liver graft that survived for 20 days in the fully allogeneic PVG recipient. After confirmation of the expression intensity using an in-house manufactured DNA array with cDNAs from the DA graft, 36 genes were classified in the highly expressed group and 26 moderately expressed group. In the first group, there were 8 immunoglobulin-related genes and 6 MHC class II-related genes, suggesting the existence of an underlying rejection response. Among those genes, an antiapoptotic gene in the p38 MAP kinase pathway, heme oxygenase gene (HO-1), and a ras cascade gene, IQ motif containing GTPase activating protein 1 (Iqgapl), retained biological significance. The results suggested that the molecular response to a liver graft tends to be antiapoptotic and to terminate the rejection response. Unfortunately, there was no gene identified that qualified as a putative immunosuppressive protein, liver suppressor factor-1 (LSF-1). The panel of genes identified in the present work will be a useful panel of candidate genes to investigate the induction of spontaneous tolerance.  相似文献   
996.
Background It is known that vitamin D has many functions besides involvement in calcium metabolism. It has recently been recognized that vitamin D deficiency is associated with mortality, especially in cardiovascular disease (CVD). Vitamin D deficiency is common in end-stage renal disease, but develops from the early stage of chronic kidney disease (CKD). So we investigated whether the serum level of the activated form of vitamin D (1,25-dihydroxyvitamin D) affected mortality in patients with CKD stages 3 and 4. Methods Between January 1, 1995, and June 30, 2006 we measured serum 1,25-dihydroxyvitamin D In 226 patients with CKD stages 3 and 4 and classified the results into two groups depending on whether the level was below (group I) or above (group II) 20 pg/ml. We ended the follow-up period on December 31, 2006. We compared all-cause and cardiovascular mortality between the two groups. We also examined predictors of mortality by using Cox proportional regression analysis. Results Two-hundred and twenty-six patients (67 men and 159 women, mean age 67.0) were registered in this study, and groups 1 and 2 comprised 84 and 142 patients, respectively. During the follow-up period 43 patients died. CVD was the major cause of death, followed by infectious disease. The Kaplan–Meier survival curve revealed that all-cause mortality was significantly higher in group I, but a significant difference between CVD mortality in the two groups was not demonstrated. By Cox proportional regression analysis, group I was related to all-cause mortality, but this was not proved to be an independent predictor. Conclusion The results suggested that serum level of 1,25-dihydroxyvitamin D was associated with all-cause mortality in patients with CKD stages 3 and 4.  相似文献   
997.
We evaluated the usefulness of intravenous lidocaine therapy for managing of status epilepticus (SE) during childhood in a retrospective multi-institutional study. Questionnaires were sent to 28 hospitals concerning patients admitted for SE who were managed with lidocaine, assessing patient characteristics, treatment protocols and efficacy. In 279 treated patients, 261 SE occurrences at ages between 1 month and 15 years were analyzed. SE was classified as showing continuous, clustered, or frequently repeated seizures. Considering efficacy and side effects in combination, the usefulness of lidocaine was classified into six categories: extremely useful, useful, slightly useful, not useful, associated with deterioration, or unevaluated. In 148 SE cases (56.7%), lidocaine was rated as useful or extremely useful. Multivariate analysis indicated lidocaine was to be useful in SE with clustered and frequently repeated seizures, and SE attributable to certain acute illnesses, such as convulsions with mild gastroenteritis. Efficacy was poor when SE caused by central nervous system (CNS) infectious disease. Standard doses (approximately 2mg/kg as a bolus, 2mg/kg/h as maintenance) produced better outcomes than lower or higher doses. Poor responders to the initial bolus injection of lidocaine were less likely to respond to subsequent continuous infusion than good initial responders. We recommend lidocaine for use in SE with clustered or frequently repeated seizures, and in SE associated with benign infantile convulsion and convulsions with mild gastroenteritis. Lidocaine should be initiated with a bolus of 2mg/kg. If SE is arrested by the bolus, continuous maintenance infusion should follow; treatment should proceed to different measures when SE shows a poor response to the initial bolus of lidocaine.  相似文献   
998.
Male monozygotic twins with genetically determined severe myoclonic epilepsy in infancy are described. Although seizure onset, clinical seizure symptomatology, and motor and mental development were almost identical until age 38 months, their clinical courses then became discordant. The emergence of myoclonus was delayed by 12 months in twin 1 compared with twin 2. Regression in language development, which is a common feature of severe myoclonic epilepsy in infancy, was obvious in twin 2 after the emergence of myoclonus, whereas twin 1 did not demonstrate any regression. The clinical-course discordance between twins was attributable to bacterial meningitis, which twin 1 developed at age 35 months. Bacterial meningitis may have affected the clinical course of severe myoclonic epilepsy in infancy in twin 1, resulting in delayed onset of myoclonus and more favorable language development in twin 1 than in twin 2, who did not experience bacterial meningitis.  相似文献   
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