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81.
82.
Choriocarcinoma, a malignant tumor of usually placental origin, in divided into two groups; the gestational and non-gestational types, the latter being rate. Non-gestational choriocarcinoma occurs in the lung, mediastinum, kidney, stomach, and small intestine, but rarely appears in the large intestine. We treated a 29-year-old woman with choriocarcinoma of the rectum with adenocarcinoma. Despite the rarity of the condition and the obscurity of the histogenesis, reports of similar cases and the occurrence of the tumors in the digestive tract suggest that the condition constitutes a clinical entity of a digestive tumor.  相似文献   
83.
Acinar cell carcinoma of the pancreas with elevated serum alpha-fetoprotein   总被引:2,自引:0,他引:2  
A case of acinar cell carcinoma of the pancreas with elevated serum alpha-fetoprotein (AFP) is presented. The diagnosis was reached using histopathological techniques. AFP was positive in the tumor specimen, immunohistochemically. Serum AFP had fallen temporarily after surgery and chemotherapy. The patient survived 6.5 months after the onset of symptoms.  相似文献   
84.
Our aim was to find out whether the quality of bone around the inferior alveolar nerve is correlated with neurosensory disturbance to the nerve after sagittal split ramus osteotomy (SSRO) in patients with mandibular prognathism. Computed tomograms (CT) were taken of 35 patients with mandibular prognathism and 35 without. To assess the density of bone around the inferior alveolar nerve, the width of the buccal cortical bone in the mandibular second molar regions was measured on CT. The Hounsfield units (HU) in the same regions were also measured. The number of HU in the mandible around the second molar regions was significantly higher (p < 0.01) in those with neurosensory disturbance (p < 0.01). The quality of bone measured by HU is associated with an increased risk of neurosensory disturbance, but the width of buccal bone is not.  相似文献   
85.
The renin-angiotensin system is thought to be involved in inflammatory processes such as periodontitis. However, its precise role is still unclear. Therefore, in the present study the expression of the angiotensin II type 1 receptor (AT1R) was investigated in inflamed human gingival tissue, and the possible involvement of the AT1R in interleukin-1β (IL-1β)-induced interleukin-6 (IL-6) production by cultured human gingival fibroblasts (HGFs) was also studied. Immunohistochemical staining revealed that inflammatory cells and fibroblast-like cells were positive for the AT1R. However, in healthy gingival tissue, AT1R staining was very weak. The levels of AT1R mRNA and AT1R protein increased in HGFs after stimulation with IL-1β. The levels of IL-1β-induced IL6 mRNA and IL-6 protein were significantly reduced in AT1R gene-silenced HGFs compared with control HGFs. The data suggest that the AT1R may be involved in the regulation of gingival inflammation by modulating IL-1β-induced IL-6 production in HGFs.  相似文献   
86.

Background

Recent studies have shown that intraoperative blood loss and blood transfusions promote postoperative recurrence of hepatocellular carcinoma (HCC). Hyperbaric oxygen therapy (HBOT) is a specific method of oxygen administration, which is independent of fluid therapy or blood transfusion. The aim of the present study was to assess the usefulness of acute HBOT after liver resection for patients with HCC in order to minimize the requirement for perioperative blood transfusions.

Patients and methods

Forty-one consecutive patients who showed Hb level < 9.0?mg/dl at the end of hepatic resection were randomly assigned to a control group (n = 21) or an HBOT group (n = 20). HBOT at 2.0?atm. with inhalation of 100% oxygen for a duration of 60?min was performed at 3, 24, and/or 48?h after the end of the hepatectomy. Regarding postoperative hepatic hemodynamics, liver function tests, and outcome data, prospective comparisons were completed in both groups. The two groups of patients were similar with respect to results from preoperative assessments.

Results

In six patients from the HBOT group, who experienced intraoperative major bleeding or showed fatal hepatic hypoxia (ShvO2 < 50%), the levels of ShvO2 and serum lactate were significantly improved after HBOT. When compared to the control group, the HBOT group showed better changes of ShvO2, serum lactate, and bilirubin levels for the first 3 postoperative days following surgery. Additionally, the HBOT group did not experience any fatal complications and had a lower incidence of postoperative hyperbilirubinemia than the control group. We also observed that postoperative NK cell activity and cancer-free survival in the HBOT group tended to be better than in the control group, although the differences did not reach significance.

Conclusion

These results suggest that acute HBOT after hepatectomy, aimed at reducing perioperative erythrocyte transfusions, may be employed for overcoming deficiencies in systemic and hepatic oxygen supply and thus diminishing postoperative complications. As an added benefit, such therapy may affect postoperative immunological responses and long-term survival after liver resection in HCC patients. Further analyses of the use of HBOT is warranted to confirm surgical outcome data and to assess the economic impact on healthcare costs.  相似文献   
87.
The present study was performed to compare the long-term effects of 24-h ambulatory blood pressure (BP) control with amlodipine versus valsartan on vascular damage in untreated hypertensive patients. Amlodipine and valsartan have benefits on cardiovascular mortality and morbidity in hypertensive patients. Although ambulatory BP is associated with severity of target-organ damage in hypertensive patients, beneficial effects of ambulatory BP control with amlodipine versus valsartan on vascular damage have not been compared. Pulse wave velocity (PWV), intima-media thickness (IMT) of the carotid arteries, urinary albumin excretion (UAE) and 24-h ambulatory BP were determined in 100 untreated hypertensive patients before and 12 months after the start of antihypertensive therapy with amlodipine or valsartan. Amlodipine and valsartan decreased ambulatory BP similarly, but the variability of 24-h and daytime ambulatory systolic BP was significantly reduced by amlodipine but not by valsartan. The reduced variability of ambulatory systolic BP caused by amlodipine significantly contributed to the improvement of PWV, although both drugs decreased PWV similarly. Carotid IMT was unaffected by treatment with either drug. Valsartan significantly decreased UAE independently of its depressor effect, but amlodipine had no effect on UAE. These results suggest that the 24-h control of ambulatory BP with amlodipine had functionally improved the stiffened arteries of hypertensive patients by the end of 12 months of treatment, in part through reducing BP variability, whereas ambulatory BP control with valsartan decreased the arterial stiffness to the same degree as amlodipine without affecting BP variability maybe through some pleiotropic effects.  相似文献   
88.
Inositol phospholipids phosphorylated on D3-position of their inositol rings (3-phosphoinositides) are known to play important roles in various cellular events. Activation of PI (phosphatidylinositol) 3-kinase is essential for aspects of insulin-induced glucose metabolism, including translocation of GLUT4 to the cell surface and glycogen synthesis. The enzyme exists as a heterodimer containing a regulatory subunit and one of two widely-distributed isoforms of the p110 catalytic subunit: p110alpha or p110beta. Activation of PI 3-kinase and its downstream AKT has been demonstrated to be essential for almost all of the insulin-induced glucose and lipid metabolism such as glucose uptake, glycogen synthesis, suppression of glucose output and triglyceride synthesis as well as insulin-induced mitogenesis. Accumulated PI(3,4,5)P(3) activates several serine/threonine kinases containing a PH (pleckstrin homology) domain, including Akt, atypical PKCs, p70S6 kinase and GSK.In the obesity-induced insulin resistant condition, JNK and p70S6K are activated and phosphorylate IRS-proteins, which diminishes the insulin-induced tyrosine phosphorylation of IRS-proteins and thereby impairs the PI 3-kinase/AKT activations. Thus, the drugs which restore the impaired insulin-induced PI 3-kinase/AKT activation, for example, by suppressing JNK or p70S6K, PTEN or SHIP2, could be novel agents to treat diabetes mellitus.  相似文献   
89.
90.
To investigate the prevalence of influenza viruses in feral water birds in the Southern Hemisphere, fecal samples of terns were collected on Heron Island, Australia, in December 2004. Six H2N5 influenza viruses were isolated. This is the first report of the isolation of the H2 subtype from shore birds in Australia. Phylogenetic analysis revealed that the M gene belonged to the American lineage of avian influenza viruses and the other genes belonged to the Eurasian lineages, indicating that genetic reassortment occurs between viruses of Eurasian and American lineages in free flying birds in nature.  相似文献   
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