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81.
The molecular mechanisms responsible for the development and/or progression of gastrinomas are largely unknown. Studies involving sporadic enteropancreatic neuro-endocrine tumors suggest that mutations in the MEN1 gene occur in some tumors and probably play an important role in their pathogenesis. In this study, we examined whether somatic mutations in the MEN1 gene are also responsible for sporadic gastrinomas and correlate with clinical manifestations of gastrinomas in Japanese patients. Genomic DNA was extracted from paraffin-embedded gastrinoma tissues from 12 patients. Nucleotide sequences in the MEN1 genes were determined by direct sequencing. We identified 6 mutations in 7 out of 12 examined gastrinomas (58%). The identified mutations were 1 non-sense, 2 missense, 1 deletion leading to frame shifts, 1 insertion and 1 splicing mutation. Identical mutations were found in three gastrinoma tissues. The age at surgery, the rate of hepatic metastasis, and tumor status were not significantly different in the 2 groups. This study demonstrates that alterations in the MEN1 gene are involved in about half of all sporadic gastrinomas, although no correlation between the presence of mutations and location and clinical phenotype or severity of disease has been found.  相似文献   
82.
We report on a 45-year-old patient with stage IIIc ovarian cancer, multiple brain metastases, and meningitis carcinomatosa. After three courses of initial chemotherapy, consisting of docetaxel and carboplatin, the patient underwent interval cytoreductive surgery, consisting of hyster-ectomy, bilateral salpingo-oophorectomy, omentectomy, appendectomy, and retroperitoneal lymphadenectomy. Then five courses of the same chemotherapy were given as adjuvant treatment. At the completion of the primary therapy, she achieved a complete remission. Ten months after the completion of the initial treatment, multiple brain metastases with meningitis carcinomatosa were detected. After four courses of the same chemotherapy, she again had a complete response, confirmed by cranial enhanced magnetic resonance imaging (MRI), and she felt well, with relief from the debilitating neurologic symptoms for 4 months. After this 4 months, her disease recurred, with meningitis carcinomatosa, and she requested supportive care only. She died 4 months after this recurrence. Chemotherapy can help to prolong life for some patients with multiple brain metastases and meningitis carcinomatosa from ovarian cancer.  相似文献   
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The aim of the present study was to examine the factors that contribute to the postmortem lung weight in acute fire fatalities (n=149) including those with lower (<60%) and higher (>60%) blood carboxyhemoglobin (COHb) levels (n=94 and 55, respectively). The control groups consisted of acute myocardial infarction/ischemia (AMI, n=99) and mechanical asphyxiation (n=85). For all cases (n=333), the lung and heart weights were independent of the postmortem time (4.5-72 h) and charring of the body. The combined weight of both lobes of the lung showed a significant gender difference (males>females, P<0.001), negative regression with respect to age (R=0.167, P<0.01) and positive regression with respect to heart weight (R=0.316, P<0.001). The gender difference was also significant for each cause of death even after being corrected using body height measurements. When the lung-heart weight ratio was estimated to diminish the influence of possible cardiogenic factors, the gender difference was insignificant for each cause of death among the non-elderly (<60 years of age). However, for elderly fire fatalities (>60 years of age), there was a gender difference (males>females) for the lower COHb group (P<0.05) and higher COHb group (P<0.001). A significant age-dependent difference (non-elderly>elderly) in the lung-heart weight ratio was observed for fire fatalities with a lower COHb and AMI among males and for fire fatalities with a higher COHb among females. Such gender- and/or age-dependent influences were not significant for fatal mechanical asphyxiation. These findings suggest that a person's heart weight may be a possible contributory factor to an increase in the lung weight in acute death, and that gender- and/or age-dependent susceptibilities may be additional factors that contribute to fire fatalities and AMI. In addition, elderly females appear to be most susceptible among fire casualties, and extreme cardiomegaly may also be a potential fatal risk factor.  相似文献   
85.
Although methemoglobinemia is an uncommon disorder, it should always be considered in the differential diagnosis of cyanosis. Major causes of acquired methemoglobinemia are nitrates, aniline, and analgesics, though rare cases have been reported to have been caused by automobile exhaust fumes. A 24-year-old man had inhaled a large amount of automobile exhaust fumes, intending to commit suicide. He had become unconscious, with dilated pupils and symptoms of cyanosis. Arterial hemoglobin oxygen saturation (SpO2) was 86%, with a methemoglobin level of 44.3% and a carboxyhemoglobin level of 0%, while electrolytes, blood urea nitrogen, creatine, and glucose measurement results were normal. He was treated with methylene blue 250 mg (approximately 4 mg/kg) through a nasogastric tube. Four hours after the treatment, because the methemoglobin level was slightly above normal (2.2%), we added 180 mg of methylene blue. The results of final arterial blood gas analysis were a methemoglobin level of 0.4% and a carboxyhemoglobin level of 0.8%. He recovered uneventfully and returned home by himself the next day. To summarize, we successfully treated, with methylene blue given through a nasogastric tube, a young man who had developed severe methemoglobinemia from inhaling automobile exhaust fumes.  相似文献   
86.
To enhance the efficacy of an inactivated vaccine against pseudorabies virus (PRV), we evaluated the adjuvant properties of Fc domain of IgG. A cell line expressing mouse IgG Fc chimera on its surface was established. We found that when PRV was propagated in the cells expressing the Fc chimera, PRV virion incorporated the Fc. Immunization of BALB/c mice with inactivated PRV harboring Fc, which had been propagated in the cells expressing Fc on its surface, induced higher antibody production against PRV and protected mice more effectively from lethal challenge of virulent strain, comparing to the immunization with normal inactivated virus. Virus harboring Fc has a great potential as a new inactivated vaccine.  相似文献   
87.
Masuda Y 《Clinical calcium》2005,15(1):95-100
In Japan, insufficient calcium (Ca) intake is serious problem for health which may be associated with the high prevalence of osteoporosis among the aged. The intake of most nutrients has been sufficient, however, the Ca intake has never been sufficient. Eggshell Ca has as much as 38% of Ca and low phosphorus content. Eggshell Ca was more soluble than Ca carbonate and was as much as milk products. Eggshell Ca has been shown to exhibit higher absorptivity and availability than Ca carbonate. Furthermore, it has been reported that eggshell Ca is more effective in increasing bone mineral density in ovariectomized osteoporotic rats. These results suggest that eggshell Ca could be beneficial for bone and we propose Ca fortified foods which contain eggshell Ca as a nutraceutical.  相似文献   
88.
It is controversial whether the ClC-3 protein, which is one of the voltage-dependent chloride channel ClC family members, is a candidate for the volume-sensitive outwardly rectifying (VSOR) Cl(-) channel per se or its regulator. Here, for the first time, we examined the single-channel properties of the VSOR Cl(-) channel in ventricular myocytes isolated from ClC-3-deficient mice. The single-channel current induced by cell swelling exhibited Cl(-) selectivity, mild outward rectification, and an intermediate unitary conductance (around 38 pS). A Cl(-) channel blocker, 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS), reversibly inhibited the outward current. These single-channel properties were identical with those in ClC-3 expressing wild-type ventricular myocytes. These results indicate that the single-channel activity of the VSOR Cl(-) channel is independent of the expression of ClC-3 proteins in mouse ventricular myocytes.  相似文献   
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