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Pheochromocytoma usually shows prominent nuclear atypia, but the presence of such atypical cells is known to be an unreliable predictor of malignancy. DNA ploidy of pheochromocytomas has been analyzed by flow cytometry or photospectrometry on paraffinem-bedded tissue, but the results were controversial. We performed DNA analysis on cytology specimens of 11 pheochromocytomas using an image analysis system. All tumors had a mixed pattern of a large population of diploid cells and a small population of polyploid cells. DNA content correlated with nuclear size, and larger cells had more DNA content. Such larger tumor cells had polyploid nuclei, such as 4 C, 8 C, 16 C, and 32 C, in both malignant and benign pheochromocytomas. The larger polyploid nuclei may result from difficulty of duplication at the mitotic phase of the cell cycle.  相似文献   
4.
The aim of this study was to compare the estimated public medical care cost of measures to address metallic dental restorations (MDRs) for head and neck radiotherapy using high-energy mega-voltage X-rays. This was considered a first step to clarify which MDR measure was more cost-effective. We estimated the medical care cost of radiotherapy for two representative MDR measures: (i) with MDR removal or (ii) without MDR removal (non-MDR removal) using magnetic resonance imaging and a spacer. A total of 5520 patients received head and neck radiation therapy in 2018. The mean number of MDRs per person was 4.1 dental crowns and 1.3 dental bridges. The mean cost per person was estimated to be 121 720 yen for MDR removal and 54 940 yen for non-MDR removal. Therefore, the difference in total public medical care cost between MDR removal and non-MDR removal was estimated to be 303 268 800 yen. Our results suggested that non-MDR removal would be more cost-effective than MDR removal for head and neck radiotherapy. In the future, a national survey and cost-effectiveness analysis via a multicenter study are necessary; these investigations should include various outcomes such as the rate of local control, status of oral mucositis, frequency of hospital visits and efforts of the medical professionals.  相似文献   
5.

Background:

Despite the clinical relevance of angiotensin I-converting enzyme (ACE)inhibitors, their effects on impaired vascular function in patients and animals with chronic heart failure (CHF) have not been fully understood. This study was undertaken to determine whether long-term treatment with an ACE inhibitor improved the altered contractile properties of vessels from rats with CHF.

Methods and Results:

Twelve weeks after coronary artery ligation, the rats were sacrificed and the isometric tension development of thoracic aorta, pulmonary artery, and mesenteric artery with and without endothelium was examined. Contractile responses to norepinephrine and prostaglandin F2α were augmented in endothelium-intact, but not in endothelium-denuded, thoracic aorta and pulmonary artery segments of the rat with CHF. The contractile response to angiotensin II was augmented in endothelium-denuded mesenteric artery segments of the rat with CHF, which was attenuated by indomethacin or diclofenac sodium but not by bunazosin. Trandolapril (3 mg/kg/d) was administered orally from the 2nd to 12th week after the operation. Treatment with trandolapril reversed the augmented contractile response of the rat with CHF to norepinephrine, prostaglandin F2α, and angiotensin II almost to the levels in the sham-operated rat.

Conclusions:

The results demonstrate that an ACE inhibitor is capable of reversing altered vascular function in the rat with CHF, suggesting that vascular beds are possible sites of action for ACE inhibitors in the therapy for CHF.  相似文献   
6.
BackgroundMeningitis is a common emergency disease. Signs and symptoms easily observed at the bedside are needed because early recognition of the possibility of meningitis is necessary for the decision to perform lumbar puncture. Jolt accentuation of headache has been reported to be the most sensitive diagnostic test; however, limited articles have reproduced its sensitivity.MethodsThis is a single-center retrospective medical record review between 2007 and 2012. We diagnosed meningitis based on the criterion standard that cerebrospinal fluid total cells is more than 5/mm3, in accordance with previous studies. All diagnostic and management decisions including Kernig sign, nuchal rigidity, and jolt accentuation of headache were at the physician's discretion. We calculated the sensitivity and specificity of well-known signs and symptoms of meningitis and, especially, compared the efficacy of jolt accentuation of headache with previous studies.ResultsWe investigated 531 adult patients who were suspected of meningitis and had lumbar puncture performed. Of these patients, 139 had meningitis. Background characteristics and vital signs were not clinically different between the 2 groups, although classic tetralogy of bacterial meningitis (fever, nuchal rigidity, mental disturbance, and headache) was worth investigated. The sensitivity and specificity of jolt accentuation of headache were 63.9% (95% confidence interval, 51.9%-76.0%) and 43.2% (34.7%-51.6%), respectively.ConclusionThe absence of jolt accentuation of headache test cannot, on its own, accurately rule out meningitis in adults. Further studies are warranted to reproduce this result and to discover better bedside diagnostic tests.  相似文献   
7.

Background

Sudden bath-related deaths occur frequently in Japan, particularly among elderly people. However, the precise mechanism of bath-related death remains uncertain, and effective prevention strategies have not been established.

Methods

Cases of bath-related deaths (n = 3289) were selected from all cases handled by the Tokyo Medical Examiner’s Office from 2009 to 2011 (N = 41 336). The ages and occurrence dates were examined, and major autopsy findings, including toxicological analysis, were evaluated for the autopsied cases (n = 550).

Results

Most cases occurred in individuals older than 60 years of age during winter. Analysis of autopsy findings revealed water inhalation signs in many cases (n = 435, 79.1%). Circulatory system diseases constituted more than half of the pathological findings regarding factors that may have contributed significantly to death (n = 300, 54.5%), and cardiac lesions were the most common pathological finding (n = 250, 45.5%). However, approximately one-third of the cases exhibited no remarkable pathological findings (n = 198, 36.0%). A quarter of all cases involved blood ethanol levels that exceeded 0.5 mg/mL (n = 140).

Conclusions

The results suggested that drowning plays an important role in the final process of bath-related death. Circulatory system diseases may be the primary underlying pathology; however, there were variations in the medical histories and pathologies of cases of bath-related death. From a preventive perspective, family members should pay attention to elderly people with circulatory system diseases during bathing, particularly in winter. Additionally, the notion that ill or inebriated individuals should not take baths should be reinforced.Key words: bath-related death, sudden death, forensic autopsy, medical examiner  相似文献   
8.
Several studies suggest that heteromerization between μ (MOP) and δ (DOP) opioid receptors modulates the signalling properties of the individual receptors. For example, whereas activation of MOP receptors by an agonist induces G protein-mediated signalling, the same agonist induces β-arrestin-mediated signalling in the context of the MOP-DOP receptor heteromer. Moreover, heteromer-mediated signalling is allosterically modulated by a combination of MOP and DOP receptor ligands. This has implications in analgesia given that morphine-induced antinociception can be potentiated by DOP receptor ligands. Recently reagents selectively targeting the MOP-DOP receptor heteromer such as bivalent ligands, antibodies or membrane permeable peptides have been generated; these reagents are enabling studies to elucidate the contribution of endogenously expressed heteromers to analgesia as well as to the development of side-effects associated with chronic opioid use. Recent advances in drug screening technology have led to the identification of a MOP-DOP receptor heteromer-biased agonist that activates both G protein-mediated and β-arrestin-mediated signalling. Moreover, this heteromer-biased agonist exhibits potent antinociceptive activity but with reduced side-effects, suggesting that ligands targeting the MOP-DOP receptor heteromer form a basis for the development of novel therapeutics for the treatment of pain. In this review, we summarize findings regarding the biological and functional characteristics of the MOP-DOP receptor heteromer and the in vitro and in vivo properties of heteromer-selective ligands.

LINKED ARTICLES

This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2  相似文献   
9.
Kiba T 《Pancreas》2004,29(2):e51-e58
Substantial new information has accumulated on the mechanisms of secretion, the development, and regulation of the gene expression, and the role of growth factors in the differentiation, growth, and regeneration of the pancreas. Many genes that are required for pancreas formation are active after birth and participate in endocrine and exocrine cell functions. Although the factors that normally regulate the proliferation of the pancreas largely remain elusive, several factors to influence the growth have been identified. It was also reported that the pancreas was sensitive to a number of apoptotic stimuli. The autonomic nervous system influences many of the functions of the body, including the pancreas. In fact, the parasympathetic nervous system and the sympathetic nervous system have opposing effects on insulin secretion from islet beta cells; feeding-induced parasympathetic neural activity to the pancreas stimulates insulin secretion, whereas stress-induced sympathetic neural activity to the pancreas inhibits insulin secretion. Moreover, it has been reported that the autonomic nervous system is one of the important factors that regulate pancreatic regeneration and stimulate the carcinogenesis. The present review focuses on the relationships between the autonomic nervous system and the pancreas, and furthermore, presents evidence of the autonomic nervous system-related pancreatic regeneration and carcinogenesis.  相似文献   
10.
[Purpose] The purpose of this study was to investigate how a stretching torque affects muscular contractures. [Subjects] The subjects of this study were 48 male Wistar rats. [Methods] Subjects were divided into 4 groups as follows: Group 1 was the control; Group 2 had muscles in continuous fixation; Group 3 had muscles stretched in the direction of dorsiflexion by a spring balancer set at a torque of 0.3N for a period of 30 minutes after continuous fixation; and Group 4 had muscles stretched in the direction of dorsiflexion by a spring balancer set at a torque of 3.0N for a period of 30 minutes after continuous fixation. Joint fixation periods were for 2 and 4-weeks. Ankle joint range of motion and soleus flexibility were analyzed. [Results] For the 2-week joint fixation, soleus flexibility in Group 4 showed an increase compared with that of Group 3. For both fixation periods, range of motion in Group 4 showed an increase compared with that of Group 3. [Conclusion] For both fixation periods, stretching improved joint range of motion. In the 2-week joint fixation, soleus flexibility improved. However, soleus flexibility did not improve in the 4-week joint fixation.Key words: Muscular contracture, Stretching, Muscular flexibility  相似文献   
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