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1.
Reviewing the definition of "elderly"   总被引:1,自引:0,他引:1  
Conventionally, "elderly" has been defined as a chronological age of 65 years old or older, while those from 65 through 74 years old are referred to as "early elderly" and those over 75 years old as "late elderly." However, the evidence on which this definition is based is unknown. We have attempted to review the definition of elderly by analyzing data from long-term longitudinal epidemiological studies, and clinical and pathological studies that have been accumulated at the Tokyo Metropolitan Geriatric Hospital and the Tokyo Metropolitan Institute of Gerontology. Our recommendation might be a starting point in developing a strategy for a successful society by reviewing the definition of elderly based on comprehensive evidence in all aspects of social, cultural and medical sciences.  相似文献   
2.
Lobular carcinoma of the male breast is very rare, because lobules do not exist in the male mammary gland. Seven cases of lobular carcinoma of the male breast have been reported in Europe and U.S.A., although no case in Japan. We encountered a very rare case of the lobular carcinoma of 74-year-old male breast. Histopathological examinations of both primary tumor and recurrent tumors of the skin led to the diagnosis of lobular carcinoma.  相似文献   
3.
Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant systemic fibrovascular dysplasia. Although hepatic vascular shunts are often observed in HHT, the responsible pathological mechanism is unknown. This issue was addressed by performing a 3-dimensional reconstruction study of the hepatic microvasculature of an HHT-involved liver in a 79-year-old woman. Clinical observation revealed high-output congestive heart failure and hepatic encephalopathy due to arteriovenous and portovenous shunts, respectively. Angiography revealed tortuous dilation of hepatic arterial branches and intrahepatic arteriovenous shunts. The 3-dimensional analysis of the autopsy liver revealed focal sinusoidal ectasia, arteriovenous shunts through abnormal direct communications between arterioles and ectatic sinusoids, and portovenous shunts due to frequent and large communications between portal veins and ectatic sinusoids. Type 1 HHT was suggested by the lack of endoglin immunoreactivity in the liver. The 3-dimensional reconstruction study of hepatic microvasculature was successful in identifying the pathological changes responsible for the intrahepatic shunts in HHT.  相似文献   
4.
Seroepizootiologic surveys among wild rodents were carried out in Japan and Far East Russia in 1995 and 1996. Seropositive animals were only identified in Clethrionomys rufocanus (23/134) in Hokkaido, Japan. On the other hand, seropositives were identified in C. rufocanus (1/8), Apodemus agrarius (2/66), Apodemus spp. (2/26) and Microtus fortis (3/22) in Vladivostok, Far East Russia. Total RNA was isolated from lungs of seropositive animals and the S genome segments were amplified by PCR, cloned and sequenced. The S and M genomes of hantavirus, derived from Japanese C. rufocanus (Tobetsu genotype), were most closely related with Puumala viruses (76-79% nucleotide and 95% amino acid identities for S genome, 70-78% nucleotide and 87-92% amino acid identities for M genome). The recombinant nucleocapsid protein of Tobetsu genotype was antigenically quite similar with that of Sotkamo. These suggest that the virus endemic in Japanese C. rufocanus belongs to Puumala virus. Phylogenetic analysis indicates that the genotype forms a distinct lineage within Puumala viruses. Partial S segment (1-1251 nt), derived from seropositive M. fortis in Vladivostok, was sequenced and analyzed. The S genome segment, which was designated Vladivostok genotype, was most closely related with Khabarovsk virus (79% nucleotide and 90% amino acid identities) which was isolated from M. fortis.  相似文献   
5.
BACKGROUND: The serum erythropoietin level increases markedly during chemotherapy for leukemia. A number of hypotheses have been built for the mechanism, none of them satisfactory. Difficulty in evaluating bone marrow activity hampers the elucidation. Therefore, we focused on patients who had non-hematological cancer and no evidence of bone marrow suppression. METHODS: Twelve patients, who had lung cancer (four with small cell cancer and eight with non-small cell cancer) and who had not undergone any chemotherapy, were studied. During chemotherapy, we measured serum erythropoietin, serum iron, unsaturated iron binding capacity and hemoglobin concentration in these patients. RESULTS: The serum erythropoietin level before chemotherapy (10.8 +/- 7.4 mU/ml) was within the normal range but the peak values after the first treatment (73.4 +/- 90.4 mU/ml) increased in all patients. In the patients with small cell cancer, a transient but marked increase in erythropoietin value (204.6 +/- 167.3 mU/ml) was observed after each session of chemotherapy while hemoglobin concentration decreased gradually. Throughout treatments, elevation of the serum iron concentration and concomitant reduction of unsaturated iron binding capacity were observed after each session of chemotherapy. They regained their original values whilst the serum erythropoietin level decreased after each chemotherapy session was completed. CONCLUSIONS: It is suggested that the suppression of erythroid marrow by chemotherapeutic agents causes the changes in serum erythropoietin level during chemotherapy in patients with lung cancer.   相似文献   
6.
A newly designed flow support catheter with a supporting wire mesh cage which can be expanded into a tubular configuration and then readily reduced was evaluated in mongrel dogs. Regional myocardial blood flow (RMBF) was measured using the radioactive microsphere technique in the area of both balloon-denuded instrumented and control non-instrumented coronary arteries following placement of either a fixed-wire or a higher profile rapid exchange flow support catheter. At 5, 20, and 180 min following delivery and expansion of either device, RMBF was not significantly different in left ventricular subepicardium and subendocardium perfused by the instrumented vs. the control coronary arteries. Angiography demonstrated widely patent instrumented arteries in 15/18 dogs; in no dog was side branch occlusion observed. Significant cage thrombus deposition was seen angiographically in 3 animals causing temporary total coronary occlusion in 1. Following reduction and removal of the flow support catheter, vessel patency was present in all dogs. The flow support catheter is an effective endovascular stenting device capable of providing structural arterial support, while simultaneously maintaining distal coronary blood flow. It is envisioned that the primary application of this catheter will be to enable primary salvage of vessels acutely injured during coronary angioplasty, by “tacking up” intimal flaps for an extended period. It may also provide a bridge to emergency surgical revascularization.  相似文献   
7.
J Oral Pathol Med (2012) 41 : 372–378 Objectives: A precancerous condition is a lesion that, if left untreated, leads to cancer or can be induced to become malignant. In the oral region, leukoplakia is a lesion that has been regarded as precancerous. In cases of oral carcinoma, we have frequently noticed that a type of leukoplakia histologically demonstrating hyper‐orthokeratosis and mild atypia (ortho‐keratotic dysplasia; OKD) is often associated with carcinoma, either synchronously or metachronously. Therefore, we consider OKD‐type leukoplakia to be a true precancerous lesion. Materials and Methods: In an attempt to clarify the relationship between OKD as a precancerous condition in the oral mucosa and telomere length, we estimated telomere lengths in this type of leukoplakia using quantitative fluorescence in situ hybridization, and also quantified the frequency of anaphase–telophase bridges (ATBs) in comparison with squamous cell carcinoma in situ (CIS) and the background tissues of CIS and OKD. Results: Ortho‐keratotic dysplasia was frequently associated with squamous cell carcinoma (45.0%) and showed significantly shorter telomeres than normal control epithelium, CIS, or the background of CIS or OKD. The frequency of ATBs was much higher in OKD than in control epithelium or CIS. Conclusion: Ortho‐keratotic dysplasia appears to be frequently associated with carcinoma, chromosomal instability, and excessively shortened telomeres, not only in the lesion itself but also in the surrounding background. Therefore, when this type of leukoplakia is recognized in the oral region, strict follow‐up for oral squamous cell carcinoma is necessary, focusing not only on the areas of leukoplakia, but also the surrounding background.  相似文献   
8.
Seawater sample from the coral reefs of the Kerama Islands of Okinawa were assessed for the presence of carotenoid-producing bacteria. Results of 16S rDNA analysis of the bacteria obtained from the isolated bacteria showed unique patterns that were different from those of the bacteria obtained from the ordinary marine area. Phylogenetic analysis revealed a slight correlation with the statistical analysis of the PDA chart patterns. The results suggest that useful materials for human health such as carotenoids can be extracted from many carotenoid-producing bacteria such as those found the coral reefs the Kerama Islands.  相似文献   
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