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61.
Breast, prostate, lung, and other cancers can metastasize to bone and lead to pathological fracture. To lay the groundwork for new clinical techniques for assessing the risk of pathological fracture, we identified relationships between density measured using quantitative computed tomography (rhoQCT), longitudinal mechanical properties, and ash density (rhoAsh) of cortical bone from femoral diaphyses with and without metastatic lesions from breast, prostate, and lung cancer (bone with metastases from six donors; bone without metastases from one donor with cancer and two donors without cancer). Moderately strong linear relationships between rhoQCT and elastic modulus, strength, and rhoAsh were found for bone with metastases (0.73相似文献   
62.
Effects of recombinant human endostatin on a human neuroblastoma xenograft   总被引:1,自引:0,他引:1  
New antitumor agents must be added to the current neuroblastoma treatment regimens to improve the clinical results. We investigated whether recombinant human endostatin (rhEndostatin), an antiangiogenic agent, is effective against human neuroblastoma in the human neuroblastoma xenograft model designated TNB9. When tumors on the back of nude mice grew to a weight of 90-95 mg, rhEndostatin 10 mg/kg/day was administered subcutaneously every day for 10 consecutive days. Mean relative tumor weight in mice administered rhEndostatin (n=5) was significantly less than that in controls (n=12) on days 2, 4, and 6 after the start of administration (p<0.01 on day 2, p<0.05 on days 4 and 6), and regression of tumor growth (TRW<1.0) was marked on day 2. The maximum inhibition rate (MIR) by rhEndostatin was 46.4%, indicating inefficacy, but it may not be appropriate to apply Battelle Columbus Laboratories criteria to this experimental model because rhEndostatin is a protein. After day 8, tumors in the experimental group increased in weight and were not statistically significantly different from those in controls. Recombinant human endostatin was used in tumors in the arterial system of the mouse in this experiment because eventually rhEndostatin, not recombinant mouse endostatin, may be used to treat advanced neuroblastoma in the clinical setting. The results show that there is little cross-reactivity of rhEndostatin with the human and mouse models and indicate that rhEndostatin could become an effective agent for the treatment of human neuroblastoma.  相似文献   
63.
Interest in quality assurance(QA) in clinical laboratories in Japan has increased over the past 30 years. We have however been lagging behind countries such as the USA, Canada and the UK in QA of clinical microbiology. The main problem of QA in Japan is human resources. There are only about 400 laboratory physicians certified by the Japanese Society of Laboratory Medicine(JSLM). Almost no academics in microbiology are interested in QA and they mostly lack clinical competence. There is a small number of faculty positions, and promotions are mostly based on research productivity while medical graduates are increasingly drawn to bench work for basic, short-term research. The Japanese Society for Clinical Microbiology (JSCM) was established in 1990 in order to promote the development of clinical microbiology and its relevant fields in Japan. And 2001 was a milestone in sustained efforts of the JSLM to initiate qualifying examinations of medical technologists(MT) in clinical microbiology. 105 MT in clinical microbiology were newly certified by the Joint Committee of JSCM, JSLM, Japanese Association of Medical Technologists (JAMT) and College of Clinical Pathology of Japan(CCPJ). The certified MTs have appropriate educational background and are well motivated. With good on-the-job training, they are expected to perform effectively various tasks, including laboratory management. Recent radical changes in the health care delivery system have also had serious implications on laboratory services and QA of microbiological tests. The primary goal of the clinical microbiology laboratory is to provide accurate diagnostic testing and high-quality service at a low cost for its customers. It is believed that the Joint Committee and the newly certified MTs will contribute to narrowing the gap between Japan and other countries in clinical microbiology.  相似文献   
64.
Dysfunction of the dopaminergic system has been suggested as a pathogenic mechanism in neuroleptic malignant syndrome. Therefore, we examined the complete coding sequences of the dopamine D2 receptor (DRD2) gene for structural abnormalities in 12 patients with a history of NMS, including two cases of familial NMS. Mutational analysis was performed by denaturing gradient gel electrophoresis (DGGE), a highly sensitive technique for detecting sequence differences. We found in one patient with a history of NMS a nucleotide substitution at codon 310 (CCG→TCG) of exon 7 of the DRD2 gene which predicts the replacement of proline to serine in the third cytoplasmic loop of the receptor, a part of the receptor that interacts with G-proteins. A larger series of patients with NMS needs to be investigated to establish whether this allele is associated with an increased susceptibility to NMS. © 1995 Wiley-Liss, Inc.  相似文献   
65.
66.
BACKGROUND: Tachykinins are involved in the development of bronchial inflammation and airway hyperresponsiveness (AHR); however, the role of the neurokinin-1 (NK(1)) receptor in acid-aerosol-induced bronchial impairment in asthmatic patients remains controversial. METHODS: To investigate the effects on the NK(1) receptor antagonist FK888 the neurokinin-2 (NK(2)) receptor antagonist SR48968 on sulfuric-acid (H(2)SO(4))-induced AHR in guinea pigs, specific airways resistance (sRaw) and airways responsiveness to methacholine (MCh) were measured before and after 6 h of exposure to H(2)SO(4) aerosol (pH 1.7, 82 mg/m(3)) in ovalbumin-sensitized guinea pigs. RESULTS: Airway responsiveness to MCh significantly increased (p<0. 05) after the exposure, however sRaw did not. Treatment with FK888 significantly inhibited (p<0.05) H(2)SO(4)-induced AHR in a dose-dependent manner, as did SR48968. CONCLUSIONS: These results suggest that not only NK(2) but also NK(1) receptors might have important roles in the development of acid-aerosol-induced AHR.  相似文献   
67.
To clarify the correlation of genomic alterations with clinical and histological features, we performed metaphase comparative genomic hybridization analysis on 20 primary cutaneous melanomas, which were obtained by laser capture or manual microdissection, and 16 melanoma cell lines. There were no differences in the average number of aberrations between acral melanomas (AM) and non-AM, although gains of 5q and 11q13 were more frequent (P=0.05) and 10q loss was less frequent (P=0.01) in AM than in non-AM. Although tumor thickness is considered a measurable estimate of clinical expression, there were no differences in the average number of aberrations among 4 groups, classified by thickness of the tumor. While the majority of aberrations were equally distributed among the 4 groups, 6p gains were found only in the thickest tumors. Patients with 6p or 1q gains had a lower overall survival rate than those without them (P=0.0002 or P=0.013). While gains of 1q, 2q, 3p, 3q, 7q, 20p, and 20q were more frequent in the cell lines than in the primary tumors (P<0.01), losses of 6q, 9p, 10p, and 10q were equally found in both cell lines and primary tumors. The present study showed that chromosomal aberrations had already occurred in the thinner tumors, and that 6p and 1q gains may be a prognostic factor.  相似文献   
68.
Ossifying fibromyxoid tumor (OFMT) of soft parts is a recently described, rare but morphologically distinctive soft tissue tumor. The histogenesis of this lesion remains uncertain, although several immunohistochemical and ultrastructural features suggest that it is an unusual neural tumor, possibly of Schwann cell origin. We report here a case of a malignant variant of OFMT that occurred in the foot of a 52-year-old man. The karyotype of a pulmonary metastasis exhibited the following complex numeric and structural aberrations:72 approximately 74,XXY,-5,+6,+del(8)(p21),del(9)(p22),+10,der(11)t(3;11)(p21;p15),del(12) (q13),der(13)t(5;13)(q13;q34),+18,+19,+20,-22 [cp10]. A kidney metastasis exhibited the following karyotypic abnormalities: 46,XY,add(3)(p11),+der(3)t(3;?;11)(3qter-->3p11::?::11q13-->11qter), -5,del(8)(p21),add(9)(q22),del(9)(p22),der(11)t(3;11)(p21;p15),del(12)(q13),+der(13)t(5;13) (q13;q34),-22. To our knowledge, this is the first reported case of OFMT in which clonal chromosomal aberrations have been shown.  相似文献   
69.
70.
Widespread use of zebrafish (Danio rerio) in genetic analysis of embryonic development has led to rapid advances in the technology required to generate, map and clone mutated genes. To identify genes involved in the generation and regulation of vertebrate circadian rhythmicity, we screened for dominant mutations that affect the circadian periodicity of larval zebrafish locomotor behavior. In a screen of 6,500 genomes, we recovered 8 homozygous viable, semi-dominant mutants, and describe one of them here. The circadian period of the lager and lime (lag(dg2)) mutant is shortened by 0.7 h in heterozygotes,and 1.3 h in homozygotes. This mutation also shortens the period of the melatonin production rhythm measured from cultured pineal glands, indicating that the mutant gene product affects circadian rhythmicity at the tissue level, as well as at the behavioral level. This mutation also alters the sensitivity of pineal circadian period to temperature, but does not affect phase shifting responses to light. Linkage mapping with microsatellite markers indicates that the lag mutation is on chromosome 7. A zebrafish homolog of period1(per1) is the only known clock gene homolog that maps near the lag locus. However, all sequence variants found in per1 cDNA from lag(dg2) mutants are also present in wild type lines, and we were unable to detect any defect in per1 mRNA splicing, so this mutation may identify a novel clock gene.  相似文献   
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