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81.
Secretogranin III (SgIII), a member of the granin protein family, is expressed specifically in neuronal and endocrine cells. To examine the precise localization of SgIII in the endocrine pancreas, pancreatic tissues of rats were analyzed immunocytochemically with a polyclonal anti-serum raised against rat SgIII. By light microscopy of semithin sections, the immunoreactivity for SgIII was readily detected in pancreatic A- and B-cells, faintly so in D-cells, and not at all in the exocrine pancreas. By immunoelectron microscopy, immunogold particles indicative of SgIII were observed in the peripheral regions of secretory granules, and universally in the pancreatic endocrine cells. Morphometrical analyses indicated that SgIII is most preferentially localized in the periphery of the secretory granule among granins. These findings suggest that SgIII is closely associated with the secretory granule membrane, serving to anchor the aggregates of other soluble constituents to the membrane.  相似文献   
82.
Insulin-like growth factor-1 receptor (IGF-1R) has been implicated in regulation in tumor growth. The results of previous studies performed by radioimmunoassay are conflicting, and the prognostic significance of IGF-1R expression in primary breast cancer is still controversial. IGF-1R expression was evaluated in formalin-fixed, paraffin-embedded tissue of 210 primary breast cancer patients by using anti-IGF-1R antibody. The clinicopathologic variables and 5-year disease-free survival were studied, and their correlations between IGF-1R expressions were investigated. IGF-1R overexpression was observed in 43.8% of tumors. IGF-1R overexpression had no correlation with prognosis or with other clinicopathologic parameters, such as age, tumor size, nodal status, histologic grade, hormone receptor status, and human epidermal growth factor 2 status. Though its prognostic value in breast cancer is limited, immunohistochemical evaluation of IGF-1R by using this monoclonal antibody may be useful in translational research using archived material.  相似文献   
83.
Invasive fungal infection (IFI) is a significant complication after allogeneic hematopoietic stem cell transplantation (HSCT); however, we have little information on its clinical features after reduced intensity cord blood transplantation (RICBT) for adults. We reviewed medical records of 128 patients who underwent RICBT at Toranomon Hospital between March 2002 and November 2005. Most of the patients received purine-analogbased preparative regimens. Graft-versus-host disease (GVHD) prophylaxis was a continuous infusion of either tacrolimus 0.03 mg/kg or cyclosporine 3 mg/kg. IFI was diagnosed according to the established EORTC/NIH-MSG criteria. IFI was diagnosed in 14 patients. Thirteen of the 14 had probable invasive pulmonary aspergillosis and the other had fungemia resulting from Trichosporon spp. Median onset of IFI was day 20 (range: 1-82), and no patients developed IFI after day 100. Three-year cumulative incidence of IA was 10.2%. Four of the 13 patients with invasive aspergillosis (IA) developed grade II-IV acute GVHD, and their IA was diagnosed before the onset of acute GVHD. The mortality rate of IFI was 86%. Multivariate analysis revealed that the use of prednisolone >0.2 mg/kg (relative risk 7.97, 95% confidence interval 2.24-28.4, P = .0014) was a significant risk factor for IA. This study suggests that IFI is an important cause of deaths after RICBT, and effective strategies are warranted to prevent IFI.  相似文献   
84.
85.
The distribution of binding sites of [125I]RTI-55 (3β-(4-iodophenyl)tropan-2β-carboxylic acid methyl ester), a phenyl tropane analog of cocaine, and the selective labelling of the dopamine transporter (DAT) were studied by in vitro and ex vivo autoradiography in the rat whole brain. Recent evidence has shown that RTI-55 binds to not only DAT but also serotonin transporter (5HTT). In the present study, in vitro autoradiography revealed that [125I]RTI-55 bound to the olfactory tubercle, the caudate putamen, the accumbens nucleus, the midline and lateral geniculate nuclei of the thalamus, the hypothalamic nuclei, the substantia nigra compact part, the subthalamic nucleus, the ventral tegmental area, the superior colliculus, the dorsal raphe nucleus, and the facial nucleus. Further, in the presence of clomipramine, a selective ligand for 5HTT, [125I]RTI-55 binding was remarkably inhibited in the midline and lateral geniculate nuclei of the thalamus, the hypothalamic nuclei, the superior colliculus, the dorsal raphe nucleus, and the facial nucleus, while [125I]RTI-55 binding remained in the olfactory tubercle, the caudate putamen, the accumbens nucleus, the substantia nigra compact part, the subthalamic nucleus, and the ventral tegmental area. These findings suggest that [125I]RTI-55 binds to 5HTT in the former areas and to DAT in the latter areas. It is therefore concluded that RTI-55 is a suitable ligand for studying the action of cocaine in whole brain regions, including the thalamus, the hypothalamus and the dorsal raphe nucleus, regions in which cocaine is thought to act evoking several neurological effects, e.g., analgesia and elevation of adrenocorticotropic hormone. DAT was also labelled selectively both in vitro and in vivo using [125I]RTI-55 combined with clomipramine. Therefore, radiolabelled RTI-55, combined with unlabelled clomipramine, which displaces its binding to 5HTT, also appears to be suitable for the selective imaging of DAT in vivo.  相似文献   
86.
Primary rhabdomyosarcoma of bone is exceedingly rare. We present a case of rhabdomyosarcoma of the iliac bone in a 32-year-old male. Histologically, the tumour consisted mainly of a uniform proliferation of elongated spindle cells arranged in a herring bone pattern, simulating fibrosarcoma. Focally there was a conventional embryonal pattern with scattered rhabdomyoblasts possessing an eosinophilic cytoplasm. Immunohistochemical studies disclosed expression of muscle markers such as desmin and muscle-specific actin, in both the embryonal and spindle-cell areas and myoglobin only in the embryonal areas. Such histological features are unusual for classical embryonal rhabdomyosarcoma. The anatomical site and age of the patient are also atypical.  相似文献   
87.
We recently obtained 3 cloned cell lines demonstrating the p53 mutation from a lung metastatic nodule of a rat transplantable osteosarcoma. In this study, we applied wild-type p53 gene transfer to the rat osteosarcoma cells by lipofection to investigate the effects on cell growth, expression of genes such as waf1/p21, bcl-2, and bax, and nucleosomal DNA fragmentation due to apoptosis. Reconstitution of the p53 gene inhibits cellular growth, and this growth-suppressive effect is partly due to apoptosis involving bcl-2 gene suppression in this tumor type. This rat osteosarcoma model is similar in biologic behavior to human cases and thus is very suitable for further investigation of tumorigenesis and gene therapy for osteosarcoma.  相似文献   
88.
PROBLEM: Early pregnancy factor (EPF) has been detected in pregnant bovine serum, and its activity appeared from 24 to 48 hr after insemination. However, in bovine in vitro fertilization (IVF), an EPF-like substance(s) had been detected in the culture medium of fertilized ovum. Therefore, we think that EPF and EPF-like substance(s) are very important materials for the development of the embryo. In this study, we examined the development of the embryo when fertilized bovine ova were cultured with IVF culture medium supplemented with EPF-positive or -negative serum. METHOD OF STUDY: EPF activity of each serum (fetal calf serum [FCS], calf serum [CS], estrus bovine serum, and pregnant bovine serum) was assessed by the bovine-rosette inhibition test. The sera were supplemented in TCM-199 culture medium, and IVF bovine ova were cultured with the media for 6 or 7 days, respectively. The culture media of each group were evaluated for EPF activity by the bovine-rosette inhibition test 48 hr after IVF. The cleavage rate of each group was calculated at 48 hr, and 6 or 7 days after IVF. The culture medium of cumulus cells was also tested for EPF activity. RESULTS: Only the pregnant bovine sera were EPF positive. All the culture media 48 hr after IVF became EPF positive. Additionally, the culture medium of cumulus cells did not have EPF activity. There was no significant difference in the cleavage rate of the EPF-positive and - negative sera 48 hr after IVF. However, the cleavage rate of EPF-positive sera tended to be higher than the negative sera. In contrast, the blastocyst development rates of EPF-positive sera were significantly higher than those of the negative sera 6 to 7 days after IVF (P < 0.05). CONCLUSIONS: The data suggest that an EPF-like substance(s) may be secreted from the in vitro fertilized bovine ovum but not from the cumulus cell, and that the EPF in the pregnant serum may accelerate the development of the bovine embryo in IVF.  相似文献   
89.
The purposes of the present study were to examine the response of the skin blood flux (SBF) in the paralyzed lower limbs of persons with spinal cord injury (PSCI) and to clarify the relationship between the SBF and core temperature during prolonged arm exercise. Eight male PSCI with lesions from T6 to L5 and six male control subjects (CS) participated in this study. The subjects rested for 60 min and then performed arm-cranking exercise at 20 W for 30 min at 25 °C. The tympanic membrane temperature (T ty) and SBF in the anterior thigh (SBFT) and in the posterior calf (SBFC) were continuously measured throughout the experiment. The SBFC did not change in either PSCI or CS during the experiment. The SBFT in four PSCI with high lesions (T6 to T12), remained unchanged during exercise. The SBFT in the other four PSCI with low lesions (T12 to L5, SBFT+) began to elevate markedly when the T t, exceeded a threshold temperature of 36.69 °C. The pattern of increase of SBFT in SBFT+ was similar to that in CS, although onset of the increase in SBFT was delayed and the peak of SBFT during exercise was significantly lower in comparison with the CS. We consider that these differences between the SBFT+ and CS were largely attributable to the lowerT ty in the former group, which took a prolonged time to reach the threshold of 36.69 °C.  相似文献   
90.
This study was designed to explore whether it was possible to evaluate the severity of VSD, PDA, and ASD by measuring brain natriuretic peptide (BNP) levels. We also investigated normal BNP levels in children to provide a baseline for our study. We measured BNP levels in 253 normal children, including 11 normal neonates, and in 91 VSD patients, 29 PDA patients, and 34 ASD patients. BNP levels showed no age-related differences in normal children (the mean value: 5.3 +/- 3.8 pg/ml). In the healthy neonates, BNP levels rose from 10.4 +/- 11.9 pg/ml in cord blood to 118.8 +/- 83.2 pg/ml on day 0, then fell to 15.3 +/- 7.8 pg/ml by day 7. In VSD and PDA patients, BNP levels correlated significantly with Qp/Qs, LVEDV, and peak RVP/LVP. In ASD patients, BNP levels correlated with Qp/Qs and RVEDV. Especially, in VSD patients, as an index corresponding to 1.5-2.0 of the Qp/Qs ratio, BNP levels of 20-35 pg/ml were found to be best with regard to both sensitivity and specificity. In the healthy neonates, BNP levels changed rapidly after birth. In VSD, PDA, and ASD patients, BNP levels were well-correlated with the severity of the disease. Especially, in VSD patients, it that appears BNP levels may be useful in evaluating surgical indications, with 20-35 pg/ml levels being the appropriate cut-off value.  相似文献   
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