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101.
An immediate-early gene product of baculovirus, IE1, is essential for viral gene expression and for viral DNA replication. It has been demonstrated for Autographa californica nuclear polyhedrosis virus (AcNPV) that the C-terminal region of IE1 is required for dimerization. And the acidic N-terminal region of IE1 has been identified as the activation domain. We constructed an N-terminal 267 amino acid (a.a.) truncated mutant of Bombyx mori nuclear polyhedrosis virus (BmNPV) IE1, which was defective as a transactivator of a viral early gene (p35) promoter. We then examined possible IE1 antagonistic functions of this defective IE1, IE1TN, in BmNPV-infected cells. A transient expression experiment demonstrated that IE1TN strongly repressed the activation of the hr5-dependent p35 promoter derived from BmNPV infection. In addition, DpnI assay elucidated an inhibitory effect of IE1TN on the hr5-dependent replication of plasmid in BmN cells induced by NPV infection. A marked reduction in the production of virus was observed when the BmN cells were infected with BmNPV after transfection with IE1TN-expression plasmids. These results suggested that IE1TN could act as an IE1 antagonist in silkworm cells infected with BmNPV. We then analyzed the ability of IE1TN to inhibit the multiplication of BmNPV using transgenic silkworms. The BmNPV-resistance of the transgenic silkworms was very weak, suggesting insufficient expression of the transgene product, IE1TN.  相似文献   
102.
In pediatric patients, the lower body weight limits the volume of contrast medium. Conventionally, angiocardiography is carried out with a single large bolus injection of contrast material. Angiocardiograms are used in pediatric patients with complex congenital heart diseases. In patients with complex congenital heart disease, especially with MAPCA, the volume of contrast medium used may be excessive. This would allow further injection to provide additional information. To reduce contrast medium used in the angiocardiogram in pediatric patients, we decided to use electrocardiogram (ECG)-gated multiple diastolic injection (EMDI). Three small boluses were injected during the diastolic phase of three consecutive cardiac cycles using a commercially-available power injector. Seventy-eight ventriculograms (47 left ventriculograms and 31 right ventriculograms) using EMDI were carried out on 53 patients with congenital heart disease. Total contrast medium volume with EMDI ventriculograms (mean [±SD] per body weight: 0.72 [±0.25] ml/kg) was significantly smaller than with conventional injection (1.01 [±0.36] ml/kg) (p <0.001). The grades of ventriculograms with EMDI tended to be slightly better than those with conventional injection (statistically not significant, p = 0.478). No short-run type premature ventricular contraction (PVC)s or intramural injection occurred in the ventriculograms with EMDI. PVCs tended to be less frequent in the ventriculograms with EMDI than in those with conventional injection (statistically not significant, p = 0.131). EMDI may be worthwhile in reducing ventricular ectopy when checking ventricular function by angiography, since hemodynamic conditions are less affected by small quantities of contrast medium and only during the filling phase of the ventricles. In conclusion, EMDI may be a useful method for reducing complications of ventriculography in pediatric angiocardiography.  相似文献   
103.
Two cases of localized pseudomyxoma peritonei in the female pelvic cavity associated with a ruptured appendiceal mucocele and ovarian involvement that mimicked ovarian carcinomatous peritonitis were evaluated. Subtle omental irregularity adjacent to the cecum may suggest the hidden appendiceal origin reflecting localized carcinomatous peritonitis caused by the occult rupture of the mucocele. Mucinous fluid-like materials were localized in the pelvic cavity with scalloping of the uterus, which may be the diagnostic finding of pseudomyxoma peritonei.  相似文献   
104.
BACKGROUND: Nonspecific interstitial pneumonia (NSIP) has recently been described as a distinct clinicopathological entity among idiopathic interstitial pneumonias (IIP), having more favorable prognosis than usual interstitial pneumonia (UIP). Although NSIP was initially reported to also occur in patients with interstitial pneumonia associated with collagen vascular diseases (IP-CVD), the prevalence of NSIP and its prognostic significance in IP-CVD remains to be determined. Thus, we attempted to clarify clinical characteristics and prognostic significance of NSIP in IP-CVD. METHODS: We histologically examined surgical lung biopsies from 43 patients with IP-CVD based on a current classification of interstitial pneumonias, and compared the clinical characteristics and prognostic significance of NSIP with UIP in IP-CVD. We also studied 98 patients with biopsy-proven NSIP and UIP in IIP, and compared the prognostic significance of histopathologic subclassification in IIP with that in IP-CVD. RESULTS: In IP-CVD, twenty-six patients (60%) were classified as NSIP, 17 (40%) as UIP. In contrast, 76 (77%) were categorized into UIP and 22 (23%) into NSIP of the patients with IIP. No significant difference in survival rates was observed between UIP and NSIP in IP-CVD (p = 0.3863), while, in IIP, NSIP has a significant better survival than UIP (p = 0.022). CONCLUSIONS: These results suggest that NSIP is more common histologic pattern than UIP in IP-CVD and, unlike in IIP, the prognosis of NSIP patients may not be different from that of UIP patients in IP-CVD.  相似文献   
105.
We recently isolated mutant PC12 cell clones (PC84 cells) by transfection of PC12 cells with nerve growth factor (NGF) cDNA. These cells secreted active NGF and extended short processes, but proliferated faster than the parental PC12 cells. Because the expression level of p75, a low-affinity receptor for NGF, was significantly low, we suspected that NGF signaling via p75 was necessary for the growth arrest of the PC12 cells, and this was shown to be the case by repressing p75 function in PC12 cells. In this study, we examined the downstream signaling of p75, which would ultimately evoke the growth arrest. NGF is known to induce rapid phosphorylation of MAP kinase and Akt in PC12 cells, whereas in PC84 cells, MAP kinase was phosphorylated but the phosphorylation level of Akt was very low under the serum-free condition. This finding suggested that the low expression level of p75 in PC84 cells was the reason for the low Akt activation. Because Akt is known to be activated via phosphatidylinositol (PI) 3-kinase, we treated PC12 cells with a PI3-kinase inhibitor, Wortmannin, and found these cells did not cease proliferation in the presence of NGF. Furthermore, anti-p75 neutralizing antibody reduced NGF-induced phosphorylation of Akt in PC12 cells under the serum-free condition. Because we had already shown that PC12 cells treated with anti-p75 neutralizing antibody did not cease proliferation in the presence of NGF, these results suggest that NGF activates Akt via p75, which is necessary for the NGF-induced growth arrest of PC12 cells.  相似文献   
106.
Ten patients with SSPE were surveyed during the last 4 years from the viewpoint of clinical safety for use of ribavirin therapy. Although effectiveness varied among cases, they were all treated safely with intraventricular ribavirin. This study suggests that treatment is safe and well-tolerated.  相似文献   
107.
108.
109.
BACKGROUND: The relationship between occupational class and exposure to job stressors among employed men and women in Japan remains unclear. METHODS: Data of 16,444 men and 3,078 women were analyzed. The information was obtained from answers to a questionnaire distributed among employees of nine companies in Japan between 1996 and 1998 (average response rate, 85%). The International Standardized Classification of Occupations was used to classify respondents into eight occupational categories. The Job Content Questionnaire was used to measure job demands, job control, worksite support, and job insecurity. The associations between occupational class and job stressors, as well as job strain, were examined controlling for age, education, marital status, chronic medical condition, and personality traits, such as neuroticism and extraversion. RESULTS: Men and women in high-class occupations (e.g., managers and professionals) had significantly greater job control, while job demands and worksite social support were not greatly different among occupations. A clear occupational class gradient in job insecurity was observed in women. A greater prevalence of high job strain was observed in low-class occupations compared to high-class occupations in both men and women. The occupational class gradient in job strain was greater for women. These patterns did not change after controlling for other covariates. CONCLUSION: The present study suggests an occupational class gradient in job strain for employed men and women in Japan. Japanese women workers may have a greater occupational class gradient in job strain and job insecurity than men.  相似文献   
110.
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