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11.
We have found that steroid bolus withdrawal prior to graft reperfusion increased the incidence of acute cellular rejection (ACR). This study aims to clarify how initial steroid bolus (ISB) injection at reperfusion influences the kinetics of CD8(+) alloreactive immune responses immediately after living donor liver transplantation (LDLT). A total of 49 hepatitis C virus (HCV)-infected recipients were classified into 3 groups according to hierarchical clustering by preoperative CD8(+)CD45 isoforms. The naive T cell proportion was considerably higher in Group I than in Groups II and III, whereas Group II recipients had the highest effector memory (EM) T cells and Group III the highest effector T cells. The frequency of ACR was significantly higher in recipients without ISB than in those with ISB. In particular, the ACR rates were the highest in Group II without ISB. Following ISB, the proportion of effector T cells was promptly upregulated within 6 hours after graft reperfusion, simultaneously with the upregulation of CD27(-)CD28(-) subsets, interferon-gamma (IFN-gamma), tumor necrosis factor-alpha and perforin expression, which significantly correlated with increasing interleukin (IL)-12 receptor beta 1 cells. These were then downregulated to below preoperative levels by tacrolimus (Tac) administered at 24 hours. These changes did not occur in the absence of ISB. In Group II without ISB, the downregulation of IL-12Rbeta1(+) cells was the greatest, consistent with the highest rates of ACR and mortality (60%). In conclusion, ISB must be done in place, especially in Group II with preexisting high EM T cells, to enable the development of early allograft acceptance.  相似文献   
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Objective Self-expandable metallic stent (EMS) placement has been the first choice for dysphagia because of the certainty over its safety, low invasiveness, and immediate efficacy. However, there still remain some problems in relation to the EMS placement site and anticancer therapies before and after EMS placement. Methods: Consecutive 78 patients in whom EMS was placed due to the unresectable malignant stricture in the esophagus or cardia from July 1995 to August 2003 in our department were studied. Results: Gastroesophageal reflux was found in 5 of 8 patients after placement of conventional EMS for the stricture in the gastroesophageal junction. Meanwhile, acid and bile reflux into the esophagus were not detected by pH and bilirubin monitoring, respectively, in 6 patients after placement of the EMS with an anti-reflux mechanism for the stricture in the gastroesophageal junction. The median survival period of all patients after EMS placement was 123 days. The median survival period of 7 patients with radiotherapy only after EMS placement was 138 days and that of 17 patients with radiotherapy before EMS placement was 60 days, which was shorter than that of the former (p<0.05). On the other hand, the median survival period after hospital admission due to dysphagia of these 7 patients was longer than that of 17 patients with radiotherapy only before EMS placement, although, the difference was not significant. Conclusion: EMS with an antireflux mechanism is not commercially available in Japan and approval is urgently required. The indication of radiotherapy associated with EMS placement is to be studied further.  相似文献   
14.
A series of 8 rat and 16 mouse invasive bladder carcinomas were investigated for the presence of silverstained nucleolar organizer regions (AgNORs) to clarify whether this parameter is applicable to the estimation of their invasive character. With regard to number of AgNORs per cell, neither rat nor mouse carcinomas showed any difference between invasive and noninvasive sites within the same tumor. However, the frequency of cancer cells bearing bizarre dots, irregular in size and shape, was significantly higher at sites of actual invasion. Quantitative data generated using an image analyzer revealed significantly lower values for NOR roundness and significantly larger NOR size in invasive sites than in noninvasive sites in all groups. Double staining for the proliferation marker proliferating cell nuclear antigen (PCNA) and AgNORs was performed on eight rat carcinomas and a close correlation between the two was confirmed. Thus the number of AgNORs in PCNA-positive cells was significantly greater than in PCNA-negative cells. Furthermore, a particularly strong correlation was observed for incidences of PCNA-positive cells and bizarre dots (P<0.01). The quantitative data also demonstrated significant differences in size and shape of dots. It is concluded that AgNORs have diagnostic value for the invasive character of bladder carcinomas.  相似文献   
15.
Although the cause varies widely, we recently experienced a case of constrictive pericarditis of which cause seemed to be traumatic as described below. The patient was a 62-year-old man having a history of epigastric trauma about 20 years ago. Since then, palpitation appeared and he was recently hospitalized in our department for the purpose of receiving an operation under the diagnosis of constrictive pericarditis. At operation, a hematoma was found in the pericardial region, which was considered to have been caused by trauma in the past. Less reports have so far been available concerning trauma-induced constrictive pericarditis and this case thus seemed to be of rarity as well.  相似文献   
16.
In order to treat fistulated esophageal cancer using a flexible stent, a covered flexible stent was constructed by wrapping a nitinol stent with a thin sheet of Gore-Tex, preserving the stents original advantages of flexibility and a low-profile introducer system. This stent was used to perform standard radiotherapy in a case of fistulated esophageal cancer.  相似文献   
17.
To study some of the factors relating to the care of mothers and newborns in an inner-city hospital, three sources of information were reviewed: an obstetric database including information on prenatal care and perinatal mortality, a database of all admissions to the hospital neonatal intensive care unit over the past 5 years, and a detailed questionnaire concerning attitudes and behaviors of recently delivered women. While analyses from these hospital-based data are not conclusive, the results add evidence for the following propositions: 1) Optimal prenatal care is infrequently obtained by mothers delivering at inner-city hospitals. Lack of prenatal care is clearly associated with increased perinatal mortality. While the need for prenatal care is appreciated by 98% of the mothers in this sample, the most frequent reasons why prenatal care is not obtained earlier or more frequently involve knowledge about and access to prenatal care. 2) Inner-city mothers, in general, manifest attitudes and behaviors that promote the welfare of their pregnancies and newborns. These attitudes and behaviors are in stark contrast to those that are frequently attributed to inner-city women by the media. 3) Acute perinatal medical and nursing care are perceived by many postpartum women as suboptimal, particularly in terms of the lack of respect shown to patients by nurses and doctors. 4) Improved acute obstetric and neonatal care improves perinatal morbidity and mortality of infants delivered at inner-city hospitals.  相似文献   
18.
Aneurysms of the posterior cerebral artery: report of ten cases   总被引:3,自引:0,他引:3  
Ten cases of posterior cerebral artery (PCA) aneurysm are presented. There were 13 aneurysms in the 10 patients: 6 saccular, 5 fusiform, 1 broad-based, and 1 giant fusiform serpentine aneurysm. Eight patients underwent operation: clipping for 2 saccular aneurysms, trapping for 1 saccular and 3 fusiform aneurysms, and coating for 2 fusiform or broad-based aneurysms. Microsurgical cerebral revascularization techniques were attempted in 2 cases: after a fusiform aneurysm had been excised, end-to-end anastomosis of the residual two ends of the PCA was performed and, after a giant serpentine aneurysm had been trapped, the superficial temporal artery was anastomosed transcortically to the distal PCA. Two patients died before operation because of rebleeding and vasospasm. Postoperative neurological deficits include contralateral hemiparesis, homonymous hemianopsia, hemihypesthesia, and ipsilateral 3rd nerve palsy. Our results suggest that, despite the good collateral circulation of the PCA, some ischemic events may occur after trapping procedures and that cerebral revascularization techniques may have some benefit in the treatment of unclippable aneurysms in this region.  相似文献   
19.
Modifying potentials of various chemicals on tumor development were investigated in a wide-spectrum organ carcinogenesis model using male F344/DuCrj rats. The animals were treated with N-nitroso-diethylamine (100 mg/kg body weight, ip, single injection at the commencement of the study), N-methyl-N-nitrosourea (20 mg/kg body weight, ip, 4 times during weeks 1 and 2) and N-bis(2-hydroxypropyl)nitrosamine (0.1% in drinking water, during weeks 3 and 4) for multi-organ initiation and then were given one of 14 test chemicals including 6 hepatocarcinogens, 7 non-hepatocarcinogens and 1 non-carcinogen, or basal diet for 16 weeks. All rats were killed at the end of week 20, and the major organs were carefully examined for preneoplastic and neoplastic lesions. Immunohistochemical demonstration of glutathione S -transferase-positivc foci was also used for quantitative assessment of liver preneoplastic lesion development. Modifying effects were shown for 11 out of 14 test agents in the liver, forestomach, glandular stomach, lung, urinary bladder or thyroid, 7 of them targeting more than two organs. This was the first demonstration to our knowledge that cloflbrate possesses enhancing potential for urinary bladder carcinogenesis and an inhibiting effect on thyroid carcinogenesis. Caprolactam showed no effect in any organ, in agreement with its established inactivity. The results indicated that the system could be reliably applied as a medium-term multiple organ bioassay for assessment of the modification potential of test agents in unknown target sites.  相似文献   
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