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31.
Pain-related somatosensory evoked potentials (pain SEPs) following CO2 laser stimulation were examined in 30 patients with peripheral neuropathies, and the results were compared with clinical sensory findings. Pain SEP findings showed a significant correlation with the clinical impairment of pain sensation, but not with the impairment of deep sensations. In contrast, conventional electrically-stimulated SEPs (electric SEPs) showed a significant correlation with deep sensations, but not with the impairment of pain sensation. Examinations of both pain SEPs and electric SEPs, therefore, are considered to be very useful to evaluate physiological functions of sensory nerves in patients with peripheral neuropathies.  相似文献   
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33.
BACKGROUND: Cytomegalovirus (CMV) diseases commonly occur in allograft recipients in the early post-transplant period. However, factors responsible for the high incidence of CMV diseases during this period are not yet fully defined. METHODS: Wistar-Furth (WF; RT-1(u)) rats were inoculated with 10(4) plaque-forming units (PFU) of rat CMV (RCMV) intraperitoneally, and then transplanted with allogeneic lungs from Dark Agouti (DA; RT-1avl) rats or stimulated with 10(7) mitomycin C-treated spleen cells from DA rats by daily sub-cutaneous injections for 2 weeks. No immunosuppressive agent was used. Naive WF rats and WF rats grafted with syngeneic lungs or cells were used as controls. The level of RCMV replication in rats was assessed by infectious virus titers in tissues. RESULTS: The virus titers in salivary glands of allogeneic and syngeneic lung graft recipients were significantly higher than in naive WF rats. The level of RCMV replication in rats stimulated with allogeneic spleen cells was significantly higher than in the syngeneic recipient rats: virus titers in the salivary gland of allogeneic and syngeneic recipients reached 4.61 +/- 0.33 and 4.00 +/- 0.37 log(10) PFU/g tissue, respectively, at 14 days post-infection (p = 0.015). The augmented viral replication in allogeneic recipients was confirmed by an increase in the number of RCMV antigen-positive macrophages present in tissue sections of the salivary gland. CONCLUSIONS: Acute lung allograft rejection and allogeneic spleen cell stimulation enhance CMV replication in the salivary gland of rats. Various responses to allogeneic antigens occurring in the process of acute allograft rejection could be risk factors for post-transplant CMV replication and infection.  相似文献   
34.
The radiologic and histologic findings are presented of the resection of 14 small hepatocellular carcinomas (HCC), less than 2 cm in maximum diameter, after transcatheter arterial chemoembolization (TCE) using iodized oil. The effect of TCE on small HCC depended on the morphologic type of the tumors. When no extracapsular invasion of tumor cells occurred, TCE was extremely effective against encapsulated tumors. However, in nine of the 14 resected specimens, viable tumor cells remained in or around the tumor. The authors suggest that small HCC are not always curable with TCE alone and that a multi-disciplinary approach is necessary for patients with small HCC.  相似文献   
35.
1. The present study was undertaken to examine whether or not 5-HT-induced inositol monophosphate (IP-1) accumulation in human platelets is mediated by 5-HT-2 receptors and to assess 5-HT-2 receptor function as measured by 5-HT-stimulated IP-1 accumulation in platelets from normal controls and depressed patients before drug treatment. 2. In platelets prelabeled with 3H-myo-inositol, in Ca ion free HEPES buffer containing 10 mM LiCl, 5-HT caused a dose-dependent accumulation of IP-1 during 15 min incubation. A maximal increase in IP-1 formation was observed at 30 microM of 5-HT and its EC50 value was 4 microM. 3. Ketanserin, a selective 5-HT-2 antagonist, was a potent inhibitor of 5-HT-stimulated IP-1 accumulation with a Ki value of 12 nM, but (-)propranolol (10 microM), a 5-HT-1 antagonist, failed to block the 5-HT response. 4. The potencies of various compounds tested to inhibit 5-HT-stimulated IP-1 accumulation in human platelets correlated positively with the affinities to 5-HT-2 receptor as defined by radioligand binding in rat cerebral cortex. 5. In a group of unmedicated patients with major depressive disorder matched for age with normal control group, we found a significant increase in 5-HT (100 microM)-induced accumulation of IP-1 (150 +/- 7% of basal for depressed patients, 132 +/- 3% for controls).  相似文献   
36.
OBJECTIVE: To investigate the possibility in rats that ONO-5046 Na, a new recombinant inhibitor of neutrophil elastase, can reduce hepatic metastases induced by ischaemia-reperfusion. DESIGN: Laboratory experimental study. SETTING: Research laboratory, Japan. SUBJECTS: Male Fischer rats. INTERVENTIONS: Rats underwent 60 min of 70% partial hepatic ischaemia, after which rat colon adenocarcinoma cells (RCN-H4) were injected into the spleen. The animals were divided into two test groups and a control group. One group was given ONO-5046 Na intravenously at 10 mg/kg/hour. A second group was given a saline solution for the same period, while the controls were not made ischaemic. MAIN OUTCOME MEASURES: Three weeks after inoculation, the number of tumour nodules on the liver surface was counted. The anti-cancer effect of ONO-5046 Na was measured by monotetrazolium assay. RESULTS: Hepatic ischaemia-reperfusion increased the number of liver metastases of RCN-H4 in both clamped and unclamped hepatic lobes. ONO-5046 Na significantly inhibited this in unclamped lobes, but had no anti-cancer effect. CONCLUSION: Neutrophil elastase may have an important role in increasing haematogenous liver metastases by ischaemia-reperfusion, particularly in unclamped lobes.  相似文献   
37.
Genetic alteration in carcinoid tumors of the lung.   总被引:1,自引:0,他引:1  
Surgically resected specimens of 13 carcinoid tumors of the lung including nine typical carcinoids and four atypical carcinoids, and eight salivary gland type carcinomas (six mucoepidermoid carcinomas and two adenoid cystic carcinomas) were analyzed regarding p53 expression, loss of heterozygosity (LOH) in chromosome 3p, 9p, and K-ras mutation. The overexpression of p53 was identified in four atypical carcinoid tumors, one mucoepidermoid carcinoma, and one adenoid cystic carcinoma, however, none of typical carcinoids showed p53 immunoreactivity. LOH in 3p14 was demonstrated in three of seven informative cases in all tumors. LOH in 9p was demonstrated in two of five informative cases in all tumors. Two of three cases with LOH at 3p14 had a poor prognosis, one of which also had LOH at 9p. No mutation of the K-ras gene was observed in any of these tumors. These data thus indicate that p53 overexpression might distinguish atypical carcinoid tumors from typical tumors and might therefore be useful as an adjunct modality in the differential diagnosis of pulmonary carcinoid tumors. The presence of LOH at 3p14 or 9p may thus help to identify lung cancer patients with a poor prognosis.  相似文献   
38.
Summary Haemorrhage in regions remote from the site of following intracranial operations is rare, but they do occur. We performed supratentorial craniotomy on 639 patients between the time of introduction of computed tomography (CT) for clinical use in 1983 and June 1992; subarachnoid haemorrhage (SAH) in the posterior fossa occurred postoperatively in six of these cases. These included four patients with tumours in the sellar region, one with an arteriovenous malformation (AVM) and one who underwent superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis. The ages of the six patients ranged from 17–72 years.Haemorrhage occurred on the day of operation in one case and was detected on CT examination on the day following surgery in the remaining five cases. Of three patients with disturbance of consciousness, two underwent suboccipital craniectomy for reduction of intracranial pressure, while one received barbiturate therapy and later underwent cerebrospinal fluid (CSF) shunt surgery. No special treatment was necessary for the remaining three patients with less serious lesions. Five of the six patients ultimately recovered their pre-operative neurological status apart from the primary diseases.Factors inducing such haemorrhages seem likely to include displacement of the cerebellum by reduced CSF pressure during and after operations, and stretching and tearing of the veins and venules in the sulci of the tentorial surface of the cerebellum. Consideration should therefore be given to the maintenance of an appropriate CSF pressure during operation; this is particularly important in elderly patients and those with an atrophied cerebral cortex.  相似文献   
39.
Background :
The BTA test is a latex agglutination assay for the qualitative detection in the urine of analytes that are associated with bladder tumor. We compared the results of the BTA test with those of voided urine cytology (VUC) in patients with bladder cancer.
Methods :
A multicenter trial was performed at 6 institutions. A total of 132 patients with histologically diagnosed bladder cancer were enrolled. Urine samples were split for BTA and VUC testing.
Results :
The sensitivities of the BTA test and VUC were 57.6% and 37.9%, respectively; this difference was significant ( P < 0.001). The BTA test had much higher sensitivity for small, solitary, superficial tumors than did VUC.
Conclusion :
The BTA test is simple to perform, gives rapid results, and is far more sensitive than VUC for detection of bladder cancer. The BTA test has the potential to become an additional tool for detecting bladder cancer.  相似文献   
40.
Several reports claim that portal hypertension after living-donor liver transplantation (LDLT) adversely affects graft function, but few have assessed the impact of portal venous pressure (PVP) on graft regeneration. We divided 32 adult LDLT recipients based on mean PVP during the 1st 3 days after LDLT into a group with a PVP > or = 20 mm of Hg (H Group; n = 17), and a group with a PVP < 20 mm of Hg (L Group; n = 15). Outcome in the H Group was poorer than in the L Group (58.8 vs. 92.9% at 1 year). Peak peripheral hepatocyte growth factor (HGF) during the 1st 2 weeks was higher in the H Group (L: 1,730 pg/mL, H: 3,696 pg/mL; P < .01), whereas peak portal vascular endothelial growth factor (VEGF) level during the 1st week was higher in the L Group (L: 433 pg/mL, H: 92 pg/mL; P < .05). Graft volume (GV) / standard liver volume (SLV) was higher in the H Group (L / H, at 2, 3, and 4 weeks, and at 3 months: 1.02 / 1.24, .916 / 1.16, .98 / 1.27, and .94 / 1.29, respectively; P < .05). Peak serum aspartate aminotransferase, bilirubin levels, and international normalized ratio after LDLT were significantly higher in the H Group, as was mean ascitic fluid volume. In conclusion, early postoperative PVP elevation to 20 mm of Hg or more was associated with rapid graft hypertrophy, higher peripheral blood HGF levels, and lower portal VEGF levels; and with a poor outcome, graft dysfunction with hyperbilirubinemia, coagulopathy, and severe ascites. Adequate liver regeneration requires an adequate increase in portal venous pressure and flow reflected by clearance of HGF and elevated VEGF levels.  相似文献   
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