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31.
We previously reported that the Guardian Bio-Threat Alert (BTA) system could detect (detection limit: about 0.1 μg/ml) staphylococcal enterotoxin B (SEB), botulinum toxins (BTX) A and B, and ricin, with no interference by white-powdered materials or colored matrices. In this study, the capability of the BTA system was further assessed. With 10 min of preheating at 60°C, all toxins could be detected, but with preheating at 80°C, BTX A and B and ricin became undetectable. About 20% SEB could be detected after heating at 80°C, but this detection ability was completely removed after heating at 100°C. The effects of chemicals usually used for decontamination, such as sodium hypochlorite, hydrogen peroxide, formaldehyde, and sodium nitrite, on the detectability of SEB, BTX A, or ricin in the BTA system were also tested. The concentrations giving 50% line intensity for SEB, BTX A, and ricin were 3.1, 11, and 15 μM for sodium hypochlorite and 88, 210, and 60 mM for formaldehyde, respectively. The addition of hydrogen peroxide or sodium nitrite did not decrease the detectability even when used at high concentrations.  相似文献   
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Background: A major effect of general anesthesia is lack of response in the presence of a noxious stimulus. Anesthetic depression of spinal sensory neuronal responses to noxious stimuli is likely to contribute to that essential general anesthetic action. The authors tested the hypothesis that [gamma]-aminobutyric acid receptor type A (GABAA) and strychnine-sensitive glycine receptor systems mediate halothane depression of spinal sensory neuronal responses to noxious stimuli.

Methods: Extracellular activity of single spinal dorsal horn wide dynamic range (WDR) neurons was recorded in decerebrate, spinal cord transected rats. Neuronal responses to noxious (thermal and mechanical) and nonnoxious stimuli were examined in the drug-free state. Subsequently, cumulative doses (0.1-2.0 mg/kg) of bicuculline (GABAA antagonist) or strychnine (glycine antagonist) were administered intravenously in the absence or presence of 1 minimum alveolar concentration (MAC) of halothane.

Results: Halothane, 1.1%, depressed the response of WDR neurons to both forms of noxious stimuli. Antagonists, by themselves, had no effect on noxiously evoked activity. However, bicuculline and strychnine (maximum cumulative dose, 2.0 mg/kg) partially but significantly reversed the halothane depression of noxiously evoked activity. Similar results were seen with most, but not all, forms of nonnoxiously evoked activity. In the absence of halothane, strychnine significantly increased neuronal responses to low threshold receptive field brushing.  相似文献   

34.
Skull metastasis of thyroid carcinoma is rare. The majority of skull metastases of thyroid carcinoma are of the follicular subtype, rather than thyroid papillary carcinoma. In this report, a 55-year-old woman with skull metastasis from thyroid papillary carcinoma is presented. The metastatic lesion of the skull was hypervascular and osteolytic, and the bleeding was profuse during resection. There have been only four reports of skull metastasis from thyroid papillary carcinoma. The mean period from the initial diagnosis of thyroid carcinoma until the detection of skull metastasis is 23.3 years, whereas in this patient, it was about 2 years. Therefore, in the clinical course of thyroid papillary carcinoma, skull metastasis should be considered, and the patient should be meticulously followed up.  相似文献   
35.
1. This study was undertaken to evaluate the preventive effects of locally administered argatroban, a competitive inhibitor of thrombin-induced platelet activation, on restenosis after balloon angioplasty. 2. A hydrogel-coated balloon catheter was immersed three times in argatroban/saline solution (1 mg/mL) for 60 s, inflated to a pressure of 606 kPa and left in the rabbit common carotid artery for 1 min. The same procedure was performed, without drug, as a control. The pharmacokinetics of delivered argatroban in the arterial wall were assessed using [14C]-argatroban. Platelet deposition 2h after balloon injury was quantified by fluorescence studies using antiplatelet antibody. Vascular smooth muscle cell (VSMC) proliferation 3 days after balloon injury was assessed by immunohistochemical staining for proliferative cell nuclear antigen (PCNA). In a clinical study, we divided 50 elective patients into two groups: argatroban and control. 3. In the experimental study, the mean quantities of argatroban at 0, 2 and 6 h after deflation wer. 24.63, 0.49 and 0.11 nmol/g wet weight of artery, respectively. Argatroban was undetected 24 h after deflation. Two hours after deflation, argatroban-treated arteries showed less platelet adhesion than saline-treated controls. The mean number of PCNA-positive cells was 16.9 and 43.8% in the argatroban and control groups, respectively (P < 0.01). In the clinical study, the mean late gain loss was 8.2 and 27.3% in the argatroban and control groups, respectively (P < 0.05). The mean late restenosis rate was 11.1 and 41.4% in the argatroban and control groups, respectively (P<0.05). 4. These data suggest that blood coagulation plays a significant role in VSMC proliferation after balloon injury and that locally administered argatroban using hydrogel-coated balloon catheter may prevent post-percutaneous transluminal coronary angioplast. restenosis.  相似文献   
36.
We describe our technique for performing direct thoracoscopic closure of a congenital partial pericardial defect, which was successfully employed in a 15-year-old boy. This is the first such report of a procedure that is noninvasive and may therefore become the treatment of choice for patients with a small congenital pericardial defect.  相似文献   
37.
A 52-year-old woman who had had 6 months of chemotherapy using mitomycin C and cisplatin for cervical cancer presented with hemolytic uremic syndrome. Conventional plasmapheresis using whole-plasma fraction was ineffective. However, plasmapheresis using the cryosupernatant fraction dramatically improved symptoms of hemolytic anemia and thrombocytopenia in this case. The activity of factor VIII in the cryosupernatant fraction of plasma as a replacement fluid decreased after removal of cryoprecipitate, indicating effective removal of von Willebrand factor. The pathogenesis of her hemolytic uremic syndrome may have been associated with von Willebrand factor multimers contained in the cryoprecipitate of plasma. Similar use of the cryosupernatant fraction of plasma could not be found in other reports of cases of hemolytic uremic syndrome. Plasmapheresis using the cryosupernatant fraction of plasma may improve refractory hemolytic uremic syndrome.  相似文献   
38.
Background and Objective: To further understand the precise process of the tumor cell degeneration after photodynamic therapy (PDT), laser hyperthermic therapy (LH), and combined treatments using an Nd:YAG laser. It is important to examine initial morphological alteration of tumor cells after these treatments. Study Design/Materials and Methods: In this study, nude mice bearing HeLa cell tumors were treated with PDT, LH, and combined treatments of the two. Tumor tissues obtained immediately after these treatments were analyzed using electron microscopy and morphometry. Results: In the combined treatments, which produced more severe effects on tumor cells, morphological features of apoptosis such as cytoplasmic condensation, blebs, and apoptotic bodies appeared in the cells, although the typical alteration in the nuclear chromatin was not seen. Conclusion: Cytoplasmic alterations may proceed more rapidly than nuclear alterations in the cellular degeneration induced by the single or combined treatments of PDT and LH.  相似文献   
39.
A rare case of jejunal carcinoma coexisting with adenoma, situated 120 cm distal to the ligament of Treitz in a 53 year old male, is reported herein. We also review cases of adenoma and carcinoma in the jejunum and ileum from the Japanese literature, and discuss the histogenesis of carcinoma of the jejunum and ileum.  相似文献   
40.
We report herein the case of a 77-year-old man with a left ventricular tumor originating from the papillary muscle of the left ventricular wall, in whom a successful tumor resection with mitral valve replacement was performed. The pathological diagnosis of the tumor was confirmed as cardiac fibroma. His postoperative course was uneventful and he is currently well with no signs of recurrence 2 years after surgery.  相似文献   
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