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31.
In order to investigate the possibility that the theory of two-stage carcinogenesis can be applied to neurogenic carcinogenesis, we analyzed the promoting effect of 12-O-tetradecanoylphorbol-13-acetate (TPA) on the in vitro malignant transformation of fetal rat brain cells exposed in utero to ethylnitrosourea (ENU). Rat brain cells were transferred to a cultured system at 72 h after a single pulse of ENU (50 mg/kg body weight) to pregnant SD-JCL rats on the 18th day of gestation. The positive findings of glial fibrillary acidic protein and S-100 protein in primary cultured cells by the analysis of immunohistochemistry revealed the neuroglial origin of transformed cells. These cells were divided into 12 groups and were treated twice per week with or without TPA at concentrations from 0.1 to 50.0 ng/ml. From the results of cellular morphology, Concanavalin A agglutinability, colony forming capacity in semisolid soft agar, and tumorigenicity in vivo, malignant transformation of fetal rat brain cells appeared earlier in the ENU group treated with TPA than in the untreated ENU group. On the basis of these observations, it is suggested that TPA might be effective as a tumor promoter on ENU-induced neurogenic carcinogenesis.  相似文献   
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33.
OBJECTIVE: Neuropsychiatric disturbances are common and burdensome symptoms of dementia. Assessment and measurement of neuropsychiatric disturbances are indispensable to the management of patients with dementia. Neuropsychiatric Inventory (NPI) is a comprehensive assessment tool that evaluates psychiatric symptoms in dementia. We translated the NPI-Caregiver Distress Scale part of NPI (NPI-D) and NPI-Brief Questionnaire Form (NPI-Q) into Japanese and examined their validity and reliability. SUBJECTS AND METHODS: The subjects were 152 demented patients and the caregivers who lived with them. These patients consisted of 76 women and 76 men; their mean age was 73.9 +/- 7.8 (S.D.; range: 49 to 93) years. Their caregivers consisted of 46 men and 106 women; their mean age was 65.0 +/- 11.4 (S.D.; range: 35 to 90) years. The Mini-Mental State Examination (MMSE) was conducted with all patients and NPI-Q, NPI, NPI-D, and the Zarit caregiver burden interview (ZBI) were conducted with all caregivers. We examined validity of NPI-D by comparing its score with the MMSE and ZBI scores, and the validity of NPI-Q by comparing its score with the NPI and NPI-D scores. In order to evaluate test-retest reliability, NPI-D was re-adopted to 30 randomly selected caregivers by a different examiner one month later and NPI-Q was re-executed by 27 randomly selected caregivers one day later. RESULTS: Total NPI-D score was significantly correlated with ZBI (rs = 0.59, p < 0.01). Test-retest reliability of NPI-D was adequate (ri = 0.47, p < 0.01). Total NPI-Q severity score and distress score were strongly correlated with NPI (r = 0.77, p < 0.01) and NPI-D (r = 0.80, p < 0.01) scores, respectively. Test-retest reliability of the scores of NPI-Q was acceptably high (the severity score; ri = 0.81, p < 0.01, the distress score; ri = 0.80, p < 0.01). CONCLUSION: The Japanese version of NPI-D and NPI-Q demonstrated sufficient validity and reliability as well as the original version of them. These are useful tools for evaluating psychiatric symptoms in demented patients and their caregivers' distress attributable to these symptoms.  相似文献   
34.
We present a 70‐year‐old man who had two episodes of melena during the preceding 8‐year period. He had a Dieulafoy‐like lesion in a diverticulum in the third portion of the duodenum. While emergency endoscopy revealed neither apparent blood nor clots around the diverticular orifice, there was a non‐bleeding vessel in the fundus of the diverticulum. The vessel ceased bleeding after argon plasma coagulation and, since then, the patient has not experienced bleeding. In cases of gastrointestinal bleeding of obscure origin, duodenal diverticulum should be considered as a possible source of bleeding, even when endoscopy discloses no apparent bleeding.  相似文献   
35.
The excitatory responses of deflationary slowly adapting pulmonary stretch receptor (SAR) activity to lung deflation ranging from approximately -15 to -25 cm of H(2)O for approximately 5 s were examined before and after administration of flecainide, a Na(+) channel blocker, and K(+) channel blockers, such as 4-aminopyridine (4-AP) and tetraethylammonium (TEA). The experiments were performed in anesthetized, artificially ventilated rats after unilateral vagotomy. The deflationary SARs increased their activity during lung deflation and its effect became more pronounced by increasing the degree of negative pressure. During lung deflation the average values for the deflationary SAR adaptation index (AI) were below 40%. Intravenous administration of veratridine (50 microg/kg), an Na(+) channel opener, stimulated deflationary SAR activity: one maintained excitatory activity mainly during deflation and the other receptors showed a tonic discharge during both deflation and inflation. Despite the difference in deflationary SAR firing patterns after veratridine administration, flecainide treatment (6.0 mg/kg) blocked veratridine-induced deflationary SAR stimulation and also caused strong inhibition of the excitatory responses of deflationary SARs to lung deflation. Under these conditions, the average values for deflationary SAR AI were over 90%. The responses of deflationary SARs and deflationary SAR AI to lung deflation were not significantly altered by pretreatment with either 4-AP (0.7 and 2.0 mg/kg) or TEA (2.0 and 6.0 mg/kg). These results suggest that the excitatory effect of lung deflation on deflationary SAR activity is mediated by the activation of flecainide-sensitive Na(+) channels on the nerve terminals of deflationary SARs.  相似文献   
36.
Purpose Several case reports indicate critical respiratory complications in relation to the double-lumen endobronchial tube (DLT). A prospective survey for the airway problems in using the DLT is presented. Methods One hundred adult patients undergoing thoracotomy for lung cancer were investigated. Tube malposition and airway obstruction were searched using a fiber-optic scope. The endobronchial cuff was positioned just below the trachcal carina while the trachea was intubated with a DLT (Rüsch). The distances of displacement, from the tracheal carina to the bronchial cuff, were measured during anesthesia using an epidural catheter, which had marks every 5 mm. The distances for correcting the tube position were measured at both the bronchial cuff and the level of the teethPaO2,PaCO2 andSPO2 were also measured. Results Malposition (displacement over 5 mm from the correct position) was found in 42 patients, and 40 of them were in a withdrawal direction, occurring at the postural change and during one-lung ventilation, especially during manipulation of the lung hilum. Correcting distances at the level of the teeth were 15.3–3-times longer than those at the bronchial cuff. Airway deformities and gradual withdrawal of the bronchial cuff were found in association with surgical manipulation. Obstruction occurred at the tips of the tracheal tube in four patients and the bronchial tube in six patients, and at the tip of both in two patients. Hypoxemia (PaO2<60 mmHg) occurred in four patients and hypercapnea (PaCO2>60 mm Hg) in two patients. Conclusion Most of the DLT obstructions were associated with withdrawal malposition. Great attention to DLT displacement and airway deformity is advised.  相似文献   
37.
This report concerns a notable case of progressive supranuclear palsy exhibiting asymmetric dentate nucleus and thalamic degeneration with numerous torpedoes. The neuronal loss in the ventral lateral nucleus of the thalamus was predominant on the right side, while in the cerebellum, a quantitative study revealed the contralateral predominance of the neuronal loss in the dentate nuclei and torpedo formation, with preserved Purkinje cells. The abnormal tau-protein-related profiles in the two nuclei did not show any laterality in their distribution, indicating that the dentatothalamic tract may have been affected in a non-specific way in this case. In addition, the fact that the prominent sites of torpedo formation and loss of dentate nucleus neurons are identical supports the hypothesis that the torpedoes may be formed in association with neuronal loss in the dentate nucleus because of a plausible metabolic change in Purkinje cells through synaptic detachment of their axon terminals. Received: 4 January 1996 / Revised: 27 March 1996 / Accepted: 5 April 1996  相似文献   
38.
K Matsumoto 《Nephron》1990,55(3):300-305
We have investigated the effect of recombinant tumor necrosis factor (r-TNF) on the release of interleukin-1 (IL-1) in glomerular cultures from rats with an accelerated autologous form of nephrotoxic serum nephritis (NTSN). Freshly isolated glomeruli from the NTSN rats were incubated for 24 h in the presence of r-TNF. When the glomeruli were activated by r-TNF substantial amounts of IL-1 could be detected in the supernatants as measured by the mouse thymocyte assay. The r-TNF-induced IL-1 activity was significantly higher in rats with NTSN than those in normal controls and the other control group, consisting of preimmunized rats (rabbit IgG), then given normal rabbit globulin instead of NTS. To avoid the effect of prostaglandins on the IL-1 assay, we cultured the glomeruli with addition of indomethacin and assayed IL-1 activity in the culture supernatants. This cyclooxygenase inhibitor augmented r-TNF-induced IL-1 production. Our data suggest that r-TNF can serve as a potent stimulator of IL-1 synthesis in glomerular cultures from rats with NTSN.  相似文献   
39.
The seven metabolites of (+)-dehydroabietic acid (DHA) were newly isolated from rabbit urine by liquid chromatography. On the basis of chemical and spectral data their structures were established to be (15S)-8,11.13-abietatrien-16,18-dioic acid, 2 alpha-hydroxy-8,11,13,15-abietatetraen-18-oic acid, (15R)-15,16-dihydroxy-8,11,13-abietatrien-18-oic acid, 2 beta,15-dihydroxy-8,11,13-abietatrien-18-oic acid, (15S)-2 beta,16-dihydroxy-8,11,13-abietatrien-18-oic acid, 2 alpha,15-dihydroxy-8,11,13-abietatrien-18-oic acid, and (15S)-2 alpha,16-dihydroxy-8,11,13-abietatrien-18-oic acid. The possible hydroxylation routes of DHA in rabbits and the difference between the metabolism of DHA in microorganisms and that in rabbits are discussed.  相似文献   
40.
A transjugular snare technique was used to retrieve a stretched, residual mechanical detachable coil which extended from the cavernous sinus to the femoral vein, obliterating the transpetrosal route for further embolisation. The coil was snared by a microguidewire. Our new technique is described in this paper. Received: 19 April 1995 Accepted: 31 July 1995  相似文献   
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