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101.
BACKGROUND: Pain induces a variety of physiological responses, many of which are mediated by the sympathetic nervous system. Among these are a reduction in peripheral blood flow and evaporative cutaneous water loss (sweating). We therefore tested the hypothesis that adequate sedation obliterates the normal pain-induced reduction in peripheral blood flow and an increase in evaporative water loss. METHODS: We studied eight volunteers. Two different painful stimuli were randomly applied: 1) electrical pulp stimulation (200 microamperes) and 2) electrical pain stimulation on the right upper thigh (80 mA). Conscious sedating was controlled by propofol infusion titrated to a Bispectral Index near 80, or near 60. RESULTS: At each stimulation, peripheral blood flow detected by laser Doppler decreased without any relation to the level of consciousness (by Bispectral Index). On the other hand, although the psychogenic perspiration rate increased significantly at alert level, during BIS 80 or 60 level, the increase was not significant. CONCLUSION: Peripheral blood flow reacts most to pain stimulation during intravenous sedation.  相似文献   
102.
BACKGROUND: The risk of occupational exposure to waste anesthetic gases still remains during inhaled induction. In this study we investigated how much we were occupationally exposed to anesthetic gases during induction period. METHODS: Twenty-six adult patients were induced with sevoflurane 5% using a face mask for three minutes and maintained with sevoflurane 1% after end-tracheal intubations (IH-Group). Twenty-two adult patients were induced with intravenous anesthetics and maintained with sevoflurane 1% after end-tracheal intubations(IV-Group). The concentration of sevoflurane was measured by Multi-gas Monitor 1302 (Bruel & Kjaer: Denmark) every 70 seconds. Sample gas was suctioned from breathing zone of anesthesiologists. All of our operating rooms are equipped with waste gas scavenging system. RESULTS: The peak concentration of sevoflurane is significantly higher in IH-Group (15.91 +/- 22.64 ppm) compared with IV-group (0.36 +/- 0.25 ppm). The period when sevoflurane concentration exceeded 0.5 ppm is significantly longer IH-Group (18.55 +/- 10.51 min.) compared to IV-Group (1.92 +/- 4.56 min.). CONCLUSION: The induction with intravenous anesthetics is a better method in order to reduce occupational exposure of anesthesiologists to anesthetic gases.  相似文献   
103.
The significance of hepatic arterial infusion chemotherapy for unresectable liver metastases from colorectal cancer was evaluated in 50 patients, who received either of the following regimens: 1 shot 5-FU + epirubicin + MMC (FAM group); hepatic arterial infusion of 5-FU for 2 hours + MMC (MF group); hepatic arterial infusion of 5-FU for 2 hours (5-FU group). There were no differences in the clinicopathological backgrounds of the patients among the groups. The mean survival time was 10.3 months, 16.0 months and 16.2 months in the FAM, MF and 5-FU groups. The effective percentages were 0%, 40% and 31% in the FAM, MF and 5-FU groups and the survival time of the effective cases was 18.1 months and 21.8 months in the MF and 5-FU groups. The MF group and 5-FU group showed significant improvement in prognosis. Concerning side effects, myelo-suppression and gastrointestinal toxicity appeared frequently in the MF group. In conclusion, 2-hour continuous hepatic arterial infusion with low-dose 5-FU for unresectable liver metastases from colorectal cancer may be helpful for improvement of prognosis.  相似文献   
104.
BACKGROUND: The demonstration of the monoclonality of immunoglobulin heavy chain (IgH) gene rearrangement is an indispensable method for the diagnosis of B-cell lymphoma as well as histocytochemical analysis. For the detection of IgH gene rearrangement, the extraction of DNA from a homogenous cell population is necessary. Recently, the laser capture microdissection (LCM) technique was shown to isolate specific cells from histopathologic specimens for molecular analysis. However, to the authors' knowledge the applicability of LCM to cytologic specimens has not yet been well established. METHODS: Using LCM, a homogenous population of B-cell lymphoma cells as both histologic sections and cytologic specimens was captured, and genomic DNA was extracted from the captured cells. IgH gene rearrangement was analyzed by the polymerase chain reaction (PCR)-based single-strand conformational polymorphism (SSCP) method. RESULTS: Genomic DNAs were extracted successfully from ethanol-fixed cytologic specimens, but cells were not captured from air-dried specimens. Using PCR-SSCP analysis, the monoclonality of the IgH gene rearrangement was detected in five cases of tissue sections among nine analyzed cases of malignant lymphoma diagnosed immunohistochemically. However, analysis of the cytologic specimens with LCM demonstrated the monoclonality of the IgH gene rearrangement in seven cases of lymphoma. CONCLUSIONS: The results of the current study suggest that the novel application of LCM to cytologic specimens occasionally exhibits high sensitivity for the detection of IgH gene rearrangement monoclonality compared with the use of histologic sections.  相似文献   
105.
106.
Shortening the diagnostic delay from the onset of symptoms to the final diagnosis leads to early cancer detection and a reduced incidence of advanced cases. To analyze factors contributing to delays in the diagnosis of oral cancer, information was collected from the medical charts of 152 consecutive patients with oral squamous cell carcinoma, and factors associated with diagnostic delay were examined retrospectively. No characteristic was significantly associated with delay caused by patients. Referral by a non-initial professional, initial visit to a dentist, T1 cancer, and the presence of an ulcerative lesion were significantly associated with delay caused by the initial professionals. Patients with N0 were significantly associated with diagnostic delay caused by the final professional. These results re-emphasize the important role of the initial professional, particularly the dentist, and the diagnostic difficulty posed by ulcerative lesions and small-sized or early-stage oral cancer.  相似文献   
107.
It is known that autonomic nervous activities change in correspondence with sleep stages. However, the characteristics of continuous fluctuations in nocturnal autonomic nerve tone have not been clarified in detail. The study aimed to determine the possible correlation between the electroencephalogram (EEG) and autonomic nervous activities, and to clarify in detail the nocturnal fluctuations in autonomic nerve activities. Overnight EEGs and electrocardiograms of seven healthy males were obtained. These EEGs were analyzed by fast Fourier transformation algorithm to extract delta, sigma and beta power. Heart rate and heart rate variability (HRV) were calculated in consecutive 5-min epochs. The HRV indices of low frequency (LF), high frequency (HF) and LF/HF ratio were calculated from the spectral analysis of R-R intervals. The sleep stages were manually scored according to Rechtschaffen and Kales' criteria. Low frequency and LF/HF were significantly lower during non-rapid eye movement (NREM) than REM, and were lower in stages 3 and 4 than in stages 1 and 2. Furthermore, delta EEG showed inverse correlations with LF (r = - 0.44, P < 0.001) and LF/HF (r = - 0.41, P < 0.001). In contrast, HF differed neither between REM and NREM nor among NREM sleep stages. Detailed analysis revealed that correlation was evident from the first to third NREM, but not in the fourth and fifth NREM. Delta EEG power showed negative correlations with LF and LF/HF, suggesting that sympathetic nervous activities continuously fluctuate in accordance with sleep deepening and lightening.  相似文献   
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110.
The occurrence of a collision tumor in the stomach, consisting of adenocarcinoma and malignant lymphoma, is extremely rare. We report herein the case of a patient who had undergone a pancreatoduodenectomy for bile duct cancer 5 year earlier, in whom an ulcerating tumor of the remnant stomach developed and grew rapidly within 5 months. Surgical exploration revealed a tumor in the remnant stomach, multiple liver metastases, and multiple lymph node metastases. Total resection of the remnant stomach was performed, and pathological examination revealed a collision tumor consisting of adenocarcinoma and malignant lymphoma. The patient died of liver metastases and lymph node metastases 7 months after his second operation. The coexistence of both adenocarcinoma and malignant lymphoma of the remnant stomach and the etiology of this unusual combination, never previously reported, is discussed. Received: December 20, 1999 / Accepted: November 20, 2000  相似文献   
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