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BACKGROUND/AIM: The aim of this study was to gain insight into the mechanisms of microvascular dysfunction after local surgical trauma. METHODS: The effect of anti-tumor necrosis factor (TNF)-alpha antibody (Ab) on microvascular function, including arteriolar diameter response, nutritive perfusion, leukocyte-endothelial cell interaction and endothelial integrity disruption, was studied in hamster skinfold chamber preparations using intravital fluorescence microscopy. RESULTS: Directly after the surgical procedure, arteriolar diameters were found to be markedly (p < 0.05) reduced, but recovered significantly at 8 h and reached plateau levels after 24 h. Surgical trauma further induced a strong inflammatory response characterized by a significant (p < 0.05) increase in leukocyte adherence to the endothelium of postcapillary venules. This inflammatory response was associated with an increase in microvascular permeability, indicating endothelial integrity disruption. Anti-TNF-alpha Ab had no significant effect on the surgical trauma-induced arteriolar vasomotor dysfunction; however, it effectively (p < 0.05) reduced venular leukocyte adherence and attenuated the increase in microvascular permeability. CONCLUSION: Our study indicates that arteriolar constriction, leukocyte-endothelial cell interaction and endothelial macromolecular leakage have to be considered as the characteristic microvascular response after local surgical trauma. It is conceivable that TNF-alpha plays a role in mediating the inflammatory response, but not the dysfunction of vasomotor control. Copyright Copyright 1999 S.Karger AG, Basel  相似文献   
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OBJECTIVE: The number of foreigners residing in Japan has increased during the past decade. The aim of this survey was to clarify the present situation and the disadvantages in the medical care for foreigners. METHODS: In October 1997, we mailed a questionnaire to all clinics and hospitals in Chiba City. The questionnaire included questions regarding the number of foreign patients who visited during the past three months, the proportion of patients who have any health insurance, procedures for handling foreign patients, and the disadvantages in medical care for them. RESULTS: Of the 210 respondents (183 clinics and 27 hospitals), 133 facilities (63.3%) provided medical care for foreign patients during the past three months, and 187 (89.0%) during the past year. In 102 facilities (76.7%), the number of foreign patients was fewer than 10 during the past three months. The mean number of foreign patients was 13.8 per facility (12.2 per clinic, and 23.5 per hospital). Of these foreign patients, 68.6% had any health insurance. In 172 facilities (81.9%), foreign patients were accepted in the same way as the Japanese. The main disadvantages in medical care for foreigners were difficulty in understanding because of communication problems, and default in payment of medical expenses for the foreigners with no health insurance. In 154 facilities (73.3%), no special preparation to communicate with foreign patients was provided, and few facilities could understand foreign languages except for English. In 20 facilities, fees for medical care had been left unpaid by foreign patients during the past year, and the total outstanding amount was about 23,800,000 yen. CONCLUSION: In Chiba City, many medical facilities provide medical care for foreign patients. This study suggests that support for communication with foreigners and compensation for default in medical expenses are necessary.  相似文献   
65.
The effect of nipradilol on the isoproterelol-induced depression of contractions of the soleus muscle of the anesthetized cats was studied. Isoproterenol (0.3 microg/kg) injected intravenously decreased the tension and degree of fusion of incomplete tetanic contractions of the soleus muscle of the anesthetized cats. The effect of isoproterenol was blocked by nipradilol (> or = 3 microg/kg), desnitro-nipradilol (> or = 10 microg/kg) and propranolol (> or = 10 microg/kg), but not by nitroglycerin (10-100 microg/kg). Nipradilol (30 microg/kg) and desnitronipradilol (300 microg/kg) almost completely antagonized the depressor effects of isoproterenol. These results coupled with evidence that nipradilol does not penetrate the blood-brain barrier indicate that nipradilol exerts an anti-tremor action by blocking peripheral beta2-adrenoceptors.  相似文献   
66.
To analyze the healing process after laser therapy for cervical lesions, the clinical, cytologic, histologic and colposcopic features in 109 cases were studied chronologically. The healing process of the cervical epithelium usually began from both the squamous and columnar epithelial borders, starting around the 10th day after laser therapy; the process covered the whole tissue defect with multilayered epithelium within seven weeks. Inflammatory changes also usually abated within that time. Cytomorphologically, laser therapy resulted in the occurrence of (mostly degenerated) "fiber-type" and orangeophilic cells in smears taken during the first two weeks after treatment. Tissue repair cells were seen in smears collected from the first posttherapy day through the fourth week after laser therapy. Using computer-assisted image cytometry, the reparative cells in samples taken shortly after treatment (roughly, the first to fifth days) exhibited more hyperchromatic (3-4N) nuclei than did those in later samples; however, the mean DNA content of the early reparative cells was generally concentrated around that of the 2N reference cells. These findings suggest that follow-up, including cytologic and colposcopic examination, for the early detection of residual or recurrent lesions should start in the eighth week and continue periodically for at least one year.  相似文献   
67.
A case of female alcoholic who developed liver cirrhosis with small amounts of alcohol by the common use of contraceptive agent was reported. A case was a 33-year-old female who had complained of systemic edema and jaundice. She had been drinking alcohol, while she had been taking the contraceptive agent from 20-year-old. On admission, she had a large amount of ascites with jaundice. She was diagnosed as liver cirrhosis and hepatic failure by CT scanning of abdomen and laboratory data. Her condition was temporarily improved by the abstinence and the treatment. Since she drank under hospitalization, she had to change the hospital and died after 2 months. She had been drinking for only 10 years. Her cumulative alcohol intake was also very small. She may have developed alcoholic cirrhosis with small amount of alcohol because of common use of contraceptive agent with drinking.  相似文献   
68.
Gender difference of alcohol intake and laboratory data was investigated in 165 Japanese patients with alcoholic liver cirrhosis. Mean age of first drinking and habitual drinking were higher in female. Duration of drinking was shorter in female. Although cumulative alcohol intake was larger in male, mean daily alcohol intake did not differ in both gender. Moreover, daily alcohol intake adjusted to body weight was significantly larger in female. Body mass index, serum levels of total protein, albumin and cholinesterase were significantly decreased in female. Platelet counts on admission did not differ in both gender. However, it was significantly increased in female after one month abstinence. C reactive protein, ammonia and serum levels of total bilirubin were significantly higher in female as compared to male. In conclusion, female alcoholics seems to progress to liver cirrhosis earlier because of high daily alcohol intake adjusted to body weight, poor nutritional condition and inflammation caused by endotoxin.  相似文献   
69.
BACKGROUND: Current organ shortage has led to a reconsideration of non-heart-beating cadaveric donation. METHODS: We assessed the effectivity of dual, i.e., arterial and portal-venous versus exclusive, arterial gravity perfusion for procurement of rat livers after 30 min and 60 min of cardiac arrest, analyzing the rate and homogeneity of microvascular perfusion by in situ fluorescence microscopy. RESULTS: After 30 min of cardiac arrest, a nearly 100% recovery of acinar perfusion with a sinusoidal density not significantly different from that of normal, nonischemic livers was achieved by dual gravity perfusion. Prolongation of cardiac arrest to 60 min caused an almost 50% deficit of acinar and sinusoidal perfusion (P<0.05) with a concomitant 2-3-fold increase of heterogeneity of hepatic microperfusion. Regardless of the warm ischemic time period, dually perfused livers exhibited significantly (P<0.05) higher rates of both acinar and sinusoidal perfusion with increased homogeneity of microcirculation when compared with exclusive arterial perfusion. CONCLUSION: These data underline the need and benefit of dual perfusion as well as the limitation of warm ischemic tolerance to 30 min for safe liver procurement of non-heart-beating donors.  相似文献   
70.
Liver metastasis of primary tumor is a clinically major problem. KRN7000, an alpha-galactosylceramide, significantly augments natural killer (NK) activity of spleen cells and shows strong antitumor activity in mice with lung metastasis of melanoma B16 cells. To test whether KRN7000 has an antitumor activity in mice with hepatic metastasis of tumors, we examined the effect of KRN7000 on NK activity of hepatic mononuclear cells (MNC) and the antitumor activity in mice with liver metastasis of EL-4 cells. The in vivo administration of KRN7000 significantly augmented NK activity of hepatic MNC and inhibited tumor growth of EL-4 cells in the liver more markedly than chemotherapeutic agents, leading to a relatively high rate of cured mice. In addition, it appeared that the KRN7000 treatment is effective in mice with established EL-4 tumors. Moreover, we found that KRN7000 can produce significant amounts of interleukin 2 (IL-2), IL-4, IL-12, and interferon-gamma in a dose-dependent manner. These results suggest that KRN7000 will be useful for the treatment of cancer liver metastasis.  相似文献   
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