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71.
The effect of cigarette smoke gas phase on the survival time of Paramecium aurelia was studied with an intermittent method of exposure. This method simulated human smoking and revealed the ability of activated charcoal to reduce the toxic effect of gas phase.  相似文献   
72.
We investigated whether correlations between mRNA levels of cytokines versus other proteins from patchy lesion could estimate cytokine paracrine signaling in vivo. Experiments with rat experimental autoimmune myocarditis (EAM), a patchy myocarditis model, indicated IL-1 and other protein levels were correlated, indicating paracrine signaling pathways in vivo.  相似文献   
73.
OBJECTIVE: To investigate whether preoperative corticosteroid administration plays a role in attenuating postoperative morbidity. SUMMARY BACKGROUND DATA: There is as yet no consensus on the beneficial effects of steroids in alleviating surgical stress. METHODS: A total of 66 patients undergoing surgery for thoracic esophageal cancer were randomly categorized preoperatively into two groups of 33 patients each. One group was administered an intravenous infusion of methylprednisolone (10 mg/kg body weight) 30 minutes before the surgery (MP group), while the other group received a placebo infusion (control group). The primary endpoint was organ system failure during the first 7 days after surgery. Comparisons of surgery-related complications, cytokine responses, and blood counts were also made between the two groups. RESULTS: The percentage of patients in the MP group who had one or more organ system failures was 33%, significantly lower than the corresponding percentage of 61% in the control group. The surgery-related complication rate and long-term survival rate were similar in the two groups. The peak plasma levels of interleukin (IL)-1 receptor antagonist, IL-6, and IL-8 were significantly lower in the MP group than in the control group. Changes in the plasma levels of IL-10 were significantly larger in the MP group. No significant differences in the circulating lymphocyte and neutrophil counts were observed between the groups. CONCLUSIONS: The results suggest that prophylactic administration of corticosteroids is associated with a decrease in postoperative morbidity in patients undergoing invasive surgery. The laboratory data suggest that corticosteroids may attenuate surgical stress-induced inflammatory responses both directly by suppressing the release of proinflammatory cytokines and via inducing IL-10 synthesis.  相似文献   
74.
A 59-year-old man with a long history of hypertension and diabetes was admitted to our hospital with acute type B aortic dissection 14 days after the sudden onset of back pain. The dissecting descending thoracic aorta was enlarged to 5.2 cm in diameter, and laboratory tests showed an elevated white blood cell count (15 530/mm3) and an increased C-reactive protein level (19.2 mg/dl). Computed tomography performed 2 days after admission revealed rapid growth of the aortic dissection. Blood cultures obtained upon admission were positive for Salmonella. Impending rupture of the aortic dissection complicated by Salmonella infection was strongly suspected, and the patient underwent emergency surgery consisting of debridement and prosthetic graft placement covered by an omental flap. In this case, it is believed that insidious Salmonella aortitis caused acute type B aortic dissection.  相似文献   
75.
Background Preoperative biliary drainage (PBD) is associated with bacterial contamination of bile, but the effects of PBD on morbidity after pancreatoduodenectomy remain controversial. The aim of this study was to characterize bile contamination to develop successful specific antibiotic prophylactic strategies for pancreatoduodenectomy. Methods Ninety-one consecutive patients who underwent pancreatoduodenectomy for periampullary tumor were prospectively evaluated. Prophylactic antibiotics were selected based on preoperative bile cultures. Bile cultures and postoperative complications were compared in 46 patients who underwent PBD (drainage group) versus 45 patients who did not (nondrainage group). Results The incidence of positive bile cultures was higher in the drainage group (78%) than in the nondrainage group (36%) (P < 0.001). In the drainage group, positive bile cultures were frequently polymicrobial (61%) and demonstrated resistance to several antibiotics, including cefazolin (83%), cefmetazole (72%), and cefpirome (64%). Overall morbidity (30% and 22%) and infectious morbidity (13% and 11%) did not differ significantly between the drainage and nondrainage groups, respectively. Conclusions PBD had a notable influence on bile microbial contamination, including a higher rate of antibiotic resistance. Therefore, specific antibiotic prophylaxis based on bile culture is required for preventing infectious complications in pancreatoduodenectomy patients who undergo PBD.  相似文献   
76.
Sepsis causes impairment of diaphragmatic contractility and endurance capacity. Nitric oxide (NO) produced via inducible NO synthase (iNOS) has been implicated in the pathogenesis. Peroxynitrite, a NO-derived powerful oxidant, may be responsible for infection-induced diaphragmatic muscle failure. Therefore, we examined whether ONO1714, a new selective iNOS inhibitor, prevents sepsis-induced diaphragmatic dysfunction. Fifty male Golden-Syrian hamsters were randomly divided into five groups: hamsters that underwent sham laparotomy alone and received saline injection (Group Sham), those that underwent cecal ligation with puncture (CLP) and received saline injection (Group Sepsis), those that underwent sham laparotomy and received injection of ONO1714 0.3 mg/kg (Group Sham-ONO1714high), those that underwent CLP and received ONO1714 0.1 mg/kg (Group Sepsis-ONO1714low), and those that underwent CLP and received ONO1714 0.3 mg/kg (Group Sepsis-ONO1714high). ONO1714 or saline was intraperitoneally injected 10 min before surgery. Diaphragmatic contractility was assessed in vitro using diaphragm muscle strips excised 24 h after operation. Diaphragm fatigability was assessed by time until tension decreased to 50% of the initial value (T50%) during fatigue trials. Twitch, tetanic tensions, and T50% during fatigue trials were reduced in Group Sepsis. Pretreatment with ONO1714 dose-dependently attenuated sepsis-induced diaphragmatic contractile profiles and endurance capacity. CLP increased plasma nitrite/nitrate (NOx; stable NO metabolites), and diaphragm malondialdehyde (MDA; a product of lipid peroxidation), positive immunostaining for nitrotyrosine (peroxynitrite footprint), and iNOS activity. ONO1714 attenuated the increase. This beneficial effect of ONO1714 may be attributable, in part, to inhibition of peroxynitrite-induced lipid peroxidation in the diaphragm. IMPLICATIONS: Sepsis impairs diaphragmatic contractility and endurance capacity, which may be involved in acute respiratory failure. Pretreatment with ONO1714, a new selective inducible nitric oxide synthase inhibitor, attenuated sepsis-induced diaphragmatic dysfunction in hamsters.  相似文献   
77.
This study was conducted to elucidate the real benefit of postoperative long-term surveillance for 10 years in patients who underwent curative resection for pathological stage I lung cancer. In 1995 and 1996, 100 patients with p-stage I lung cancer underwent curative resection. Of those, 20 patients were excluded because they did not comply with the follow-up regimen. Our follow-up regimen comprised a physical examination including a posterolateral chest radiograph and blood laboratory test every 6 months for up to 2 years, followed by once a year up to 10 years after resection. In addition, CT generally encompassed the lung apices to the lowest edge of the liver and was performed with intravenous contrast once every two years. As a result, among 80 patients, nine recurrences (11%) and seven metachronous second primary lung cancers (9%) were detected. Of 16 malignancies detected, six underwent curative reoperation The 5-year survival rates after the discovery of recurrence and of second primary lung cancer were 22% and 72%, respectively. The average survival of the six reoperated patients was 226 days longer than that of the remaining patients. For the calculation of the costs per life-year gained (LYG) of our follow-up program, an estimated survival benefit of 226 days was used. Consequently, the costs per LYG were calculated at almost 4,500,000 yen. In conclusion, the costs per LYG seem to be acceptable in the light of Japanese average annual earnings. In addition, this follow-up regimen seemed to show a clear survival benefit for patients with metachronous second primary lung cancer. However, for patients with lung cancer recurrence, the perceived benefit was nominal.  相似文献   
78.
79.
This report presents the case of a common hepatic artery (CHA) pseudoaneurysm secondary to postoperative pancreatic fistula (POPF) after pancreatoduodenectomy (PD), which was successfully treated using a coronary covered stent. A 70-year-old female underwent subtotal stomach-preserving PD for middle cholangiocarcinoma. POPF was identified on postoperative day (POD) 7, and the patient suddenly lost 500 ml of blood via the abdominal drain on POD 19. Urgent celiac arteriography revealed a CHA pseudoaneurysm. A coronary covered stent was placed to prevent rupture of the pseudoaneurysm and to maintain hepatic arterial flow, instead of performing transarterial embolization. No vascular adverse events were encountered during or after the procedure. Computed tomography and angiography showed a patent stent graft and good hepatic arterial flow 9 months after placement of the stent. Endovascular stent-graft placement not only treated the pseudoaneurysm, but also preserved the arterial blood flow. This report describes the placement of a covered stent graft for delayed hemorrhage after PD.  相似文献   
80.
For vascular occlusive disease, an autologous vein graft is the most suitable conduit for arterial reconstruction. Intimal hyperplasia, resulting from the migration and proliferation of vascular smooth muscle cells, is a major obstacle to patency after vein grafting. The degree to which the function of nitric oxide (NO) in the vein graft is preserved has been reported to be associated with the magnitude of intimal hyperplasia. Serotonin (5-HT) is released from platelets in the vascular system and plays physiological roles in controlling the vascular tone. The subtype receptors contributing to the 5-HT-induced mechanical responses vary by vessel type (artery and vein) and among species (dogs, rabbits, rats, and so on). Recent studies have demonstrated that 5-HT induces vasoconstriction through the activation of 5-HT2A receptors in smooth muscle cells or vasodilatation through the activation of endothelial 5-HT1B receptors in arteries from various animals. However, the effects of 5-HT have not been clarified in grafted veins. We herein demonstrate the responses to 5-HT in un-operated veins and then autogenous vein grafts. Next, we describe the effects of chronic in vivo administration of Rho-kinase inhibitors and 5-HT2A receptor antagonists, both of which reduce the 5-HT-induced contraction and intimal hyperplasia in vein grafts. Further studies targeting 5-HT are required to evaluate its possible benefits for autologous vein grafts with respect to vasospasm, function, and patency.  相似文献   
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