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排序方式: 共有215条查询结果,搜索用时 15 毫秒
1.
A 55‐year‐old‐man had a laparoscopic resection of the sigmoid colon due to colon cancer with submucosal invasion. After the surgery he suffered ileus and had a laparotomy. Six months later he complained of frequent defecation. Colonoscopy confirmed a circular ulcer extending from the anal side of the anastomosis in the sigmoid colon to the mid rectum. Endoscopic ultrasound demonstrated thickening of all layers of the diseased colon and rectum. We diagnosed ischemic colitis. After intravenous drip infusion of prostaglandin, symptoms and colonic stricture gradually improved. Although abdominal angiography revealed a narrowing of the peripheral sigmoid branch of the inferior mesenteric artery, blood flow was unrestricted. Colonoscopy performed 84 days after discharge revealed an ulcer scar.  相似文献   
2.
To clarify the pathogenesis of the widely known but obscuresyndrome of sudden death with hepatic fatty metamorphosis observedin alcohol abusers, we have scrutinized both the clinical andpathological data of 11 subjects who died under such circumstancesbetween 1987 and 1993. Death followed several days of uninterrupteddrinking often with little dietary intake. The notable clinicalfeatures on arrival at the emergency room were disturbance ofconsciousness (11/11), hypotension (47/6), hypothermia (3/5),hypoglycaemia (8/11), metabolic acidosis (6/6), renal dysfunction(11/11), and hyperammonaemia (5/5). The common hepatic pathologywas the extensive appearance of numerous microvesicular fattydroplets in the hepatocytes together with varying degrees ofmacrovesicular fatty change; four subjects had an underlyingcirrhosis. Death undoubtedly results from a variety of metabolicdisturbances triggered by the combination of massive ethanolintake and starvation. The appearance of extensive microvesicularfatty change superimposed on macrovesicular fatty change wasconsidered to be an associated phenomenon  相似文献   
3.
The importance of oxygen in maintaining the functional integrity of hepatocytes has been well established in a variety of experimental models, such as in vivo , perfused liver and isolated hepatocytes. However, one of the shortcomings of these systems is their short life span. Therefore, we have examined the effects of long-term hypoxia on cellular adenine nucleotide content and cellular functions, such as albumin production, urea production and DNA synthesis, in adult rat hepatocytes in primary culture. Hepatocytes were cultured at a density of 11 × 104 and 5 × 104 cells/0.18 mL per cm2 for the study of albumin and urea production and DNA synthesis, respectively, at various oxygen tensions (20, 12, 8 and 5%) for 24 h. Cellular ATP content in cultured hepatocytes in hypoxia gradually declined, corresponding to the decrease in oxygen tension, and the cellular ATP level at 5% oxygen was approximately 20% of that at 20% oxygen. Albumin production also decreased in parallel with the decrease in cellular ATP content in cultured hepatocytes in hypoxia. However, even when cellular ATP content gradually declined corresponding with the decrease in oxygen tension in cultured hepatocytes in hypoxia, such as at 8 or 5% oxygen, urea production remained at a high level; in contrast, DNA synthesis was completely suppressed. These results suggest that the cellular ATP content decreases in cultured hepatocytes during long-term hypoxia in relation to oxygen tension and that the relationship between decreased ATP levels and liver function in cultured hepatocytes during hypoxia differs for albumin production, urea production and DNA synthesis.  相似文献   
4.
AIM: The aim of the present study was to investigate the safety and efficacy of endoscopic laser therapy for transitional cell carcinoma (TCC) of the upper urinary tract. METHODS: Tumors of the renal pelvis and ureteropelvic junction were detected by ureteroscopy. The tumors were subjected to biopsy, and after TCC was diagnosed, endoscopic laser therapy (Neodymium-YAG and Holmium-YAG) was conducted using a 6.9 Fr. flexible ureterorenoscope. RESULTS: From January 1997 to April 2002, six patients underwent ureteroscopic treatment. Tumor grade was 1 in four patients and 2 in two patients. Average tumor size was 1.45 cm. Endoscopic treatment was chosen for two patients because of the high medical risk associated with open surgery. Another patient underwent diagnostic ureteroscopy, followed immediately by endoscopic treatment. A further three patients elected to undergo ureteroscopic treatment. One patient with large (3 cm), multifocal and incompletely treated tumors died of metastatic disease 22 months after the initial operation. One patient requested nephroureterectomy one month after endoscopic treatment, and pathological examination of the resected specimen revealed no tumor. The other four patients have been followed up for a mean period of 14 months after initial treatment. Recurrence occurred in one patient, and was successfully treated by repeat endoscopic resection. None of the patients required blood transfusion or emergency open surgery. CONCLUSION: Ureteroscopic treatment of small, localized, low-grade TCC of the upper urinary tract is now a safe and feasible alternative to nephroureterectomy in selected patients.  相似文献   
5.
The vacuolating cytotoxin and urease secreted by Helicobacter pylori are thought to be virulent factors. Because vacuolation is potentiated by the presence of ammonium ion, which is produced by urease in vitro, it is of interest to examine whether cytotoxin and urease work reciprocally in the development of atrophic gastritis or duodenal ulcer. In the present study, patients (all H. pyloripositive) were divided into four groups: mild atrophic gastritis (group 1; nine patients), severe atrophic gastritis (group 2; 36 patients), duodenal ulcer with mild atrophic gastritis (group 3; 19 patients) and duodenal ulcer with severe atrophic gastritis (group 4; 12 patients). Cytotoxin production and urease activity of H. pylori isolated from these patients were analysed. Cytotoxin production was observed in four of nine (44.4%), 28 of 36 (77.8%), 11 of 19 (57.9%) and eight of 12 (66.7%) isolates from groups 1, 2, 3 and 4, respectively. Cytotoxin-producing H. pylori isolates were found significantly more in patients with severe atrophy than in patients with mild atrophy (P= 0.048). The mean of relative activity of cytotoxin in H. pylori isolate was 1. 6. ± 2. 3, 7. 9. ± 7. 4, 5. 8. ± 6. 0 and 9. 0 ± 9. 1 in groups 1, 2, 3 and 4, respectively. Helicobacter pylori isolates from severe atrophy or duodenal ulcer patients in groups 2 or 4 possessed significantly higher activity than those from non-ulcer patients in group 1 (P= 0.017 and 0.030, respectively). The mean of urease activity was 8. 6 ± 4. 6, 10. 0 ± 5. 9, 10. 0 ± 8. 5 and 11. 2 ± 7. 7 IU/mg in groups 1, 2, 3 and 4, respectively. These differences indicated no statistical significance. In each H. pylori isolate, the production of cytotoxin and urease were independent, which indicated that there was no reciprocal effect between them in vivo. Thus, cytotoxin-producing H. pylori isolates were more prevalent in patients with severe atrophic gastritis and the cytotoxin activities of H. pylori isolates from the patients with severe atrophic gastritis or duodenal ulcer were much higher than those from the patients with mild atrophic gastritis, which suggested that vacuolating cytotoxin may be a disease-inducing factor.  相似文献   
6.
The effect of cimetidine on the natural killer (NK) activityof peripheral blood lymphocytes (PBL) of 32 patients with ovariancarcinoma was studied before and after surgery or chemotherapy.There was no significant difference in the NK activity betweennormal healthy women and patients who had been disease-freefor more than a year after initial surgery, while those in patientswith a large residual tumor after surgery were profoundly suppressed.Cimetidine stimulated the NK activity in the disease-free patientsin vivo or in Vitro. In addition, cimetidine augmented the responseto phytohemagglutinin of PBL from the disease-free patients.The NK activity of PBL of patients with a large residual tumorunder chemotherapy consisting of cisplatinum, adriamycin andcyclophosphamide, "CAP," was about half of that before initiationof chemotherapy. The inhibition of the NK activity by chemotherapywas abrogated by in vitro exposure of the PBL to cimetidine.  相似文献   
7.
Questionnaires were sent to 1290 hospitals in Japan asking for data on patients with juvenile dermatomyositis (JDM) diagnosed between June 1984 and May 1994. Of the 204 patients identified by these questionnaires, 102 met the criteria for JDM. JDM is categorized into three subtypes: Banker-type JDM , Brunsting-type and fulminant-type; patients with the latter exhibit markedly elevated serum levels of creatinine phosphokinase (> 10 000 U/mL) and appear to be at risk of renal failure. Cutaneous manifestations were present in 98% of patients and preceded the appearance of other symptoms. This tendency is one of the reasons for the difficulty in some cases in diagnosing the onset of JDM. Better criteria for early treatment of JDM are needed. The results of the present study suggest that itching and calcinosis are factors that indicate a poor prognosis in patients with JDM. Muscle enzyme levels do not always reflect disease activity, suggesting that methods other than measurement of muscle enzymes, such as measurement of the levels of neoprerin and von Willebrand factor antigen, as well as magnetic resonance imaging should be used to be evaluate disease severity. Patients with Brunsting-type JDM who exhibit dysphagia and antinuclear antibody positivity and patients with Banker-type JDM should be treated aggressively. Pulse therapy should be selected as the initial therapy in patients with fulminant-type JDM.  相似文献   
8.
Famciclovir is a guanine analog antiviral drug used commonly for herpes zoster. Efficacy of famciclovir treatment has been reported to be comparable to valacyclovir treatment. Both of these medications reduce the time to complete cessation of zoster‐associated pain including post‐herpetic neuralgia, as compared to acyclovir. We conducted a multicenter, randomized, open clinical trial in order to evaluate the extent of pain relief afforded by these two antiviral drugs during the acute disease phase of herpes zoster. The study group comprised 86 immunocompetent adult patients suffering from herpes zoster, who were treated with either famciclovir or valacyclovir for 7 days. Of these, 55 patients enrolled in this study within 72 h of the onset of the rash and 31 patients after 72 h of the onset. There was a significant reduction in acute herpes zoster pain with famciclovir on day 7 and at 2–3 weeks in both of these patient groups, while with valacyclovir, there was not significant reduction in pain on day 7. Of patients aged 50 years or older, there was a significantly earlier reduction in pain with famciclovir than with valacyclovir. In addition, a significant reduction in the number of patients with pain was observed as early as days 3–4 with famciclovir treatment as compared with valacyclovir treatment. We conclude that famciclovir was superior to valacyclovir in the relief of acute pain of herpes zoster. Accordingly, famciclovir is recommended for herpes zoster patients with moderate symptoms and a visual analog scale score of under 50 mm.  相似文献   
9.
基质金属蛋白酶抑制剂KB-R7785对鼠局灶脑缺血的保护作用   总被引:8,自引:6,他引:8  
目的 研究表明,脑缺血后基质金属蛋白酶(MMPs)可以破坏血脑屏障、促进脑水肿的形成及炎性细胞的浸润、加快神经细胞的死亡,从而加重缺血性脑损害。本研究观测MMPs抑制剂、KB-R7785对缺血性脑卒中的保护作用。方法 采用线段血管内栓塞大脑中动脉(MCAO)获得小鼠脑缺血模型。观察不同时间、剂量KB-R7785对24h后脑梗塞灶体积的影响,同时应用酶谱印迹技术检测缺血后脑组织中MMPs活性。结果 酶谱印迹显示MMP-9活性在缺血后6h表达增强,24h后达峰值。MCAO前30 min单次注射KB-R7785(100mg·kg-1)可显著抑制 MMP-9的活性;单次注射或缺血后1及4.5h分次注射KB-R7785(100mg·kg-1)均可明显减小脑梗塞体积(P<0.01)。结论MMP-9可促进脑梗塞形成;MMPs抑制剂、KB-R7785具有改善缺血性脑损伤作用。  相似文献   
10.
Normal values of all IgG subclasses were determined using a sensitive ELISA in children aged from newborn to 14 years. The upper and lower limits of normal values of all IgG subclasses were obtained in all the age groups using 29 umbilical cord blood samples from full-term newborns and 308 venous blood samples from normal infants and children. The trends in the levels of IgG1, IgG2 and IgG3 with age were almost similar to previous reports. IgG4 levels decreased gradually until reaching the lowest level at 7 to 12 months and increased gradually with age, reaching a plateau at 12 to 14 years of age. Thus, the lower limit of serum IgG4 levels was determined using our method.  相似文献   
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