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41.
To investigate the prevalence of spotted fever group rickettsioses in Korea, a serosurvey of Japanese spotted fever rickettsiosis in patients with acute febrile illness was conducted with an indirect immunofluorescence assay. Overall, 19.88% of the patients were found to have polyvalent antibody against Rickettsia japonica. This study is the first documentation of spotted fever group rickettsiosis in Korea.  相似文献   
42.
The modifying potential of capsaicin (CAP) on lesion development was examined in a rat multiorgan carcinogenesis model. Groups 1 and 2 were treated sequentially with diethylnitrosamine (DEN) (100 mg/kg, ip, single dose at commencement), N-methylnitrosourea (MNU) (20 mg/kg, ip, 4 doses at days 2, 5, 8, and 11), and N,N-dibutylnitrosamine (DBN) (0.05% in drinking water during weeks 3 and 4). Group 3 received vehicles without carcinogens during the initiation period. Group 4 served as the untreated control. After this initiating procedure, Groups 2 and 3 were administered a diet containing 0.01% CAP. All surviving animals were killed 20 weeks after the beginning of the experiment and the target organs examined histopathologically. The induction of GST-P+ hepatic foci in rats treated with carcinogens was significantly inhibited by treatment with CAP. CAP treatment significantly decreased the incidence of adenoma of the lung but increased the incidence of papillary or nodular (PN) hyperplasia of the urinary bladder. The tumor incidence of other organs, such as the kidney and thyroid, was not significantly different from the corresponding controls. These results demonstrated that concurrent treatment with CAP not only can inhibit carcinogenesis but can also enhance it depending on the organ. Thus, this wide-spectrum initiation model could be used to confirm organ-specific modification potential and, in addition, demonstrate different modifying effects of CAP on liver, lung, and bladder carcinogenesis.  相似文献   
43.
The spleen may be preserved during distal pancreatectomy (DP) for benign disease. The aim of this study was to compare the perioperative and postoperative courses of patients with conventional DP and spleen-preserving distal pancreatectomy (SPDP) for benign lesions or tumors with low-grade malignant potential occurred at the body or tail of the pancreas. A retrospective analysis was performed for the hospital records of all the patients undergoing DP and SPDP between January 1995 and April 2006. One-hundred forty-three patients underwent DP and 37 patients underwent SPDP. There were no significant differences in age, sex, indications of operation, estimated blood loss, operative time, and postoperative hospital stay between the two groups. Pancreatic fistula occurred in 21 (13.3%) patients following DP and in 3 (8.1%) following SPDP without a significant difference (p=0.081). Portal vein thrombosis occurred in 4 patients after DP. Splenic infarction occurred in one patient after SPDP. Overwhelming postosplenectomy infection was observed in one patient after DP. SPDP can be achieved with no increase in complication rate, operative time, or length of postoperative hospitalization as compared to conventional DP. Additionally, it has the advantage of reducing the risk of overwhelming postsplenectomy infection and postoperative venous thrombosis.  相似文献   
44.
Vascular endothelial growth factor (VEGF) is known to play a key role in tumor angiogenesis. The tumor-suppressor gene p53 has been thought to regulate VEGF. We investigated the effect of VEGF on esophageal carcinoma and the correlation between VEGF and p53. Tissue samples were taken from 81 patients with esophageal carcinoma after surgery. VEGF and p53 expressions were examined by immunohistochemical staining. Microvessels in the tumor stained for CD34 antigen were also counted. VEGF and p53 expressions were observed in 51.3% (41/80) and 51.9% (41/79), respectively. The microvessel density was 70.9+/-6.7 (mean+/-SE) in VEGF-positive group and 68.7+/-5.1 in VEGF-negative group. However, no correlation was noted between VEGF and p53 expression. Whereas the tumor size, nodal status, depth of invasions, and tumor stage were associated with poor overall survival, VEGF expression or p53 expression was not. These results indicate that VEGF and p53 are highly expressed in esophageal carcinomas. Since the VEGF expression is not correlated with the p53 expression, microvessel density or clinicopathological findings, further studies with other angiogenic molecules are needed to determine the role in esophageal carcinomas.  相似文献   
45.
The present paper examined whether people employ different support-gaining strategies toward various sources of support. In Study 1, 231 Taiwanese undergraduates were asked the frequency of each strategy they used for three support types: tangible, psychological, and informational, from four support sources: parents, professors, same-sex close friends, and same-sex acquaintances. In Study 2, 363 undergraduates were asked to think of an opposite-sex friend: an acquaintance, a close friend, or romantic partner, and write the frequency of each strategy they used. Results of ANOVA indicated that main effects of source and strategy and a three-way interaction of source by strategy by gender were significant. In Study 1, the students used various strategies most frequently toward parents and same-sex close friends, and least frequently to professors, and in Study 2, more frequently to close friends and romantic partners than to acquaintances. The strategy most often used was reasoning, followed by entreaty, roundabout request, exploitation, promise of reward, exhortation, and threat, in the descending order. No effect was found for the support type factor.  相似文献   
46.
Currently, Korea is a low endemicity country for HAV, especially in children. However, recent reports of hepatitis A outbreaks show that there has been a shift of disease incidence to adolescents and young adults, with 2 cases of acute liver failure in one reported outbreak. We need to study the immune status for HAV in order to provide information for the establishment of preventive measures and possible consequences of HAV in Korea. A total of 334 infants, children and adolescents less than 20 years of age living in rural areas of Kyonggi Province, Korea were evaluated for anti-HAV immune status in 1996. Five hundred and eighty-four primary school children living in the same area were separately evaluated for the natural seroconversion rate between 1993 and follow-up samples taken in 1996. Anti-HAV IgG antibody was measured by enzyme immunoassay (HAVAB EIA kit, Abbott Laboratories, Chicago, Illinois, USA). In comparison with previous reports of seroprevalence rates, our data confirmed a dramatic drop in seroprevalence rates among children and adolescents under 20 years of age living in rural areas, from over 63.8% two decades ago to 4.6% in 1996. Natural acquisition of HAV antibody in primary school children rarely occurs, registering only 0.5% during three years. Several outbreaks in young adults during 1996-1998 suggested that immunity against HAV in this population is so low that massive outbreaks are unavoidable. Teenagers and young adults, especially soldiers, who are likely to be exposed to contaminated food or water, would also have a greater risk of hepatitis A. Immunizing children with HAV vaccine as a routine schedule should also be considered in Korea in the future, particularly if the disease burden could be estimated and the cost-effectiveness of the vaccine could be proved.  相似文献   
47.
In order to test the hypothesis that specimens blocking with a neutralizing reagent below the cutoff of the Chlamydiazyme enzyme immunoassay represent infected patients, we used direct fluorescent-antibody staining for elementary bodies (EBs) and PCR to confirm results for cervical swabs collected from 55,963 women and urethral swabs or first-void urine (FVU) samples collected from 5,781 men attending physicians' offices in the Toronto, Canada, area. Within a grey zone arbitrarily selected to represent values up to 40% below the positive threshold of the test run, 134 cervical swabs, 44 urethral swabs, and 39 FVU specimens exhibited a blocking response ( > 50% reduction in signal). Three or more EBs were observed in each of 98 cervical swabs (73.1%), 38 urethral swabs (86.4%), and 21 FVU specimens (53.8%). Of the 36 cervical swabs with fewer than three EBs, 33 were PCR positive; the positive PCR results for male specimens were 6 of 6 urethral swabs and 17 of 18 FVU samples. Application of the blocking test to specimens negative in the Chlamydiazyme enzyme immunoassay but having optical densities within 40% of the cutoff added 14.2% (217 of 1,531 specimens) more positive results to the survey. A total of 213 of 217 samples (98.2%) were reconfirmed as having EBs or DNA.  相似文献   
48.
Two endocervical swabs from each of 1,123 women were collected into manufacturer-supplied transport tubes and tested for Chlamydia trachomatis by a polymer conjugate-enhanced (PCE) enzyme immunoassay (EIA) (IDEIA PCE Chlamydia; DAKO) and a ligase chain reaction assay (LCx Chlamydia; Abbott). After confirmation by the EIA blocking test, the sensitivity of the IDEIA PCE remained at 91.8% and the specificity increased from 98.2 to 99.8% compared to LCx.  相似文献   
49.
First-void urine specimens from 683 men (592 without symptoms) were tested for Chlamydia trachomatis by a polymerase chain reaction (PCR) with KL1 and KL2 plasmid primers and by a Chlamydiazyme enzyme immunoassay (EIA). Thirty-seven specimens were confirmed to be positive by using the EIA blocking reagent and a second set of plasmid primers (T1 and T2). By comparing unconfirmed PCR results (KL1 and KL2 primers only) with the blocked Chlamydiazyme EIA results, the sensitivity and specificity of PCR were 100% (37 of 37 specimens) and 99.5% (643 of 646 specimens), respectively. Three additional specimens were negative by EIA but positive by PCR and were confirmed to be positive with primers T1 and T2. Two of the three specimens were from men with symptoms. The confirmatory PCR assay performed equally well in detecting positive specimens from symptomatic (31 of 31) and asymptomatic (9 of 9) men. Comparison of confirmatory testing of first-void urine specimens by PCR and EIA showed that PCR was 100% sensitive (40 of 40 specimens) and that the EIA was 92.5% sensitive (37 of 40 specimens) but that the assays were equally specific (100%).  相似文献   
50.
Focal glomerulonephritis was induced in rats, by a single intravenous injection of anti-Thy-1.1 antibody (ATS). One hour after the administration, the glomeruli of affected rats developed necrotic changes of the mesangial cells while after two hours, mesangiolytic changes appeared. From six days onwards, focal segmental mesangial proliferation which persisted until 30 days, occurred. This is thought to be the first report of experimental nephritis induced by pure anti-mesangial antibody.  相似文献   
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