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961.
962.
Summary.  We have analysed the sequence variability of the banana bunchy top nanovirus (BBTV) DNA-1 sequence from 17 isolates collected throughout Vietnam, and showed that the level of DNA-1 sequence variation within Vietnam was approximately double that previously reported for Asian BBTV isolates. Furthermore, the sequences separated into two geographical subgroups that generally correlated to the northern or southern regions of Vietnam. We have also characterised an additional putative Rep-encoding component associated with some BBTV isolates from Vietnam. This component, which we have named BBTV-S3, shared 47%, 69%, 56% and 65% nucleotide sequence identity with the previously reported Rep-encoding components BBTV DNA-1, S1, S2 and Y1 respectively. Received September 14, 2001 Accepted December 20, 2001  相似文献   
963.
ObjectiveTo investigate the incidence and survival rates of primary uterine carcinosarcoma (UCS) in Korea.MethodsFrom the Korea Central Cancer Registry, we identified patients diagnosed with primary UCS between 1999 and 2018 and collected their information, including age at diagnosis, Surveillance, Epidemiology, and End Results (SEER) summary stage, and treatment. Age-standardized incidence rates (ASRs) and annual percent changes (APCs) were calculated. Baseline characteristics and overall survival (OS) were compared by study periods, ages, and stages at initial diagnosis.ResultsOverall, the incidence rate of primary UCS increased markedly during the time period: ASRs, 0.02 per 100,000 in 1999 and 0.25 per 100,000 in 2018 (APC, 13.9%; p<0.001). No difference in OS was observed between patients diagnosed in 1999–2008 and those diagnosed in 2009–2018 (5-year survival rate, 46.0% vs. 48.6%; p=0.871). Considering the mean patient age at diagnosis of UCS, we divided the study population into 2 groups. Patients aged ≥60 years had a more frequent prior radiation history, received less multi-modality treatment, and showed worse OS than those aged <60 years (5-year survival rate, 42.7% vs. 53.6%; p=0.001). In multivariate analysis, both old age at diagnosis (≥60 years) and the SEER summary stage were identified as independent poor prognostic factors for OS, whereas radiation history before the diagnosis of UCS was not.ConclusionThe incidence rate of UCS in Korea increased significantly from 1999 to 2018. Advanced stage and old age (≥60 years) at diagnosis might be poor prognostic factors for survival, but not prior radiation history.  相似文献   
964.

Background

To evaluate the changes in visual acuity, metamorphopsia, and thickness of retinal layers after epiretinal membrane (ERM) removal and to investigate factors associated with visual function.

Methods

This prospective study included 52 eyes of 52 patients who underwent surgery for idiopathic ERM. Changes in visual acuity, metamorphopsia score (M-score) using M-chart, and parafoveal thickness of each retinal layer were evaluated preoperatively and at 2-month and 6-month postoperative follow-up visits. Factors associated with visual acuity and M-score were investigated.

Results

Although continuous improvement in visual acuity and decrease in the thickness of parafoveal retinal layers following ERM removal was observed, relatively slow improvement in M-score was noted with values of 0.32?±?0.27, 0.44?±?0.46, and 0.23?±?0.23, respectively at the defined time points. A preoperative increase in the thickness of parafoveal retina was mainly caused by increased thickness of inner retinal layers. Preoperative thickness of inner nuclear layer (INL) were closely associated with preoperative, postoperative visual acuity, and preoperative M-score (p?=?0.001, 0.012, and 0.027, respectively).

Conclusions

Compared with the postoperative improvement in visual acuity, the postoperative improvement in metamorphopsia was a rather slow process. Parafoveal INL thickness was found to be a significant structural factor for visual acuity and metamorphopsia in ERM.  相似文献   
965.
An analysis of 4,514 cases of renal biopsy in Korea   总被引:7,自引:0,他引:7  
To evaluate the distribution and changing patterns of renal diseases in Korea, a total of 4,514 cases of renal biopsy collected over a 23-year period between 1973 and 1995 were reviewed. Of 4,200 cases excluding 314 unsatisfactory biopsies, adult cases comprised 59.5% and pediatric cases, 40.5%. The male to female ratio was 1.5:1 in adults and 2.2:1 in children. Glomerulonephritis (GN) comprised 80.0% of the total. The most common primary GN in adults was minimal change disease (MCD) (26.6%), followed by IgA nephropathy (IgAN) (22.1%), membranous GN (MGN) (11.8%), and membranoproliferative GN (MPGN) (5.9%). In children, the primary GN incidence rates were MCD (24.8%), IgAN (10.3%), poststreptococcal (including postinfectious) GN (PSGN) (8.6%), and focal segmental glomerulosclerosis (FSGS) (4.0%). The most common secondary GN in adults was lupus nephritis and in children Henoch-Schonlein purpura nephritis. The most common cause of nephrotic syndrome was MCD in both adults and children, followed by MGN and FSGS. The elderly, aged sixty years and older, comprised 2.7% of cases and recorded equal numbers of MCD and MGN. The proportion of the biopsies found to be seropositive for HBs antigen was 27.9%, and these showed either MGN or MPGN pattern. Repeat biopsy was performed in 168 patients, due to previous biopsy failure in 15.5%. When the primary GN cases were analyzed at 5-year intervals, the prevalence of PSGN, which was greater than 25% during the 1973-1982 period, decreased abruptly in children thereafter, whereas the prevalence of FSGS increased slowly since the 1988-1992 period in both adults and children. The decrease of PSGN and the increase of FSGS suggest a role for socioeconomic and environmental factors in Korea.  相似文献   
966.
Outcomes and costs of coronavirus disease (COVID-19) contact tracing are limited. During March–May 2020, we constructed transmission chains from 184 index cases and 1,499 contacts in Salt Lake County, Utah, USA, to assess outcomes and estimate staff time and salaries. We estimated 1,102 staff hours and $29,234 spent investigating index cases and contacts. Among contacts, 374 (25%) had COVID-19; secondary case detection rate was ≈31% among first-generation contacts, ≈16% among second- and third-generation contacts, and ≈12% among fourth-, fifth-, and sixth-generation contacts. At initial interview, 51% (187/370) of contacts were COVID-19–positive; 35% (98/277) became positive during 14-day quarantine. Median time from symptom onset to investigation was 7 days for index cases and 4 days for first-generation contacts. Contact tracing reduced the number of cases between contact generations and time between symptom onset and investigation but required substantial resources. Our findings can help jurisdictions allocate resources for contact tracing.  相似文献   
967.
PurposeErlotinib has been the only targeted agent to show significantly improved outcomes in pancreatic adenocarcinoma when combined with gemcitabine. We aimed to evaluate whether the addition of oxaliplatin to a combination gemcitabine/erlotinib treatment conferred a clinical benefit in patients with locally advanced unresectable or metastatic pancreatic cancer.Materials and MethodsChemotherapy-naïve patients with locally advanced or metastatic pancreatic cancer were randomly assigned to receive GEMOX-T [gemcitabine 1000 mg/m2 and oxaliplatin 50 mg/m2 on day 1 (D1) and D8 plus erlotinib 100 mg daily for 3 weeks] or GT (gemcitabine 1000 mg/m2 on D1 and D8 plus erlotinib 100 mg daily for 3 weeks). The primary endpoint was the overall response rate (ORR).ResultsBetween 2013 and 2016, 65 patients were assigned to a treatment group (33 in the GEMOX-T arm, 32 in the GT arm). The ORR was 18.2% [95% confidence interval (CI), 8.82–27.58] in the GEMOX-T arm and 6.2% (95% CI, 0.34–12.06) in the GT arm (p=0.051). The disease control rate was significantly superior in the GEMOX-T arm compared to the GT arm (72.7% vs. 43.8%, p=0.019). After a median follow-up of 19.7 months, the median progression-free survival (PFS) was 3.9 months for the GEMOX-T arm and 1.4 months for the GT arm (p=0.033). However, this did not translate to an improvement in overall survival. The most common grade 3 or higher hematologic adverse events were neutropenia (16.9%) and anemia (13.8%).ConclusionThe addition of oxaliplatin to a first-line gemcitabine/erlotinib regimen demonstrated higher response rates and significantly improved PFS in patients with locally advanced or metastatic pancreatic cancer.  相似文献   
968.
高效液相色谱法测定人血清中伊曲康唑浓度   总被引:1,自引:0,他引:1  
目的:本文建立了HPLC法测定血清样品中伊曲康唑的定量分析方法。方法:色谱条件:以ZORBAXTM- C18(5μm ,4-6×150mm) 为色谱柱;乙晴- 水(67-5∶32-5V/V) 为流动相,检测波长263nm ;用正庚烷:异戊醇(98-5∶1-5V/V) 作为提取液。结果:3 种浓度40、80、300ng·ml-1 回收率分别为105-05% 、100-57 % 、97-91% ( n = 6) ;日内、日间RSD 分别为3-83% 、4-05% 、3-09 % 及6-00% 、4-90 % 、4-72% ( n = 6),血清中药物的最低检测浓度为5ng·ml- 1,在5 ~600ng·ml-1 血药浓度范围内线性关系良好,r =0-9995。结论:本方法灵敏、准确、结果令人满意,适用于临床血药浓度监测  相似文献   
969.
乙型肝炎病毒基因的整合机制及对宿主的影响   总被引:1,自引:0,他引:1  
乙型肝炎病毒是导致慢性肝炎、肝纤维化、肝细胞癌的主要病因,目前认为乙型肝炎病毒基因整合在其致病机制中具有重要作用,本文试就该领域内目前研究成果做一综述.  相似文献   
970.

Background/Aims

This study investigated the antiviral effects of tenofovir disoproxil fumarate (TDF) monotherapy in nucleos(t)ide analogue (NA)-naive and NA-experienced chronic hepatitis B (CHB) patients.

Methods

CHB patients treated with TDF monotherapy (300 mg/day) for ≥12 weeks between December 2012 and July 2014 at a single center were retrospectively enrolled. Clinical, biochemical, and virological parameters were assessed every 12 weeks.

Results

In total, 136 patients (median age 49 years, 96 males, 94 HBeAg positive, and 51 with liver cirrhosis) were included. Sixty-two patients were nucleos(t)ide (NA)-naïve, and 74 patients had prior NA therapy (NA-exp group), and 31 patients in the NA-exp group had lamivudine (LAM)-resistance (LAM-R group). The baseline serum hepatitis B virus (HBV) DNA level was 4.9±2.3 log IU/mL (mean±SD), and was higher in the NA-naïve group than in the NA-exp and LAM-R groups (5.9±2.0 log IU/mL vs 3.9±2.0 log IU/mL vs 4.2±1.7 log IU/mL, P<0.01). The complete virological response (CVR) rate at week 48 in the NA-naïve group (71.4%) did not differ significantly from those in the NA-exp (71.3%) and LAM-R (66.1%) groups. In multivariate analysis, baseline serum HBV DNA was the only predictive factor for a CVR at week 48 (hazard ratio, 0.809; 95% confidence interval, 0.729-0.898), while the CVR rate did not differ with the NA experience.

Conclusions

TDF monotherapy was effective for CHB treatment irrespective of prior NA treatment or LAM resistance. Baseline serum HBV DNA was the independent predictive factor for a CVR.  相似文献   
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