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991.
目的 克隆并分析日本血吸虫 (Schistosomajaponicum ,Sj)新的抗原基因 ,为血吸虫病防治提供有效的疫苗候选分子。方法 以旋毛虫感染鼠血清为探针 ,筛选Sj成虫cDNA文库 ,对获得的阳性克隆进行PCR鉴定及测序。通过互联网对测序获得的核苷酸序列进行同源性分析 ,并预测新基因编码蛋白质的结构与功能。结果 共筛选出 9个阳性克隆 ,其插入SjcDNA片段大小在 0 .6~ 2 .1kb之间。测序分析获 5个新基因 ,其中Sj Ts1,Sj Ts3及Sj Ts5 (登录号为AY0 0 5 816 ,AF2 990 80 ,AY0 2 4 35 2 )分别编码 83,83,2 33个氨基酸组成的跨膜蛋白。Sj Ts1蛋白含 1个潜在的跨膜区 ,2个蛋白激酶C磷酸化位点、1个酪氨酸激酶磷酸化位点和 1个N 肉豆蔻酸化位点。Sj Ts3蛋白含两个跨膜区 ,1个酪蛋白激酶Ⅱ磷酸化位点。Sj Ts5蛋白为具有 5个跨膜区的跨膜蛋白 ,含 1个N 糖基化位点、2个cAMP与cGMP依赖的蛋白激酶磷酸化位点、4个蛋白激酶C磷酸化位点、1个酪蛋白激酶Ⅱ磷酸化位点和 1个N 肉豆蔻酸化位点。结论 Sj Ts1、Sj Ts3与Sj Ts5基因编码的蛋白质均为受磷酸化激活控制的跨膜蛋白 ,可能为潜在的血吸虫病疫苗候选分子 相似文献
992.
目的 研究日本血吸虫中国大陆株 2 3kDa膜蛋白 (SjC2 3)DNA疫苗诱导C5 7BL/6小鼠免疫保护作用。方法 将全长的SjC2 3基因克隆到真核表达载体pcDNA3.1,构建DNA疫苗 pcDNA3.1 SjC2 3。制备SjC2 3及IL 12的两个亚单位 p35、p4 0的DNA疫苗和对照 pcDNA3.1。 4 8只C5 7BL/6小鼠随机分为A、B、C 3组。A组小鼠肌注 10 0 μgpcDNA3.1;B组注射 10 0 μg pcDNA3.1 SjC2 3;C组肌注 pcDNA3.1 SjC2 3、pcDNA3.1 p35及pcDNA3.1 p4 0各 10 0 μg的混合物。每隔 2周各免疫 1次 ,共 3次。第 8周每鼠感染 4 5± 2条 /只尾蚴 ,4 5d后剖杀 ,计数成虫及肝内虫卵。采用免疫组化法检测SjC2 3及 p35、p4 0在小鼠局部组织内的表达 ;用脾细胞培养法检测经rSjC2 3 HD刺激后 ,攻击前、后小鼠脾细胞IL 2、IL 4、IL 10和IFN γ的水平。用Westernblotting检测血清中抗SjC2 3抗体。结果 SjC2 3以及p35、p4 0在免疫小鼠股四头肌细胞膜和细胞浆均获得表达。IL 2和IFN γ的水平攻击前、后在B组和C组均明显升高。Westernblotting检测抗SjC2 3抗体结果表明 ,免疫后两周 ,B组 8/10份血清为阳性 ,C组 9/10份血清阳性。B组和C组分别获得 2 6 .9%和 35 .4 %的减虫率 ,C组显著高于B组 (P <0 .0 5 ) ;减卵率分别为 2 2 .2 %和 2 8.4 %。结论 SjC 相似文献
993.
S ren Vraa Johnny Keller Ole Steen Nielsen Anne Grethe Jurik Olaf Myhre Jensen 《Acta orthopaedica》2001,72(1):72-77
Between 1979 and 1998, 152 patients with a soft-tissue sarcoma arising in the thigh were surgically treated in the Sarcoma Center in Aarhus, Denmark. We studied clinicopathologic factors prognostic for local recurrence and survival. 27 patients (18%) had a low-grade tumor, 26 (17%) an intermediate-grade and 99 (65%) a high-grade tumor.
27 patients (18%) were amputated and 125 (82%) had a local resection. 21 (14%) underwent a marginal resection, 82 (54%) a wide resection and 49 (32%) a compartmental resection. 32 patients were also given radiotherapy, 11 of these had a marginal resection.
The 5-year local recurrence-free rate was 91%. Multivariate analysis selected marginal resection and histological high grade as unfavorable prognostic factors for local recurrence. The 5-year survival rate was 68%. High age and histological high grade were unfavorable prognostic factors for survival in a multivariate analysis. Surgical margin influenced local recurrence, but not the overall survival. 相似文献
27 patients (18%) were amputated and 125 (82%) had a local resection. 21 (14%) underwent a marginal resection, 82 (54%) a wide resection and 49 (32%) a compartmental resection. 32 patients were also given radiotherapy, 11 of these had a marginal resection.
The 5-year local recurrence-free rate was 91%. Multivariate analysis selected marginal resection and histological high grade as unfavorable prognostic factors for local recurrence. The 5-year survival rate was 68%. High age and histological high grade were unfavorable prognostic factors for survival in a multivariate analysis. Surgical margin influenced local recurrence, but not the overall survival. 相似文献
994.
Månsson F Alves A Silva ZJ Dias F Andersson S Biberfeld G Fenyö EM Norrgren H 《Sexually transmitted infections》2007,83(6):463-467
Objectives
Sentinel surveys in Bissau, the capital of Guinea‐Bissau, have shown low prevalence of HIV‐1 but high HIV‐2 prevalence before 1998. Guinea‐Bissau experienced a civil war in 1998–1999. To examine specifically the trends of HIV prevalence from antenatal surveys in Bissau, Guinea‐Bissau in 1987–2004, and whether the civil war in 1998–1999 could have an effect on HIV prevalence levels after the conflict.Methods
Since 1987, anonymous HIV testing in delivering women has been performed at the maternity clinic, Simão Mendes National Hospital, Bissau, as part of the national sentinel surveillance programme. Consecutive sampling was performed for approximately 3 months between September and December each year. Serological analyses were performed at the National Public Health Laboratory in Guinea‐Bissau.Results
A total of 20 422 women were tested for HIV between 1987 and 2004. The total HIV‐1 prevalence increased from 0.0% in 1987 to 4.8% in 2004 and the total HIV‐2 prevalence decreased from 8.3% in 1987 to 2.5% in 2004. The HIV‐1 prevalence increased from 2.5% in 1997 to 5.2% in 1999, but stabilized in subsequent years.Conclusions
There was a significant increase in HIV‐1 prevalence in the years 1987–2004 and a significant decline in HIV‐2 prevalence over the same period. The civil war in 1998–1999 may have sparked HIV‐1 transmission, as HIV‐1 prevalence more than doubled between 1997 and 1999, but there is no evidence of a long‐term effect on the trends of HIV‐1 or HIV‐2 prevalence. 相似文献995.
We present the case of an elderly woman with a painless giant tumor of the neck. Computed tomography (CT) demonstrated a cyst-like lesion that appeared to arise from the parotid gland. The tumor was removed in toto and histopathologically diagnosed as an epithelial–myoepithelial carcinoma. Such rare carcinomas should be considered in the differential diagnosis of parotid gland malignancies. We discuss the possibilities of imaging modalities such as CT and magnetic resonance imaging (MRI) in the differentiation between benign and malignant salivary gland tumors. 相似文献
996.
Christensen S Zachariae R Jensen AB Vaeth M Møller S Ravnsbaek J von der Maase H 《Breast cancer research and treatment》2009,113(2):339-355
Background Elevated levels of depressive symptoms are generally found among cancer patients, but results from existing studies vary
considerably with respect to prevalence and proposed risk factors. Purpose To study the prevalence of depressive symptoms and major depression 3–4 months following surgery for breast cancer, and to
identify clinical risk factors while adjusting for pre-cancer sociodemographic factors, comorbidity, and psychiatric history.
Patients and methods The study cohort consists of 4917 Danish women, aged 18–70 years, receiving standardized treatment for early stage invasive
breast cancer during the 2 1/2 year study period. Of these, 3343 women (68%) participated in a questionnaire study 12–16 weeks
following surgery. Depressive symptoms (Beck’s Depression Inventory II) and health-related behaviors were assessed by questionnaire.
The Danish Breast Cancer Cooperative Group (DBCG) and the surgical departments provided disease-, treatment-, and comorbidity
data for the study cohort. Information concerning sociodemographics and psychiatric history were obtained from national longitudinal
registries. Results The results indicated an increased prevalence of depressive symptoms and major depression (13.7%) compared to population-based
samples. The pre-cancer variables: Social status, net-wealth, ethnicity, comorbidity, psychiatric history, and age were all
independent risk factors for depressive symptoms. Of the clinical variables, only nodal status carried additional prognostic
information. Physical functioning, smoking, alcohol use, and BMI were also independently associated with depressive symptoms. Conclusion Risk factors for depressive symptoms were primarily restricted to pre-cancer conditions rather than disease-specific conditions.
Special attention should be given to socio-economically deprived women with a history of somatic- and psychiatric disease
and poor health behaviors. 相似文献
997.
Background and purpose
To elaborate a method for applicator reconstruction for MRI-based brachytherapy for cervical cancer.Materials and methods
Custom-made plastic catheters with a copper sulphate solution were made for insertion in the source channels of MR-CT compatible applicators: plastic and titanium tandem ring applicators, and titanium needles. The applicators were CT and MR scanned in a phantom for accurate 3D assessment of applicator visibility and geometry. A reconstruction method was developed and evaluated in 19 patient MR examinations with ring applicator (plastic: 14, titanium: 5). MR applicator reconstruction uncertainties related to inter-observer variation were evaluated.Results
The catheters were visible in the plastic applicator on T1-weighted images in phantom and in 14/14 clinical applications. On T2-weighted images, the catheters appeared weaker but still visible in phantom and in 13/14 MR clinical applications. In the titanium applicator, the catheters could not be separated from the artifacts from the applicator itself. However, these artifacts could be used to localize both titanium ring applicator (5/5 clinical applications) and needles (6/6 clinical applications). Standard deviations of inter-observer differences were below 2 mm in all directions.Conclusion
3D applicator reconstruction based on MR imaging could be performed for plastic and titanium applicators. Plastic applicators proved well to be suited for MRI-based reconstruction. For improved practicability of titanium applicator reconstruction, development of MR applicator markers is essential. Reconstruction of titanium applicator and needles at 1.5 T MR requires geometric evaluations in phantoms before using the applicator in patients. 相似文献998.
De Ruysscher D Wanders R van Haren E Hochstenbag M Geraedts W Pitz C Simons J Boersma L Verschueren T Minken A Bentzen SM Lambin P 《International journal of radiation oncology, biology, physics》2008,71(1):132-138
PURPOSE: To determine the feasibility of high-dose continuous hyperfractionated accelerated radiotherapy in patients with inoperable non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: In a prospective, Phase I/II study, according to the risk for radiation pneumonitis, three risk groups were defined: V(20) <25%, V(20) 25-37%, and V(20) >37%. The dose was administered in three steps from 61.2 Gy/34 fractions/23 days to 64.8 Gy/36 fractions/24 days to 68.40 Gy/38 fractions/25 days (1.8 Gy b.i.d. with 8-h interval), using a three-dimensional conformal technique. Only the mediastinal lymph node areas that were positive on the pretreatment (18)F-deoxy-D-glucose positron emission tomography scan were included in the target volume. The primary endpoint was toxicity. RESULTS: A total of 48 Stage I-IIIB patients were included. In all risk groups, 68.40 Gy/38 fractions/25 days could be administered. Maximal toxicity according to the risk groups was as follows: V(20) <25% (n = 35): 1 Grade 4 (G4) lung and 1 G3 reversible esophageal toxicity; V(20) 35-37% (n = 12): 1 G5 lung and 1 G3 reversible esophageal toxicity. For the whole group, local tumor recurrence occurred in 25% (95% confidence interval 14%-40%) of the patients, with 1 of 48 (2.1%; upper one-sided 95% confidence limit 9.5%) having an isolated nodal recurrence. The median actuarial overall survival was 20 months, with a 2-year survival rate of 36%. CONCLUSIONS: High-dose continuous hyperfractionated accelerated radiotherapy up to a dose of 68.40 Gy/38 fractions/25 days (a biologic equivalent of approximately 80 Gy when delivered in conventional fractionation) in patients with inoperable NSCLC and a V(20) up to 37% is feasible. 相似文献
999.
MRI-guided 3D optimization significantly improves DVH parameters of pulsed-dose-rate brachytherapy in locally advanced cervical cancer 总被引:1,自引:0,他引:1
Lindegaard JC Tanderup K Nielsen SK Haack S Gelineck J 《International journal of radiation oncology, biology, physics》2008,71(3):756-764
PURPOSE: To compare dose-volume histogram parameters of standard Point A and magnetic resonance imaging-based three-dimensional optimized dose plans in 21 consecutive patients who underwent pulsed-dose-rate brachytherapy (PDR-BT) for locally advanced cervical cancer. METHODS AND MATERIALS: All patients received external beam radiotherapy (elective target dose, 45 Gy in 25-30 fractions; tumor target dose, 50-60 Gy in 25-30 fractions). PDR-BT was applied with a tandem-ring applicator. Additional ring-guided titanium needles were used in 4 patients and a multichannel vaginal cylinder in 2 patients. Dose planning was done using 1.5 Tesla T(1)-weighted and T(2)-weighted paratransversal magnetic resonance imaging scans. T(1)-weighted visible oil-containing tubes were used for applicator reconstruction. The prescribed standard dose for PDR-BT was 10 Gy (1 Gy/pulse, 1 pulse/h) for two to three fractions to reach a physical dose of 80 Gy to Point A. The total dose (external beam radiotherapy plus brachytherapy) was normalized to an equivalent dose in 2-Gy fractions using alpha/beta = 10 Gy for tumor, alpha/beta = 3 Gy for normal tissue, and a repair half-time of 1.5 h. The goal of optimization was dose received by 90% of the target volume (D(90)) of > or =85 Gy(alpha/beta10) in the high-risk clinical target volume (cervix and remaining tumor at brachytherapy), but keeping the minimal dose to 2 cm(3) of the bladder and rectum/sigmoid at <90 and <75 Gy(alpha/beta3), respectively. RESULTS: Using three-dimensional optimization, all dose-volume histogram constraints were met in 16 of 21 patients compared with 3 of 21 patients with two-dimensional library plans (p < 0.001). Optimization increased the minimal target dose (D(100)) of the high-risk clinical target volume (p < 0.007) and decreased the minimal dose to 2 cm(3) for the sigmoid significantly (p = 0.03). For the high-risk clinical target volume, D(90) was 91 +/- 8 Gy(alpha/beta10) and D(100) was 76 +/- 5 Gy(alpha/beta10). The minimal dose to 2 cm(3) for the bladder, rectum, and sigmoid was 73 +/- 6, 67 +/- 6, and 69 +/- 6 Gy(alpha/beta3), respectively. CONCLUSION: The results of our study have shown that magnetic resonance imaging-guided optimization of PDR-BT for locally advanced cervical cancer significantly improved the dose-volume histogram parameters. 相似文献