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991.
Abstract:  Surgical as well as conservative treatment has been described for fibroadenomas. Both have disadvantages. A minimally invasive treatment, ultrasound-guided, vacuum-assisted percutaneous excision has been shown to facilitate the removal of all imaged evidence of benign breast lesions, including fibroadenomas up to 3 cm in diameter. This study is performed to assess the long-term outcome of ultrasound-guided percutaneous excision as a minimally invasive treatment for fibroadenomas. A retrospective review of 69 consecutive fibroadenomas treated with ultrasound-guided percutaneous excision between May, 2001 and December, 2005 was carried out. All these lesions underwent percutaneous excision of all imaged lesion evidence. Clinical and sonographic follow-up was recommended for all patients every 6 months. Initial size, location, and patient age were recorded for each treated lesion. Of 69 lesions treated, 52 were available for follow-up. The median follow-up period was 22 months, with a range of 7 to 59 months. At 6 months, there were no fibroadenoma recurrences. Follow-up sonography demonstrated recurrences in 13 lesions distributed across eight patients. The overall recurrence rate was 15% (8/52) with an actuarial recurrence rate of 33% at 59 months. All of the recurrences were in lesions which were larger than 2 cm in size at initial presentation. Our data suggest that the mechanism of recurrence is the regrowth of retained lesion fragments too small to be detected by ultrasound—not the incomplete excision of all imaged lesion evidence. Despite successful percutaneous excision, fibroadenomas do recur. Lesions smaller than 2 cm in size, so treated, do not need additional therapy or surveillance. Fibroadenomas larger than 2 cm are prone to recurrence and require additional treatment.  相似文献   
992.
目的探讨永磁型低场强开放式磁共振膝关节运动成像T2*WI与T1WI两种图像显示膝关节交叉韧带的特点及膝关节运动成像的检查方法。方法采用日立AIRIS-Ⅱ0.3T永磁型磁共振(magneticresonance,MR),对40例正常膝关节行斜矢状面T2*WI和T1WI运动成像扫描,对图像所显示膝关节交叉韧带的情况进行分析,同时对图像进行电影放映,显示膝关节交叉韧带在不同屈曲度时的情况。结果40例膝关节受检者中,斜矢状面T2*WI和T1WI对膝关节前、后交叉韧带的显示均较好,但吖聊更优于T1WI。结论磁共振具有多层面多方位成像的功能和良好的软组织对比,能清晰显示膝关节各解剖结构,尤其是斜矢状面T2*WI对交叉韧带的显示。采用低场磁共振膝关节作运动成像时不但交叉韧带显示良好,而且运动成像时随膝关节屈曲程度的不同,交叉韧带的变化情况也得以清晰显示。  相似文献   
993.
HIV-1 specific HLA-B-restricted CD8+ T cell responses differ from HLA-C-restricted responses in antiviral effectiveness. To investigate possible reasons for these differences, we characterized the frequency and polyfunctionality of immmunodominant HLA-B*57/B5801- and HLA-Cw*07-restricted CD8+ T cells occurring concurrently in nine study subjects assessing IFN-γ, TNF-α, IL-2, MIP-1β, and CD107a by flow cytometry and analyzed sequence variation in targeted epitopes. HLA-B*57/5801 and HLA-Cw*07 restricted CD8+ T cells did not differ significantly in polyfunctionality (p = 0.84). Possession of three or more functions correlated positively with CD4+ T cell counts (r = 0.85; p = 0.006) and monofunctional CD8+ T cells inversely correlated with CD4 cell counts (r = −0.79; p = 0.05). There were no differences in polyfunctionality of CD8+ T cells specific to wildtype versus mutated epitopes. These results suggest that loss of polyfunctionality and increase in monofunctional HIV-1-specific CD8+ T cells are associated with disease progression independent of restricting HLA allele. Furthermore, sequence variation does not appear to significantly impact CD8+ T cell polyfunctionality in chronic HIV-1 infection.  相似文献   
994.
A novel HLA-C allele, Cw*0824, which was identified from an individual of the Han Chinese, differs from Cw*080101 at codon 222 (GAG > AAG ) in exon 4, which results in an amino acid change Glu222Lys.
In recent years, many human leukocyte antigen (HLA)-C alleles have been identified. Up to date, 23 different Cw*08 alleles have been identified according to the IMGT/HLA Database release 2.25.2 May 2009 (1) . Here, we describe the identification of the novel allele HLA-Cw*0824 that was found during routine high resolution sequence-based typing (SBT) of a Chinese stem cell voluntary donor. The HLA alleles of the donor were typed as A*11, 24; B*15, 46; and DRB1*09, 12.  相似文献   
995.
Detection of CD4+ T cells specific for tumor‐associated antigens is critical to investigate the spontaneous tumor immunosurveillance and to monitor immunotherapy protocols in patients. We investigated the ability of HLA‐DR*1101 multimers to detect CD4+ T cells specific for three highly promiscuous MAGE‐A3 derived peptides: MAGE‐A3191–205 (p39), MAGE‐A3281–295 (p57) and MAGE‐A3286–300 (p58). Tetramers stained specific CD4+ T cells only when loaded with p39, although all peptides activated the specific T cells when presented by plastic‐bound HLA‐DR*1101 monomers. This suggested that tetramer staining ability was determined by the mode rather than the affinity of peptide binding to HLA‐DR*1101. We hypothesized that peptides should bear a single P1 anchor residue to bind all arms of the multimer in a homogeneous register to generate peptide‐HLA‐DR conformers with maximal avidity. Bioinformatics analysis indicated that p39 contained one putative P1 anchor residue, whereas the other two peptides contained multiple ones. Designing p57 and p58 analogues containing a single anchor residue generated HLA‐DR*1101 tetramers that stained specific CD4+ T cells. Producing HLA‐DR*1101 monomers linked with the optimized MAGE‐A3 analogues, but not with the original epitopes, further improved tetramer efficiency. Optimization of CD4+ T‐cell epitope‐binding registers is thus critical to generate functional HLA‐DR tetramers.  相似文献   
996.
HLA-A2 is the most frequent HLA-A allele in all ethnic populations, and an important restriction element for peptide presentation to T cells in infectious disease and cancer. However, the HLA-A2 supertype consisting of up to 75 subtypes, mutation studies and analyses using cytotoxic T lymphocytes suggest the functional relevance of subtype-specific differences in HLA-A2 molecules for peptide binding and T-cell recognition. Therefore, it is necessary for T-cell response study to discriminate the HLA-A2 subtypes and to understand the profile of HLA-A2 allellc distribution in a given population. In this study, we developed a simple, robust approach based on the nested polymerase chain reaction using sequence-specific primers (PCR-SSP) to discriminate 17 HLA-A2 subtypes which cover the most HLA-A2 alleles (〉 99% allele frequency) reported in Chinese, using 15 combinations of 19 allelic specific primers. In the first round of PCR, 3 combinations of 5 primers were used to determine whether the tested sample was HLA-A2 positive, meanwhile the subtypes of HLA-A*0209 and HLA-A*0215N were determined for the variant position of these two subtypes is in exon 4 instead of exon 2, 3. Samples of HLA-A2 positive were subtyped in the second round of PCR, using PCR products of the first round as templates. This strategy was applied to test the samples of 78 random HLA-A2 positive individuals for their HLA-A2 subtypes. Those samples were screened for HLA-A2 positive by the first round PCR-SSP from 154 healthy blood donors in Wuhan, China. The subtyping results were verified by using flow cytometric analysis (FCM) with HLA-A2 specific monoclonal antibody BB7.2 and DNA sequencing. The typing results of the samples show 50.7% random individuals in the population carry HLA-A2, HLA-A*0201 ranks the first (allele frequency = 15.5%), followed by A*0207 (5.8%), A*0206 (4.7%), A*0203 (2.6%), A*0210 (0.7%), and these 5 alleles account for 99.0% HLA-A2 subtypes of allele frequency. Our study indicates that the developed typing method is simple and reliable for HLA-A2 subtyping in Chinese, and the profile of allelic distribution of HLA-A2 subtypes is revealed in the population of Wuhan, China.  相似文献   
997.

Background

Although aneurysm formation accompanying parenchymal hemorrhage is one of devastating complications in the central nerves system (CNS), imaging studies of the brain are not routinely warranted in patients with infective endocarditis (IE). To assess the clinical importance for detecting silent lesions in the central nervous system, we investigated hypointense signal spots detected on the brain T2*-weighted MR imaging in patients with IE.

Methods and results

Eleven patients with IE were retrospectively reviewed. Seven patients (63.6%) showed hypointense signal spots on T2*-weighted MR images. The number of hypointense signal spots increased within only a few weeks in five patients.

Conclusion

The brain T2*-weighted MR imaging in patients with IE may have a potential role to detect CNS lesions with clinical significance of potentially high risk of intracranial hemorrhage. T2*-weighted hypointense signal spots may be specific to brain involvement, and be quite useful in monitoring CNS lesions associated with IE, even if they are asymptomatic.  相似文献   
998.
Carbamazepine (CBZ) is frequently used for treating epilepsy, but this drug causes cutaneous adverse drug reactions (cADRs) that may range from mild to severe. It is reported recently that the human leukocyte antigen HLA‐B*1502 is associated with Stevens‐Johnson syndrome (SJS) induced by CBZ in Han Chinese. We examined HLA class I in 15 Japanese patients who fulfilled the diagnostic criteria for CBZ‐induced cADRs (mild in 10 and severe = SJS in 5). HLA‐B*1518, HLA‐B*5901 and HLA‐C*0704 alleles showed higher relative risks (above 10.0) for severe cADRs. The haplotype (HLA‐A*2402‐B*5901‐C*0102) had high relative risk (16.09) for severe cADRs. In patients with severe cADRs, frequencies of HLA‐A*1101, HLA‐A*3303, HLA‐B*1501, HLA‐B*4403, HLA‐B*5101, HLA‐B*5201, HLA‐C*0702, and HLA‐C*1202 alleles are relatively lower than in the Japanese population. These data may suggest that HLA‐B*5901 is one of the candidate markers for CBZ‐induced SJS in Japanese.  相似文献   
999.
目的采用USC*PACK软件建立中国癫癎儿童拉莫三嗪的群体药代动力学(PPK)模型,促进个体化用药。方法回顾性收集60例癫癎患儿应用拉莫三嗪(LTG)的临床数据,并根据联合用药情况,将114个血药浓度点分成LTG+丙戊酸(VPA)组(n=56)、LTG+肝药酶诱导剂(EI)组(n=26)、LTG+EI+VPA组(n=16)及单用LTG组(n=16)。血药浓度均为临床常规监测的稳态浓度。应用USC*PACK软件中的非参数最大期望程序(NPEM Program),推算最优的PPK参数值,并建立模型。应用此模型和USC*PACK软件中的贝叶斯拟合程序(Bayesian fitting program),对患儿的血药浓度进行预测;求算平均预测误差(MPE),预测误差均方(MSPE)判断预测的准确度和精密度,验证PPK模型。结果最大似然值为-192.87,LTG的最佳PPK参数值为:Ka=(1.97±1.66)h^-1;Vs=(1.07±0.89)L/kg;Kel=(0.05±0.05)h^-1。血药浓度拟合值与观测值的相关系数r=0.99,回归方程为YOBS=,=-0.09+1.05×YPRED(R^2=0.98,P〈0.001)。MPE为-0.16μg/mL,MSPE为0.28(μg/mL)^2。结论在USC*PACK软件中,应用自行建立的PPK模型和Bayes法,估算个体PK参数,再进一步算出半衰期、峰谷浓度以及调药后的峰谷浓度,甚至可以模拟出调药前后的药时曲线,满足临床上的多种需求,使得临床用药从传统的经验用药模式提高到科学的个体化用药模式。  相似文献   
1000.
Dysregulation of the immune response has been proposed as a precipitating factor of schizophrenia, and human leukocyte antigens (HLA) play a critical role in regulating the cascade of immunological reaction. Hence, many studies have investigated the relationship between the HLA system and schizophrenia. HLA is a complex gene family that contains several highly polymorphic genes, while the HLA-A gene is the most often studied gene to be associated with schizophrenia in the literature. A recent study reported that the interaction of the HLA-A10 allele and Chlamydial infection was highly associated with schizophrenia in a German population, which prompted us to investigate whether the HLA-A gene was also associated with schizophrenia in our population. Using a sequencing-based HLA typing method, we determined the HLA-A genotypes in 377 Han Chinese patients with schizophrenia (214 males, 163 females) and 321 non-psychotic Han Chinese control subjects (164 males, 157 females) from Taiwan. In total, 26 DNA-defined HLA-A alleles were identified in this sample. However, no significant differences of these allelic frequencies were found between the patients and the control subjects, suggesting that the HLA-A gene was unlikely a major risk factor of schizophrenia in this sample. As different populations have different HLA polymorphisms, an examination of the relationship of other HLA genes and schizophrenia in our population, with a larger sample size, is warranted in the future.  相似文献   
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