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排序方式: 共有711条查询结果,搜索用时 15 毫秒
631.
We retrospectively analyzed the medical records and clinical characteristics of 15 patients diagnosed with Penicilliosis marneffei (PSM) between January 1, 1993, and December 31, 2012, at the Third Affiliated Hospital of Sun Yat-sen University. The most common symptoms of PSM were fever (14/15, 93 %), cough (13/15, 87 %), and sputum production (6/15, 40 %), weight loss (14/15, 60 %), lymph node enlargement (9/15, 60 %), hepatosplenomegaly (7/15, 47 %), anemia (7/15, 47 %), and hemoptysis (4/15, 26 %). The most common underlying diseases in patients diagnosed with PSM were AIDS (9/15, 60 %), post-organ transplantation (3/15, 20 %), rheumatic autoimmune disease (2/15, 13 %), and hematological malignancy (1/15, 7 %). All patients, except those with AIDS, were treated with immunosuppressant drugs. White blood cell counts were increased in 10/15 (67 %) patients, while hemoglobin concentrations were decreased in 8/15 (53 %) patients. The ratios of CD4+/total T lymphocytes and CD4+/CD8+ T lymphocytes declined in all the 11 test cases. Nodular lesions or masses were the most common anomalies detected during computed tomography scans, but disseminated inflammation and interstitial changes were also seen. Clinical samples with positive culture results were obtained from sputum or secretions obtained by bronchoscopy, venous blood, percutaneous pulmonary puncture, bone marrow, or skin lesions. Between 1993 and 2003, only four cases of PSM, all connected with AIDS, were diagnosed, while 11 cases of PSM, with or without concurrent AIDS, were diagnosed between 2003 and 2012. Amphotericin B was used to control the disease in some cases. In conclusion, the occurrence of PSM, especially in patients without concurrent AIDS, has increased. The early culture of Penicillium marneffei from clinical samples is critical for correct diagnosis of PSM, and amphotericin B is recommended as the first choice for treatment.  相似文献   
632.
633.
目的:探讨单体位左胸左颈两切口的手术方式在外科治疗食管上段癌中的应用效果。方法:选择2008年1月至2012年4月间我院收治的食管上段癌患者49例,根据手术方法分为研究组(n=19)和对照组(n=30),研究组行单体位左胸左颈两切口管型吻合器治疗,对照组行传统颈、胸、腹三切口方法治疗。观察两组手术时间、术中出血量、清扫淋巴结数、术后引流量和术后并发症等。结果:研究组手术时间显著短于对照组,术中出血量和术后引流量显著低于对照组(P0.05)。两组清扫淋巴结数比较无统计学差异(P0.05)。两组患者均全部治愈出院,研究组肺不张、反流性食管炎、吻合口瘘、吻合口狭窄等发生率显著低于对照组(P0.05)。结论:单体位左胸左颈两切口管型吻合器治疗食管上段癌安全,可靠,省时易行,是一种较好的手术方式,值得推广。  相似文献   
634.
The small heat shock protein IbpB of Escherichia coli can accelerate protein disaggregation from inclusion body by Hsp100-Hsp70 re-activation system in vitro. It was therefore hypothesized that overexpression of IbpB might be able to promote protein disaggregation from inclusion body, by which more soluble recombinant proteins would be obtained. The overexpression of IbpB actually enhanced production of more active soluble XynB of Streptomyces olivaceovirdis in E. coli BL21(DE3). Surprisingly, the disaggregation of XynB from inclusion body was not accelerated. It seemed that the overexpressed IbpB protected improperly or partially folded XynB from aggregation and mediated the subsequent refolding. These results show potential of improving production of active heterologous proteins in E. coli.  相似文献   
635.
636.
Yang QH  Xu JN  Zhang R  Gao L  Xu RK 《中国应用生理学杂志》2006,22(2):174-178,i0002
目的:探讨褪黑素(melatonin,MLT)抑制17-β-雌二醇(17-β-estradiol,E2)诱发垂体催乳素(prolactin,PRL)瘤的增生及其机制的初始阶段,MLT对雌激素受体的作用。方法:在体实验采用每日定时给各组SD大鼠分别皮下注射不同浓度的MLT,建立MLT抑制E2诱发的垂体PRL瘤增生的动物模型。离体实验采用原代培养细胞原位杂交方法,探讨垂体PRL瘤细胞MLT受体的表达、MLT对雌激素受体(ER)表达的作用;应用电泳迁移率改变(EMSA)的方法,观察MLT对雌激素受体(ER)与雌激素反应元件(ERE)结合的效应。结果:每只大鼠每日定时皮下注射0.25或0.50mg MLT能显著抑制E2诱发的垂体PRL瘤的增生(分别P〈0.01、P〈0.05);F4诱发的垂体PRL瘤细胞内有MLT受体MLT1a和MLT1b;给0.25mg/day/rat MLT组的大鼠垂体PRL瘤细胞内ER的表达显著减少(P〈0.01)、ER与ERE的结合量显著降低(P〈0.01)。结论:一定剂量的MLT能显著抑制E2诱发的SD大鼠垂体PRL瘤的增生,其作用机制之一可能与MLT抑制ER的表达、及其部分阻断ER与ERE的结合有关。  相似文献   
637.
Matrix metallopeptidase-9 (MMP-9) plays a pivotal role in vascular remodeling and development of atherosclerotic lesion. The potentially functional MMP-9 polymorphisms may contribute to the susceptibility of coronary artery disease (CAD). A case–control study composed of 762 CAD cases and 555 CAD-free controls was conducted in a Chinese population to investigate the association between the MMP-9 ?1562 C>T, R279Q, P574R and R668Q polymorphisms and CAD risk. It was found that the variant genotypes of R279Q, P574R and R668Q were associated with a non-significant decreased risk of CAD when compared with their wild-type genotypes, respectively, Furthermore, compared with those without any variant genotypes for these four nonsynonymouse loci, individuals carrying all four variant genotypes (?1562 CT/TT, 279 RQ/QQ, 574 PR/RR and 668 RQ/QQ) had a 51% decreased risk of CAD (adjusted OR = 0.49; 95% CI = 0.26–0.95, P = 0.033). Although no significant main effects were observed for MMP-9 ?1562 C>T locus on CAD risk, variant genotypes of ?1562 C>T were associated with a 2.53 increased risk of CAD in subjects with diabetes mellitus (DM) (95% CI = 1.18–5.45, P = 0.018). In CAD cases, variant genotypes of ?1562 C>T were associated with a significantly increased risk of MI (adjusted OR, 1.48, 95% CI, 1.01–2.20, P = 0.048). These findings suggest that MMP-9 R279Q, P574R and R668Q may have combined effect in the occurrence of CAD and ?1562 CT/TT genotypes may contribute to CAD in diabetics and MI in CAD patients.  相似文献   
638.
Periodontitis is a prevalent chronic inflammatory disease. Circular RNAs (circRNAs) have been revealed to play roles in the inflammatory response. Hence, this work aimed to explore the role and mechanism of circ_0062491 in periodontitis progression. Human periodontal ligament cells (PDLCs) were isolated from the periodontal ligament (PDL) of the healthy teeth with orthodontic requirement after tooth extraction. In vitro experiments were conducted by cell counting Kit-8 (CCK-8) assay, flow cytometry, Western blot, and ELISA to determine cell viability, apoptosis, and inflammatory response. The binding between miR-498 and circ_0062491 or SOCS6 was confirmed using dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. Circ_0062491 expression was decreased in periodontitis and LPS-induced PDLCs. Restoration of circ_0062491 attenuated LPS-induced apoptosis and inflammation in PDLCs in vitro. Mechanistically, circ_0062491 functioned as a sponge for miR-498, and miR-498 directly targeted SOCS6. Rescue experiments showed that miR-498 up-regulation reversed the protective action of circ_0062491 on PDLCs under LPS treatment. Moreover, silencing of miR-498 protected PDLCs from LPS-induced apoptosis and inflammation, which were abolished by SOCS6 knockdown. Circ_0062491 protected PDLCs from LPS-induced apoptosis and inflammation, suggesting a new target for the amelioration of periodontitis patients.  相似文献   
639.
In recent years, with the increase in cancer mortality caused by metastasis, and with the development of individualized and precise medical treatment, early diagnosis with precision becomes the key to decrease the death rate. Since detecting tumour biomarkers in body fluids is the most non‐invasive way to identify the status of tumour development, it has been widely investigated for the usage in clinic. These biomarkers include different expression or mutation in microRNAs (miRNAs), circulating tumour DNAs (ctDNAs), proteins, exosomes and circulating tumour cells (CTCs). In the present article, we summarized and discussed some updated research on these biomarkers. We overviewed their biological functions and evaluated their multiple roles in human and small animal clinical treatment, including diagnosis of cancers, classification of cancers, prognostic and predictive values for therapy response, monitors for therapy efficacy, and anti‐cancer therapeutics. Biomarkers including different expression or mutation in miRNAs, ctDNAs, proteins, exosomes and CTCs provide more choice for early diagnosis of tumour detection at early stage before metastasis. Combination detection of these tumour biomarkers may provide higher accuracy at the lowest molecule combination number for tumour early detection. Moreover, tumour biomarkers can provide valuable suggestions for clinical anti‐cancer treatment and execute monitoring of treatment efficiency.  相似文献   
640.
目的:构建有效的小鼠神经粘附分子(NCAMl40)基因的RNA干扰(RNAi)质粒载体,为研究NCAMl40参与的细胞信号通j咯转导、其生物学作用以及以NCAMl40为靶点的基因治疗提供稳定转染的RNAi质粒。方法:使用基因序列软件设计、筛选符合公开文献筛选参数的4条靶序列以及1条阴性对照序列,由上海吉玛技术有限公司合成。与载体质粒pGPU6/GFP/Neo重组后.分别命名为pSi—ncal、pSi—nca2、pSi-nca3、pSi—nca4和pSi—control。转染大肠杆菌感受态细胞。选择阳性克隆进行DNA测序鉴定,、qCestemblot方法进行干扰靶点的筛选。选取干扰效率最高的质粒转染MN9D细胞,普通光学显微镜分别计数同一视野细胞总数及GFP阳性细胞数,计算转染效率。结果:酶切和DNA测序结果证实shRNA正确插入pGPU6/GFP/Neo质粒;Westernblot结果显示与空质粒对照组比较,pSi—nca4组细胞NCAMl40表达明显下调,细胞转染效率为62%。结论:成功构建靶向小鼠NCAMl40基因的RNAi质粒,为NCAMl40参与的细胞信号通路的研究以及以NCAMl40为靶点的基因治疗提供了稳定转染:细胞的干扰质粒,为研究其生物学作用奠定了分子生物学基础。  相似文献   
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