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32.
Quantification of facial skeletal shape variation in fibroblast growth factor receptor‐related craniosynostosis syndromes 下载免费PDF全文
33.
目的:探讨治疗腹膜后血肿的临床疗效。方法:对腹膜后血肿106例分型、诊断及治疗进行了回顾性分析。结果:腹膜后血肿无特异性症状和体征,可通过休克、腹穿、放射、超声波、尿路及血管造影等提高诊断,手术79例,非手术19例,死亡8例。结论:对腹膜后血肿的早期诊断及救治是提高生存率的关键。 相似文献
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Serum magnesium concentration was measured in 80 adult patients (age range: 18–40 yr) presenting with acute, uncomplicated
falciparum malaria infection and a control group of 20 age-matched, healthy individuals. The mean serum magnesium concentration in the
patients was 1950.0 ±10.0 μg/dL. The control serum magnesium was 640.0±40.0 μg/dL. This represents an over threefold increase
in serum magnesium levels above normal value, p<0.01. The key pathogenic event in acute falciparum malaria infection is the hemolysis of both infected and uninfected red blood cells. Therefore, the increased serum magnesium
concentration might occur because of the hemolysis arising from erythrocytic merogony because red blood cells contain high
amounts of magnesium. In conclusion, the increased serum magnesium has potential application as a biomarker of acute falciparum malaria infection in adults. 相似文献
36.
John E. Moore Yasunori Maeda Jiru Xu B. Cherie Millar Peter H. Herold V. M. J. Browne-Lauwers Colin E. Goldsmith Anne Loughrey Paul J. Rooney J. Stuart Elborn Motoo Matsuda 《World journal of microbiology & biotechnology》2008,24(7):1227-1232
To employ 16S rDNA PCR and automated sequencing techniques to identify a collection of bacterial veterinary pathogens from
avian, equine, canine and ovine sources, that have proven difficult to identify, employing conventional cultural techniques.
Universal or “broad-range” eubacterial PCR was performed on a collection of 46 difficult-to-identify bacterial isolates originating
from clinical veterinary specimens. 16S rDNA PCR was performed using two sets of universal primers to successfully generate
a composite amplicon of 1,068 bp, which was sequenced to obtain each isolate’s identity. Sequence analysis was able to identify
all isolates examined with relative ease. Where the use of molecular identification methods is justified, such as in outbreak
control or bioterrorism in animal health, employment of partial 16S rDNA PCR and sequencing employing universal or “broad-range”
16S rDNA, provides a valuable and reliable method of identification of such pathogens. 相似文献
37.
APOBEC(“载脂蛋白质B mRNA编辑催化多肽”)是一类进化保守的胞苷脱氨酶家族。在人体内,已知含有保守的DNA胞嘧啶脱氨酶结构域的基因共有11种,包括AID、APOBEC1、APOBEC2、APOBEC3基因家族APOBEC3A、APOBEC3B、APOBEC3C、APOBEC3DE、APOBEC3F、APOBEC3G、APOBEC3H(分别称为A3A、A3B、A3C、A3D、A3F、A3G和A3H)和APOBEC4。APOBEC利用其脱氨酶活性通过与RNA和/或DNA结合,催化mRNA或使DNA中的胞嘧啶核苷酸转变为尿嘧啶,或者胞嘧啶核苷酸转变为胸腺嘧啶核苷酸,进而完成各自不同的功能。目前研究发现,AID及APOBEC3(A3s)的7种脱氨酶在人类的天然免疫和适应性免疫防御过程中发挥重要的作用,且在口腔癌,肺癌(腺癌和鳞状细胞癌),结直肠癌和乳腺癌等的诊疗过程中具有重要的潜在应用价值。AID可以通过将胞嘧啶脱氨基成尿嘧啶,来启动SHM (体细胞超突变)和CSR (类别转换重组),进而在抗体多样性方面发挥作用。它的异常表达能够使B细胞淋巴瘤等恶性肿瘤的发病频率显著增加。而A3A、A3B通过胞嘧啶到尿嘧啶转换,以及自身表达量上调而在乳腺癌和肺癌诊疗中起作用。A3G通过APOBEC3G/miR 29/MMP2为了解结直肠癌肝转移和开发治疗晚期结肠癌的有效疗法开辟了新的途径。综上所述,本文将以AID,A3A,A3B,A3G为例子,对APOBEC在癌症诊断和治疗方面的应用进行综述,以期为进一步药物研究和临床应用等提供参考。 相似文献
38.
Francois Korbmacher Benjamin Drepper Theo Sanderson Peer Martin Thomas Stach Alexander G. Maier Kai Matuschewski Joachim M. Matz 《Cellular microbiology》2021,23(1)
Malaria parasites are fast replicating unicellular organisms and require substantial amounts of folate for DNA synthesis. Despite the central role of this critical co‐factor for parasite survival, only little is known about intraparasitic folate trafficking in Plasmodium. Here, we report on the expression, subcellular localisation and function of the parasite's folate transporter 2 (FT2) during life cycle progression in the murine malaria parasite Plasmodium berghei. Using live fluorescence microscopy of genetically engineered parasites, we demonstrate that FT2 localises to the apicoplast. In invasive P. berghei stages, a fraction of FT2 is also observed at the apical end. Upon genetic disruption of FT2, blood and liver infection, gametocyte production and mosquito colonisation remain unaltered. But in the Anopheles vector, FT2‐deficient parasites develop inflated oocysts with unusual pulp formation consisting of numerous single‐membrane vesicles, which ultimately fuse to form large cavities. Ultrastructural analysis suggests that this defect reflects aberrant sporoblast formation caused by abnormal vesicular traffic. Complete sporogony in FT2‐deficient oocysts is very rare, and mutant sporozoites fail to establish hepatocyte infection, resulting in a complete block of parasite transmission. Our findings reveal a previously unrecognised organellar folate transporter that exerts critical roles for pathogen maturation in the arthropod vector. 相似文献
39.
Specific primers and the polymerase chain reaction (PCR) are increasingly used for detection of fungi in plants. Detection depends on isolation of DNA that is free of compounds that inhibit amplification. We report on the significance of inhibition in soybean stems with a focus on studies of the vascular fungal pathogen Phialophora gregata. A simple DNA extraction procedure based on a FastDNA® kit is described that allows consistent detection of fungi in soybean stems using PCR. The addition of polyvinylpyrrolidone and supplemental DNA purification steps overcame inhibition in over 90% of samples. These methods should also facilitate studies with other plant and fungal species. 相似文献
40.
《IRBM》2021,42(5):345-352
Available clinical methods for heart failure (HF) diagnosis are expensive and require a high-level of experts intervention. Recently, various machine learning models have been developed for the prediction of HF where most of them have an issue of over-fitting. Over-fitting occurs when machine learning based predictive models show better performance on the training data yet demonstrate a poor performance on the testing data and the other way around. Developing a machine learning model which is able to produce generalization capabilities (such that the model exhibits better performance on both the training and the testing data sets) could overall minimize the prediction errors. Hence, such prediction models could potentially be helpful to cardiologists for the effective diagnose of HF. This paper proposes a two-stage decision support system to overcome the over-fitting issue and to optimize the generalization factor. The first stage uses a mutual information based statistical model while the second stage uses a neural network. We applied our approach to the HF subset of publicly available Cleveland heart disease database. Our experimental results show that the proposed decision support system has optimized the generalization capabilities and has reduced the mean percent error (MPE) to 8.8% which is significantly less than the recently published studies. In addition, our model exhibits a 93.33% accuracy rate which is higher than twenty eight recently developed HF risk prediction models that achieved accuracy in the range of 57.85% to 92.31%. We can hope that our decision support system will be helpful to cardiologists if deployed in clinical setup. 相似文献