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141.
Aim: Although obesity and weight gain generally are anticipated to be caused by an imbalance between energy intake and energy expenditure, the significance of thyroid hormones (TH) remains unclear. Examination of mitochondrial function may reflect intracellular thyroid hormone effect and elucidate whether a lower metabolic rate is present. Methods: In a group of 34 obese adolescents (age <16 years and body mass index above the age‐related 95th percentile), and an age‐ and gender‐matched group of 32 lean adolescent, thyroid stimulating hormone (TSH) and basal oxygen consumption were measured and mitochondrial function in peripheral blood monocytes was determined by flow cytometry. Results: Significant increase in TSH (3.06 ± 1.56 mU/L vs. 2.33 ± 0.91 mU/L, p < 0.05) and a decrease in VO2 (129 ± 16 mL O2/m2*min vs. 146 ± 15 mL O2/m2*min, p < 0.05) were observed in obese adolescents compared with lean adolescents. Flow cytometry analysis demonstrated a lower mitochondrial mass (6385 ± 1962 a.u. vs. 7608 ± 2328 a.u., p < 0.05) and mitochondrial membrane potential (11426 ± 3861 a.u. vs. 14017 ± 5536 a.u., p < 0.05) in obese adolescents compared with lean adolescents. These results are even more pronounced in adolescents with obese mothers. Conclusion: In obese adolescents, the increased TSH and lowered VO2 propose a lowered basal metabolic rate and the impaired mitochondrial function suggests a decreased thyroid hormone stimulation of mitochondrial energy production. The maternal in‐heritage is suggestive of a basal metabolic defect or mitochondrial resistance for TH. 相似文献
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143.
不同氮量全胃肠外营养支持对脓毒症病人蛋白质代谢的影响 总被引:2,自引:0,他引:2
如何提高脓毒症闰人营养支持的效果是当前的热点和难点之一。本实验前瞻性地对比观察了不同蛋白质供应负荷0.25g/V(kg.d)vs0.35gN/(kg.d),在脓毒症病人全有肠外营养支持中对蛋白质代谢状况的影响。结果发现,与低氮量TPN相比,高氮量TPN支持可改善血浆蛋白水平,增加累积氮平衡,但尿中3-MH排出量也有相应增加。 相似文献
144.
Mammography with synchrotron radiation 总被引:2,自引:0,他引:2
145.
PL Macken FRACO FRACS SR Boyd MD I Campbell MD CRCP DipBact † D Chang MSc † DS Rootman MD FRCS GE Trope PhD FRCS 《Clinical & experimental ophthalmology》1995,23(4):323-325
Background: Haemophilus aphrophilus is a rare cause of ocular infection. It has been reported once as a cause of late-onset endophthalmitis in a patient with an inadvertent bleb after cataract surgery. We present a case of Haemophilus aphrophilus bleb infection after a mitomycin trabeculectomy.
Methods: A 56-year-old woman presented with a bleb infection 10 weeks after a mitomycin C augmented trabeculectomy at a University tertiary referral practice of one of the authors (GET). The causative organism was Haemophilus aphrophilus , identified by the Toronto Public Health Laboratory, Ontario, Canada.
Results: The bleb infection resolved following topical, subconjunctival and intravenous antibiotic therapy. A formal bleb revision was required to repair a persistent bleb leak.
Conclusion: Patients who have had trabeculectomies augmented with mitomycin C may be predisposed to bleb infection with unusual organisms. Prompt diagnosis and treatment is necessary to control the infection. Increased awareness and communication with laboratory personnel may increase the isolation of this fastidious organism. 相似文献
Methods: A 56-year-old woman presented with a bleb infection 10 weeks after a mitomycin C augmented trabeculectomy at a University tertiary referral practice of one of the authors (GET). The causative organism was Haemophilus aphrophilus , identified by the Toronto Public Health Laboratory, Ontario, Canada.
Results: The bleb infection resolved following topical, subconjunctival and intravenous antibiotic therapy. A formal bleb revision was required to repair a persistent bleb leak.
Conclusion: Patients who have had trabeculectomies augmented with mitomycin C may be predisposed to bleb infection with unusual organisms. Prompt diagnosis and treatment is necessary to control the infection. Increased awareness and communication with laboratory personnel may increase the isolation of this fastidious organism. 相似文献
146.
147.
目的 :用基因重组技术表达人亲环素 A( Cy PA) ,以避免从人组织材料中提取纯化该蛋白的麻烦。 方法 :应用反转录聚合酶链反应 ( RT- PCR)技术从人淋巴细胞系 ( MT4 )总 RNA中扩增得到 Cy PA基因片段 ,并用重组 DNA技术对该基因片段进行克隆 ,构建表达载体 ,转入大肠杆菌进行表达。 结果 :DNA序列分析表明 ,得到的基因片段与设计编码 Cy PA的结构基因序列完全相同。所构建的表达载体 p ET11/Cy PA转入大肠杆菌获得表达 ,重组蛋白表达量占菌体可溶性蛋白的 4 1% ,经测定具有肽基脯氨酸顺 /反异构酶活性。 结论 :利用基因重组技术使大肠杆菌高效表达出有生物活性的人 Cy PA。 相似文献
148.
The population diversity of Bangladeshi begomoviruses and their vector, Bemisia tabaci was analysed by PCR-based detection and partial genome sequencing. B. tabaci adults and plants expressing symptoms of virus infection were collected from locations representing diverse agro-ecological
regions of the country. Universal and species-specific primers were used to detect begomoviruses in seven crops (chilli, okra,
papaya, pumpkin, sponge gourd, tomato and yardlong bean) and two common weeds (Ageratum conyzoides and Croton bonplandianum). At least five distinct species of tomato leaf curl viruses infected tomato and other host-plants. Phylogenetic analyses
of their nucleotide sequences (∼530 bases) from the intergenic region and capsid protein of DNA-A indicated the existence
of five distinct clusters of begomoviruses. Begomoviruses infecting tomato, chilli and dolichos have been reported previously,
and those infecting Ageratum, Croton, okra, papaya, pumpkin and yardlong bean are described for the first time. Phylogenetic analyses based on mitochondrial cytochrome
oxidase I gene sequences of 21 B. tabaci from Bangladesh and other reference sequences grouped them into at least two independent clusters. Some sequences from different
countries, e.g., Bangladesh, China, India, Nepal, Pakistan and Thailand were almost identical while others collected from
plants within the same field diverged by as much as 15%, indicating high diversity even at the local level. None of the B. tabaci from Bangladesh grouped with the reference B- and Q-biotype sequences, thus these two aggressive biotypes were apparently
absent from Bangladesh. 相似文献
149.
Devi KR Narain K Bhattacharya S Negmu K Agatsuma T Blair D Wickramashinghe S Mahanta J 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2007,101(8):786-792
In the northeastern region of India, paragonimiasis is emerging as an important public health problem. However, until now the identity of the species causing human infection has been uncertain and there has been little information on the prevalence and clinicoradiological features of infection in the community. Parasitological and immunological surveys revealed that paragonimiasis was hyperendemic in parts of Arunachal Pradesh. Egg positivity in the sputum was 20.9% and 4.1% in children (age =15 years) and adults (age >15 years), respectively. Antibody positivity against excretory-secretory antigen of the adult worm in children and adults was 51.7% and 18.7%, respectively. Chronic cough (97.2%) and haemoptysis (83.3%) were common respiratory symptoms among egg-positive cases. Chest radiography (n=68) images from egg-positive cases showed that air space consolidation (75%), cavitary lesions (14.7%) and mediastinal adenopathy (11.8%) were very frequent. Less frequent findings were nodular lesions, bronchiectasis, mediastinal adenopathy, pleural thickening and pleural effusion. DNA extracted from eggs from the sputum of patients from Arunachal Pradesh was sequenced. Analyses of the second internal transcribed spacer (ITS2) of nuclear rDNA revealed that the species responsible is Paragonimus heterotremus. 相似文献
150.
PJ Smith ; TE Miller ; J Fraser ; JW Smith ; JR Svirbely ; S Rudmann ; PL Strohm ; M Kennedy 《Transfusion》1991,31(4):313-317
Four empirical studies were conducted for better understanding of the nature of problem-solving activities by medical technologists and medical technology students when performing antibody identification tasks. The results indicated the importance of strategies that ensure the collection of converging evidence, as these strategies protect against the fallibility of commonly used heuristics and against errors due to simple slips. The results also indicate that not only do students make significant numbers of errors, but so do practicing technologists. In one of the studies covering a 1-year period, for instance, a group of 16 technologists made a total of 41 errors in 1057 cases. On the basis of these findings, several alternatives are proposed to reduce errors. 相似文献