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61.
目的探讨瘦素质量浓度与早期静脉营养及生长发育的关系。方法新疆医科大学第一附属医院新生儿科于2005-01—2006-02,将收治的86例早产适于胎龄儿用随机数字表法分为观察组(早期微量喂养同时辅助胃肠外营养组)45例和对照组(单纯早期微量喂养组)47例,分别测定脐血及第7天血清瘦素质量浓度,同时监测营养状况和生长发育指标,并作对比分析。结果(1)观察组与对照组脐血瘦素质量浓度分别为(4.6±3.7)ng/mL、(4.8±2.2)ng/mL,生后第7天两组瘦素质量浓度分别为(4.3±2.2)ng/mL、(3.1±1.7)ng/mL。对照组第7天血清瘦素质量浓度明显低于脐血(P<0.05),而观察组其差异无统计学意义(P>0.05)。(2)脐血瘦素质量浓度与出生体重、胎龄成正相关(r=0.56、r=0.67)。(3)观察组第7天热卡及蛋白质摄入量、血清瘦素质量浓度、皮褶厚度变化值与对照组相比,差异有统计学意义(P<0.05)。结论对早产儿应尽早喂养,同时需要胃肠外营养作为肠内营养的补充。瘦素可作为新生儿营养效果判定的实验室指标之一。  相似文献   
62.
Isolated deletions of the long arm of chromosome 5, del(5q), are observed in 10% of myelodysplastic syndromes (MDS) and are associated with a more favorable prognosis, although the clinical course varies considerably. If one or more additional chromosomal aberrations are present, this correlates with a significantly shorter overall survival. To assess the frequency of hidden abnormalities in cases with an isolated cytogenetic del(5q), we have performed a genome wide high resolution 44 K 60mer oligonucleotide array comparative genomic hybridization (aCGH) study using DNA from bone marrow cells of 12 MDS and one AML patient. In one case a single additional hidden 5.6 Mb deletion of 13q14 and in another case multiple larger aberrations involving many chromosomes were found. Fluorescence in situ hybridization demonstrated that aberrations present in 35% of the bone marrow cells can be detected by aCGH. Furthermore with oligonucleotide aCGH the deletion end points in 5q were mapped precisely, revealing a cluster of proximal breakpoints in band q14.3 (n = 8) and a distal cluster between bands q33.2 and q34 (n = 11). This study shows the high resolution of oligonucleotide CGH arrays for precisely mapping genomic alterations and for refinement of deletion end points. In addition, the high sensitivity of this method enables the study of whole bone marrow cells from MDS patients, a disease with a low blast count.  相似文献   
63.
Studies in gene-targeted mice have demonstrated that factor B of the alternative complement pathway plays an important role in several disease models, but an exogenous inhibitor of factor B has not previously been available. We have developed an inhibitory monoclonal antibody directed against a critical epitope on mouse factor B and have tested it in a model of antiphospholipid (aPL) antibody (Ab)-induced fetal loss. Gene-targeted factor B-deficient mice (fB-/-) were injected with a fusion protein comprised of the second and third short consensus repeat (SCR) domains of mouse factor B linked to a mouse IgG1 Fc domain. Hybridomas were made from splenocytes of the immunized mouse. One mAb, designated 1379, produced an IgG1 antibody that inhibited alternative pathway activation in vitro and in vivo by preventing formation of the C3bBb complex. Strikingly, this mAb inhibited alternative pathway activation in serum from mice, rats, humans, monkeys, pigs and horses. Fab fragments made from this mAb also inhibited alternative pathway activation. Epitope mapping demonstrated that this antibody binds to factor B within the third SCR domain. When mAb 1379 was administered to mice that also received human IgG containing antiphospholipid antibodies, it provided significant protection from antiphospholipid antibody-induced complement activation and fetal loss. Thus, this mAb to factor B has broad species reactivity and effectively inhibits alternative pathway activation. The mAb protects mice in an in vivo model of antiphospholipid antibody syndrome, demonstrating the therapeutic potential for the inhibition of factor B in this disease.  相似文献   
64.
Factors involved in the stability of trinucleotide repeats during transmission were studied in 139 families in which a full mutation, premutation or intermediate allele at either FRAXA or FRAXE was segregating. The transmission of alleles at FRAXA, FRAXE and four microsatellite loci were recorded for all individuals. Instability within the minimal and common ranges (0-40 repeats for FRAXA, 0-30 repeats for FRAXE) was extremely rare; only one example was observed, an increased in size at FRAXA from 29 to 39 repeats. Four FRAXA and three FRAXE alleles in the intermediate range (41-60) repeats for FRAXA, 31-60 for FRAXE) were unstably transmitted. Instability was more frequent for FRAXA intermediate alleles that had a tract of pure CGG greater than 37 although instability only occurred in two of 13 such transmissions: the changes observed were limited to only one or two repeats. Premutation FRAXA alleles over 100 repeats expanded to a full mutation during female transmission in 100% of cases, in agreement with other published series. There was no clear correlation between haplotype and probability of expansion of FRAXA premutations. Instability at FRAXA or FRAXE was more often observed in conjunction with a second instability at an independent locus suggesting genomic instability as a possible mechanism by which at least some FRAXA and FRAXE mutations arise.   相似文献   
65.
Evidence for superantigenic activity during murine malaria infection   总被引:2,自引:0,他引:2  
TCR V beta usage was examined in C57BL/6 mice infected with Plasmodium yoelii. In addition to a polyclonal T cell activation, already described, a superantigenic-like activity was observed during the acute infection. This superantigenic activity induces a preferential deletion without prior expansion of CD4+ and CD8+ T cells bearing the TCR V beta 9 segment. The superantigen could be released by the parasite at different stages of its development since the deletion of V beta 9+ T cells was observed in blood and lymph nodes of mice infected either with sporozoites or with erythrocytic stages. Injection of sporozoite or parasitized erythrocytes to newborn mice led to a deletion and anergy of peripheral V beta 9+ T cells, without affecting thymic T cell populations. These observations suggest that the superantigen is released at very low concentrations during parasite development. The role of such parasite superantigenic activity in infectivity can be underlined by the observation that congenic BALB.D2 Mis1a mice lacking V beta 9 T cells are more susceptible to infection by P. yoelii.   相似文献   
66.
67.
El‐Hattab AW, Bournat J, Eng PA, Wu JBS, Walker BA, Stankiewicz P, Cheung SW, Brown CW. Microduplication of Xp11.23p11.3 with effects on cognition, behavior, and craniofacial development. We report an ~1.3 Mb tandem duplication at Xp11.23p11.3 in an 11‐year‐old boy with pleasant personality, hyperactivity, learning and visual‐spatial difficulties, relative microcephaly, long face, stellate iris pattern, and periorbital fullness. This clinical presentation is milder and distinct from that of patients with partially overlapping Xp11.22p11.23 duplications which have been described in males and females with intellectual disability, language delay, autistic behaviors, and seizures. The duplicated region harbors three known X‐linked mental retardation genes: FTSJ1, ZNF81, and SYN1. Quantitative polymerase chain reaction from whole blood total RNA showed increased expression of three genes located in the duplicated region: EBP, WDR13, and ZNF81. Thus, over‐expression of genes in the interval may contribute to the observed phenotype. Many of the features seen in this patient are present in individuals with Williams‐Beuren syndrome (WBS). Interestingly, the SYN1 gene within the duplicated interval, as well as the STX1A gene, within the WBS critical region, co‐localize to presynaptic active zones, and play important roles in neurotransmitter release.  相似文献   
68.
69.

Background

The increased reports of ESBL dissemination from various centres in south western, Nigeria and the recent emergence of carbapenem resistant bacteria prompted the conception of this study.

Objectives

To demonstrate the relationship between high molecular weight plasmids and the expression of antibiotic multi-resistance including ESBL and carbapenemase.

Methods

We investigated 97 isolates of selected organisms consisting of 67 E. coli and 30 Klebseilla spp for the presence of plasmids expressing ESBL including carbapenem-hydrolysing enzymes. Beta-lactamase was determined using acidometric method, while ESBL and carbapenemase activity was determined using the double-disk diffusion test as well as the Modified Hodge test (MHT). Plasmid profiles of ESBL and carbapenemase positive isolates were determined according to standard protocols.

Results

An ESBL prevalence rate of 21.6% and carbapenem- resistance rate of 9.3% was recorded. Antibiotic susceptibility profile of ESBL isolates showed 100.0% resistance against Amoxicillin, Cotrimoxazole and Erythromycin. Moderate susceptibility was recorded against the Quinolone class of antibiotics; Meropenem remained the most active antibiotic against ESBL isolates with 62.5% against E. coli and 60% against K. pneumoniae. The plasmid profiles of our study isolates ranged from 11.8kbp to 35.5kbp.

Conclusion

Due to the relationship between high molecular weight plasmids and multi-drug resistance, we hereby recommend regular molecular surveillance of this form in our study setting.  相似文献   
70.
Objectives: To screen for potentially underreported behavioral changes in patients with idiopathic Parkinson's disease (PD) pre‐ and post‐deep brain stimulation (DBS), a retrospective data base review was performed. Methods: In total, 113 patients who underwent unilateral or bilateral DBS at the University of Florida in either subthalamic nucleus or globus pallidus internus for PD were screened for behavioral issues by asking about the presence or absence of seven neuropsychiatric symptoms (panic, fear, paranoia, anger, suicidal flashes, crying, and laughing). Results: There was a high prevalence of fear (16.3%), panic (14.0%), and anger (11.6%) at baseline in this cohort. In the first six months following DBS implantation, anger (32.6%), fear (26.7%), and uncontrollable crying (26.7%) were the most frequent symptoms reported. Those symptoms also were present following six months of DBS surgery (30.2%, 29.1%, and 19.8%, respectively). New uncontrollable crying occurred more in the acute postoperative stage (less than or equal to six months) (p= 0.033), while new anger occurred more in the chronic postoperative stage (greater than six months) (p= 0.017). The frequency of uncontrollable laughing significantly increased with bilateral DBS (p= 0.033). Conclusions: Many of the neuropsychiatric issues were identified at preoperative baseline and their overall occurrence was more than expected. There was a potential for worsening of these issues post‐DBS. There were subtle differences in time course, and in unilateral vs. bilateral implantations. Clinicians should be aware of these potential behavioral issues that may emerge following DBS therapy, and should consider including screening questions in preoperative and postoperative interviews. Standardized scales may miss the presence or absence of these clinically relevant issues.  相似文献   
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