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排序方式: 共有145条查询结果,搜索用时 15 毫秒
1.
S Filipecki B Vertun-Baranowska J Müller W Pokojski B Hajduk A Radomyski W Tomkowski P Ko?b Z Polowiec 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1989,44(2-3):36-41
Controlled oxygen-therapy was used in 30 out of 49 patients (61%) with the acute respiratory failure or exacerbations of the chronic respiratory failure treated at ICU (Group Y), while artificial ventilation in the remaining 19 patients (39%; Group B). An improvement was achieved in 70% of patients of Group A and 42% in Group B. Overall improvement was achieved in 59% of the treated patients. There were 69% of treated patients with infections. Totally 41% of the treated patients died (30% of Group A and 58% of Group B). An analysis of the results has been carried out in various subgroups of the treated patients, i.e. the acute and exacerbated respiratory failure as well as partial and complete respiratory insufficiency. The result of high risk patients have also been analysed. This subgroup included sudden cardiac arrest, shock and non-compensated acidosis. Favourable effects of the intensive care of patients with infections have been discussed with particular reference to the life hazard in case of septic complications. Emphasis is on the unfavorable effects of therapy in patients with respiratory failure complicated with pulmonary embolism. Indications to the use of respirator and complications of the artificial ventilation have been discussed. 相似文献
2.
Hardies SC; Martin SL; Voliva CF; Hutchison CA d; Edgell MH 《Molecular biology and evolution》1986,3(2):109-125
3.
S L Hajduk D R Moore J Vasudevacharya H Siqueira A F Torri E M Tytler J D Esko 《The Journal of biological chemistry》1989,264(9):5210-5217
Trypanosoma brucei brucei is an important pathogen of domestic cattle in sub-Saharan Africa and is closely related to the human sleeping sickness parasites, Trypanosoma brucei gambiense and Trypanosoma brucei rhodesiense. However, T. b. brucei is non-infectious to humans. The restriction of the host range of T. b. brucei results from the sensitivity of the parasite to lysis by toxic human high density lipoproteins (HDL) (Rifkin, M. R. (1978) Proc. Natl. Acad. Sci. U.S.A. 75, 3450-3454). We show in this report that trypanosome lytic activity is not a universal feature of all human HDL particles but rather that it is associated with a minor subclass of HDL. We have purified the lytic activity about 8,000-fold and have identified and characterized the subspecies of HDL responsible for trypanosome lysis. This class of HDL has a relative molecular weight of 490,000, a buoyant density of 1.21-1.24 g/ml, and a particle diameter of 150-210 A. It contains apolipoproteins AI, AII, CI, CII, and CIII, and monoclonal antibodies against apo-AI and apo-AII inhibit trypanocidal activity. In addition to these common apolipoproteins, the particles also contain at least three unique proteins, as measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under nonreducing conditions. Treatment of the particles with dithiothreitol resulted in the disappearance of two of the proteins and abolished trypanocidal activity. Two-dimensional gel electrophoresis showed that these proteins were a disulfide-linked trimer of 45,000, 36,000, and 13,500-Da polypeptides and dimers of the 36,000- and 13,500-Da polypeptides or of 65,000- and 8,500-Da polypeptides. Studies on the lysis of T. b. brucei by the purified particle suggest that the lytic pathway may involve the uptake of the trypanocidal subspecies of HDL by endocytosis. 相似文献
4.
5.
Yan Lu Shulin/SL Li Shiguo/SG Zhu Yabin/YB Gong Jun/J Shi Ling/ L Xu 《Biological procedures online》2017,19(1):2
DNA/RNA methylation plays an important role in lung cancer initiation and progression. Liquid biopsy makes use of cells, nucleotides and proteins released from tumor cells into body fluids to help with cancer diagnosis and prognosis. Methylation of circulating tumor DNA (ctDNA) has gained increasing attention as biomarkers for lung cancer. Here we briefly introduce the biological basis and detection method of ctDNA methylation, and review various applications of methylated DNA in body fluids in lung cancer screening, diagnosis, prognosis, monitoring and treatment prediction. We also discuss the emerging role of RNA methylation as biomarkers for cancer. 相似文献
6.
JG Hansen W Gao J Dupuis GT O’Connor W Tang M Kowgier A Sood SA Gharib LJ Palmer M Fornage SR Heckbert BM Psaty SL Booth SUNLIGHT Consortium Patricia A Cassano 《Respiratory research》2015,16(1)
Background
Vitamin D is associated with lung function in cross-sectional studies, and vitamin D inadequacy is hypothesized to play a role in the pathogenesis of chronic obstructive pulmonary disease. Further data are needed to clarify the relation between vitamin D status, genetic variation in vitamin D metabolic genes, and cross-sectional and longitudinal changes in lung function in healthy adults.Methods
We estimated the association between serum 25-hydroxyvitamin D [25(OH)D] and cross-sectional forced expiratory volume in the first second (FEV1) in Framingham Heart Study (FHS) Offspring and Third Generation participants and the association between serum 25(OH)D and longitudinal change in FEV1 in Third Generation participants using linear mixed-effects models. Using a gene-based approach, we investigated the association between 241 SNPs in 6 select vitamin D metabolic genes in relation to longitudinal change in FEV1 in Offspring participants and pursued replication of these findings in a meta-analyzed set of 4 independent cohorts.Results
We found a positive cross-sectional association between 25(OH)D and FEV1 in FHS Offspring and Third Generation participants (P = 0.004). There was little or no association between 25(OH)D and longitudinal change in FEV1 in Third Generation participants (P = 0.97). In Offspring participants, the CYP2R1 gene, hypothesized to influence usual serum 25(OH)D status, was associated with longitudinal change in FEV1 (gene-based P < 0.05). The most significantly associated SNP from CYP2R1 had a consistent direction of association with FEV1 in the meta-analyzed set of replication cohorts, but the association did not reach statistical significance thresholds (P = 0.09).Conclusions
Serum 25(OH)D status was associated with cross-sectional FEV1, but not longitudinal change in FEV1. The inconsistent associations may be driven by differences in the groups studied. CYP2R1 demonstrated a gene-based association with longitudinal change in FEV1 and is a promising candidate gene for further studies.Electronic supplementary material
The online version of this article (doi:10.1186/s12931-015-0238-y) contains supplementary material, which is available to authorized users. 相似文献7.
The mitochondrial tRNAs of Trypanosoma brucei are nuclear encoded 总被引:17,自引:0,他引:17
The mitochondrial DNA of Trypanosoma brucei is organized as a catenated network of maxicircles and minicircles. The maxicircles are equivalent to the typical mitochondrial genome except that the genes for the mitochondrial tRNAs have not been identified by sequence analysis of the maxicircle DNA. The apparent absence of tRNA genes in the maxicircle DNA suggests that the mitochondrial tRNAs are encoded by either the minicircle or the nuclear DNA. In order to determine their genomic origin, we isolated and identified the mitochondrial tRNAs of T. brucei. We show that these mitochondrial tRNAs are truly mitochondrially located in vivo and that they are free from detectable contamination by cytosolic RNAs. By hybridization analysis, using mitochondrial tRNAs as the probe, we determined that the mitochondrial tRNAs are encoded by nuclear DNA. This implies that RNAs, like proteins, are imported into the mitochondria. We investigated the relationship between the cytosolic and the mitochondrial tRNA genes and show that there are unique cytosolic tRNA genes, unique mitochondrial tRNA genes, and tRNA genes which appear to be shared and whose products are therefore targeted to both the cytosol and the mitochondrion. 相似文献
8.
9.
Out of Africa and back again: nested cladistic analysis of human Y chromosome variation 总被引:18,自引:3,他引:15
Hammer MF; Karafet T; Rasanayagam A; Wood ET; Altheide TK; Jenkins T; Griffiths RC; Templeton AR; Zegura SL 《Molecular biology and evolution》1998,15(4):427-441
We surveyed nine diallelic polymorphic sites on the Y chromosomes of 1,544
individuals from Africa, Asia, Europe, Oceania, and the New World.
Phylogenetic analyses of these nine sites resulted in a tree for 10
distinct Y haplotypes with a coalescence time of approximately 150,000
years. The 10 haplotypes were unevenly distributed among human populations:
5 were restricted to a particular continent, 2 were shared between Africa
and Europe, 1 was present only in the Old World, and 2 were found in all
geographic regions surveyed. The ancestral haplotype was limited to African
populations. Random permutation procedures revealed statistically
significant patterns of geographical structuring of this paternal genetic
variation. The results of a nested cladistic analysis indicated that these
geographical associations arose through a combination of processes,
including restricted, recurrent gene flow (isolation by distance) and range
expansions. We inferred that one of the oldest events in the nested
cladistic analysis was a range expansion out of Africa which resulted in
the complete replacement of Y chromosomes throughout the Old World, a
finding consistent with many versions of the Out of Africa Replacement
Model. A second and more recent range expansion brought Asian Y chromosomes
back to Africa without replacing the indigenous African male gene pool.
Thus, the previously observed high levels of Y chromosomal genetic
diversity in Africa may be due in part to bidirectional population
movements. Finally, a comparison of our results with those from nested
cladistic analyses of human mtDNA and beta-globin data revealed different
patterns of inferences for males and females concerning the relative roles
of population history (range expansions) and population structure
(recurrent gene flow), thereby adding a new sex-specific component to
models of human evolution.
相似文献
10.
Interaction of cross-sectional area, driving pressure, and airflow of passive velopharynx 总被引:2,自引:0,他引:2
Isono Shiroh; Feroah Thom R.; Hajduk Eric A.; Brant Rollin; Whitelaw William A.; Remmers John E. 《Journal of applied physiology》1997,83(3):851-859
Isono, Shiroh, Thom R. Feroah, Eric A. Hajduk, Rollin Brant,William A. Whitelaw, and John E. Remmers. Interaction ofcross-sectional area, driving pressure, and airflow of passive velopharynx. J. Appl. Physiol. 83(3):851-859, 1997.Previous studies have shown that, when thepharyngeal muscles are relaxed, the velopharynx is a highly compliantsegment of the pharynx. Thus, under these circumstances,cross-sectional area of the velopharynx (AVP), drivingpressure across the velopharynx (P), and inspiratory airflow(I) willbe mutually interdependent variables. The purpose of the presentinvestigation was to describe the interrelation among these threevariables during inspiration. We studied 15 sleeping patients withobstructive sleep apnea/hypopnea when the pharyngeal muscles wererendered hypotonic by applying continuous positive airway pressure tothe nasal airway.AVP, determined by endoscopic imaging, was significantly greater at onset ofI limitationthan at minimum oropharyngeal pressure(P < 0.01). Snoring was neverobserved duringIlimitation. In a subgroup of six patients, values for P,I, andAVP were obtainedat 0.1-s intervals at various levels of mask pressure. For these sixpatients, the mathematical expressionI = 0.657(AVP/Amax) · P0.332,where Amax ismaximal AVP,described the relationship among the three variables(R2 = 0.962) forflow-limited and non-flow-limited inspirations. The impedance of thepassive velopharynx, defined asP0.33/,was inversely related toAVP and increaseddramatically when AVP was <0.3cm2. In summary, we observed aprogressive decrease inAVP during flow-limited inspiration in patients with obstructive sleep apnea. Thisconstriction of the velopharynx contributes to an increase invelopharyngeal impedance that, in turn, counterbalances the increase inP during flow limitation. 相似文献