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51.
Effect of prone positioning on the survival of patients with acute respiratory failure 总被引:40,自引:0,他引:40
Gattinoni L Tognoni G Pesenti A Taccone P Mascheroni D Labarta V Malacrida R Di Giulio P Fumagalli R Pelosi P Brazzi L Latini R;Prone-Supine Study Group 《The New England journal of medicine》2001,345(8):568-573
BACKGROUND: Although placing patients with acute respiratory failure in a prone (face down) position improves their oxygenation 60 to 70 percent of the time, the effect on survival is not known. METHODS: In a multicenter, randomized trial, we compared conventional treatment (in the supine position) of patients with acute lung injury or the acute respiratory distress syndrome with a predefined strategy of placing patients in a prone position for six or more hours daily for 10 days. We enrolled 304 patients, 152 in each group. RESULTS: The mortality rate was 23.0 percent during the 10-day study period, 49.3 percent at the time of discharge from the intensive care unit, and 60.5 percent at 6 months. The relative risk of death in the prone group as compared with the supine group was 0.84 at the end of the study period (95 percent confidence interval, 0.56 to 1.27), 1.05 at the time of discharge from the intensive care unit (95 percent confidence interval, 0.84 to 1.32), and 1.06 at six months (95 percent confidence interval, 0.88 to 1.28). During the study period the mean (+/-SD) increase in the ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen, measured each morning while patients were supine, was greater in the prone than the supine group (63.0+/-66.8 vs. 44.6+/-68.2, P=0.02). The incidence of complications related to positioning (such as pressure sores and accidental extubation) was similar in the two groups. CONCLUSIONS: Although placing patients with acute respiratory failure in a prone position improves their oxygenation, it does not improve survival. 相似文献
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53.
Genes encoding the common gonadotrophin subunit and folliclestimulating hormone (FSH)-specific ß subunit wereisolated from a DNA library derived from human fetal liver cells,and inserted into separate expression vectors containing a selectable/amplifiablegene. These vectors were inserted into the genome of the Chinesehamster ovary cell line, resulting in expression of large amountsof biologically active human (h)FSH. This cell line was culturedon microcarrier beads in a large-scale bioreactor. hFSH in thecell culture supernatant was purified to homogeneity by a multistepprocess. The mature ß subunit had seven fewer aminoacid residues than reported in the literature and three otherdifferences were found in the sequence. Similar oligosaccharidestructures were present on recombinant (r)-hFSH and a purifiedurinary (u)-hFSH preparation. In-vitro and in-vivo, the biologicalactivities of u- and r-hFSH were indistinguishable, r-hFSH wasformulated in ampoules containing 75 IU FSH activity ( 7.5 µgFSH), which accounts for >99% of the protein content of thepreparation. Studies in non-human primates and human volunteersshowed the pharmacokinetics of u- and r-hFSH to be similar.In healthy volunteers, r-hFSH stimulated follicular developmentand induced significant increases in serum oestradiol and inhibin.Clinical experience with r-hFSH has shown it is more effectiveat stimulating ovarian follicle growth than urinary gonadotrophins.It is also effective at initiating spermatogenesis when giventogether with human chorionic gonadotrophin. 相似文献
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55.
BACKGROUND: The clinical efficacy and safety of a six-grass pollen allergoid has been studied. The advent of more exacting clinical guidelines and a better appreciation of the possible mechanisms of treatment prompted this reappraisal. METHODS: A 2-year double-blind multicentre placebo-controlled phase 3 clinical trial was undertaken in 154 patients suffering symptoms of rhinoconjunctivitis with or without asthma (GINA I or II). Therapy comprised two consecutive preseasonal short-courses of subcutaneous injections using a grass pollen allergoid adsorbed to aluminium hydroxide. RESULTS: A combined symptom and medication score (SMS) was used as the primary end-point for clinical efficacy. SMS from the first year showed a significant difference of 26.6% between the two study groups (P=0.026) and this was improved after the second year when there was a 48.4% difference in SMS between active and placebo treatment in favour of the allergoid (P = 0.018). Highly significant increases in grass pollen allergen-specific IgG1 and IgG4 antibody concentrations were measured in association with active treatment. Allergen tolerance was increased as judged by a conjunctival provocation test and significant improvements in quality of life were documented using a standardized questionnaire. The allergoid was well tolerated. CONCLUSIONS: The grass pollen allergoid was shown to be safe and clinically efficacious in the management of hay fever with or without asthma (GINA I or II). 相似文献
56.
Kristiansen OP Karlsen AE Larsen ZM Johannesen J Pociot F Mandrup-Poulsen T;Danish IDDM Epidemiology Genetics Group Danish Study Group of IDDM in Childhood 《Scandinavian journal of immunology》2004,59(6):582-591
CD4 is a candidate gene in autoimmune diseases, including Type 1 diabetes mellitus (T1DM), because the CD4 receptor is crucial for appropriate antigen responses of CD4(+) T cells. We previously found linkage between a CD4-1188(TTTTC)(5-14) promoter polymorphism and T1DM. In the present study, we screened the human CD4 promoter for mutations and identified three frequent single nucleotide polymorphisms (SNPs): CD4-181C/G, CD4-521C/G and CD4-1050T/C. The SNPs are in strong linkage disequilibrium (LD) and association with the CD4-1188(TTTTC)(5-14) alleles, and we observed nine CD4 promoter haplotypes, of which four are frequent. We genotyped the SNPs in 253 Danish T1DM families (1129 individuals) and found evidence for linkage and association of a CD4 (A4(-1188)T(-1050)G(-521)C(-181)) haplotype to T1DM. In reporter studies, we show that (1) the T1DM-associated CD4 haplotype encodes high constitutive promoter activity and (2) the CD4-181G variant encodes higher stimulated promoter activity than the CD4-181C variant. This difference is in part neutralized in the frequently occurring CD4 promoter haplotypes by the more upstream genetic variants. Thus, we report functional impact of a novel CD4-181C/G SNP on stimulated CD4 promoter activity and the identification of a novel CD4 haplotype with high constitutive promoter activity that is linked and associated with T1DM. 相似文献
57.
Amir?R?RazaviEmail author Hans?Gill Olle?St?l Marie?Sundquist Sten?Thorstenson Hans??hlfeldt Nosrat?Shahsavar the South-East Swedish Breast Cancer Study Group 《BMC medical informatics and decision making》2005,5(1):29
Background
A common approach in exploring register data is to find relationships between outcomes and predictors by using multiple regression analysis (MRA). If there is more than one outcome variable, the analysis must then be repeated, and the results combined in some arbitrary fashion. In contrast, Canonical Correlation Analysis (CCA) has the ability to analyze multiple outcomes at the same time. 相似文献58.
59.
Oral Anticoagulation Monitoring Study Group 《American journal of clinical pathology》2001,115(2):288-296
We enrolled 386 subjects in a multicenter study of a point-of-care (POC) prothrombin time (PT) testing device. POC tests were performed by health care professionals using venous and finger-stick specimens and by patients using finger-stick specimens. Venous blood also was analyzed in the local hospital laboratory and a national reference laboratory. Accurate POC results were obtained by professionals using both types of specimens. Patients' results were equivalent to those of professionals. The identification of the patient's therapeutic status based on the International Normalized Ratio (INR) was equivalent for POC and local hospital laboratory PT results; 75% of local laboratory results and 77% of POC results were within 0.4 INR of reference laboratory results, while 93% of either system (POC or local laboratory) were within 0.7 INR. Patients overwhelmingly reported satisfaction with the self-test, including the finger stick and device operation. The INR from the POC device is clinically equivalent to the laboratory INR for assessment of anticoagulation status and management decisions in professional and self-testing environments. Patients can learn to perform accurate PT testing, and POC PT testing is feasible in patients' homes. 相似文献
60.
Elkins MK Vittinghoff E Baranzini SE Hecht FM Sriram U Busch MP Levy JA Oksenberg JR;San Francisco Primary Infection Group 《Genes and immunity》2005,6(1):66-69
In chronically HIV infected individuals, a number of functional B cell abnormalities have been described. However, the immediate changes that occur in the B cell compartment following viral exposure and how they affect the long-term course of infection are not well understood. We report the longitudinal analysis of B cell repertoires during early infection in untreated and treated individuals receiving highly active antiretroviral therapy (HAART). Analysis was based on IgG heavy chain gene utilization and CDR3 length measurement and relationship with CD4/CD8 counts, viral load, and total serum IgG, and anti-HIV antibodies levels. Repertoires were assessed at baseline and at weeks 2, 4, 12, 24, and 72 after initiation of therapy. The findings indicate a stable peripheral B cell repertoire during the first 72 weeks following infection, particularly in the HAART treated patients. A modest association between B cell repertoire integrity and viremia levels as well as treatment was detected. 相似文献