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921.
Yewande E. Odeyemi ODene Lewis Julius Ngwa Kristen Dodd Richard F. Gillum Alem Mehari 《Journal of the National Medical Association》2019,111(1):94-100
Purpose
There is presently an ongoing debate on the relative merits of suggested criteria for spirometric airway obstruction. This study tests the null hypothesis that no superiority exists with the use of fixed ratio (FR) of forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) < 0.7 versus less than lower limit predicted (LLN) criteria with or without FEV1 <80% predicted in regards to future mortality.Methods
In 1988–1994 the Third National Health and Nutrition Examination Survey (NHANES III) measured FEV1 and FVC with mortality follow-up data through December 31, 2011. For this survival analysis 7472 persons aged 40 and over with complete data formed the analytic sample.Results
There were a total of 3554 deaths. Weighted Cox proportional hazards regression revealed an increased hazard ratio in persons with both fixed ratio and lower limit of normal with a low FEV1 (1.79, p < 0.0001), in those with fixed ratio only with a low FEV1 (1.77, p < 0.0001), in those with abnormal fixed ratio only with a normal FEV1 (1.28, p < 0.0001) compared with persons with no airflow obstruction (reference group). These remained significant after adjusting for demographic variables and other confounding variables.Conclusions
The addition of FEV1 < 80% of predicted increased the prognostic power of the fixed ratio <0.7 and/or below the lower limit of predicted criteria for airway obstruction. 相似文献922.
923.
Max J. Kurz Konstantinos Pothakos Sakeena Jamaluddin Melissa Scott-Pandorf Chris Arellano Yuen-Sum Lau 《Neuroscience letters》2007
The purpose of this investigation was to determine if a chronic Parkinson's disease mouse model will display less certainty in its gait pattern due to basal ganglia dysfunction. A chronic Parkinson's disease mouse model was induced by injecting male C57/BL mice with 10 doses of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (25 mg/kg) (MPTP) and probenecid (250 mg/kg) (P) over 5 weeks. This chronic model produces a severe and persistent loss of nigrostriatal neurons resulting in dopamine depletion and locomotor impairment. The control mice were treated with probenecid alone. Fifteen weeks after the last MPTP/P treatment, the mice were videotaped in the sagittal plane with a digital camera (60 Hz) as they ran on a motorized treadmill at a speed of 10 m/min. The indices of gait and gait variability were calculated. Stride length was significantly (p = 0.016) more variable in the chronic MPTP/P mice. Additionally, the chronic MPTP/P mice had a statistically less certain gait pattern when compared to the control mice (p = 0.02). These results suggest that variability in the gait pattern can be used to evaluate changes in neural function. Additionally, our results imply that disorder of the basal ganglia results in less certainty in modulating the descending motor command that controls the gait pattern. 相似文献
924.
Giorgio Torelli Eloisa Milla Leonard I. Kleinman Alide Faelli 《Pflügers Archiv : European journal of physiology》1973,342(3):219-230
Summary The relationship between sodium reabsorption and oxygen consumption was studied in an isolated rabbit kidney preparation perfused with blood at 37, 28 and 19° C. When the temperature was lowered from 37° C to 28° C and to 19°C the rate of oxygen consumption and of the maximal P.A.H. excretion (Tm P.A.H.) decreased more than that of sodium reabsorption.TheQ
10 for sodium reabsorption is about 1.8, while that for maximal P.A.H. excretion is 2.5. Some hypothesis on the possible mechanisms of the lowQ
10 of the Na+ reabsorption are forwarded.Preliminary reports have been published [Boll. Soc. Ital. Biol. Sper.43, 1019–1023 (1966) and44, 1784–1787 (1967);45, 860–862 (1969) and45, 863–865 (1969)]. 相似文献
925.
Fiji disease fijivirus (FDV) genomic segments 1 (S1) and 3 (S3) were completely sequenced. FDV S1 comprised 4532nt and was predicted to encode a 170.6kDa protein. FDV S3 comprised 3623nt and was predicted to encode a 135.5kDa protein. The terminal sequences of S1 and S3 were 5 AAGUUUUU......CAGCUAGCGUC 3 and 5 AAGUUUUU......CAGCAGAUGUC 3, respectively, and located immediately adjacent to these sequences were 12bp imperfect inverted repeats. The predicted translation product of FDV S1 showed highest similarity to Rice black-streaked dwarf virus (RBSDV) S1 and is thought to encode the viral RNA-dependent RNA polymerase (RdRp). The predicted translation product of FDV S3 was found to be most similar to RBSDV S4 which is thought to encode the 'B-spike' protein. The FDV sequence contained an ATP/GTP binding motif and a leucine zipper motif, but these motifs were not found in the RBSDV sequence. Phylogenetic analysis based on the amino acid sequences of the RdRp of FDV S1 and other reoviruses revealed that the fijiviruses form a cluster close to the oryzaviruses. The RdRp sequences were grouped into genera that were consistent with the current reovirus classification scheme that is based on physico-chemical and biological properties. 相似文献
926.
Adoptive transfer of CD4+ T cells into scid mice leads to a chronic colitis in the recipients. The transferred CD4+ T cells accumulate in the intestinal lamina propria (LP), express an activated Th1 phenotype and proliferate vigorously when exposed ex vivo to enteric bacterial antigens. As LP CD4+ T cells from normal BALB/c mice do not respond to enteric bacterial antigens, we have investigated whether colonic LP-derived CD4+ T cells from normal mice suppress the antibacterial response of CD4+ T cells from scid mice with colitis. LP-derived CD4+ T cells cocultured with bone marrow-derived dendritic cells effectively suppress the antibacterial proliferative response of CD4+ T cells from scid mice with colitis. The majority of these LP T-reg cells display a nonactivated phenotype and suppression is independent of antigen exposure, is partly mediated by soluble factor(s) different from IL-10 and TGF-beta, and is not prevented by the addition of high doses of IL-2 to the assay culture. Functionally and phenotypically the T-reg cells of the present study differ from previously described subsets of T-reg cells. The presence of T cells with a regulatory potential in the normal colonic mucosa suggests a role for these cells in the maintenance of local immune homeostasis of the gut. 相似文献
927.
Infants with Ureaplasma urealyticum in the lower respiratory tract are at risk for chronic lung disease (CLD) or bronchopulmonary dysplasia (BPD) but causality has been difficult to prove. The goal of this study was to identify ureaplasma in human neonatal lung tissue using the in situ hybridization (ISH) procedure described in Part 1 (Exp. Mol. Pathol., in press) of this report. By correlating their presence with the histopathologic findings, it may be possible to provide further evidence of the pathogenicity of ureaplasmas and their association with BPD. Lung autopsy tissue from seven infants with positive cultures and seven infants with negative cultures for ureaplasma were included in the study. All culture-positive infants were positive for ureaplasma on ISH and all had histopathologic evidence of BPD. Two of the seven infants with negative cultures were positive for ureaplasma with ISH. Of interest, these two infants were also found to have BPD at autopsy. The other five infants with negative cultures were also negative for ureaplasma on ISH and had no evidence of BPD. This study correlates the presence of U. urealyticum by ISH with the finding of BPD on histopathologic evaluation and provides evidence that it has a role in the development of CLD. 相似文献
928.
P. M. T. Deen Søren Nielsen René J. M. Bindels Carel H. van Os 《Pflügers Archiv : European journal of physiology》1997,433(6):780-787
Aquaporin-1 is present in the apical and basolateral membranes in proximal tubules and descending limbs of Henlé’s loop.
In order to be able to study the routing of Aquaporin-1 and the regulation of Aquaporin-1-mediated transcellular water flow,
we stably transfected LLC-PK1 and MDCK-HRS cell lines with an Aquaporin-1 expression construct. LLC-PK1 clone 7 and MDCK clone K integrated two and one copies, respectively, which was reflected in the amount of Aquaporin-1 mRNA expressed in both clones. The Aquaporin-1 protein levels, however, were similar. In both clones, immuno-electronmicroscopy
showed extensive labelling of Aquaporin-1 on the basolateral plasma membrane, endosomal vesicles and the apical plasma membrane,
including the microvilli. To measure transcellular water permeation, a simple method was applied using phenol-red as a cell-impermeant
marker of concentration. In contrast to the native cell lines, both clones revealed a high transcellular osmotic water permeability,
which could not be influenced by forskolin add/3-isobutyl-1-methylxanthine (IBMX) or the phorbol ester 12-O-tetradecanoyl 13-acetate (TPA). After glutaraldehyde fixation, it was inhibitable by HgCl2. These results indicate that targeting of Aquaporin-1 to the apical and basolateral plasma membrane is independent of cell
type and show for the first time that water flow through a cultured epithelium can be blocked by mercurial compounds.
Received: 9 October 1996 / Received after revision: 3 January 1997 / Accepted: 8 January 1997 相似文献
929.
930.
AIMS: The objective of this study was to assess apoptotic activity in gestational trophoblastic disease (GTD) and its prognostic value in hydatidiform mole (HM). METHODS AND RESULTS: Expression of the specific caspase cleavage site within cytokeratin 18 was assessed immunohistochemically using the monoclonal antibody M30 CytoDeath in 12 spontaneous abortions, 22 partial and 57 complete HM, eight choriocarcinoma (CCA) and 28 normal placentas. The M30 immunoreactivity occurred predominantly in the syncytiotrophoblasts. A significantly higher M30 index in HM and CCA was found when compared with normal placentas and spontaneous abortions (P < 0.001). The M30 index of those HM which spontaneously regressed was significantly higher than those HM which developed persistent disease requiring chemotherapy (P < 0.001). The M30 index correlated with another apoptotic index previously detected by TdT-mediated dUTP nick-end labelling (TUNEL) (P = 0.007) and the proliferation index assessed by the Ki67 antigen (P = 0.034). CONCLUSIONS: We conclude that apoptosis is important in the pathogenesis of GTD. Assessment of apoptotic activity in HM by the M30 index may be considered as an alternative prognostic indicator for predicting the clinical behaviour. 相似文献