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101.
Edward Perkins Carter 《The Journal of experimental medicine》1914,20(1):81-91
The determination of the percentage of CO2 in the alveolar air, by the method of Haldane and Priestley, is sufficiently accurate for clinical purposes when the individual is at rest. It is evident, however, that an error may arise in the determination of the percentage of CO2 in the alveolar air, due to the time during the forced expiration, short of the extreme limit, at which the sample may be unconsciously taken. This error can only be overcome by taking several samples. In individuals at rest having a tidal air below 425 cubic centimeters, the method of Douglas and Haldane for the calculation of the dead space gives approximately accurate results; with a tidal air above 425 cubic centimeters the results obtained may be wholly inaccurate. In patients with marked pulmonary tuberculosis so slight an effort as that involved in collecting the expired air tends to lower the percentage of CO2 in the alveolar air. In collecting the expired air by the rubber bag method, it is absolutely essential that the bag be washed out with ordinary atmospheric air after every observation. 相似文献
102.
Community coalitions are a recognized strategy for addressing pressing public health problems. Despite the promise of coalitions as an effective prevention strategy, results linking coalition efforts to positive community outcomes are mixed. To date, research has primarily focused on determining organizational attributes related to successful internal coalition functioning. The authors' research complements and adds to this literature by offering a network conceptualization of coalition formation in which coalition participation is studied within the broader context of local organizational networks both within and beyond a coalition. The authors examine participation in the first year of a youth violence prevention coalition exploring both differences between participating and nonparticipating organizations and levels of participation. Each network variable, reflecting prior collaboration and being viewed by other organizations as a local leader, approximately doubled the explained variance in coalition participation beyond the predictive power of all available organizational attributes combined. Results suggest that initial coalition participation emerged out of a preexisting network of interorganizational relations and provide an alternative perspective on coalition formation that goes beyond conceptual orientations that treat coalitions as bounded organizational entities that exist apart from the communities in which they are embedded. 相似文献
103.
Prevalence and Contributors to Low‐grade Inflammation in Three U.S. Populations of Reproductive Age Women 下载免费PDF全文
104.
105.
106.
Human monoclonal antibodies neutralizing varicella-zoster virus 总被引:3,自引:0,他引:3
S K Foung S Perkins C Koropchak D M Fishwild A E Wittek E G Engleman F C Grumet A M Arvin 《The Journal of infectious diseases》1985,152(2):280-285
Hybridomas secreting human monoclonal antibodies to varicella-zoster virus were produced by fusing B cells of a patient recovering from acute varicella infection with a human-mouse cell line. Two hybrid lines have continued to secrete IgG1, one with kappa and the other with lambda chains, for at least 12 months. Each antibody neutralizes virus infectivity between 1-5 micrograms of partially purified immunoglobulin/ml, each shows a different pattern of immunofluorescent staining of virus-infected cells, and one identifies three viral proteins with molecular weights of 60,000, 95,000, and 97,000. 相似文献
107.
Saskia PJ Verkleij Pim AJ Luijsterburg Sten P Willemsen Bart W Koes Arthur M Bohnen Sita MA Bierma-Zeinstra 《The British journal of general practice》2015,65(637):e530-e537
Background
The effectiveness of diclofenac versus paracetamol in primary care patients with pain caused by knee osteoarthritis is unclear.Aim
To assess the effectiveness of diclofenac compared with paracetamol over a period of 2, 4, and 12 weeks in patients with knee osteoarthritis.Design and setting
Randomised controlled trial in general practice.Method
There were 104 patients included in the study, they were aged ≥45 years consulting their GP with knee pain caused by knee osteoarthritis. Patients were randomly allocated to diclofenac (n = 52) or paracetamol (n = 52) for at least 2 weeks. Primary outcomes were daily knee pain severity, and knee pain and function measured with the Knee Injury and Osteoarthritis Outcome Score (KOOS).Results
Over a period of 2- and 4-weeks follow-up, no significant difference in daily knee pain was found between the patient groups: estimated differences of 0.5 (95% CI = −0.2 to 1.3) and −0.2 (95% CI = −1.0 to 0.7), respectively. Over the 12-weeks follow-up, no significant differences were found between both groups for KOOS pain: estimated difference of −2.8 (95% CI = −10.7 to 5.1) and KOOS function of −2.7 (−10.6 to 5.0).Conclusion
Over a period of 2- and 4-weeks follow-up no significant difference in daily measured knee pain severity was found between primary care patients with knee osteoarthritis taking paracetamol or diclofenac. Also, over a period of 12-weeks follow-up no significant differences were found regarding KOOS pain and KOOS function between both groups. Patients more frequently reported minor adverse events after taking diclofenac (64%) than paracetamol (46%). 相似文献108.
Perkins SL Pickering D Lowe EJ Zwick D Abromowitch M Davenport G Cairo MS Sanger WG 《British journal of haematology》2005,131(5):624-627
Anaplastic large cell lymphoma (ALCL) comprises 10-15% of childhood non-Hodgkin lymphomas (NHL). Systemic ALCL is highly associated with anaplastic lymphoma kinase (ALK) gene translocations with over-expression of ALK protein. We studied ALK rearrangements using fluorescence in situ hybridisation (FISH) and ALK immunohistochemical staining in 43 paediatric systemic ALCLs. FISH (performed on 35 cases) identified a translocation in 29 cases (83%). Immunohistochemistry identified ALK over-expression in 42/43 cases (97%) with the single ALK-negative case demonstrating an ALK rearrangement by FISH, indicating 100% incidence of ALK translocations. 相似文献
109.
Styles LA; Schalkwijk CG; Aarsman AJ; Vichinsky EP; Lubin BH; Kuypers FA 《Blood》1996,87(6):2573-2578
Acute chest syndrome (ACS) is associated with significant morbidity and is the leading cause of death in patients with sickle cell disease (SCD). Recent reports suggest that bone marrow fat embolism can be detected in many cases of severe ACS. Secretory phospholipase A2 (sPLA2) is an important inflammatory mediator and liberates free fatty acids, which are felt to be responsible for the acute lung injury of the fat embolism syndrome. We measured SPLA2 levels in 35 SCD patients during 20 admissions for ACS, 10 admissions for vaso-occlusive crisis, and during 12 clinic visits when patients were at the steady state. Eleven non-SCD patients with pneumonia were also evaluated. To determine if there was a relationship between sPLA2 and the severity of ACS we correlated SPLA2 levels with the clinical course of the patient. In comparison with normal controls (mean = 3.1 +/- 1.1 ng/mL), the non- SCD patients with pneumonia (mean = 68.6 +/- 82.9 ng/mL) and all three SCD patient groups had an elevation of SPLA2 (steady state mean = 10.0 +/- 8.4 ng/mL; vaso-occlusive crisis mean = 23.7 +/- 40.5 ng/mL; ACS mean = 336 +/- 209 ng/mL). In patients with ACS sPLA2 levels were 100- fold greater than normal control values, 35 times greater than values in SCD patients at baseline, and five times greater than non-SCD patients with pneumonia. The degree of SPLA2 elevation in ACS correlated with three different measures of clinical severity and, in patients followed sequentially, the rise in SPLA2 coincided with the onset of ACS. The dramatic elevation of SPLA2 in patients with ACS but not in patients with vaso-occlusive crisis or non-SCD patients with pneumonia and the correlation between levels of SPLA2 and clinical severity suggest a role for SPLA2 in the diagnosis and, perhaps, in the pathophysiology of patients with ACS. 相似文献
110.
Mice lacking the erythroid Kruppel-like factor (EKLF) die in utero at embryonic day 15 (E15) from severe anemia. EKLF(-/-) embryos display a marked deficit in beta-globin gene expression. To test whether beta-globin deficiency was solely responsible for the anemia and intrauterine death, we corrected the globin chain imbalance in EKLF(-/-) embryos by breeding with a strain of mice that express high levels of human gamma-globin. Despite efficient production of hybrid malpha(2)-hgamma(2) hemoglobin in the fetal livers of EKLF(-/-) animals, hemolysis was not corrected and survival was not prolonged. We concluded that deficiency of nonglobin EKLF target genes is a major contributor to the definitive red blood cell abnormalities and prenatal death in EKLF(-/-) embryos. These results suggest that strategies designed to antagonize EKLF function in adults with hemoglobinopathy, in an attempt to reactivate gamma-globin gene expression, may adversely affect other essential aspects of red blood cell physiology. (Blood. 2000;95:1827-1833) 相似文献