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51.
P Mols  C H Huynh  P Dechamps  N Naeije  M Guillaume  H Ham 《Chest》1989,96(6):1280-1284
Pulmonary arterial hypertension represents an important parameter for the assessment of the severity of chronic bronchitis. The measurement of the pulmonary arterial pressure, however, requires invasive techniques of limited routine use because of costs and associated risks. The aim of this study is to evaluate whether the 81mKr right ventricular ejection fraction and parameters derived from equilibrium 99mTc red blood cells' right ventricular curve allow a better estimation of PAP than the 99mTc RVEF. In 41 patients with severe chronic bronchitis, the linear correlation between PAP and 99mTc RVEF was -0.61 (p less than 0.001). None of the parameters derived from the right ventricular curve was better correlated to PAP than the 99mTc RVEF. In 16 other chronic bronchitis patients, the 81mKr RVEF correlated moderately to PAP. In conclusion, the alternative isotopic methods proposed in this work do not provide a reliable estimation of pulmonary arterial pressure in patients with chronic bronchitis.  相似文献   
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53.
Hemodynamics, blood gases, lung mechanics, and the distributions of ventilation-perfusion ratios (VA/Q) were studied before and after iv diltiazem, 0.5 mg/kg over 30 min, in 6 patients with pulmonary hypertension secondary to the adult respiratory distress syndrome (ARDS) ventilated with 7 to 20 cm H2O positive end-expiratory pressure (PEEP). Diltiazem decreased systemic and pulmonary arterial pressures without changes in cardiac output and in filling pressures of the heart, and with a slowing of heart rate. Pulmonary vascular resistances decreased from 401 +/- 59 to 329 +/- 58 dyne.s.cm-5.m2 (mean +/- SEM), p less than 0.01. Arterial Po2 decreased from 87 +/- 10 to 80 +/- 11 mm Hg (p less than 0.02) without changes in arterial PCO2, mixed venous PO2, and O2 consumption. Lung compliance and airway resistances did not change. Diltiazem increased true shunt from 23 +/- 5 to 30 +/- 7% of total blood flow (p less than 0.02) without other modification in the pattern of VA/Q distribution as measured by the multiple inert gas elimination technique. These results suggest that pulmonary vascular tone contributes to the maintenance of VA/Q matching in patients with ARDS.  相似文献   
54.

Introduction

We investigated the impact of Cardio-Pulmonary Resuscitation (CPR) instruction by children on the attitude of people to perform bystander CPR.

Methods

In 2012, children from primary and secondary school (age span 11–13 years) received a free individual CPR training package containing an inexpensive manikin and a training video. After a CPR training session by their class teacher, they were invited to teach their relatives and friends. After the training, the trainees of the children were invited to participate in a web survey, containing a test and questions about prior CPR training and about their attitude towards bystander CPR (BCPR) before and after the training. We measured the impact on the attitude to perform BCPR and the theoretical knowledge transfer by the children.

Results

A total of 4012 training packages were distributed to 72 schools of which 55 class teachers subscribed their students (n = 822) for the training programme for relatives and friends. After a validation procedure, 874 trainees of 290 children were included in the study. In comparison to trainees of secondary schoolchildren, trainees of primary schoolchildren scored better for the test as well as for a positive change of attitude towards future BCPR (P < 0.001). For every child-instructor 1.7 people changed their attitude towards BCPR positively.

Conclusions

Instructing schoolchildren to teach their relatives and friends in Basic Life Support (BLS) led to a more positive attitude towards BCPR. The results were more positive with trainees from primary schoolchildren than with trainees from secondary schoolchildren.  相似文献   
55.
56.

Background

The objective of this study was to systematically review all available literature concerning chemotherapy-induced peripheral neuropathy (CIPN) and quality of life (QOL) among cancer patients.

Methods

A computerized search of the literature was performed in December 2013. Articles were included if they investigated CIPN and QOL among cancer patients. Twenty-five articles were selected and were subjected to a 13-item quality checklist independently by two investigators.

Results

The methodological quality of the majority of the selected studies was adequate to high. The included studies differed tremendously with respect to study design (19 prospective studies, 5 cross-sectional, 1 both cross-sectional and prospective), patient population (lung, colorectal, ovarian, endometrial, cervical or breast cancer, lymphoma, acute lymphoblastic leukemia, or a mixed population), number of included patients (ranging from 14 to 1643), and ways to assess CIPN (objectively, subjectively, or both). Of the 25 included studies, 11 assessed the association of CIPN on patients’ QOL. While three of these studies did not find an association between CIPN and QOL, the others concluded that more CIPN was associated with a lower QOL.

Implications for cancer survivors

Although the included studies in this systematic review were very diverse, which impedes drawing firm conclusions on this topic, CIPN is likely to have a negative association with QOL. The variety of the studied patient populations and chemotherapeutic agents in the existing studies calls for further studies on this topic. These studies are preferably prospective in nature, include a large number of patients, and assess QOL and CIPN with validated questionnaires.  相似文献   
57.
58.
The course of fatigue and quality of life in survivors of non-Hodgkin’s lymphoma is unknown. The aims of this study were, therefore, to assess fatigue and quality of life in patients with non-Hodgkin’s lymphoma following primary treatment, compare fatigue and quality of life in these patients with those of an age- and sex matched normative population to assess the severity of concerns and identify associations with fatigue of survivors who remained fatigued. The population-based Eindhoven Cancer Registry was used to select all patients diagnosed with non-Hodgkin’s lymphoma from 1999–2009. The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire and the Fatigue Assessment Scale were completed once by 824 survivors of non-Hodgkin’s lymphoma (80% response rate); 434 survivors completed these questionnaires again 1 year later. Survivors of non-Hodgkin’s lymphoma reported more clinically relevant fatigue up till 10 years post-diagnosis compared to a normative population (P<0.001). Mean fatigue scores remained fairly stable over time (T1: x¯=28, SD=26; T2:=30, SD=27, P=0.14): 22–28% of survivors reported deterioration, 19–23% reported improvement and 44–54% reported constant fatigue. Survivors who reported constant fatigue were more often diagnosed with stage IV disease and had more comorbid diseases. They were additionally more often female and divorced. Having comorbidities and being without a partner were also associated with constant fatigue in the normative population. In conclusion, six out of every ten responding non-Hodgkin’s lymphoma survivors reported a high level of fatigue up till 10 years after diagnosis. Mean fatigue scores remained stable over time and survivors reporting constant fatigue more often had stage IV disease at diagnosis and comorbidities.  相似文献   
59.
Future energy systems must call upon clean and renewable sources capable of reducing associated CO2 emissions. The present research opens new perspectives for renewable energy-based hydrogen production by water splitting using metal oxide oxidation/reduction reactants. An earlier multicriteria assessment defined top priorities, with MnFe2O4/Na2CO3/H2O and Mn3O4/MnO/NaMnO2/H2O multistep redox cycles having the highest potential. The latter redox system was previously assessed and proven difficult to be conducted. The former redox system was hence experimentally investigated in the present research at the 0.5 to 250 g scale in isothermal thermogravimetry, an electrically heated furnace, and a concentrated solar reactor. Over 30 successive oxidation/reduction cycles were assessed, and the H2 production efficiencies exceeded 98 % for the coprecipitated reactant after these multiple cycles. Tentative economics using a coprecipitated reactant revealed that 120 cycles are needed to achieve a 1 € per kg H2 cost. Improving the cheaper ball-milled reactant could reduce costs by approximately 30 %. The initial results confirm that future research is important.

Investigating H2 production by MnFe2O4/Na2CO3/H2O redox cycles, using different reactants. Using the more efficient coprecipitated reactant, production costs will be ∼1€ per kg H2, if 120 cycles are achieved. Improving the cheaper ball-milled reactant is recommended.  相似文献   
60.
Prostaglandin E1 (PgE1) was administered intravenously to 26 patients with decompensated chronic obstructive pulmonary disease (COPD) in order to investigate the effects on hemodynamics and blood gases of a reduction in pulmonary hypertension in this condition. In the first 10 patients, PgE1 at 0.02 microgram/kg/min decreased pulmonary and systemic pressures, respectively, by 20 and 7%, increased cardiac index (CI) and oxygen delivery to the tissues (TO2), and did not affect blood gases. In the next 9 patients, PgE1 at 0.04 microgram/kg/min decreased pulmonary and systemic pressures, respectively, by 24 and 14%, increased CI and TO2, slightly decreased arterial oxygenation, and did not affect mixed venous blood gases. Side effects, consisting in facial flush, headache, and malaise occurred in 4 of these patients. In the last 7 patients who were artificially ventilated, PgE1 at 0.02 microgram/kg/min increased CI and TO2 but had no effect on vascular pressures and blood gases. Prostaglandin E1 was also given intravenously to 7 healthy subjects breathing 12.5% O2 in N2 for 10 min. Hypoxic pulmonary vasoconstriction was not inhibited by PgE1, even at the highest dosage of 0.04 microgram/kg/min, which caused a flush of the skin, headache, and malaise in all the subjects. Infusion of PgE1 reduces the pulmonary hypertension secondary to decompensated COPD. At adequate dosage, this effect can be obtained with minimal systemic vasodilation and no alteration in the gas exchange function of the lungs, which may be due to preservation of pulmonary vascular tone adaptation to hypoxia. The vasodilating activity fo PgE1 appears to be blunted during artificial ventilation.  相似文献   
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