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71.
Guidelines recommend that patients with COPD are stratified arbitrarily by baseline severity (FEV1) to decide when to initiate combination treatment with a long-acting β2-agonist and an inhaled corticosteroid. Assessment of baseline FEV1 as a continuous variable may provide a more reliable prediction of treatment effects. Patients from a 1-year, parallel-group, randomized controlled trial comparing 50 μg salmeterol (Sal), 500 μg fluticasone propionate (FP), the combination (Sal/FP) and placebo, (bid), were categorized post hoc into FEV1 <50% and FEV1 ≥50% predicted subgroups (n=949/513 respectively). Treatment effects on clinical outcomes – lung function, exacerbations, health status, diary card symptoms, and adverse events – were investigated. Treatment responses based on a pre-specified analysis explored treatment differences by severity as a continuous variable. Lung function improved with active treatment irrespective of FEV1; Sal/FP had greatest effect. This improvement appeared additive in milder disease; synergistic in severe disease. Active therapy significantly reduced exacerbation rate in patients with FEV1 <50% predicted, not in milder disease. Health status and breathlessness improved with Sal/FP irrespective of baseline FEV1; adverse events were similar across subgroups. The spirometric response to Sal/FP varied with baseline FEV1, and clinical benefits were not restricted to patients with severe disease. These data have implications for COPD management decisions, suggesting that arbitrary stratifications of baseline severity are not necessarily indicative of treatment efficacy and that the benefits of assessing baseline severity as a continuous variable should be assessed in future trials.  相似文献   
72.
Summary. During the last decade it has been customary to estimate pulmonary epithelial permeability (P-P) as the pulmonary clearance of inhaled nebulized 99mTc-DTPA from a time-activity (t-a) curve registered externally by monitoring over the chest. The t-a curve, however, is not defined by the degree of P-P alone but also by factors such as the deposition of the 99mTc-DTPA in the lungs. To avoid these problems a plasma sample method was derived. It describes P-P by the mean transit time (t?) for the transport of 99mTc-DTPA across the pulmonary epithelial membrane, t? (L). The calculation of t? (L) involves two steps. Following the inhalation of Tc-DTPA the plasma t-a curve is defined and used to calculate t? for the transport for 99mTc-DTPA across the pulmonary epithelial membrane, through the E?V and until elimination by the kidneys, t? (L+ECV). Subsequently, 99mTc-DTPA is injected as a bolus i.v. and the new t-a curve is used to calculate t? for the transport of 99mTc-DTPA through ECV to the kidneys, t? (ECV). Finally t? (L) is calculated as t? (L) = -t? (L+ECV) t? (ECV). We applied the method in nine non-smoking individuals (median age 25–5 years, range 20–28) and compared the results to t? as calculated from the initial slope of an externally derived t-a curve. The individual t? (L) values were systematically greater than those of the external detection method (P<0·05). It is concluded that the initial slope method overestimates total PCI as measured by the plasma sample method. When choosing between the two methods, special interest should be paid to the inherent problems of the methods.  相似文献   
73.
Leukemic cells from a series of patients with chronic B-lymphocytic leukemia (CLL) were analyzed for their buoyant density on discontinuous Percoll gradients. The density profile varied markedly between different patients and also between samples from different body compartments within the same patient. A good correlation was observed between buoyant density and maturation stage of the leukemic clones as judged by Ig-expression and their reactivity with a panel of monoclonal antibodies. Phorbol-ester-induced changes in the leukemic cells were found to be accompanied by a general decrease in their buoyant density. No correlation between density and clinical parameters such as cell counts, clinical stage and survival could be noted. Buoyant density characterization of leukemic B-cell populations is seen as a useful, rapid and simple marker of compartmentalization within the B-lymphocyte maturation spectrum but its clinical relevance remains to be established.  相似文献   
74.
We report a unique case of coexistingexogenous lipoid pneumonia, endogenous lipoid pneumonia (EU), and pulmonary alveolar proteinosis (PAP) in a 5-year-old patient with severe neurodevelop mental disease. The patient presented with gastroesophageal reflux and presumed chronic lung disease resulting from recurrent aspiration pneumonias and succumbed to respiratory failure. The autopsy showed lipid-laden macrophages and periodic acid-SchiJf9ositive granular matm'al i n alveolar spaces and multilamellated structures within both alveolar macrophages and extracellular debris.

These findings were similar to those in previous reports of coexisting E I P and PAP in the setting of gastroesophageal refux [I] . However, the present case diJfered by the presence of scattered large osmiophilic extracellular lipid vacuob. Besides strengthening the association between EIP and PAP and their relationship to gastroesophageal refux, this case suggests that t h q may arise together with exogenous lipoid pneumonia, through related mechanisms, in the setting of neurodevelopmental disease.  相似文献   
75.
Clinical diagnosis of chronic cholecystitis is made based on diffuse hyperechoic thickening of the gallbladder wall as shown by ultrasonographic examination. We herein report three cases of chronic cholecystitis showing localized hypoechoic thickening of the gallbladder wall that mimicked gallbladder cancer by ultrasonography. Histologically, hypertrophy of the muscularis propria was a common characteristic finding in these three patients. A smooth surface of the inner hypoechoic layer of the thickened wall was considered to be a reliable finding in the differential diagnosis between this type of chronic cholecystitis and gallbladder cancer.  相似文献   
76.
1 病例资料 患者,女,70岁.因跌伤致右髋部疼痛7 d,于2007年2月1日入院.既往有高血压和糖尿病史.入院查体:BP 21.9/12.3 kPa,神志清醒,说话流利,心、肺、腹未见异常.右下肢外旋短缩畸形,右髋有压痛及纵向叩击痛,双下肢无明显肿胀,Homans征阴性.  相似文献   
77.
L-精氨酸对高原肺水肿患者血液流变学的作用   总被引:3,自引:0,他引:3  
目的:探讨雾化吸入左旋精氨酸(L-Arg)对高原肺水肿患者血液流变学的影响。方法:在海拔3700m高原,采用氧气驱动雾化吸入L-Arg,治疗高原肺水肿(HAPE)患者9例(L-Arg组),将吸入低浓度一氧化氮(NO)混合气治疗的另外8例高原肺水肿患者(NO组)作对照,分别测定患者的红细胞压积(HCT)、血液粘度(ηb)、血浆粘度(ηp)、还原粘度(ηr)、红细胞刚性指数(IR)、红细胞变形系数(TK)、红细胞聚集系数(VAI)和血栓形成系数(TFL)等血液流变学指标。结果:NO组和L-Arg组治疗后较治愈前ηb、ηp、ηr、VAI、TFL均降低显著(P〈0.05~0.01),而HCT、TK、IR无统计学差异(P〉0.05);NO组与L-Arg组比较,各指标均无统计学差异(P〉0.01)。结论:L-Arg治疗HAPE有效,通过提高NO水平而改善血液循环,且经济简便,易于推广应用。  相似文献   
78.
Tracheal rupture represents a rare but serious complication of intubation. We discuss a case of a major post-intubation rupture. After investigation with CT scan tracheoscopy and bronchoscopy a low tracheostomy was formed protecting the rupture from pressure changes associated with ventilation. The patient was managed with minimal surgical intervention, low tracheostomy with antibiotic cover and monitoring in the intensive care unit for 24 h before being woken and moved to a ward after 48 h. The patient made a full and uncomplicated recovery and was discharged 2 weeks after the original injury. Most of the literature on the subject is made up of review of case reports that conclude management of such a major tear must be with surgical repair. This however confers significant morbidity and an associated high mortality. We suggest an alternative management protocol.  相似文献   
79.
Despite decreasing mortality rates, morbidity is still high after pancreatic head resection. Comparative data in the United States and Europe show a relationship between hospital volume and mortality. Treatment strategies vary frequently, partially because of the lack of evidence-based data. We performed a multi-institutional analysis in Germany evaluating current numbers, indications, techniques, and complication rates of pancreatic head resection. Questionnaires were completed by seven high-volume surgical departments regarding quantitative and qualitative aspects of pancreatic head resections in the period from 1999 to 2004 (five prospective and two retrospective institutional databases). A total of 1454 pancreatic head resections (944 for malignancy) were reported. Mean annual hospital volume ranged from 14 to 52 (10 to 43 in malignancy). Mortality was between 1.1% and 4.8%, morbidity was between 24% and 46%, and pancreatic leakage was between 9% and 20%. In malignant disease, all centers perform standard lymphadenectomy and regard arterial infiltration as a contraindication for resection. However, the rate of portal vein resection varied from 0% to 28%. No consensus is seen on the type of surgery for malignancy and chronic pancreatitis. After resection for pancreatic cancer less than one fourth of the patients receive adjuvant therapy. The results of our analysis in Germany confirm that pancreatic head resection can be performed with low mortality in specialized units. Variations in indications, operative technique, and perioperative care may demonstrate the lack of evidence-based data and/or personal and institutional experience. The low number of patients receiving adjuvant therapy after resection of pancreatic cancer suggests that more efforts must be made to establish novel adjuvant therapies under randomized study conditions. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation).  相似文献   
80.
The differential diagnoses of persistent nonproductive cough include numerous pulmonary and nonpulmonary organic disorders as well as functional illnesses. Many diseases can cause cough, and several studies have shown asthma among the most common etiologies associated with chronic cough in adult nonsmokers, as well as children. Psychogenic cough and its relationship to asthma and other asthma-like illnesses is complex since distinct maladies with similar features may coexist individually or in combination in any given patient. While chronic cough may occur as a sole presenting manifestation of bronchial asthma in all age groups, recent findings suggest that most children with persistent cough without other respiratory symptoms do not have asthma. Since several organic, as well as functional diseases, may present with persistent cough as their sole manifestation in either adults or children, cough should not be used as a single or major determinant to diagnose and treat asthma, especially when empirically focused therapy trials fail. Given the range of illnesses causing cough, no single management guideline can be expected to be universally effective.  相似文献   
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