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1.
To explore if change in the extent of emphysema correlated with change in lung function, the effect of resection of emphysematous tissue was studied by computed tomography (CT) densitometry. In addition, the current authors studied how surgery-induced change in emphysema related to lung density in control subjects. In total, 30 patients (14 females; mean+/-sd age 59+/-10 yrs) with severe emphysema before and 3 months after lung volume reduction surgery (LVRS), 48 patients with moderate emphysema and 76 control subjects were investigated. Lung density (15th percentile point) of both lungs and heterogeneity of lung density between 12 isovolumetric partitions in each lung were calculated from chest CT images. The 15th percentile point and its heterogeneity could distinguish controls from subjects with moderate emphysema with a sensitivity and specificity of >95%. LVRS significantly increased lung density by 5.0+/-10.9 g.L(-1) (n=30). Improvement in the diffusing capacity of the lung for carbon monoxide and in residual volume significantly correlated with an increase in lung density (n=20 and 28, respectively). Change in forced expiratory volume in one second did not correlate with change in lung density. In conclusion, lung density 15th percentile point is a valuable surrogate marker for detection of both the extent of and reduction in emphysema.  相似文献   
2.
Primary pulmonary hypertension in HIV infection   总被引:6,自引:0,他引:6  
R Speich  R Jenni  M Opravil  M Pfab  E W Russi 《Chest》1991,100(5):1268-1271
A prospective evaluation of 74 human immunodeficiency virus (HIV)-infected patients with cardiopulmonary complaints revealed six patients (8.1 percent) with pulmonary hypertension with elevated right ventricular systolic over right atrial pressure of 58 +/- 8 mm Hg (range, 49 to 66 mm Hg), as documented by Doppler echocardiography. A thromboembolic cause was excluded by normal lung perfusion scans. Electrocardiographic and roentgenographic features of pulmonary hypertension were present in five patients. Two patients died three and nine months after diagnosis of pulmonary hypertension. Autopsy revealed plexogenic pulmonary arteriopathy in both. The observation of six patients with primary pulmonary hypertension (PPH) in a cohort of 1,200 HIV-infected subjects corresponding to an incidence of 0.5 percent is striking and suggests a possible association of PPH with HIV infection.  相似文献   
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Since lung transplant recipients are susceptible to infections and inhaled pollution, many centers warn against pets. However, data supporting this recommendation are lacking. Our program is less restrictive regarding pets. This study, for the first time, investigates the association of pets with physiological and psychological parameters in these patients. A questionnaire concerning pets was sent to 104 lung transplant recipients. Lung function tests, levels of exhaled nitric oxide (FE(NO)), need for antibiotic treatments and hospitalizations, creatinine clearance, body mass index (BMI) and demographic data were assessed. Additionally, the questionnaire of life satisfaction (FLZ), a question on summarized life satisfaction (LS), the life orientation test (LOT), the hospital anxiety depression scale (HADS) and the social support questionnaire (F-SozU) were assessed. Response rate was 86%. Fifty-two percent defined themselves as pet owners, whereas 48% did not. The two groups did not differ in demographic or physiological data. Significant differences in FLZ (79/65, p = 0.04), in LS (4.3/3.9, p = 0.01), LOT (32/29, p = 0.006) and F-SozU (4.5/4.2, p = 0.04) were found in favor of pet owners. In lung transplant recipients keeping pets the frequency of somatic complications is not higher compared to lung transplant recipients without pets. After lung transplantation, pets are associated with a better quality of life.  相似文献   
5.
Basic mechanisms underlying the tolerance and reaction of the central nervous system to ionizing radiation are not known precisely. We investigated the possibility of a change in blood-brain barrier (BBB) function as a causative factor for early delayed whole-brain radiation-induced cerebral dysfunction. Rats were exposed to conventional fractionation (200 cGy/d, 5 d/wk; total dose, 4000 cGy). BBB changes were assessed by means of the quantitative 14C-alpha-aminoisobutyric acid technique and electron microscopy. Studies of the passage of horseradish peroxidase across the BBB permitted comparative quantitative isotopical and qualitative morphological data. Experiments were carried out 2 to 3 weeks after the completion of the radiation exposure. The transport of 14C-alpha-aminoisobutyric acid across the BBB increased significantly in cerebral cortex and cerebellar gray matter, averaging 1.3 to 1.5 times over the normal values. Electron microscopy disclosed an intense vesicular response of the cortical microvascular endothelium that occurred without the opening of the tight junctions and resulted in an intense transport of HRP across the intact endothelium. The present data indicate that moderate doses of whole-brain radiation induce well-defined changes in BBB function, which possibly are involved in the pathogenesis of radiation-induced cerebral dysfunction in humans.  相似文献   
6.
Nitrous acid, a component of photochemical smog and a common indoor air pollutant, may reach levels of 100 ppb where gas stoves and unvented portable kerosene heaters are used. Nitrous acid is a primary product of combustion and may also be a secondary product by reaction of nitrogen dioxide with water. Because the usual assays for nitrogen dioxide measure several oxides of nitrogen (including nitrous acid) together, previous studies of indoor nitrogen dioxide may have included exposure to and health effects of nitrous acid. To assess the respiratory effects of nitrous acid exposure alone, we carried out a double-blinded crossover chamber exposure study with 11 mildly asthmatic adult subjects. Each underwent 3-hr exposures to 650 ppb nitrous acid and to filtered room air with three 20-min periods of moderate cycle exercise. Symptoms, respiratory parameters during exercise, and spirometry after exercise were measured. A statistically significant decrease in forced vital capacity was seen on days when subjects were exposed to nitrous acid. This effect was most marked at 25 min and 85 min after exposure began. Aggregate respiratory and mucous membrane symptoms were also significantly higher with nitrous acid. We conclude that this concentration and duration of exposure to nitrous acid alters lung mechanics slightly, does not induce significant airflow obstruction, and produces mild irritant symptoms in asthmatics.  相似文献   
7.
HIV cross-sectional studies were conducted among high-risk populations in 9 countries of South America. Enzyme-linked immunosorbent assay screening and Western blot confirmatory testing were performed, and env heteroduplex mobility assay genotyping and DNA sequencing were performed on a subset of HIV-positive subjects. HIV prevalences were highest among men who have sex with men (MSM; 2.0%-27.8%) and were found to be associated with multiple partners, noninjection drug use (non-IDU), and sexually transmitted infections (STIs). By comparison, much lower prevalences were noted among female commercial sex workers (FCSWs; 0%-6.3%) and were associated mainly with a prior IDU and STI history. Env subtype B predominated among MSM throughout the region (more than 90% of strains), whereas env subtype F predominated among FCSWs in Argentina and male commercial sex workers in Uruguay (more than 50% of strains). A renewed effort in controlling STIs, especially among MSM groups, could significantly lessen the impact of the HIV epidemic in South America.  相似文献   
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We define a solitary pulmonary noncalcified nodule (NPS) as a single focal rounded or ovoid lesion in the lung parenchyma, less than 4 cm in diameter, without associated adenopathy, atelectasis or pneumonia. An NPS, in the absence of a known primary malignancy, can be lung cancer (NPSM), a metastasis of unknown origin (NPSMT), or a benign lesion (NPSB). The best approach to the management of NPS and the value of CT are still controversial and uncertain. The finding on cross-section CT of a bronchus leading directly to, or contained within, the nodule is called "positive CT bronchus sign" (CT-BS). Our study was aimed at investigating the usefulness of CT bronchus sign, as studied on thin-slice (2 mm thick) CT sections, in order to establish the most appropriate diagnostic sequence in patients with solitary noncalcified pulmonary nodules (NPS). We evaluated 47 NPS (9 NPSB, 34 NPSM and 4 NPSMT) with thin-slice CT to detect the presence of CT bronchus sign. Seventeen cases had CT-BS (15 NPSM; 1 NPSB; 1 NPSMT); of them, 13 were diagnosed by means of transbronchial biopsy and brushing (TBB). Only one case (NPSM) of the 30 (19 NPSM; 3 NPSMT; 8 NPSB) without CT-BS, was diagnosed by TBB. TBB was negative in the 9 NPSB. The CT-BS is not pathognomonic of malignancy; in fact, the sign was observed in NPSB (one tuberculoma) too. Our results suggest that the CT bronchus sign is valuable in predicting the success of TBB in malignant solitary pulmonary nodules. On the other hand, it seems to be useless for NPSB. Therefore, to establish the most appropriate diagnostic sequence, thin-section CT should be performed in each patient with peripheral noncalcified lung lesions to plan whether TBB or transthoracic needle aspiration should come next. If biopsy results are poor, either surgery or the "wait and watch for growth" approaches can be suggested. The choice can be guided by the presence of predisposing factors for cancer or infection.  相似文献   
10.
AimTo comprehensively describe intellectual and executive functioning (EF) in people with dyskinetic cerebral palsy (DCP), by comparing their performance with that of: 1) age- and sex-matched typically developing controls (TDC); and 2) participants with spastic cerebral palsy (SCP) matched for age, sex, term/preterm and gross motor function classification system (GMFCS).MethodThis cross-sectional study was conducted by the University of Barcelona in collaboration with five institutions. Participants were people with DCP (n = 52; 24 females, median age 20.5 y: 5mo, interquartile range [IQR] = 13.75 y: 7mo; GMFCS I–V). As comparison groups, participants with SCP (n = 20; 10 females, median age = 20.5 y: 5.5mo, IQR = 13.75 y 9mo; GMFCS I–V) and TDC (n = 52; 24 females, median age = 20 y: 4mo, IQR = 12 y 7mo) were included. Intelligence and EF were assessed using common tests in all participants.ResultsBoth CP groups had lower intelligence than TDC and performed poorer in almost all EF tasks. Intelligence was higher in DCP than SCP (z = ?2.51, p = 0.01). Participants with DCP also performed significantly better in goal-setting tasks (z = 2.27, p = 0.03) and information processing (z = ?2.54, p = 0.01) than those with SCP.ConclusionPeople with DCP present lower general intellectual functioning and poorer EF across multiple domains than typically developing controls. People with DCP have higher general intellectual functioning and better EF than people with SCP when levels of motor severity are similar.  相似文献   
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