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91.
Exacerbations of pulmonary symptoms in patients with cystic fibrosis must be recognised early and treated vigorously in order to maintain pulmonary function and relieve symptoms. The aetiology of these exacerbations is discussed, together with the options for treatment and the evidence to support treatment choices. 相似文献
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93.
Alastair JS Webb Amy Lawson Linxin Li Sara Mazzucco Peter M Rothwell for the Oxford Vascular Study Phenotyped Cohort 《Journal of cerebral blood flow and metabolism》2021,41(6):1463
Cerebral arterial pulsatility is strongly associated with cerebral small vessel disease and lacunar stroke yet its dependence on central versus local haemodynamic processes is unclear. In a population-based study of patients on best medical managment, 4–6 weeks after a TIA or non-disabling stroke, arterial stiffness and aortic systolic, diastolic and pulse pressures were measured (Sphygmocor). Middle cerebral artery peak and trough flow velocities and Gosling’s pulsatility index were measured by transcranial ultrasound. In 981 participants, aortic and cerebral pulsatility rose strongly with age in both sexes, but aortic diastolic pressure fell more with age in men whilst cerebral trough velocity fell more in women. There was no significant association between aortic systolic or diastolic blood pressure with cerebral peak or trough flow velocity but aortic pulse pressure explained 37% of the variance in cerebral arterial pulsatility, before adjustment, whilst 49% of the variance was explained by aortic pulse pressure, arterial stiffness, age, gender and cardiovascular risk factors. Furthermore, arterial stiffness partially mediated the relationship between aortic and cerebral pulsatility. Overall, absolute aortic pressures and cerebral blood flow velocity were poorly correlated but aortic and cerebral pulsatility were strongly related, suggesting a key role for transmission of aortic pulsatility to the brain. 相似文献
94.
Nigel W Crawford Anthony G Catto-Smith Mark R Oliver Donald JS Cameron Jim P Buttery 《BMC gastroenterology》2011,11(1):1-8
Background
Pre-existing polyps, especially large polyps, are known to be the major source for colorectal cancer, but there is limited available information about factors that are associated with polyp size and polyp growth. We aim to determine factors associated with polyp size in different age groups.Methods
Colonoscopy data were prospectively collected from 67 adult gastrointestinal practice sites in the United States between 2002 and 2007 using a computer-generated endoscopic report form. Data were transmitted to and stored in a central data repository, where all asymptomatic white (n = 78352) and black (n = 4289) patients who had a polyp finding on screening colonoscopy were identified. Univariate and multivariate analysis of age, gender, performance site, race, polyp location, number of polyps, and family history as risk factors associated with the size of the largest polyp detected at colonoscopy.Results
In both genders, size of the largest polyp increased progressively with age in all age groups (P < .0001). In subjects ≥ 80 years the relative risk was 1.55 (95% CI, 1.35-1.79) compared to subjects in the youngest age group. With the exception of family history, all study variables were significantly associated with polyp size (P < .0001), with multiple polyps (≥ 2 versus 1) having the strongest risk: 3.41 (95% CI, 3.29-3.54).Conclusions
In both genders there is a significant increase in polyp size detected during screening colonoscopy with increasing age. Important additional risk factors associated with increasing polyp size are gender, race, polyp location, and number of polyps, with polyp multiplicity being the strongest risk factor. Previous family history of bowel cancer was not a risk factor. 相似文献95.
三叶因子与胃黏膜保护的研究进展 总被引:1,自引:0,他引:1
三叶因子家族是一群主要由胃肠道黏液细胞分泌的小分子多肽.其共同特征为均含一特殊的P结构域及三叶状结构.这种稳定的结构使三叶因子家族具有明显的抗蛋白酶水解、酸消化及耐热特性,因而能在消化道复杂的环境中保持生物活性.目前在哺乳动物体内发现的有pS2/TFF1、SP/TFF2和ITF/TFF3三种,它们具有黏膜保护与修复、肿瘤抑制、信号传导、调节细胞凋亡等功能.本文阐述了三叶因子家族发现的历史,并初步探讨了其作用.同时也对三叶因子受体这一热点的研究现状进行总结. 相似文献
96.
McManus TE Marley AM Baxter N Christie SN Elborn JS Heaney LG Coyle PV Kidney JC 《Respiratory medicine》2007,101(10):2084-2090
INTRODUCTION: The COPD airway is infiltrated with CD8+ T cells, which has led to a virus being implicated in its pathogenesis. Some investigators have suggested a role for the persistence of the adenovirus E1A in bronchial epithelial cells. We examined respiratory tract specimens from COPD patients for the presence of E1A DNA and mRNA using real-time PCR. METHODS: Nucleic acid extraction was performed on sputum specimens from patients with COPD. Copy numbers for GAPDH, and adenovirus 5 E1A DNA and mRNA were determined using a quantitative real-time PCR assay. All samples were screened for the adenovirus hexon gene using nested PCR. RESULTS: One hundred and seventy-one patients, 80 male, aged 68.9+/-9.8 years with COPD were recruited. One hundred and thirty-six were seen during an exacerbation when admitted to hospital, 33 of whom were reviewed when clinically stable along with an additional 35 stable COPD patients. Ten patients in the exacerbation group were positive for the adenovirus hexon gene (7%), as were four in the stable group (6%). Only two patients in the exacerbation group were positive for adenovirus 5 E1A. Only one patient in the stable COPD group had detectable E1A DNA/mRNA and also tested positive for the adenovirus hexon gene. CONCLUSION: Adenovirus is detected in similar frequencies in exacerbated and stable COPD patients. Adenovirus E1A DNA is infrequently detected in respiratory secretions from patients with COPD. Our data suggest that the persistence of adenovirus 5 E1A in lung cells of sputum samples in patients with COPD occurs infrequently. 相似文献
97.
Predictors of mortality in adults with cystic fibrosis 总被引:1,自引:0,他引:1
Courtney JM Bradley J Mccaughan J O'Connor TM Shortt C Bredin CP Bradbury I Elborn JS 《Pediatric pulmonology》2007,42(6):525-532
Assessment of prognostic indicators in patients with cystic fibrosis (CF) is important. The study's aim was to assess the relative contribution of gender, genetics and microbiology on survival in adults with CF. Adult patients were studied from 1995 to 2005 and data collected included FEV(1) (%predicted), body mass index (BMI), genetics, and microbiology. Data was available on 183 patients in 1995. Forty-five patients died in the subsequent 10 years. Patients who died during the study had lower mean (SD) FEV(1) %predicted in 1995 when compared to those remaining alive, 41.5 (15.2)% versus 69.8 (23.2)% predicted, respectively, P<0.001 and they had lower mean (SD) BMI in 1995, 19.2 (3.3) kg/m(2) in comparison to those remaining alive, 20.7 (3.4) kg/m(2), P=0.008. The proportion of patients infected with Pseudomonas aeruginosa and Burkholderia cepacia complex was higher in the group who died during the study compared to those remaining alive, odds ratio 20.9 P<0.0001 and 7.1 P<0.0001, respectively. The presence of the Delta F508 homozygous mutation did not alter survival, P=0.3. Patients infected with either P.aeruginosa or B.cepacia complex had reduced survival compared to those without infection, P=0.01 and P<0.0001, respectively. FEV(1)% (P<0.0001), infection with P.aeruginosa (P=0.005) or B.cepacia complex (P=0.03) were the only significant predictors of mortality. This study demonstrates adults who died were more likely to have worse lung function and be infected with either P.aeruginosa or B.cepacia complex. FEV(1)% and infection with P.aeruginosa or B.cepacia complex were the most significant predictors of survival in adults with CF. 相似文献
98.
99.
STUDY OBJECTIVES: To compare pulmonary exacerbations with single and multiple organisms in patients with chronic Burkholderia cepacia infection. DESIGN: Data was collected over a 23-month period and for each of the patients two episodes of pulmonary exacerbation were identified, one with B. cepacia isolated as the sole respiratory pathogen and the other with one or more coinfecting organisms grown from the sputum culture. SETTING: Regional tertiary referral center for Respiratory Medicine and Adult Cystic Fibrosis Center for Northern Ireland, Belfast City Hospital. PATIENTS: Adult (over 16 years) CF patients with chronic (more than 4 years) B. cepacia complex infection who attended the Belfast City Hospital between January 1997 and November 1998. MEASUREMENTS: Forced expiratory volume in 1s, forced vital capacity, forced expiratory flow rate 25-75, C-reactive protein, leucocyte count and body mass index were measured before and after two weeks of treatment and analysed for any differences in change between the two episodes. RESULTS: All variables in both groups improved following treatment except for body mass index, which remained unchanged. No significant differences between the measurements were identified on comparison of single (monomicrobial) and multiple (polymicrobial) isolate episodes. CONCLUSION: Patients with chronic B. cepacia infection who develop a pulmonary exacerbation improve, as reflected by clinical and biochemical markers, following IV antibiotic treatment. Pulmonary exacerbations with multiple organisms are no more severe than those where only B. cepacia is isolated. 相似文献
100.
Background: Bronchiectasis is poorly characterised in secondary care. Methods: Over 6 months, 410 bronchiectasis patients attended our clinics. One hundred randomly selected patients were characterised in detail. Results: Patients had a mean and standard error of mean (S.E.M.) age of 57 (2) years and a median and interquartile range (IQR) of three (two to four) reviews in the last 12 months. Aetiologies identified included tuberculosis (n=15), childhood pneumonia (n=7), fibrosis (n=6), connective tissue disease (n=6), whooping cough (n=5), childhood measles (n=4) and others (n=5). There was widespread use of inhaled therapy. Treatments included oral antibiotics (n=77), corticosteroid courses (n=27) and intravenous antimicrobials (n=27, 12 domicillary) in the last year. Thirty patients had hospital admissions (13 because of the inability to administer domicillary antibiotics). Haemophilus influenzae and Pseudomonas spp. were the commonest bacterial isolates. Patients culturing Pseudomonas spp. were older and had had more reviews and intravenous antibiotic courses. Conclusions: Bronchiectasis imposes a considerable burden on hospital services. Patients culturing Pseudomonas spp. impose a greater burden. Aetiology is often unknown. Therapies with unproven benefit are often used. 相似文献