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61.
Structural and mechanical adaptations in response to sustained changes in arterial pressure were studied on abdominal aorta of the male rat. Two models were used: 1. Aortic ligature (L), immediately below the renal arteries producing hypotension distal to the knot (duration before sacrifice 6 weeks or 3 months). 2. One-clip renal hypertensive rats (H) (duration 6 weeks). Normotensive sham-operated rats (C) served as controls. At sacrifice mean tail artery pressure was L: 58 +/- 1, C: 110 +/- 3, and H: 163 +/- 5 mmHg (SE, N=6). Segments of abdominal aorta were mounted in vitro for determination of their length-tension relations (activation: High-K+ solution with 2.5 mM Ca2+). At end of experiments the vessels were supramaximally stimulated at optimal circumference (1o) for active force (activation: High-K+ solution with 10 mM Ca2+, and 10(-5) M noradrenaline), and then fixated for light and electron microscopy. Passive and active length-tension relations were shifted towards lower and higher circumference values for hypo- and hypertensive vessels, respectively. The 1o values were L: 3.60 +/- 0.13, C: 4.44 +/- 0.19, and H: 4.91 +/- 0.29 mm. The media thickness at 1o was reduced in L: 56.0 +/- 3.3, and increased in H: 81.3 +/- 2.4 compared to C: 73.4 +/- 1.8 micron. Maximal active wall stress was L: 46.6 +/- 9.8, C: 74.2 +/- 7.0, and H: 83.8 +/- 7.7 mN/mm2. Intracellular volume (ICV) in the media was L: 30 +/- 2, C: 45 +/- 3, and H: 44 +/- 1% (n=4 for each).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
62.
Jonsson A Lindén M Lindgren M Malmqvist LA Bäcklund Y 《Medical & biological engineering & computing》2005,43(5):541-547
Pressure sores are a current problem in hospitals and care of the elderly, leading to protracted hospital stays and a high
care burden. The trauma for the patients is severe, and the cost of pressure sore prevention and treatment, is considerable.
Antidecubitus mattresses are used for prevention and in treatment, but they also contribute to the cost of treating pressure
sores. The problem highlighted in the review is that the mattresses' effectiveness in preventing and treating pressure sores
has not been sufficiently evaluated. When antidecubitus mattresses are evaluated, it is often only with regard to aspects
of the interface pressure and the mattresses' ability to redistribute the pressure. The review points out the important observation
that, to be able to evaluate the efficacy of the antidecubitus mattress, the mattress's effect on tissue viability needs to
be studied. The parameters that ought to be considered when evaluating a support surface are: interface pressure, pressure
and blood flow distribution, temperature and humidity in the skin-support surface interface. The authors propose that the
effect on tissue viability of external loading can be assessed by simultaneous measurement of the interface pressure and tissue
perfusion. 相似文献
63.
Climacteric symptoms and knowledge about hormone replacement therapy among Hong Kong Chinese women aged 40-60 years 总被引:1,自引:0,他引:1
OBJECTIVES: To evaluate the use of hormone replacement therapy (HRT), the prevalence of climacteric symptoms, and the knowledge about HRT. METHODS: A prospective study was conducted by telephone interview among a randomly selected population-based sample of 978 Hong Kong Chinese women aged 40-60 years. RESULTS: Of 414 women with a history of either natural or surgical menopause, 22 (5.3%) and 17 (4.1%), respectively, were either past or current users of HRT. The climacteric symptom scores of premenopausal women were significantly lower than those of perimenopausal women, but were comparable with those of postmenopausal women. The commonest climacteric symptom was 'muscle and joint pains' which was reported in 553 (56.6%) women, while only 228 (23.3%) and 151 (15.4%) women reported hot flushes and night sweating, respectively. Moreover, only 230 (23.5%) women realized that HRT could relieve menopausal symptoms and only 33 (3.4%) women were aware that HRT was protective against osteoporosis. In general, women with more climacteric symptoms, who had ever used HRT, and those with higher education level and higher family income, had better knowledge about HRT. CONCLUSIONS: Postmenopausal Hong Kong Chinese women have a low HRT usage rate and the majority of them are lacking of the knowledge about HRT. 相似文献
64.
BACKGROUND: There has thus far been no empirical research on the occurrence of antenatal psychiatric morbidity in Chinese population. Epidemiological studies in western societies generally show that depressive episodes occur in 10-20% of pregnant women. Longitudinal studies have demonstrated that antenatal depression is one of the most powerful predictors of postnatal depression. There is also a growing literature that shows that antenatal psychological distress can adversely affect maternal and foetal well being. METHODS: At 38 weeks of pregnancy, 238 consecutive women were invited to return for psychiatric assessment. The participants were interviewed using the non-patient version of the Structured Clinical Interview for DSM-IV (SCID-NP). RESULTS: Seventy women (29%) declined to participate, and another 11 (5%) defaulted the SCID interview. Among the 157 women interviewed, the 1-month prevalence of antenatal depression was 4.4%. The 1-month prevalence of all psychiatric diagnoses was 6.4%. The prevalence of antenatal depression and all psychiatric diagnoses for the entire pregnancy was 6.4% and 8.3%, respectively. LIMITATIONS: About a third of eligible subjects did not participate in the study. CONCLUSIONS: A significant proportion of Chinese women suffer from psychiatric morbidity during pregnancy. Depressive disorders are by far the commonest morbidity in the study population. Given the scope of the morbidity and the potential impact on obstetric and neonatal outcomes, early screening and treatment are warranted. 相似文献
65.
Occurrence of leukoplakia and some other oral white lesions among 20 333 adult Swedish people 总被引:1,自引:0,他引:1
Tony Axéll 《Community dentistry and oral epidemiology》1987,15(1):46-51
Among 20,333 people aged 15 yr or above, the prevalences of oral white lesions were calculated based on a partly new classification. The total prevalences were: cheek and lip biting 5.1%, smoker's palate 1.1%, frictional white lesion 5.5%, snuff dipper's lesion 8.0%, preleukoplakia 6.4% and leukoplakia 3.6%. If all these lesions were pooled, the prevalence was 24.8% and if only the entities cheek and lip biting and smoker's palate were excluded it became 20.1%. If weak "preleukoplakic" lesions were excluded from the latter figure the prevalence for marked whitish lesions was 13.8%. Etiologic and clinical subgroups of leukoplakia showed the following prevalences: using the etiologic subgroups, idiopathic leukoplakia 0.7% and tobacco-associated leukoplakia 2.9%; using the clinical subgroups, homogeneous leukoplakia 3.5% and non-homogeneous leukoplakia 0.3%. The intraoral location pattern of leukoplakias was preponderant in the commissural and buccal areas. However, the idiopathic leukoplakias showed a somewhat more even distribution and thus a more similar distribution to that of oral cancer. 相似文献
66.
Don V. Jackson Jr. V. Sagar Sethi Tony R. Long Hyman B. Muss Charles L. Spurr 《Cancer chemotherapy and pharmacology》1984,13(2):114-119
Summary The pharmacokinetics of vindesine were investigated during treatment of 15 patients with progressive malignancies refractory to conventional treatment. Patients were administered one of three IV dose schedules: 3.0 mg/m2 bolus injection, 1.2 mg/m2/day infusion for 5 days, or 2.0 mg/m2/day infusion for 2 days. Concentrations of the drug in the serum and urine were determined by radioimmunoassay. Serum concentrations were highest (5×10-7 M) in patients receiving a bolus injection, but fell to nondetectable levels by 48 h in four of five patients (terminal t1/2 15.0±9.4 h). Compared with bolus injection, 1.2-to 1.4-fold greater areas under the blood concentration curve were observed during infusions of 2.0 mg/m2 and 1.2 mg/m2. Whereas steady-state concentrations (1×10-8 M) were maintained throughout the infusion of 1.2 mg/m2/day progressively increasing serum levels were observed during the infusion of 2.0 mg/m2/day. Serum concentrations fell rapidly following discontinuation of the 2.0-mg/m2 infusion, but were somewhat more sustained in the 1.2-mg/m2 infusion group. The average urinary excretion was similar for each dose-schedule (8%–11% of the total dose). The pharmacokinetics of vindesine are influenced by variations in dose schedule. 相似文献
67.
68.
Tony Wawina-Bokalanga Bert Vanmechelen Valentine Lhermitte Joan Martí-Carreras Valentijn Vergote Fara Raymond Koundouno Joseph Akoi-Bor Ruth Thom Tom Tipton Kimberley Steeds Kita Balla Moussa Ablam Amento Lies Laenen Sophie Duraffour Martin Gabriel Paula Ruibal Yper Hall Mandy Kader-Kond Stephan Günther Guy Baele Cesar Muoz-Fontela Johan Van Weyenbergh Miles W. Carroll Piet Maes 《Emerging infectious diseases》2021,27(1):76
We investigated the genetic profiles of killer cell immunoglobulin-like receptors (KIRs) in Ebola virus–infected patients. We studied the relationship between KIR–human leukocyte antigen (HLA) combinations and the clinical outcomes of patients with Ebola virus disease (EVD). We genotyped KIRs and HLA class I alleles using DNA from uninfected controls, EVD survivors, and persons who died of EVD. The activating 2DS4–003 and inhibitory 2DL5 genes were significantly more common among persons who died of EVD; 2DL2 was more common among survivors. We used logistic regression analysis and Bayesian modeling to identify 2DL2, 2DL5, 2DS4–003, HLA-B-Bw4-Thr, and HLA-B-Bw4-Ile as probably having a significant relationship with disease outcome. Our findings highlight the importance of innate immune response against Ebola virus and show the association between KIRs and the clinical outcome of EVD. 相似文献
69.
Andersen Patrick Mizdrak Anja Wilson Nick Davies Anna Bablani Laxman Blakely Tony 《Population health metrics》2022,20(1):1-12
The mortality pattern from birth to age five is known to vary by underlying cause of mortality, which has been documented in multiple instances. Many countries without high functioning vital registration systems could benefit from estimates of age- and cause-specific mortality to inform health programming, however, to date the causes of under-five death have only been described for broad age categories such as for neonates (0–27 days), infants (0–11 months), and children age 12–59 months. We adapt the log quadratic model to mortality patterns for children under five to all-cause child mortality and then to age- and cause-specific mortality (U5ACSM). We apply these methods to empirical sample registration system mortality data in China from 1996 to 2015. Based on these empirical data, we simulate probabilities of mortality in the case when the true relationships between age and mortality by cause are known. We estimate U5ACSM within 0.1–0.7 deaths per 1000 livebirths in hold out strata for life tables constructed from the China sample registration system, representing considerable improvement compared to an error of 1.2 per 1000 livebirths using a standard approach. This improved prediction error for U5ACSM is consistently demonstrated for all-cause as well as pneumonia- and injury-specific mortality. We also consistently identified cause-specific mortality patterns in simulated mortality scenarios. The log quadratic model is a significant improvement over the standard approach for deriving U5ACSM based on both simulation and empirical results. 相似文献
70.
Patawut Bovonratwet Tony S. Shen Wasif Islam Peter K. Sculco Douglas E. Padgett Edwin P. Su 《The Journal of arthroplasty》2021,36(6):2016-2023
BackgroundMultiple stakeholders are interested in improving patient experience after primary total hip arthroplasty due to shifts toward patient-centered care. Patient free-text narratives are a potentially valuable but largely unexplored source of data.MethodsThe records of 383 patients who underwent primary total hip arthroplasty between August 2016 and August 2019 were combined with vendor-supplied patient satisfaction data, which included patient free-text comments and the Press Ganey satisfaction survey. A total of 1295 patient comments were analyzed for sentiment, and negative comments were categorized into nine themes. Postoperative outcomes, patient-reported outcome measures, and traditional measures of satisfaction were compared between patients who provided a negative comment vs those who did not. Multivariable regression was used to determine perioperative variables associated with providing a negative comment.ResultsOf the 1295 patient comments: 54% were positive, 24% were negative, 10% were mixed, and 12% were neutral. Top two themes of negative comments were room condition (25%) and inefficient communication (23%). There were no differences in studied outcomes (eg. peak pain intensity, length of stay, or improvements in hip injury and osteoarthritis outcome scores Jr. and pain visual analog scale scores at 6-week follow-up) between those who provided negative comments vs those who did not (P > .05). However, patients who made negative comments were less likely to recommend their hospital care to peers (P < .001). Finally, patients who had >2 allergies (P = .024) were more likely to provide negative comments.ConclusionThe present study demonstrates that patient satisfaction appears not to be a reliable sole proxy for traditional objective outcome measures of pain relief and functional improvement. 相似文献