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排序方式: 共有1075条查询结果,搜索用时 15 毫秒
1.
Gil Bolotin Frederik H. van der Veen Roberto Lorusso Tamir Wolf Robert Sachner Rona Shofti Jan J. Shreuder Gideon Uretzky 《European journal of cardio-thoracic surgery》2002,21(6):975-980
Objective: Descending and ascending aortomyoplasty are two surgical procedures intended to induce hemodynamic benefits similar to those of the intra-aortic-balloon-pump (IABP). To date, there have been no studies comparing the two surgical techniques. The objective of this study was to compare coronary blood flow augmentation and afterload reduction as produced by descending and ascending aortomyoplasty counterpulsation Methods: Twenty-two mongrel dogs (18–35 kg) underwent IABP application (n=7), descending (n=8), or ascending (n=7) aortomyoplasty. Left anterior descending (LAD) coronary artery blood flow was measured using a Transonic Doppler flow probe. Left ventricular pressure as well as aortic pressures proximal and distal to either the aortomyoplasty site or the IABP position were monitored continuously. Results: Descending aortomyoplasty induced higher elevation in the LAD blood flow during assisted beats (27% from 10.8±4 to 13.8±6 ml/min, P<0.001) than that induced by either ascending aortomyoplasty (19% from 11.7±5 to 14±5 ml/min, P<0.001) or IABP counterpulsation (18% from 8.6±3 to 10.2±4 ml/min, P<0.001). Conversely, while ascending aortomyoplasty reduced the left ventricular end-diastolic pressure by 16% (from 60±18 to 50±22 mmHg, P<0.001), similar to the 16% after load reduction achieved by the IABP counterpulsation, descending aortomyoplasty failed to induce afterload reduction. Conclusions: Descending aortomyoplasty produces higher coronary blood flow augmentation than either ascending aortomyoplasty or IABP. However, afterload reduction comparable to that achieved by IABP was observed only with ascending aortomyoplasty and not with descending aortomyoplasty. 相似文献
2.
R. J. Rona A. V. Swan R. Beech D. M. Wilson F. B. Kavanagh C. Brown C. Axtell S. Mandalia 《Clinical genetics》1992,42(4):186-195
For certain genetic conditions DNA testing identifies carriers and determines the risk status of foetuses, thus helping parents to make more informed prenatal decisions. Data, collected from three genetic centres in England and Wales from August 1986 to July 1990, are used to describe trends in demand for DNA testing, the impact of DNA tests on carrier risk assessment, and the use of DNA tests in relation to pregnancy outcome. Altogether the data include 23,388 subjects and 681 pregnancies in 8738 families divided into five cohorts by year of entry and referral. The most frequent gene disorders referred to the genetic centres are currently being tested or will soon be tested. For these disorders the initial high level of activity has declined and may have reached steady state. Demand for DNA services is high for cystic fibrosis and Duchenne muscular dystrophy, intermediate for Huntington's disease, and low for adult polycystic kidney disease, phenylketonuria and tuberous sclerosis. Based on these findings we suggest that demand for DNA tests will be high in serious, untreatable and slow progressing conditions with early onset; intermediate for conditions affecting intellect and neurological integrity with later onset; and low for treatable, late-onset conditions, or those for which there is evidence of heterogeneity, and variable penetrance. It would be helpful to assess the extent to which this view of demand is confirmed when the new disorders being DNA tested are considered and for the pattern of activity of DNA testing for some types of cancer. Since no DNA centre could offer a fully comprehensive testing service, it is recommended that a structure is created to audit overall activity, assist in policy formulation, and influence supraregional service organisation, in order that the spread of DNA services be planned as effectively as possible. This structure would facilitate monitoring of the evolution of contract specifications agreed by commissioners and providers on a regional basis. 相似文献
3.
The Relationship Between Daily Life Stress and Gastrointestinal Symptoms in Women with Irritable Bowel Syndrome 总被引:3,自引:0,他引:3
Rona L. Levy Kevin C. Cain Monica Jarrett Margaret M. Heitkemper 《Journal of behavioral medicine》1997,20(2):177-193
Research on irritable bowel syndrome (IBS), a functional disorder of the gastrointestinal (GI) system, has linked GI symptoms to stress. This study examined the relationship between daily stress and GI symptoms across women and within woman in IBS patients (n = 26), IBS nonpatients (IBS-NP; n = 23), and controls (n = 26), controlling for menstrual cycle phase. Women (ages 20–45) completed daily health diaries for two cycles in which they monitored daily GI symptoms and stress levels. The Life Event Survey (LES) was used as a retrospective measure of self-reported stress. The across-women analyses showed higher mean GI symptoms and stress in the IBS and IBS-NP groups relative to controls but no group differences in LES scores. The within-woman analyses found a significant and positive relationship between daily stress and daily symptoms in both the IBS-NP and the IBS groups. Controlling for menstrual cycle had no substantial impact on the results. 相似文献
4.
Respiratory illness and home environment of ethnic groups 总被引:4,自引:0,他引:4
R J Melia S Chinn R J Rona 《British medical journal (Clinical research ed.)》1988,296(6634):1438-1441
Factors contributing to differences in the prevalences of respiratory symptoms and diseases among ethnic groups were studied in primary schoolchildren living in 20 inner city areas of England in 1983. The raised prevalences of respiratory symptoms in these groups were compared with results from a national representative sample of children studied in 1982. Data on age, sex, respiratory illness, and social and environmental variables were obtained by questionnaire for 4815 children living in inner cities. The children were classified as white, Afro-Caribbean, Urdu, Gujarati, Punjabi, other Asian, or "other." Significant differences in the prevalence of respiratory conditions were found among the ethnic groups after allowance was made for the effects of interfering variables. Except for asthma all conditions were most prevalent in Afro-Caribbeans and whites. In these two ethnic groups respiratory illness was significantly associated with belonging to a one parent family and the combined use of gas cookers and paraffin heaters at home. Respiratory illness was found to vary in prevalence among ethnic groups but may be perceived differently by different groups. Further studies, measuring lung function, are necessary. 相似文献
5.
Rossoni G Pompilio G Biglioli P Alamanni F Tartara P Rona P Porqueddu M Berti F 《Journal of cardiac surgery》1999,14(5):334-341
BACKGROUND: Previous studies have shown that defibrotide, a polydeoxyribonucleotide obtained by depolymerization of DNA from porcine tissues, has important protective effects on myocardial ischemia, which may be associated with a prostacyclin-related mechanism. The purpose of this study was to investigate the direct effects of defibrotide (given in cardioplegia or after ischemia) on a model of rat heart recovery after cardioplegia followed by ischemia/reperfusion injury. METHODS: Isolated rat hearts, undergoing 5 minutes of warm cardioplegic arrest followed by 20 minutes of global ischemia and 30 minutes of reperfusion, were studied using the modified Langendorff model. The cardioplegia consisted of St. Thomas' Hospital solution augmented with defibrotide (50, 100, and 200 microg/mL) or without defibrotide (controls). Left ventricular mechanical function and the levels of creatine kinase, lactate dehydrogenase, and 6-keto-prostaglandin F1alpha (6-keto-PGF1alpha; the stable metabolite of prostacyclin) were measured during preischemic and reperfusion periods. RESULTS: After global ischemia, hearts receiving defibrotide in the cardioplegic solution (n = 8) manifested in a concentration-dependent fashion lower left ventricular end-diastolic pressure (p < 0.001), higher left ventricular developed pressure (p < 0.01), and lower coronary perfusion pressure (p < 0.001) compared to the control group. After reperfusion, hearts receiving defibrotide in the cardioplegic solution also had, in a dose-dependent way, lower levels of creatine-kinase (p < 0.01), lactate dehydrogenase (p < 0.001), and higher levels of 6-keto-PGF1alpha (p < 0.001) compared to the control group. Furthermore, when defibrotide was given alone to the hearts at the beginning of reperfusion (n = 7), the recovery of postischemic left ventricular function was inferior (p < 0.05) to that obtained when defibrotide was given in cardioplegia. CONCLUSIONS: Defibrotide confers to conventional crystalloid cardioplegia a potent concentration-dependent protective effect on the recovery of isolated rat heart undergoing ischemia/reperfusion injury. The low cost and the absence of contraindications (cardiac toxicity and hemodynamic effects) make defibrotide a promising augmentation to cardioplegia. 相似文献
6.
An immunohistochemical study of androgen, oestrogen and progesterone receptors in the vulva and vagina 总被引:2,自引:0,他引:2
Malcolm B. Hodgins Senior Lecturer Rosemary C. Spike Research Fellow Rona M. Mackie Professor Allan B. MacLean Senior Lecturer † 《BJOG : an international journal of obstetrics and gynaecology》1998,105(2):216-222
Objective Tomap potential sites of sex steroid action in the human vulva.
Methods Monoclonal antibodies to androgen, oestrogen and progesterone receptors were used to stainfrozen sections of vulval skin, vagina and suprapubic skin. A scoring system was devised to comparereceptor distribution in the epidermis and dermis of skin with vaginal epithelium and stroma.
Results Androgen receptors were seen in epidermal keratinocytes, sebaceous glands, sweat glands, hairfollicles and dermal fibroblasts of skin, and epithelial cells and stromal fibroblasts of the vagina. Androgen receptor scores were significantly higher in the epidermis of labia majora and minora thanin vaginal epithelium. Oestrogen receptors were seen in basal and suprabasal cells of vaginalepithelium and epidermis of labia minora but were restricted to basal keratinocytes in true skin.They were seen in stromal fibroblasts and vaginal smooth muscle, and dermal fibroblasts of theskin. Oestrogen receptors were highest in vaginal epithelium and stroma, and lowest insuprapubic skin. Progesterone receptors were seen in vaginal epithelium, fibroblasts and smoothmuscle but not in the vulva. There was no evidence of significant differences in androgen oroestrogen receptor staining in the vulva of pre- or postmenopausal women.
Conclusion The transition from vagina to vulva is marked by an increase in androgen and a decrease inoestrogen and progesterone receptors. This distribution of receptors would indicate a limited role foroestrogen creams on the vulva. 相似文献
Methods Monoclonal antibodies to androgen, oestrogen and progesterone receptors were used to stainfrozen sections of vulval skin, vagina and suprapubic skin. A scoring system was devised to comparereceptor distribution in the epidermis and dermis of skin with vaginal epithelium and stroma.
Results Androgen receptors were seen in epidermal keratinocytes, sebaceous glands, sweat glands, hairfollicles and dermal fibroblasts of skin, and epithelial cells and stromal fibroblasts of the vagina. Androgen receptor scores were significantly higher in the epidermis of labia majora and minora thanin vaginal epithelium. Oestrogen receptors were seen in basal and suprabasal cells of vaginalepithelium and epidermis of labia minora but were restricted to basal keratinocytes in true skin.They were seen in stromal fibroblasts and vaginal smooth muscle, and dermal fibroblasts of theskin. Oestrogen receptors were highest in vaginal epithelium and stroma, and lowest insuprapubic skin. Progesterone receptors were seen in vaginal epithelium, fibroblasts and smoothmuscle but not in the vulva. There was no evidence of significant differences in androgen oroestrogen receptor staining in the vulva of pre- or postmenopausal women.
Conclusion The transition from vagina to vulva is marked by an increase in androgen and a decrease inoestrogen and progesterone receptors. This distribution of receptors would indicate a limited role foroestrogen creams on the vulva. 相似文献
7.
Matthias Kirsch Patrick Weigel Thomas Pinzer Rona S Carroll Peter McL Black Hans-Konrad Schackert Gabriele Schackert 《Clinical cancer research》2005,11(3):1259-1267
PURPOSE: Cerebral metastases represent the most common type of brain tumors. This study investigated the effects of endogenous endostatin on hematogenous cerebral melanoma metastases. EXPERIMENTAL DESIGN: Murine K1735 melanoma cells were transfected with the mouse endostatin cDNA. Experimental tumors were induced either by s.c. injection, intracerebral implantation, or via injection into the internal carotid artery to simulate hematogenous metastatic spread. The effects of endostatin expression on tumor incidence, growth pattern, and vascularity were analyzed. RESULTS: In vitro secretion of endostatin by 2.5 x 10(5) cells within 24 hours was 0.12 +/- 0.03 ng, 4.35 +/- 0.4, and 1.18 +/- 0.7 ng/mL for wild type and two endostatin-transfected K1735 clones termed K1735-endo/2 and K1735-endo/8, respectively. Tumor inhibition in vivo correlated with endogenous endostatin production. Within 25 days, growth of s.c. K1735-endo/2 tumors was <20% compared with wild-type controls. Following intracerebral implantation the average survival time of mice was 27.8 +/- 2.6 versus 13.3 +/- 3.7 days in the K1735-endo/2 versus the wild-type group, respectively. Intracarotid injection of 1 x 10(5) wild-type cells killed the mice within 24 +/- 1.8 days. In contrast, endostatin expression prevented macroscopic metastatic tumor growth in 11 of 12 mice, although viable microscopic tumor pockets were detectable in all animals. CONCLUSION: Endostatin inhibits tumor progression of multiple cerebral metastases in vivo. Hematogenous micrometastases are more efficiently suppressed than tumors resulting from high focal cell numbers which may be due to a higher angiogenic signaling exerted by massive cell deposits. Endostatin may prevent solid tumor growth more effectively by inhibition of early angiogenesis. 相似文献
8.
Visit to the pediatrician: Children''s concerns 总被引:1,自引:0,他引:1
9.
10.
Evidence-based guidelines and subsequent studies support the effectiveness of counselling and pharmacotherapy as first-line smoking cessation interventions. Gender is one of many factors that may have an impact on the efficacy of smoking cessation interventions. There is only very limited evidence, however, to answer the question of how gender influences the effectiveness of smoking cessation interventions. Research does suggest that concern about weight gain is related to women's confidence in their ability to stop smoking and this should be kept in mind when designing interventions. In the meantime, any client who indicates a desire to stop smoking should be offered one of the smoking cessation interventions that are already available. 相似文献