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排序方式: 共有465条查询结果,搜索用时 942 毫秒
111.
Kofoed KF Carstensen S Hove JD Freiberg J Bangsgaard R Holm S Rabøl A Hesse B Arendrup H Kelbaek H 《European journal of nuclear medicine and molecular imaging》2002,29(8):991-998
We tested the hypothesis that low whole-body insulin sensitivity in patients with ischaemic heart disease and impaired left ventricular (LV) function is associated with abnormalities of insulin-mediated myocardial glucose uptake affecting outcome after coronary bypass surgery (CABG). We studied 29 patients with ischaemic heart disease and impaired LV ejection fraction (EF) and age-matched healthy volunteers ( n = 30). As assessed by euglycaemic glucose-insulin clamp, 15 patients had a low and 14 a normal whole-body insulin sensitivity. Using positron emission tomography, patterns of fluorine-18 fluorodeoxyglucose and nitrogen-13 ammonia uptake in addition to quantified glucose uptake, blood flow and hyperaemic blood flow were assessed before CABG in 16 myocardial segments of the left ventricle. Major adverse cardiac events and LVEF were evaluated 7 months after CABG. Glucose uptake in normokinetic PET-normal myocardium was found to be higher in patients with normal whole-body insulin sensitivity ( P < 0.001), whereas in patients with low whole-body insulin sensitivity more segments displayed a pattern of reduced glucose uptake in normoperfused myocardium (PET-reverse mismatch) ( P < 0.05). Hyperaemic blood flow was impaired in both patient groups. A major cardiac event after CABG could partly be predicted by the LV extent of normoperfused segments with PET-reverse mismatch. We conclude that low whole-body insulin sensitivity in patients with ischaemic heart disease and impaired LV function is associated with impaired insulin-mediated myocardial glucose uptake, which is partially predictive of a worse outcome after CABG. 相似文献
112.
This study determined the accuracy of standard radiographs in observing radiolucency adjacent to the tibial component in total knee arthroplasty. A model of the proximal tibia was used. Plastic sleeves of different heights were glued under the tibial tray to imitate radiolucency. By tilting the x-ray tube 1degrees at a time, an investigation was performed to determine how many degrees it would take to cover the heights of the different plastic sleeves. In a clinical study of patients at standard follow-up, 21 knees were examined using standard radiographs. Radiographs using image intensification were then taken of the same knees to obtain radiographs with views parallel to the plane of the tibial tray. The results of the study on the phantom showed that a 1degrees deviation of the x-ray beam from the optimal position would obscure a 0.5-mm "radiolucency." This was true for radiolucencies of 2, 3, 4, and 5 mm. This was confirmed in the clinical study where < or = 4 mm of radiolucency was obscured on standard radiographs. Therefore, standard radiographs cannot be used to determine radiolucency. The 2-mm radiolucency normally associated with loosening is not clinically valid. 相似文献
113.
Treatment of uncomplicated malaria in children in Guinea-Bissau with chloroquine,quinine, and sulfadoxine-pyrimethamine 总被引:1,自引:0,他引:1
Kofoed PE Có F Johansson P Dias F Cabral C Hedegaard K Aaby P Rombo L 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2002,96(3):304-309
With the increasing resistance to commonly used antimalarial drugs, different untested 'local' treatment regimens for malaria will arise. We compared commonly used treatment regimens for children in Guinea-Bissau. Symptomatic children with Plasmodium falciparum mono-infection were allocated at random to one of 4 treatments: 15 mg/kg quinine twice a day for 3 d (group 1); 10 mg/kg quinine twice a day for 3 d followed by a total dose of 25 mg chloroquine base given over 3 d (group 2); a total dose of 50 mg/kg chloroquine base given in 2 daily doses for 3 d (group 3), or sulfadoxine-pyrimethamine (group 4). On day 28 more children from group 1 (33%; relative risk [RR] = 2.9, 95% confidence interval [CI] 1.5-5.7) and group 2 (26%; RR = 2.1, CI 1.0-4.3) had had parasitaemia than in group 4 (12%), whereas no significant difference was found between group 3 (17%; RR = 1.3, CI 0.6-2.2) and group 4. No severe adverse reaction was observed in any of the groups. Chloroquine is still effective in Guinea-Bissau at an increased dose of 50 mg/kg, which appears safe when given orally in 2 daily doses for 3 d. Sulfadoxine-pyrimethamine could serve as an efficient, cheap and easy to administer second-line drug, leaving quinine to be used for third-line treatment. Quinine should not be used in short courses, nor does the combination of quinine and chloroquine have any advantage. 相似文献
114.
Abstract: A preterm infant developed bilateral tension pneumothoraces and extensive vascular air embolism 6 h after being commenced on nasal continuous positive airway pressure (CPAP). Neonatal clinicians should be aware that catastrophic vascular air embolism could occur in infants receiving nasal CPAP, a modality of respiratory support conventionally considered non-invasive and 'safe'. 相似文献
115.
C M?lgaard BL Thomsen A Prentice TJ Cole KF Michaelsen 《Archives of disease in childhood》1997,76(1):9-15
Data from healthy children are needed to evaluate bone mineralisation during childhood. Whole body bone mineral content (BMC) and bone area were examined by dual energy x ray absorptiometry (Hologic 1000/W) in healthy girls (n = 201) and boys (n = 142) aged 5-19 years. Centile curves for bone area for age, BMC for age, bone area for height, and BMC for bone area were constructed using the LMS method. Bone mineral density calculated as BMC/bone area is not useful in children as it is significantly influenced by bone size. Instead, it is proposed that bone mineralisation is assessed in three steps: height for age, bone area for height, and BMC for bone area. These three steps correspond to three different causes of reduced bone mass: short bones, narrow bones, and light bones. 相似文献
116.
117.
Activation of telomerase seems to be a prerequisite for immortalization and is found in permanent cell lines and most malignant tumors. Normal somatic cells are generally telomerase negative, except for bone marrow stem cells. Weak activity is also present in peripheral blood cells. In the present study strong telomerase activity was demonstrated in vivo in normal mature cells of the immune system, as well as in malignant lymphomas. Benign lymph nodes had lower telomerase activity than benign tonsils, which exhibited intermediate to high activity comparable with findings in malignant lymphomas. In benign tonsils the activity seemed to be restricted to germinal center B cells. In benign lymphoid tissues telomerase activity correlated with B-cell numbers and cell proliferation, but this was not observed in the lymphoma group. High- grade lymphomas exhibited higher levels of telomerase compared with low- grade cases. The data showed that in vivo activation of telomerase is a characteristic feature of germinal center B cells. Different signals for activation of telomerase are likely to exist, one of them being immune stimulation. The data suggest that telomerase activity in malignant lymphomas can be explained by an "induction and retention" model, ie, transformation occurs in a normal, mature B cell with reactivated telomerase, which is retained in the neoplastic clone. 相似文献
118.
Montgomery Rice V; Limback SD; Roby KF; Terranova PF 《Human reproduction (Oxford, England)》1998,13(5):1285-1291
This study determined effects of follicle stimulating hormone (FSH) alone
and in combination with tumour necrosis factor (TNF), on granulosa cells
from small (5-10 mm diameter) and large (>10-25 mm) follicles during
follicular and luteal phases of the cycle and during periods of acyclicity.
Granulosa cells were collected from ovaries of premenopausal women
undergoing oophorectomy. The cells were cultured with human FSH (2 ng/ml)
and testosterone (1 microM) in the presence or absence of human TNF-alpha
(20 ng/ml). Media were removed at 48 and 96 h after culture and
progesterone, oestradiol and cAMP in media were measured by
radioimmunoassays. FSH stimulated the accumulation of oestradiol from
granulosa cells of small follicles during the follicular and luteal phases
but not during acyclicity; and TNF reduced oestradiol accumulation in the
presence of FSH. Interestingly, in granulosa cells from small follicles,
progesterone and cAMP secretion increased in response to FSH and neither
was affected by TNF. Thus, TNF specifically inhibited the conversion of
testosterone to oestradiol in granulosa cells from small follicles. FSH
stimulated oestradiol production by granulosa cells of large follicles
obtained only during the follicular phase of the cycle and TNF inhibited
the FSH-induced oestradiol secretion. Granulosa cells obtained from large
follicles during the luteal phase and during acyclicity did not accumulate
oestradiol in response to FSH. However, FSH increased progesterone and cAMP
secretion by granulosa cells obtained from large follicles during the
follicular and luteal phases. During the luteal phase alone, TNF in
combination with FSH increased progesterone accumulation above that of FSH
alone. FSH did not increase progesterone, oestradiol or cAMP secretion by
granulosa cells obtained from large follicles during acyclicity. Thus, FSH
increases progesterone, oestradiol and cAMP secretion by granulosa cells of
small follicles during the follicular and luteal phases and TNF appears to
inhibit FSH-induced oestradiol secretion specifically in those cells. In
large follicles, FSH- stimulated granulosa cell secretion of oestradiol is
limited to the follicular phase and this effect can be inhibited by TNF. In
addition, when granulosa cells of large follicles do not increase
oestradiol secretion in response to FSH, TNF stimulates progesterone
secretion.
相似文献
119.
The L3-4 supraspinous and interspinous ligaments in 10 goats were replaced with carbon fibers stabilized with silk-suture seizing. The implants were removed after 3 weeks in 5 animals and after 3 months in the other 5. The maximum traction strength of nonimplanted slings was 157 +/- 9 kg (M +/- SD). After implantation, the strength was reduced to 136 +/- 17 kg, and after 3 months to 107 +/- 9 kg. However, the maximum strength of the spinous processes was 71 +/- 19 kg, which was less than the strength of 3-month implants. We concluded that the carbon fiber sling stabilized with silk sutures could be used for replacement of the interspinous ligament. 相似文献
120.
Jette Ammentorp Anne Mette Rasmussen Betty N?rgaard Edel Kirketerp Poul-Erik Kofoed 《International journal for quality in health care》2007,19(2):120-124
BACKGROUND: Using paper questionnaires to measure quality of care from the perspective of the patient is a time consuming procedure resulting in very slow feedback. Response rates are low and patients who cannot read the local language are usually excluded. OBJECTIVE: To investigate the applicability of an electronic questionnaire by evaluating the response rate. To study whether computer-based continuous monitoring could elucidate reasons for parents being less satisfied with care and treatment and to compare parent satisfaction with the results of a study performed in 2003. METHODS: Parents were asked to assess the quality of care and treatment by answering questions on a touch-screen computer. The questions, which were translated into seven languages, corresponded to the indicators selected by the department for monitoring parents' satisfaction. The system was developed in cooperation with a software company. RESULTS: A total of 780 parents answered (69%). Of these, 2% parents answered in a foreign language. The main reasons for being less satisfied were perceived difficulties in getting in contact with the staff, having experienced unnecessary long waiting time and having the impression that the nurses did not have enough time. Significant improvements in satisfaction had occurred as compared to a study from 2003. CONCLUSION: By using electronic questionnaires, it was possible to focus on the small percentage of parents not satisfied, to identify reasons for being less satisfied and to respond immediately to the feedback from the parents. Electronic surveys produce a satisfactory response rates. 相似文献