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51.
BACKGROUND AND PURPOSE: In MR spectroscopic imaging (MRSI), the volume-selection profiles of metabolites differ from each other. These differences cause variations in metabolite intensities, which are particularly prominent when the hippocampi are evaluated. We hypothesize that the errors arising from these effects cause notable artifact when temporal lobe epilepsy (TLE) is lateralized with MRSI. METHODS: We examined a metabolite phantom, control subjects, and patients with TLE by using MRSI. We calculated the error arising from the different volume-selection profiles of metabolites in vitro and evaluated this correction in the examination of the control subjects and in the lateralization of epilepsy in the patients. RESULTS: Without a correction, a considerable error in the metabolite content existed, even deep inside the spectroscopic volume of interest. The result was false asymmetry (P < .008) in the hippocampi of control subjects. Among the 11 patients, TLE was correctly lateralized in three only after the correction was made, and in one, TLE was incorrectly lateralized. CONCLUSION: The volume-selection profiles of N-acetylaspartate, choline, and creatine differ enough to cause a significant error, even in the metabolite ratios, when patients with TLE are examined with MRSI. We propose a simple phantom method to correct for this error without a need to modify the pulse sequence.  相似文献   
52.
PURPOSE: This study examined the relative contribution of genetic and environmental effects on maximal leg extensor power and also investigated whether leg extensor power and maximum voluntary isometric knee extensor strength share a genetic component. METHODS: Muscle functions were measured as part of the Finnish Twin Study on Aging in 101 monozygotic (MZ) and 116 dizygotic (DZ) female twin pairs aged 63-76 yr. Leg extensor power was measured using the Nottingham Leg Extensor Power Rig and maximum voluntary isometric knee extensor strength using an adjustable dynamometer chair. The analyses were carried out using the maximum likelihood method in Mx-program on the raw data set. RESULTS: A bivariate Cholesky decomposition model showed that leg extensor power and isometric knee extensor strength shared a genetic component in common, which accounted for 32% of the total variance in leg extensor power and 48% in isometric knee extensor strength. In addition, power and strength had a nonshared environmental effect in common accounting for four percent of the variance in power and 52% in strength. Remaining variance for leg extensor power was due to trait-specific shared and nonshared environmental effects. CONCLUSION: Observed genetic effect in common for leg extensor power and maximum voluntary isometric knee extensor strength indicated that these two traits are regulated by the same genes. However, also environmental effects have a significant role in explaining the variability in power and strength.  相似文献   
53.
This article summarizes the current status of 1H MRS in detecting and quantifying a boron neutron capture therapy (BNCT) boron carrier, L-p-boronophenylalanine-fructose (BPA-F) in vivo in the Finnish BNCT project. The applicability of 1H MRS to detect BPA-F is evaluated and discussed in a typical situation with a blood containing resection cavity within the gross tumour volume (GTV). 1H MRS is not an ideal method to study BPA concentration in GTV with blood in recent resection cavity. For an optimal identification of BPA signals in the in vivo 1H MR spectrum, both pre- and post-infusion 1H MRS should be performed. The post-infusion spectroscopy studies should be scheduled either prior to or, less optimally, immediately after the BNCT. The pre-BNCT MRS is necessary in order to utilise the MRS results in the actual dose planning.  相似文献   
54.
OBJECTIVE: The purpose of this study was to evaluate the significance of diabetes mellitus as a risk factor for postoperative major morbidity and mortality after surgery for critical lower limb ischemia (CLI). SUBJECTS: A national vascular registry (Finnvasc)-based survey included 5709 operations for CLI from 1991 through 1999. Of these operations, 2508 (44%) were performed on diabetics. Tissue loss was the indication for surgery in 77% of diabetics and in 52% of nondiabetics. The proportion of femorodistal bypasses was 43% in diabetics and 24% in nondiabetics, whereas the proportion of reconstructions for aortofemoral arterial occlusive disease was 16% in diabetics and 34% in nondiabetics. RESULTS: Thirty-day mortality was 4.5% in diabetics and 3.4% in nondiabetics ( P = .05). The rate for early below-knee amputation was 6.5% in diabetics and 3.3% in nondiabetics ( P < .001). Independent factors for postoperative death were aortofemoral reconstruction (odds ratio [OR], 4.0), preoperative cardiac risk factor (OR, 3.1), primary surgery (OR, 2.0), renal insufficiency (OR, 1.9), urgent surgery (OR, 1.7), and age (OR, 1.3). Diabetes was an independent risk factor for postoperative below-knee amputation (OR, 1.7), cardiac complications (OR, 1.5), and superficial wound infection (OR, 1.3). There was an inverse association between diabetes and acute graft occlusion (OR, 0.8). Independent risk factors for early postoperative mortality in diabetes were aortofemoral reconstruction (OR, 2.5), urgent surgery (OR, 2.0), male gender (OR, 2.0), renal insufficiency (OR, 1.9), cardiac risk factor (OR, 1.7), and age (OR, 1.4). In nondiabetics independent risk factors for early postoperative mortality were aortofemoral reconstruction (OR, 4.5), cardiac risk factor (OR, 3.6), primary surgery (OR, 2.6), and extra-anatomic bypass (OR, 2.3). CONCLUSIONS: Diabetes was not an independent risk factor for early postoperative mortality in CLI as there was an increased morbidity in diabetics associated with old age, male gender, known coronary artery disease, and renal insufficiency, as well as urgent surgery. As diabetics have increased proclivity for these factors, special attention needs to be paid to their preoperative assessments.  相似文献   
55.
We investigated differences in life events and social support between subgroups of depressed patients and the distribution of life events in phases preceding or during depression. In the Vantaa Depression Study, 269 psychiatric patients with DSM-IV major depressive disorder were diagnosed with Schedule for Clinical Assessment in Neuropsychiatry, Version 2.0, and Structured Clinical Interview for DSM-III-R personality disorders (SCID-II). Life events during the 12 months preceding the interview were investigated with the Interview for Recent Life Events, and social support with the Interview Measure of Social Relationships and the Perceived Social Support Scale-Revised. Nearly all patients (91%) reported life events, on average 4.1 per preceding year. No major differences between sociodemographic or clinical subgroups were found; the frequency of events was somewhat greater among the younger subjects, whereas those with comorbid alcoholism or personality disorders perceived less social support. Although events were distributed evenly between the time preceding depression, the prodromal phase, and the index major depressive episode, two thirds of the patients attributed their depression to some event. Despite clinical and sociodemographic heterogeneity, patients with major depressive disorder are fairly homogeneous in terms of life events during the preceding year. Events do not cluster in any particular phase of the progression to an episode.  相似文献   
56.
The definition of envy is based on views of anthropology, sociology, psychology and nursing science. According to these definitions, a nurse education community consists of shared values, customs and beliefs common in the nursing community. The purpose of this paper was to describe envy in the reciprocal relations between student nurses in a polytechnic of health and welfare in Finland. The sample consisted of 110 student nurses in one faculty of health and welfare in a Finnish polytechnic. They were selected from among the available (attending classes) students, who had been studying in the same group for 1-3 years in 1996. The response percentage was 85.5 (n=94). The data were processed by various statistical methods. The findings of envy in a nurse education community were defined through the student nurses' views of their sense of self, their relations with their fellow students, the objects of envy and also the influence of the lecturers. The ways of coping with envy were also identified. The most common object of envy was a fellow student who worked part-time while studying. Another object of envy consisted of fellow students successful in examinations and skills, such as listening, friendships and good ideas. The students coped with their envy by sharing their own success and by denying envy. These results highlight some essential points of envy in a nurse education community and underline the need for open discussion, as emotions and envy are important to understand as part of nurse education. If envy is not identified, it may cause learning problems and even problems in patient care.  相似文献   
57.
OBJECTIVE: To ascertain the personal networks GPs use when managing children with psychiatric problems. DESIGN: Cross-sectional postal study. SETTING: Health centres in the catchment area of Tampere University Hospital, Finland. SUBJECTS: GPs (n = 755) were sent a postal questionnaire. The response rate was 66.1%. MAIN OUTCOME MEASURES: A fill-in picture was used to identify professionals within the network of each GP. The quality of collaboration between GPs and professionals in health centres, other municipal authorities and secondary health care was assessed on a four-step Likert scale. RESULTS: A majority of respondents (64%) could name at least one person from their health centre with whom they cooperate in child psychiatric cases. The corresponding number in contact with other municipal authorities was 40%, and 25% with secondary care level. Almost all GPs (95%) had mostly positive experiences of cooperation with different professionals in the health centres, 73% with other municipal authorities and 47% with child psychiatric specialist care. CONCLUSION: The personal networks of health centre doctors call for improvement if the increasing child psychiatric problems are to be kept under control. This is a challenge for both primary and secondary care level doctors.  相似文献   
58.
All hip fracture patients (age <50 years, pathological and subtrochanteric fractures excluded) were registered at admission to hospital and at 4 months (mortality up to 1 year) between 1989 and 1997 in Peterborough District Hospital (2083 patients) and Oulu University Hospital (1702 patients). The mean age at fracture was 80.3 years in Peterborough and 78.3 years in Oulu. Respectively, 69% and 62% of the patients had been living in their own homes, 50% and 54% had been able to walk alone unassisted. In Oulu, the patients were discharged after a mean stay of 7.1 days, most of them to health care centre hospitals (71%) and only 21% to their original place of residence. In Peterborough 81% were discharged to their original place of residence after a mean stay of 15.6 days. At 4 months, 54% were living at their own homes in Peterborough and 44% in Oulu. The overall mortality at 1 year was 27.1% in Peterborough and 24.9% in Oulu.  相似文献   
59.
Purpose. We studied which, age of the patient or density of the breast accounts for the sensitivity of mammography and ultrasonography (US). Furthermore we studied whether the overall impression on the density of the breast or the density in tumour area accounts for the sensitivity of mammography and ultrasonography. Materials and methods. The material consisted of 572 consecutive histologically and 5 cytologically verified breast cancer cases. Mammography and US examinations were performed immediately before breast cancer operations and information on the findings were received from the original patient files and classified as malignant or benign. The density of breast parenchyma to fatty, mixed or dense in total breast and separately in tumour area was defined by a radiologist group from the original mammograms by comparing to model mammograms. The sensitivity (Se) of mammography and US was compared in 3 age groups (26–49, 50–59 and 60–92) and in the different density classes. Results. Sensitivity of mammography increased by age (density-adjusted OR=0.2, 95%, CI 0.1–0.5) in age group 26–49 compared to age group 60–92) and with fattiness of the breast (age-adjusted OR=0.4, 95%, CI 0.1–1.0 for dense breast parenchyma in tumour area compared to fatty breast). Sensitivity of US was inversely related to age (density-adjusted OR=2.3, 95%, CI 1.0–5.2 in age group 26–49 compared to age group 60–92) and directly related with fattiness of breast (age-adjusted OR=0.5, 95%, CI 0.2–0.9 by dense breast parenchyma in tumour area compared to fatty breast). Density in the tumour area compared to total breast density was related only mariginally better sensitivity both of mammography (0.4 vs. 0.6) and of US (0.5 vs. 0.6). itConclusion. Sensitivity of both mammography and sensitivity of US are independently related both to the age of the patient and to the density of the breast. The effect of age is inverse and that of density parallel between mammography and US on sensitivity. The effect of overall breast density was close to the effect of density at the site of the tumour on the sensitivity of both mammography and US.  相似文献   
60.
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