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81.
OBJECTIVE: To investigate the expression of inducible nitric oxide synthase (iNOS) in oropharyngeal and hypopharyngeal squamous cell carcinoma (SCC) and its relation to p53 expression, histologic differentiation, clinical data, and prognosis. STUDY DESIGN: A retrospective survey. METHODS: Primary tumors for analyses were obtained from 118 patients diagnosed with SCC of the oropharynx or hypopharynx between 1975 and 1998 in eastern Finland. Immunohistochemical analysis was used to evaluate the expression of iNOS and p53. The expression pattern of iNOS was related to p53 expression, clinical data, and survival. RESULTS: High iNOS score was associated significantly with high nuclear p53 expression index (P = .006) and positive cytoplasmic p53 expression (P = .025). The score for iNOS expression was significantly lower in the largest (T4) tumors (P = .043). No association was seen between iNOS score and N or M class, tumor stage, or histologic differentiation. The score for iNOS expression was not related to overall survival. CONCLUSIONS: The expressions of iNOS and p53 seem to be inter-related in pharyngeal SCC, although the causality remains to be clarified. The expression of iNOS shows no prognostic value in pharyngeal SCC.  相似文献   
82.
We report an illustrative case of presurgical evaluation for epilepsy surgery, where the three-dimensional reconstructed magnetic resonance imaging played a pivotal role in determining the exact location of the subdural strip electrodes in temporomesial area. The tip of one the frontal strip electrodes was actually recording the temporopolar ictal activity. This contributed conclusively to the decision for surgical treatment and to the excellent outcome.  相似文献   
83.
Eleven-year trends of stroke in Turku,Finland   总被引:1,自引:0,他引:1  
The Turku Stroke Register included stroke events at all ages during the years 1982-1992. The incidence of stroke declined in all age groups, even in the oldest one. An even steeper decline was observed in mortality from stroke. Ischemic strokes contributed most to the observed decline, while subarachnoid and intracerebral hemorrhage showed mainly flat trends. Flat trends were also observed for recurrent strokes. The absolute number of strokes remained stable through the study years, but the population above 75 years of age doubled. More than half of the strokes occurred in people aged 75 years or older, and three fourths of them occurred in women. The incidence and mortality rate of ischemic stroke declined steeply in all age groups. Due to an increase in elderly people in the background population, the total number of strokes remained stable. Thus, in spite of the observed declining trends in incidence, the need for stroke care has not diminished.  相似文献   
84.
OBJECTIVE: To assess the influence of central and peripheral neurological diseases on the incidence of accidental falls of the aged. DESIGN: 1. Case-control study with cross-section at two years and 2. prospective study in a follow-up up to seven years thereafter. SETTING: Sample of a population study including all 589 inhabitants older than 70 years in three rural communities. PARTICIPANTS: 44 subjects with recurrent falls during two years' follow-up and 41 age and sex matched controls. MEASURES: Neurological diseases and evaluation, other diseases, and incidence of falls during the seven years' follow-up after the cross-section. RESULTS: Compared with the controls the fallers had more often multiple vascular lesions of the brain, extrapyramidal symptoms and signs as well as lumbar nerve root lesions. In the follow-up, cerebrovascular disease, especially with multiple lesions and residual signs of pyramidal tract lesion, Parkinson's disease, rigidity and hypokinesia were associated with increases risk of falling. In multivariate analysis signs of pyramidal tract lesion, rigidity and prior falls were predictors of falls. An increase in the incidence of falls was also associated with vascular lesion of the cerebellum, cerebral white matter hypodensity and cortical atrophy visible on CT. CONCLUSIONS: High incidence of falls was associated with chronic central nervous system diseases. Lumbar root lesions were more common among the fallers but did not increase the incidence of falls in the follow-up.Neurological diseases and evaluation, other diseases, and incidence of falls during the seven years' follow-up after the cross-section.Compared with the controls the fallers had more often multiple vascular lesions of the brain, extrapyramidal symptoms and signs as well as lumbar nerve root lesions. In the follow-up, cerebrovascular disease, especially with multiple lesions and residual signs of pyramidal tract lesion, Parkinson's disease, rigidity and hypokinesia were associated with increased risk of falling. In multivariate analysis signs of pyramidal tract lesion, rigidity, and prior falls were predictors of falls. An increase in the incidence of falls was also associated with vascular lesion of the cerebellum, cerebral white matter hypodensity and cortical atrophy visible on CT.  相似文献   
85.
Summary The long-term hearing results are presented for 135 ears operated on radically. In 59 of the ears temporary paraffin filling of the tympanic cavity was employed after the removal of the typanic mucosa at operation. The filling material was removed, and the ossiculoplasty was performed about 6 months later. In 76 ears a one-stage operation with tympanoplasty and Silastic sheeting was employed.There were no statistical differences between the groups of ears mentioned according to hearing results early (1 year) or late (5–14 years) postoperatively or in the deterioration of the air-bone gaps after the first postoperative year (P>0.05). The late change in the air-bone gap was significant in both groups (paraffin group: 6.1 dB; Silastic sheeting group: 5.7 dB; P<0.05). The total improvement of hearing late after surgery (as compared to the preoperative hearing) was significantly better in the paraffin group than in ears with Silastic sheeting (P<0.05). Paraffinplasty seems to be a suitable way to avoid tympanic adhesions.  相似文献   
86.
Positron emission tomography (PET) enables quantitative measurements of myocardial blood flow (MBF) and myocardial flow reserve (MFR). Recent developments and improved availability of PET technology have resulted in growing interest in translation of quantitative flow analysis from mainly a research tool to routine clinical practice. Quantitative PET measurements of absolute MBF and MFR have potential to improve accuracy of myocardial perfusion imaging in diagnosis of multivessel coronary artery disease as well as definition of the extent and functional importance of stenoses. This article reviews recent advances and experience in the quantitative myocardial perfusion imaging together with issues that need to be resolved for quantitative analysis to become clinical reality.  相似文献   
87.

Purpose

Nuclear cardiology is widely used to diagnose coronary artery disease and to guide patient management, but data on current practices, radiation dose-related best practices, and radiation doses are scarce. To address these issues, the IAEA conducted a worldwide study of nuclear cardiology practice. We present the European subanalysis.

Methods

In March 2013, the IAEA invited laboratories across the world to document all SPECT and PET studies performed in one week. The data included age, gender, weight, radiopharmaceuticals, injected activities, camera type, positioning, hardware and software. Radiation effective dose was calculated for each patient. A quality score was defined for each laboratory as the number followed of eight predefined best practices with a bearing on radiation exposure (range of quality score 0 – 8). The participating European countries were assigned to regions (North, East, South, and West). Comparisons were performed between the four European regions and between Europe and the rest-of-the-world (RoW).

Results

Data on 2,381 European patients undergoing nuclear cardiology procedures in 102 laboratories in 27 countries were collected. A cardiac SPECT study was performed in 97.9 % of the patients, and a PET study in 2.1 %. The average effective dose of SPECT was 8.0?±?3.4 mSv (RoW 11.4?±?4.3 mSv; P?<?0.001) and of PET was 2.6?±?1.5 mSv (RoW 3.8?±?2.5 mSv; P?<?0.001). The mean effective doses of SPECT and PET differed between European regions (P?<?0.001 and P?=?0.002, respectively). The mean quality score was 6.2?±?1.2, which was higher than the RoW score (5.0?±?1.1; P?<?0.001). Adherence to best practices did not differ significantly among the European regions (range 6 to 6.4; P?=?0.73). Of the best practices, stress-only imaging and weight-adjusted dosing were the least commonly used.

Conclusion

In Europe, the mean effective dose from nuclear cardiology is lower and the average quality score is higher than in the RoW. There is regional variation in effective dose in relation to the best practice quality score. A possible reason for the differences between Europe and the RoW could be the safety culture fostered by actions under the Euratom directives and the implementation of diagnostic reference levels. Stress-only imaging and weight-adjusted activity might be targets for optimization of European nuclear cardiology practice.
  相似文献   
88.
The glucose analog (18)F-FDG is commonly used to quantify regional glucose uptake in vivo. The aim of this study was to test whether the analysis of plasma (18)F-FDG kinetics could be used to estimate endogenous glucose production (EGP) and the total rate of appearance (Ra), total rate of disappearance (Rd), and the metabolic clearance rate (MCR) of glucose. METHODS: Fourteen pigs were coinjected with (18)F-FDG and 6,6-(2)H-glucose ((2)H-G) during fasting (n = 6) and during physiologic (1.0 mU.kg(-1).min(-1), n = 4) and supraphysiologic (5.0 mU.kg(-1).min(-1), n = 4) euglycemic hyperinsulinemia. Arterial plasma was sampled for 180 min to quantify the parameters for the 2 tracers. RESULTS: Fasting Rd((2))(H-G) and Rd(FDG) were 12.3 +/- 2.1 and 13.3 +/- 1.3 micromol.kg(-1).min(-1) (difference not statistically significant [NS]). M values were more than doubled between the 2 clamp studies (P < 0.0001). Rd((2))(H-G) and Rd(FDG) were dose-dependently higher during the hyperinsulinemic state (19.8 +/- 3.7 vs. 18.9 +/- 1.1 and 31.4 +/- 4.1 vs. 31.9 +/- 2.3 in 1.0 and 5.0 mU.kg(-1).min(-1) studies, respectively; difference between tracers NS) than during the fasting state, with a parallel suppression of EGP((2))(H-G) and EGP(FDG). Parameters estimated by (18)F-FDG and (2)H-G were equivalent in all groups; their agreement was confirmed by Bland-Altman examination. Total Rd(FDG) correlated with Rd((2))(H-G) (r = 0.74; P = 0.003), M (r = 0.92; P = 0.001), MCR((2))(H-G) (r = 0.52; P = 0.037), and EGP((2))(H-G) (r = -0.71; P = 0.004). EGP(FDG) correlated with EGP((2))(H-G) (r = 0.62; P = 0.018), Rd((2))(H-G) (r = -0.78; P = 0.001), and MCR((2))(H-G) (r = -0.67; P = 0.008). The (18)F-FDG mean transit time correlated inversely with the M and Rd values and positively with EGP. CONCLUSION: The glucose analog (18)F-FDG can be used in the simultaneous estimation of whole-body glucose turnover and production and regional (18)F-FDG PET measurements under both fasting and insulin-stimulated conditions.  相似文献   
89.
A rapid, sensitive and selective method using LC-MS/MS was developed and validated for the simultaneous quantitative determination of five polyamines N(1),N(12)-diethylspermine (DESpm), N-ethylspermine (EtSpm), N(1)-ethylspermidine (EtSpd), spermidine (Spd) and N(1)-ethyl-1,3-diaminopropane (EtDAP) without any derivatization steps. The LC-MS/MS system was operated using the positive electrospray ionization (ESI) mode. The chromatographic separation only took 10min and was performed on a reversed phase C18 column with 0.1% heptafluorobutyric acid as the ion-pairing agent and acetonitrile gradient. Stable, deuterium labelled internal reference compounds of the five analytes were included in the quantification. The lower limit of quantification for all of the five analytes was 0.03muM and the method was linear for DESpm, EtSpd, Spd and EtDAP over the range of 0.03-60muM and for EtSpm over the range of 0.03-30muM. Correlation coefficients (R(2)) were always >0.995 for all the analytes. The precision of the overall method ranged from 0.2 to 9.7% as intra-day variability and from 0.9 to 6.8% as inter-day variability. The intra-day and inter-day accuracy of the assay ranged between 87.6-109.8% and 89.6-106.6%, respectively. The method has been applied successfully to quantify metabolites of DESpm as a substrate for recombinant human polyamine oxidase.  相似文献   
90.
Objective To investigate the characteristics, local agreements and changes regarding repeat prescribing processes in primary health care in Finland. Setting Twenty‐eight municipal health centres nationwide. Method Twenty‐eight physicians and 28 medical receptionists were given semi‐structured telephone interviews about repeat prescribing practices. The repeat prescribing process of each health centre was displayed as a flow chart and the processes were classified according to the quality of the practical flow and the medication review. Key findings There are various ways of carrying out repeat prescribing in different health centres. In some centres, a review of the medications is recognised as part of the repeat prescribing process, but in others there is no systematic review of the patients' medication. Repeat prescribing is often performed in a busy atmosphere. Repeat prescribing systems have evolved over time without proper management, and few local guidelines exist. Conclusions There is a need to reorganise the repeat prescribing systems in primary health care. A regular review of long‐term medications, in particular, needs to become a part of the repeat prescribing process. There is a need for both local and national guidelines.  相似文献   
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