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排序方式: 共有96条查询结果,搜索用时 31 毫秒
1.
Nakada  T; Kwee  IL; Griffey  BV; Griffey  RH 《Radiology》1988,168(3):823-825
Noninvasive metabolic magnetic resonance (MR) imaging reflecting glucose metabolism in the aldose-reductase-sorbitol (ARS) pathway was performed in the rabbit head; after administration of the fluorinated glucose analogue 3-fluoro-3-deoxy-D-glucose (3FD-glucose), fluorine-19 images were generated. Images of 3FD-glucose showed significant 3FD-glucose uptake by adipose tissue, indicating its buffering effects in case of excess loads of glucose. Images of 3-fluoro-3-deoxy-D-sorbitol (3FD-sorbitol) demonstrated the spatial distribution of aldose reductase activities and significant sorbitol accumulation in the lens. Images of 3-fluoro-3-deoxy-D-fructose (3FD-fructose) showed preferential uptake of fructose by muscle tissue. The extremely low toxicity of 3FD-glucose indicates promise for its clinical application in metabolic imaging.  相似文献   
2.
AimsTo investigate the seasonal variations of HbA1c values in a semi-arid climate among type 2 diabetic patients throughout 11 years of care.MethodsA retrospective cohort study of 2860 patients with 61,187 HbA1c measures. We calculated the averages of HbA1c values of all patients and sub-groups defined by age, gender, BMI, ethnicity, insulin use, smoking status and region of residence, matched to the mean temperature and diurnal range over the 30 and 60 days prior to the HbA1c test date.ResultsWe found a sinusoidal seasonal pattern with statistically significant HbA1c levels gaps between the spring peak and the autumn trough (F = 18.4, P < 0.001). The lowest values were in October-November and the highest in March or August with a difference of 0.17–0.31% (2–4 mmol/mol). We found different relations between the mean temperature and HbA1c depending on season, gender, age, ethnicity and smoking habits.ConclusionThe study identified specific subgroups in which the seasonal influence is particularly marked. A possible explanation is that during hot periods people tend to change their diet and decrease their physical activity, effecting indirectly diabetic imbalance. Recognition of the seasonal variations of HbA1c levels in this geographical region could help physicians with diabetes care and HbA1c control.  相似文献   
3.
BACKGROUND: Psychosocial variables such as major stressful life events/daily stressful events have been associated with health care utilization. OBJECTIVE: Our aim was to examine the effects of a guided disclosure protocol (GDP) of past traumas on symptoms and clinic visits among frequent clinic attenders. METHODS: Forty-one frequent clinic attenders (> or =2 visits/3 months) took part. Patients were randomly assigned individually to either a casual content writing control group (n = 19) or a trauma content writing experimental GDP group (n = 22). GDP patients wrote about an upsetting event chronologically (day 1), verbally described their thoughts and feelings and described the event's impact on life (day 2), and finally wrote about their current perspective on and future coping with the event (day 3). Three months later, patients were reassessed blindly for symptoms and clinic visits, and an average of 15 months later they were assessed blindly for clinic visits again. RESULTS: Compared with controls, GDP patients reported lower symptom levels at 3 months (2.3 versus 5.2), and made fewer clinic visits during the 3 (1.3 versus 3.0) and 15 month (5.1 versus 9.7) follow-ups. The percentage of GDP patients making > or =10 visits during the 15 month follow-up was smaller (10%) than among controls (33%). CONCLUSIONS: The findings extend previous findings to frequent clinic users, using a new form of written disclosure aimed at shifting trauma from implicit to explicit memory. The GDP may be an inexpensive additional intervention in primary care for reducing symptoms and clinic visits among frequent clinic users.  相似文献   
4.

Background  

The elderly population consumes a large share of medical resources in the western world. A significant portion of the expense is related to hospitalizations.  相似文献   
5.
Tracheal mucormycosis presented as an intraluminal soft tissue mass   总被引:2,自引:0,他引:2  
BACKGROUND: Mucormycosis is a potentially lethal disease caused by an opportunistic fungal infection. It occurs mostly in diabetic or immunosuppressed patients and usually involves the lungs or paranasal sinuses. METHODS: We report a rare case of a patient with diabetic ketoacidosis who presented with progressive cough and dyspnea. CT of the neck and chest showed an intraluminal soft-tissue mass extending from the first tracheal ring to the thoracic inlet, causing severe destruction of the trachea. Direct laryngoscopy and biopsy demonstrated hyphal invasion with architecture typical of invasive mucormycosis. RESULTS: The patient underwent resection of the upper trachea and prolonged amphotericin B therapy and is disease free at 24 months after surgery. CONCLUSIONS: In patients with diabetes presenting with progressive hoarseness, dyspnea, and endobronchial mass, a fungal infection should be considered. In case of invasive tracheal mucormycosis, prompt diagnosis and early surgical resection may help improve survival.  相似文献   
6.
7.
Silas Weir Mitchell was held by many of his contemporaries in the United States, Great Britain and on the continent of Europe to be the greatest medical scientist in the Western Hemisphere. He is considered the founding father of American neurology and made important contributions in the fields of basic science and the delineation of diseases. He was also a best-selling novelist and a public figure of stature. According to Wilder Penfield, the eminent Canadian neurosurgeon, Mitchell was, for the last three decades of the 19th century, the outstanding psychiatrist in the United States. We examine some aspects of this claim by reviewing briefly what psychiatrists did in Mitchell's day, the role played by neurologists in the treatment of the neuroses and his own particular psychiatric interests. We conclude that, contrary to Penfield's contention, Mitchell never really practiced psychiatry beyond what any generalist of today would consider as being within his or her scope. He was, however, a mentor to the psychiatrists of his time.  相似文献   
8.
Factors linked to bacterial vaginosis in nonpregnant women   总被引:17,自引:0,他引:17       下载免费PDF全文
OBJECTIVES: The purposes of this study were to test the hypothesis that vaginal douching is linked to bacterial vaginosis in both symptomatic and asymptomatic women and to identify other demographic, reproductive, and lifestyle factors associated with bacterial vaginosis. METHODS: In this cross-sectional study involving 3 clinic sites, 496 nonpregnant women completed a self-administered questionnaire. Their vaginal smears were assessed and cross-validated for bacterial vaginosis. RESULTS: The prevalence of bacterial vaginosis across clinics ranged from 15% to 30%. In analyses restricted to site 1, adjusted odds ratios (ORs) for bacterial vaginosis remained significant for African American women with 13 or fewer years of education (OR = 5.5, 95% confidence interval [CI] = 2.1, 14.5), hormone use within the past 6 months (OR = 0.5, 95% CI = 0.2, 0.8), and vaginal douching within the past 2 months (OR = 2.9, 95% CI = 1.5, 5.6). CONCLUSIONS: Two lifestyle factors emerge as strongly associated with bacterial vaginosis: systemic contraceptives appear protective, whereas douching is linked to an increase in prevalence. The temporal relationship between douching and bacterial vaginosis needs further clarification.  相似文献   
9.
Digital beam attenuator technique for compensated chest radiography   总被引:1,自引:0,他引:1  
The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone.  相似文献   
10.
Burkholder HC  Witherspoon LE  Burns RP  Horn JS  Biderman MD 《The American surgeon》2007,73(6):574-8; discussion 578-9
With the development of expertise in image guidance for breast surgery, many surgeons now perform preoperative wire localization themselves. Use of a single wire versus multiple wires to bracket a radiographic breast abnormality has previously been described, although benefits of this technique based on clinical outcomes such as margin status, tissue volume removed, and re-excision rates have not been established. This study is a retrospective analysis of wire-localized breast biopsies performed by 14 surgeons over 29 months; stereotactic and ultrasound guidance were used. During this time, 489 wire localizations were done, of which 159 used multiple wires. Two hundred eleven of these biopsies were done for malignant disease, 86 using multiple wires. After controlling for tumor node metastases stage, single and multiple wire placements were compared using endpoints of margin status, need for re-excision, and total volume of tissue removed. Neither margin status nor re-excision was related to the number of wires placed. However, the number of wires placed was significantly related to the total volume of tissue removed. Use of more than one localizing wire was associated with greater volume of tissue removal (measured in centimeters cubed) in benign disease (46 vs 25, P < 0.001), equivalent volumes in stage 0 disease (73 vs 67), less volume in stage 1 disease (113 vs 164), and less volume in stages 2 through 4 (158 vs 207, P = 0.03). Outcomes based on surgeon case volume during the study period demonstrated that low- (1-40), medium- (41-80), and high-volume (>80) surgeons did not differ in the type or stage of breast pathology treated. Surgeons with high case volumes were more likely to place multiple localizing wires (P < 0.001) and were more likely to do a breast-conserving procedure if re-excision was performed (P < 0.018). Surgeons with low case volumes were more likely to perform a re-excision (P < 0.025). Surgeon experience has a positive impact on quality outcome measures such as performance of a definitive procedure at the time of initial surgery and use of breast-conserving procedures at the time of re-excision. Multiple wire localization can be used to significantly reduce the volume of breast tissue removed in malignant disease without sacrificing margin status or increasing the need for future re-excision.  相似文献   
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