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81.
The study was performed to investigate subclinical abnormalities in regional cerebral blood flow (rCBF) in patients with insulin-dependent diabetes mellitus (IDDM) and to correlate them with patients' characteristics. After intravenous injection of technetium-99m hexamethylpropylene amine oxime (HMPAO), tracer uptake of the prefrontal, frontal and parieto-occipital zones was measured with a triple-head single-photon emission tomography (SPET) camera system in 35 IDDM patients outside an episode of hypoglycaemia. Tracer uptake values in 16 age- and sex-matched healthy volunteers served as reference values. Compared with healthy subjects, increased tracer uptake of both prefrontal regions and the left frontal region could be shown in diabetes. Tracer uptake was negatively correlated with the duration of diabetes in all investigated regions. In diabetic patients with a disease duration of more than 5 years (n=26), stepwise regression analysis revealed a significant positive correlation between their HbA1c levels and tracer uptake. Long-term diabetic patients with reduced (pre)frontal tracer uptake (n=8) had lower HbA1c levels than those without (8.4%±0.2% vs 9.3%±0.3%,P<0.05) and tended to have more frequently a history of hypoglycaemic coma (6/8 vs 6/18,P=0.06). It can be concluded that duration of diabetes contributes to subclinical changes in basal rCBF in IDDM as detected with HMPAO SPET of the brain. The positive correlation between the presence of regional hypoperfusion and lower HbA1c levels in long-term diabetic patients may be interpreted in the light of a presumed higher incidence of hypoglycaemia as metabolic control improves.  相似文献   
82.
The aim of this case report is to describe the time course of S-100 serum levels of a patient, after severe head injury, whose blood sample could be drawn very soon after injury. The results were compared to a group of patients in which a correlation between S-100 serum levels and outcome after traumatic brain injury could be demonstrated. Blood samples were taken on admission (mean 2.3 hours), 6, 12 and 24 hours after trauma and then every 24 hours up until and including the fifth day. The outcome was estimated on discharge using the Glasgow Outcome Scale. The S-100 serum level of the patient described in the case report with a favourable outcome had initially risen to 10.0 micrograms/l and showed a rapid decline. In the previous group, patients with unfavourable outcome had a S-100 serum level of 7 micrograms/l mean concerning the first probe (after 2.3 hours mean) compared to 1.5 micrograms/l mean (after 2.23 hours mean) in patients with favourable outcome (p < 0.05). In comparison to the literature, there seems to be differences regarding the enzyme liberation in stroke and head injury. Therefore, S-100 serum levels need to be interpreted with regard to collection time and underlying pathology.  相似文献   
83.
B H Doft  D J Metz  S F Kelsey 《Ophthalmology》1992,99(11):1728-34; discussion 1734-5
PURPOSE: A study was performed to determine if diabetic subjects who fail to respond to initial panretinal photocoagulation with regression of retinopathy risk factors do better with supplemental panretinal photocoagulation. METHODS: Thirty-five patients with 3 or more retinopathy risk factors who failed to respond to panretinal photocoagulation with regression to less than 3 retinopathy risk factors by 3 weeks after initial panretinal photocoagulation were prospectively randomized to augmentation laser panretinal photocoagulation (MORE) or to no additional treatment (NOMORE). RESULTS: Six months after initial treatment, the MORE group (n = 16) had regressed a mean of -0.94 retinopathy risk factors (with 95% confidence interval [CI] -1.60 to -0.26), compared with -0.21 retinopathy risk factors (95% CI -0.69 to 0.27) in the NOMORE (n = 19) group (P = 0.055). However, by 1 year, there was no statistically significant difference in the amount of regression of retinopathy risk factors with a mean decrease of -1.12 (95% CI -2.0 to -0.24) versus -1.05 retinopathy risk factors (95% CI -1.80 to -0.28) in the 2 groups, respectively. Similarly, for visual acuity, there was no difference in outcome. For all study patients, the persistence of three or more retinopathy risk factors was associated with a poorer visual result than if there was regression to less than three retinopathy risk factors. CONCLUSION: This study shows that although augmentation panretinal photocoagulation achieved faster regression of retinopathy risk factors, by 1 year, there was no difference in either mean regression of retinopathy risk factors or visual acuity between eyes treated or not treated with augmentation panretinal photocoagulation. In addition, the study shows that the persistence of 3 or more retinopathy risk factors 1 year after treatment was associated with a poorer visual result. Because sample size limited the power of the study to find small differences between groups, and because in proliferative diabetic retinopathy small differences could be important clinically, the authors do not recommend changes in current clinical practice.  相似文献   
84.
Minocycline has immunomodulatory and neuroprotective activities in vitro and in an animal model of multiple sclerosis (MS). We have previously reported that minocycline decreased gadolinium-enhancing activity over six months in a small trial of patients with active relapsing-remitting MS (RRMS). Here we report the impact of oral minocycline on clinical and magnetic resonance imaging (MRI) outcomes and serum immune molecules in this cohort over 24 months of open-label minocycline treatment. Despite a moderately high pretreatment annualized relapse rate (1.3/year pre-enrolment; 1.2/year during a three-month baseline period) prior to treatment, no relapses occurred between months 6 and 24. Also, despite very active MRI activity pretreatment (19/40 scans had gadolinium-enhancing activity during a three-month run-in), the only patient with gadolinium-enhancing lesions on MRI at 12 and 24 months was on half-dose minocycline. Levels of the p40 subunit of interleukin (IL)-12, which at high levels might antagonize the proinflammatory IL-12 receptor, were elevated over 18 months of treatment, as were levels of soluble vascular cell adhesion molecule-1. The activity of matrix metalloproteinase-9 was decreased by treatment. Thus, clinical and MRI outcomes are supported by systemic immunological changes and call for further investigation of minocycline in MS.  相似文献   
85.
In dermographic urticaria (DU), shearing forces on the skin result in weals and itching. Second-generation antihistamines are recommended as the first-line treatment, but to date only a few have ever been tested for this condition. The objective of this pilot study was to assess the safety and efficacy of ebastine in preventing symptoms of DU. Seven adult patients with DU participated in a double-blind cross-over trial of ebastine 20 mg. Safety was assessed using a sensitive psychometric battery, testing cognitive performance and mood. Efficacy was assessed by rating weals, erythema, pruritus and burning after challenge. Ebastine had no negative effective on cognitive performance or mood. Weals, pruritus and burning were greatly reduced for most subjects. This pilot study suggests that ebastine is safe and effective in preventing the symptoms of DU and should be tested on a larger scale.  相似文献   
86.
M Ishida  K Doi  L N Loo  C E Metz  J L Lehr 《Radiology》1984,150(2):569-575
Detection studies of simulated low-contrast radiographic patterns were performed with a high-quality digital image processing system. The original images, prepared with conventional screen-film systems, were processed digitally to enhance contrast by a "windowing" technique. The detectability of simulated patterns was quantified in terms of the results of observer performance experiments by using the multiple-alternative forced-choice method. The processed images demonstrated a significant increase in observer detection performance over that for the original images. These results are related to the displayed and perceived signal-to-noise ratios derived from signal detection theory. The improvement in detectability is ascribed to a reduction in the relative magnitude of the human observer's "internal" noise after image processing. The measured dependence of threshold signal contrast on object size and noise level is accounted for by a statistical decision theory model that includes internal noise.  相似文献   
87.
BACKGROUND: Patients with chronic urticaria (CU) frequently exhibit positive skin test reactions to autologous serum (ASST). Therapies aimed at inducing tolerance to circulating histamine-releasing factors in ASST+ CU patients, e.g. by treatment with autologous whole blood (AWB), have not yet been tested. OBJECTIVE: To test whether ASST+ CU patients can benefit from repeated low-dose intramuscular injections of AWB. METHODS: We characterized CU severity and duration, anti-Fc(epsilon)RI and anti-IgE expression, use of antihistamines, and quality of life in 56 CU patients (ASST+: 35, ASST-: 21) and assessed the therapeutic effects of 8 weekly AWB injections in a randomized, placebo-controlled, single-blind, parallel-group trial. RESULTS: Numbers, size, intensity, and/or duration of CU symptoms, quality of life, as well as expression of anti-Fc(epsilon)RI or anti-IgE were similar in ASST+ and ASST- CU patients. However, CU in ASST+ patients was of longer duration and required markedly more antihistaminic medication. Interestingly, ASST+ patients, but not ASST- patients, showed significantly (1) reduced CU activity, (2) decreased use of antihistamines, and (3) improved quality of life after AWB treatment. Placebo treatment was ineffective in both groups, but differences of AWB and placebo treatment responses did not achieve statistical significance in either group, most likely due to the limited number of patients treated. CONCLUSION: Our findings suggest that ASST+ CU is clinically different from other CU subforms and that ASST+ CU patients can benefit from AWB therapy.  相似文献   
88.
89.
Human chorionic gonadotropin (HCG) from a testicular tumor histologically diagnosed from its metastases to be a malignant teratoma induced elevated testosterone levels and subsequent precocious isosexual development in a 12-year-old boy. The endocrinologic consequences of long term ectopic HCG production in the prepubertal male are discussed. The case report illustrates the value of HCG serum levels as a marker for tumor activity.  相似文献   
90.
We describe a case of primary lymphatic dysplasia in a newborn, presenting with lymphedema, chylothorax, and chylous ascites. Malfunction of the lymphatic system, which is supposed to cause this rare disorder, could also be responsible for a number of cases of non-immunologic hydrops fetalis.  相似文献   
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