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81.
Three clinical phenomena have been defined in the last decade in patients with diabetes mellitus as a dangerous iatrogenic sequel of hypoglycemia. These are hypoglycemia unawareness, defective glucose counterregulation and a lowered hypoglycemic threshold for hypoglycemic symptoms. Former mild hypoglycemia episodes cause a decrease and a delay in the protective hormonal counterregulatory response and warning symptoms in subsequent episodes, and in the absence of these, risk of severe hypoglycemia increases considerably. It has been demonstrated that when protection is provided against hypoglycemia with strict monitoring programs designed to avoid even mild hypoglycemia episodes, blunted autonomic symptoms and counterregulatory hormonal responses are rectified. Therefore, the best course of action in the treatment of pediatric diabetes mellitus is frequent blood sugar measurements, flexible multiple dose insulin regimens facilitating insulin dose adjustments as required, and a diet. In order to implement this, it is essential to organize an intensive training program with the patient and family, and to provide psychological support and close coordination with the diabetes treatment team.  相似文献   
82.
Congenital dyserythropoietic anemia type I (CDA I) is a rare inherited hematological disorder characterized by macrocytic anemia and ineffective erythropoiesis with pathognomonic morphological features that include internuclear chromatin bridges, spongy heterochromatin, and invagination of the cytoplasm into the nuclear area in erythroid precursors. Treatment of anemia with the usual hematinics is without effect and 15% of patients need chronic transfusions. Successful treatment of CDA I with interferon-alpha was noted. The authors report a patient with CDA I who had required transfusions every 2-3 months since the neonatal period and responded to recombinant interferon-alpha therapy with the findings of electron microscopic investigations.  相似文献   
83.
The incidence studies on hypoglycemia in Type 1 Diabetes have revealed that the younger the child the more frequent and severe are the hypoglycemic episodes. The brain does not store glycogen and perform gluconeogenesis, it relies on a continuous supply of glucose from blood. There are several studies demonstrating the brain's ability to use lactate, alanine and ketone as alternative fuels yet there is no evidence showing that this mechanism works in diabetic individuals. During hypoglycemia, cerebral blood flow increases very little in children. It is unlikely that this mechanism alone explains the maintenance of glucose utilization. Up regulation of GLUT transporters may be an additional or alternative protective mechanism. Severe hypoglycemic episodes experienced particularly in early childhood can cause deterioration in neurocognitive functions. There are significant individual differences in terms of vulnerability to hypoglycemia. Adaptive responses to hypoglycemia might vary according to both the degree and frequency of prior hypoglycemia and the presence of structural brain changes induced by chronic hyperglycemia.  相似文献   
84.
We investigated the influence of early awakening and related factors on onset of cerebrovascular disease (CVD). Totally 1199 stroke patients, in whom the onset time was known, at 3 reference hospitals were included in this study. The effects of demographic, medical, and pathophysiological factors on the circadian pattern of an unselected series of patients with ischemic stroke were analyzed. Nine-hundred seventeen CVD patients with cerebral infarction (CI), 240 patients with intracerebral hemorrhage (CH), and 42 patients with subarachnoid hemorrhage (SAH) were identified. The greatest portion of strokes (32.5%) occurred between 03:00 and 06:00 a.m. Nearly one half of the strokes in this series occurred in the very early- to mid-morning hours. This analysis of strokes provides strong evidence with a higher risk in the early morning hours (03:00 a.m. to 06:00 a.m.), and lower risk during the night time period (21:00 p.m. to midnight). Approximately 1 of every 3 strokes (1 of 3 ischemic strokes, 1 of 6 hemorrhagic strokes, and 1 of 8 subarachnoid hemorrhages) is attributable to the early morning excess. This difference tried to be explained by three ways: cold weather, religious factors, and physiological mechanisms.  相似文献   
85.
PURPOSE: This study evaluated the surface microhardness and flexural and compressive strengths of five luting cements and compared the degree of conversion of dual and autopolymerized forms of four resin-based luting cements. MATERIALS AND METHODS: Four resin composite luting cements-Panavia F, Variolink 2, RelyX Unicem Applicap, and RelyX ARC-and a polycarboxylate cement (Durelon, control group) were used in three-point bending, compression, and Vickers hardness tests following water storage for 1 week. Resin composite cements were additionally investigated with both dual and autopolymerization techniques under Fourier transformed infrared spectroscopy. Differences were analyzed using one-way ANOVA. RESULTS: The highest flexural strengths were obtained with Variolink 2 (90 MPa, SD 22), whereas the lowest were observed with Durelon (28 MPa, SD 4). RelyX Unicem showed the highest hardness values (44 HV, SD 5), whereas Variolink 2 gave the lowest (32 HV, SD 6). The highest compressive strengths were obtained with RelyX Unicem (145 MPa, SD 32), whereas the lowest were observed with Durelon (41 MPa, SD 17). For both dual and autopolymerized groups, RelyX ARC showed the highest degrees of conversion (81% and 61%, respectively) and RelyX Unicem had the lowest (56% and 26%, respectively). CONCLUSION: Resin composite luting cements of similar chemical characterizations differed in their physical properties, and polymerization method influenced their degree of conversion.  相似文献   
86.
We report a case presenting with massive overdose of hydroxychloroquine who survived without any sequelae. A 17-year-old girl presented to the Emergency Department 45 min after the ingestion of 22 g of hydroxychloroquine in a suicide attempt. We believe this is highest dose yet reported in the medical literature. The patient developed hypotension, life-threatening ventricular arrhythmias and mild hypokalemia. She was managed with saline infusion and dopamine for hypotension, gastric lavage and activated charcoal for decontamination, lidocain, magnesium sulfate and defibrillation for pulseless ventricular tachycardia. Potassium replacement and bicarbonate administration were performed. Quick treatment of hypotension, gastric decontamination, continuous long-term cardiac monitoring, and treatment of arrhythmias are the cornerstones of hydroxychloroquine overdose management.  相似文献   
87.
Solitary eosinophilic granuloma of sternum   总被引:1,自引:0,他引:1  
Primary bone tumors of the chest wall are uncommon, although a wide variety of both benign and malignant tumors arise within the chest wall. Among those tumors, sternal tumors are rare and usually malignant. We report an extremely rare case of eosinophilic granuloma developed in the sternum in a 30-year-old woman. She presented anterior chest pain and somewhat tender mass over the sternum. Chest roentgenogram, computed tomography scanning of the thorax, and total body bone scintigraphy revealed an isolated lytic lesion in the corpus sterni. A tru-cut biopsy of the mass exhibited the typical histologic appearance of eosinophilic granuloma. The solitary lesion was removed completely surgically. This rare condition should be kept in mind in differential diagnosis of sternal lesions.  相似文献   
88.
In this article the author describes 2 cases of a distally based perforator medial plantar flap that were transferred successfully from the nonweight-bearing instep region to the weight-bearing plantar forefoot (defects, 8 x 5 cm and 6 x 5 cm respectively). This flap is nourished solely by perforators of the medial plantar vessels. The advantages of this flap are the protection of the vascular supply of the foot (because both posterior tibial and medial plantar vascular systems are preserved), anterograde flow of the vascular supply (which gives an additional advantage of expecting less venous insufficiency compared with reverse-flow flaps), no dependence on retrograde vascular communications, minimal donor site morbidity, and transport of structurally similar tissues to the plantar forefoot.  相似文献   
89.
OBJECTIVES: The aim of this study is to investigate erectile response to intraurethral administration of papaverine in rats. MATERIAL AND METHODS: Male Sprague-Dawley rats were used in this study. Under urethane anesthesia, penis was exposed and intracavernous pressure (ICP) was recorded through a 23-gauge needle, which was inserted into right corpus cavernosum. Effects of intraurethral application of incremental doses of 0.2 ml papaverine gel (4-17.5 mg) on intracavernosal pressure were observed and compared with those of 0.4 mg papaverine applied into corpus cavernosum. Mean arterial blood pressure (MABP) and heart rate were also monitored. RESULTS: The mean basal ICP was 8.9 +/- 1.8 mm Hg. Intraurethral administration of papaverine did not increase ICP at any doses used in this study. After intracavernous injection of papaverine (0.4 mg), a significant increase in the ICP occurred from resting (8.9 +/- 1.8 mm Hg) to a peak at 57.5 +/- 9.9 mm Hg and persisted for 22.3 +/- 6.7 minutes (p < 0.05). The latter application significantly decreased MABP (22.3 +/- 3.1 mm Hg; p < 0.05). CONCLUSIONS: Intraurethral administration of papaverine does not seem to be an alternative to other erectile dysfunction treatment modalities. However, further studies on animals are necessary at higher concentrations or in combination with other mucosal enhancers to increase the effect of intraurethral administration of papaverine.  相似文献   
90.
Aslar AK  Kuzu MA  Elhan AH  Tanik A  Hengirmen S 《Injury》2004,35(8):746-752
BACKGROUND: Markers of dysoxic metabolism and scoring systems for triage have been widely used in critically injured patients. However, so far, no model is sufficiently reliable to predict the outcome in trauma victims. The purposes of the present study, therefore, were to determine whether a correlation exits between the main trauma scoring systems and the markers of dysoxic metabolism. Moreover, to assess if any of the admission parameters can be used to indicate outcome. METHODS: Sixty-four patients were included in this study. Admission data, including arterial lactate level, base deficit (BD), pH, revised trauma score (RTS), injury severity score (ISS), shock index (SI), and Acute Physiology and Chronic Health Evaluation (APACHE II), were collected and analysed by logistic regression analysis. Degree of association between continuous variables were calculated by either Pearson's or Spearman's correlation coefficient, where applicable. The dependence of lactate on two or more other variables was evaluated by multiple linear regression analysis. RESULTS: Logistic regression analysis showed that the fatal outcome following major torso trauma was principally associated with the APACHE II score and lactate. The specificity and the sensitivity of this logistic regression model was 94.6 and 79.2%, respectively. According to standardised linear regression coefficients, BD was the best single predictor of lactate, and APACHE II added a small amount of predictive power. The proportion of total variation in lactate level explained by base deficit, APACHE II and age is R2=85.2%. CONCLUSION: APACHE II score and the arterial lactate level are the most important determinants of clinical outcome in critically injured patients. A correlation exits between lactate and APACHE II and between lactate and base deficit.  相似文献   
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