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近年来由于训练强度不断增大,高水平运动员心律失常的发生率显著增加。本文研究资料表明,男心律失常组安静时心搏量明显大于正常组(P<0.05),而运动后心搏量降低(正常组心搏量增加),说明心律失常的运动员心脏储备能力差,心脏泵血功能降低,应予慎重对待。  相似文献   
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This study analyzed the feasibility of fitting keratoconus-affected corneas with nonkeratoconus rigid gas-permeable (RGP) contact lenses. We retrospectively studied patients with a diagnosis of keratoconus in the past 10 years who were fitted successfully with nonkeratoconus RGP lenses by the same physician. Results confirmed nonkeratoconus RGP lenses as the first-line correction tool. Additionally, we found a simple equation to speed the choice of the base curves of the lenses. The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer or provider of services discussed in this article.  相似文献   
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BACKGROUND AND PURPOSE: Fluorine-18-2-deoxy-D-glucose (18F-FDG) has been used in the clinic as a diagnostic radiotracer for monitoring many kinds of tumors, but its value for monitoring fibrosarcoma is not well established. METHODS: In this study, the uptake of 18F-FDG in a fibrosarcoma-bearing mouse model was evaluated using the high resolution positron emission tomography (PET) system microPET. Tumor cells were implanted in 3 FVB/N mice, and static microPET scanning was performed on day 1, 7, 12 and 15 after implantation. A dynamic microPET image was scanned on day 12 to determine the 18F-FDG uptake in 3 other tumor-bearing mice. Time-activity curves were plotted by drawing regions of interest in the tumor, liver, kidneys and muscles. The mice were sacrificed after dynamic microPET imaging and whole-body autoradiography (WBAR) was performed. For biodistribution study, 9 tumor-bearing mice, 3 per experimental group, were studied at 3 time points and the results were compared with the static microPET images. RESULTS: MicroPET images suggested that 18F-FDG could be used to monitor the growth of tumors 7 days after implantation. Dynamic scans of 18F-FDG uptake reached a plateau in the tumor after 20 minutes on day 12 after implantation. Both microPET and WBAR revealed evidence of tumor necrosis. The results of biodistribution and WBAR agreed with those from microPET images. CONCLUSION: MicroPET was useful for monitoring the growth of fibrosarcoma and determination of the maximal uptake time point of 18F-FDG in tumors in this tumor-bearing mouse model.  相似文献   
15.
PURPOSE: This study was an analysis of the soft and hard tissue changes of the facial profile after bilateral sagittal splitting osteotomy for mandibular setback of Taiwanese patients. PATIENTS AND METHODS: We collected pre- and postsurgical lateral cephalographs of 64 patients (28 males, 36 females) with skeletal Class III malocclusion who received combined orthodontic-surgical treatment with bilateral sagittal splitting osteotomy mandibular setback at Taipei Veterans General Hospital between 1994 and 2000. Nineteen cephalometric parameters of (14 linear, 4 angular, and the BS index) soft and hard tissues were measured at 1 week before treatment, and 2 months and 1 year after surgery, and analyzed by paired t test. RESULTS: Mean patient age was 20.0 +/- 1.6 years. The patients underwent an average of 7 mm mandibular setback at the osseous pogonion (Pog). Average setbacks at Pog and soft tissue pogonion (pog) were 5.54 mm and 4.85 mm, respectively, at 1 year after surgery. The setback ratio of Pog/pog was 1:0.88. The hard tissue relapse at Pog was 21% at 1 year after surgery. Improvement in prognathic profile was demonstrated by significant changes in the positions of Pog and pog, ANB angle, the distance from lower lip to esthetic line (E-L lip), and the BS index after surgery. However, compared with parameters obtained from a normal Taiwanese population, the cephalometric data of Pog, pog, and BS index still indicated mild prognathism. CONCLUSION: Although mandibular prognathism could be grossly improved by bilateral sagittal splitting osteotomy mandibular setback, a significant amount of relapse occurred within 1 year after surgery. The extent of the postoperatively preserved features showing mandibular prognathism should be a concern for both patients and physicians.  相似文献   
16.
This study, evaluating the effects of hyperthyroidism (HT) in oesophageal motility, depended on an oesophageal radionuclide transit test. A modified standard method was used to calculate: (a) total mean transit time (MTT), (b) residual fraction (RF) and (c) retrograde index (RI) in a supine position. Eighteen untreated patients with HT and 25 normal volunteers (NV) with a similar age distribution were included in this study. The results showed that oesophageal motility in patients with HT was worse than in the normal controls (P < 0.05 by Student's t-test). The correlation of MTT, RF and RI with size and function of thyroid glands in the patients with HT were calculated to explain the effects of HT in oesophageal motility. The results showed that neither the size nor the function of the thyroid glands in HT affected oesophageal motility.  相似文献   
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We report the findings of spinal magnetic resonance imaging (MRI) in 2 patients who had undergone intrathecal chemotherapy and presented with the subacute onset of ascending numbness and weakness. MRI revealed a symmetric hyperintensity at the posterior columns of the spinal cord from the lower cervical region down to the conus medullaris level on T2-weighted images, and no abnormal enhancement. The imaging findings are similar to those seen in subacute combined degeneration (SCD), but the serum vitamin B(12) levels were normal in these 2 cases.  相似文献   
19.
Plasma lipid concentrations and high density lipoprotein (HDL) subclass distributions were evaluated in 22 newborn infants nourished with intravenous (iv)-fat. The majority of infants were premature with respiratory distress syndrome. Based on baseline (prior to iv-fat) HDL subclass profiles determined by gradient gel electrophoresis (GGE), infants fell into two classes, one with two or more pronounced peaks within the normal HDL spectrum (group I, 17 subjects) and the other with highly unusual HDL distribution (group II, five subjects). Total plasma cholesterol increased in both groups during low and high fat intravenous feeding. HDL-cholesterol, however, did not change with iv-fat where mean values for groups I and II at baseline, iv-low fat and -high fat were: group I, 31.2 +/- 7.1, 30.0 +/- 8.8, and 36.6 +/- 16.7 mg/dl, respectively; and group II, 20.0 +/- 7.8, 20.2 +/- 7.4, and 19.8 +/- 8.8 mg/dl, respectively. Unlike HDL-cholesterol levels that remained constant with iv-fat, apolipoprotein (apo) AI concentrations increased significantly: group I, 73.0 +/- 11.0, 88.3 +/- 15.9, and 93.1 +/- 21.9 mg/dl, respectively; and group II, 31.8 +/- 10.5, 41.0 +/- 12.8, and 59.3 +/- 18.5 mg/dl, respectively. In group I infants, iv-fat is associated with an increase in larger-sized particles, particularly in the (HDL2b)gge range; in group II there is an increase in (HDL3b)gge and (HDL3c)gge components and a disappearance of particles that fall outside of the size range of normal HDL. In both groups, enteral feeding is associated with a further normalization of HDL subclass distribution. The aberrant GGE profiles and very low apoAI levels of group II infants at baseline were associated with unusual HDL morphology determined by electron microscopy where discoidal structures were prominent. With iv-fat, discoidal particles decline in number while normal spherical structures increase. Prevalence of discoidal HDL at baseline was associated with low concentrations of lecithin:cholesterol acyltransferase (LCAT) (1.12 +/- 0.5 micrograms/ml); with iv-fat this enzyme rose to 1.61 +/- 0.18 micrograms/ml. Increased LCAT is associated with the normalization of HDL morphology. It is likely that iv-fat improves the nutritional status of premature infants, thereby stimulating increased liver synthesis of important proteins, including apoAI and LCAT, associated with HDL metabolism.  相似文献   
20.
用国产恩威牌洁尔阴对阴道常见七种细菌进行抑菌试验,结果该药对其中五种细菌有明显抑菌作用,本文为洁尔阴治疗细菌性阴道炎提供了实验依据。  相似文献   
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