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991.
Out of 330 adult Systemic Lupus Erythematosus (SLE) cases who attended the Rheumatic Care Centre, Government General Hospital, 59 children were analysed. There was no case with onset before the age of 5 years. There were 49 females and 110 males (M:F =1∶4.9). The initial manifestations were fever (67%), arthritis (61%), skin rash (59%) and lymphadenopathy (27.1%). There was no case of Raynaud's phenomenon. Only 10.1% of patients presented with thrombocytopenic purpura. In the cumulative clinical features, arthritis in 86.6%, fever in 79.8%, skin rash in 69.4%, lymphadenopathy in 61% and hepatosplenomegaly in 39.9% were observed. Renal involvement was seen in 49.1%, neuropsychiatric manifestations in 27.1%, pleuropulmonary in 22% and cardiac manifestations in 10.2%. Anaemia was seen in 50.8%, leukopenia in 18.4%, thrombocytopenia in 11.8%, ANA in 100%, anti-dsDNA in 92.3%, anti-Sm in 34.7%, anti-SSA in 38.5%, anti-SSB in 15.4%, ACL in 30.8%, low C3 in 50% and false positive VDRL in 3.3%. Death occurred in 8 children, 3 due to infection, 2 due to renal causes, I due to cardiac and 2 due to central nervous system involvement.  相似文献   
992.
低能超声对人肺癌细胞的体外杀伤作用   总被引:2,自引:0,他引:2  
Zhan X  Wang Y  Lai B 《中国肺癌杂志》2000,3(6):455-457
目的 探讨低能超声对人肺癌细胞的影响。方法 用低能量连续波超声处理小细胞肺癌细胞系SM、腺癌细胞系A2及人肺纤维母细胞FB,用胎盘蓝染料排斥试验及克隆存活试验判定效果,结果 低能量(0.8W/cm^2)超声3分钟分各种人肺癌细胞及人肺纤维母细胞有杀伤作用(P〈0.05),10分钟可杀死全部细胞(P〈0.001),细胞浓度越高,杀伤作用越低,超声10分钟后含细胞悬液的试管内温度未见显著上升,声强0.8W/cm^2的超声使阿霉对肺癌细胞SM的杀伤作用增加100倍(P〈0.001),结论 低能连续波超声可杀伤肺癌细胞,并能显著增加阿霉素对肺癌细胞的细胞毒性。  相似文献   
993.
AIMS: Parametric imaging of myocardial perfusion provides useful visual information for the diagnosis of coronary artery disease (CAD). We developed a technique for automated detection of perfusion defects based on quantitative analysis of parametric perfusion images and validated it against coronary angiography. METHODS AND RESULTS: Contrast-enhanced, apical 2-, 3- and 4-chamber images were obtained at rest and with dipyridamole in 34 patients with suspected CAD. Images were analyzed to generate parametric perfusion images of the standard contrast-replenishment model parameters A, beta and A.beta. Each parametric image was divided into six segments, and mean parameter value (MPV) was calculated for each segment. Segmental MPV ratio between stress and rest was defined as a flow reserve index (FRI). Receiver operating characteristics (ROC) analysis was used in a Study group (N=17) to optimize FRI threshold and the minimal number of abnormal segments per vascular territory (LAD and non-LAD), required for automated detection of stress-induced perfusion defects. The optimized detection algorithm was then tested prospectively in the remaining 17 patients (Test group). LAD and non-LAD stenosis >70% was found in 19 and 17 patients, respectively. In the Study group, FRI threshold was: LAD=0.95 and non-LAD=0.68, minimal number of abnormal segments was four and two, correspondingly. Sensitivity, specificity and accuracy in the Test group were: 75%, 67% and 71% in the LAD, and 75%, 75% and 75% in the non-LAD territories. CONCLUSION: Automated quantitative analysis of contrast echocardiographic parametric perfusion images is feasible and may aid in the objective detection of CAD.  相似文献   
994.
Many children with cerebral palsy (CP) suffer from feeding disorders. Twenty children with spastic CP and 20 neurologically normal children (age range 6.2–12.9 years) were monitored with ultrasound imaging of the oral cavity synchronized with surface electromyographic (EMG) recordings of masseter and infrahyoid museles and respiratory inductance plethysmograph (RIP) recordings during feeding tasks. A lip-cup contact detector signaled contact of the drinking cup on the lip during liquid tasks. Children with CP required more time than normals for collection and organization of 5 ml and 75 ml liquid boluses for swallowing. The ventilatory preparation phase, recovery to baseline resting ventilatory pattern after swallowing, and total time for task completion were longer in children with CP for 5-ml and 75-ml tasks. The interval from lip-cup contact until alteration of ventilation from baseline resting ventilatory pattern was longer for children with CP during 75-ml tasks but not for 5-ml tasks. The interval from completion of the task-related cookie swallow until initiation of the next swallow was longer in children with CP than in normal children. These data provide evidence than children with CP manage solid boluses more easily than liquid boluses and small liquid boluses more easily than large liquid boluses. This investigation statistically confirms empirically based recommendations that children with CP be allowed more time to complete feeding tasks and consume small volume drinks rather than large volume drinks.  相似文献   
995.
The most prominent and most discussed local side effect of topical corticosteroids is the thinning of the skin. Therefore, the atrophogenic potential is an important indication of the quality of a new corticosteroid. Several studies have been conducted to investigate this parameter. In rats, the effect of breaking strength of the skin, the most appropriate model for evaluating atrophogenicity in animals, showed that MPA and prednicarbate (PC) reduced the breaking strengh only slightly compared to clobetasol propionate (CBP). These results indicate that MPA could be classified as a corticosteroid with low local atrophogenic potential. This was confirmed in humans by a placebo controlled double-blind study comparing intra/interindividuals MPA (cream, ointment and fatty ointment) and bethamethasone-17-valerate (BMV), CBP and PC (cream only) under occlusive dressing over 6 weeks. Three different parameters were assessed (dermal atrophy (clinical picture), surfometric measurement of the dermatoglyphic pattern, visual evaluation of telangiectasia). In all three formulations, MPA is of lower atrophogenic potential than CBP. While there is no statistical difference between BMV and MPA, the atrophogenic potential of MPA is low. In order to reflect more the clinical use of topical corticosteroids, MPA preparations (cream 0.1% and fatty ointment) has been evaluated in comparison to BMV in an 8-week non-occluded application test. MPA was applied once a day (5 days a week) and BMV twice in 20 healthy subjects according to a double-blind randomized design. Assessment of atrophogenic potential was performed weekly using clinical scores (atrophy and telangiectasia) as main criteria and skin thickness measurements (ultrasound imaging) as a second criterion. BMV cream gives higher numbers of telangiectasia than MPA preparations and vehicles. From the skin thickness measurements, MPA treatments once a day has a lower thinning potential than BMV twice a day. These findings were confirmed by clinical trials. In 1145 patients suffering from various types of eczema who used MPA in cream and ointment, mild atrophy of the skin was observed in only one patient. Moreover, clinical signs of atrophy were present in only two out of a group of 673 patients (590 adult and 83 children) treated with MPA fatty ointment. In a group of 66 patients who used this same MPA fatty ointment during 3–4 months, no signs of skin atrophy were observed. Considering animal and human studies, MPA can be classified as a corticoid with low atrophogenic potential.  相似文献   
996.
Renal imaging has dramatically improved since the introduction of ultrasound (US), computed tomography (CT), and most recently magnetic resonance (MR) imaging. US and MR imaging are ideal for patients with compromised renal function preventing administration of iodinated contrast material or those who have experienced reactions to contrast. Staging errors occur due to limitations in assessing microscopic tumor invasion of the renal capsule and perinephric fat, detecting metastatic deposits in normal sized lymph nodes and differentiating inflammatory hyperplastic lymph nodes from neoplastic ones. These limitations are shared by US, CT, and MR imaging. Vascular invasion by tumor can be evaluated by all imaging modalities including venography. The advantages and limitations of each examination will be presented.  相似文献   
997.
Perineurioma is an extremely rare benign tumor of the peripheral nervous system composed exclusively of perineurial cells. Imaging findings of this tumor are non-specific and the diagnosis is based on histologic studies. We report a case of perineurioma of the kidney in a 7-year-old girl discovered incidentally during the evaluation of a urinary tract infection. This is the first case of renal perineurioma reported in a child. We present the ultrasound and computed tomography findings of this histologically confirmed neoplasm. Received 13 January 1997; Revision received 27 June 1997; Accepted 18 July 1997  相似文献   
998.
The purpose of our study was to compare power Doppler sonography (US) and conventional color Doppler US in the diagnosis of acute appendicitis by revealing local signs of hyperemia. One hundred consecutive patients (46 males and 54 females, ages 7–61 years; mean, 24.7 years) with clinically suspected acute appendicitis were prospectively examined with power Doppler US and conventional color Doppler US. Of 38 patients who subsequently underwent surgery, appendicitis was proven in 34. The remaining 62 patients who were not submitted to surgery had no clinical evidence of appendicitis over a 2- to 6-month follow-up. At gray-scale US, the appendix was visualized in 30 (88.2%) of the 34 cases with pathologically proven acute appendicitis. Power Doppler US depicted a moderate to marked hypervascularity of the appendiceal wall and surrounding mesoappendix in 28 (93.3%) of these 30 patients. At conventional color Doppler US, flow signal within the appendiceal wall and surrounding mesoappendix was shown in only 21 (70%) of 30 cases (P<0.05). No false-positive diagnosis was made at either power or color Doppler US among the 62 patients without appendicitis. Power Doppler US is more sensitive than conventional color Doppler imaging for revealing signs of local hyperemia in acute appendicitis.  相似文献   
999.
Summary The square of ultrasound transmission velocity in a material is correlated to the modulus of elasticity, which is an indicator of its mechanical properties. This might make the measurement of ultrasound transmission velocity useful in the noninvasive diagnosis of bone diseases. Bone, however, is not an isotropic material but is architecturally structured. The aim of our study was to investigate and especially to quantify the influence of architecture in cortical bone on ultrasound transmission velocity. Twenty-two rectangular, flat specimens of cortical bone were prepared from diaphysis of fresh pig radius. Ultrasound transmission velocity was measured parallel and perpendicular to direction of Haversian channels. It was found to be 3647 ± 41 m/s parallel to and 2821 ± 29 m/s perpendicular to Haversian channels respectively (p<0.001). Our results clearly indicate that there is an important influence of architecture in cortical bone on ultrasound transmission velocity which has to be taken into account in its clinical use.  相似文献   
1000.
Abstract The objective was to test the hypothesis that there is a correlation between thinning of the skin and bone in patients on chronic oral glucocorticoids (GCs). This was a one-time cross-sectional analysis performed in an academic referral center. The study group consisted of 14 patients on GCs for a variety of disorders, including dermatomyositis, pemphigus vulgaris, pyoderma gangrenosum, and urticarial vasculitis. Skin thickness was compared with that of 24 sex- and age-matched controls. The main outcome measures were the bone density of the lumbar spine (L2–L4) and the skin thickness. The skin thickness (mm, mean ± SEM) in GC-treated (n = 7) vs unmedicated age-matched Caucasian women (n = 20) was 0.84 ± 0.04 vs 1.02 ± 0.04 (t = 3.07, P < 0.01) in the upper arm, 1.13 ± 0.09 vs 1.49 ± 0.05 (t = 3.65, P < 0.002) in the dorsal forearm, and 0.96 ± 0.07 vs 1.17 ± 0.02 (t = 2.92, P < 0.01) in the ventral forearm. L2–L4 bone densities averaged 106 ± 2% in the GC-treated female patients relative to the age and sex-matched controls. There was no correlation between skin thickness and bone density. In GC-treated (n = 4) vs unmedicated Caucasian men matched for age (n = 4), skin thickness was 1.09 ± 0.4 vs 1.33 ± 0.05 (t = 3.51, P < 0.02) in the upper arm, but was not significantly different at the two forearm sites. No correlation between skin thickness and bone density was observed. The level of type I procollagen mRNA in skin from three GC-treated patients was 45% of the value in three age-matched controls. In conclusion, GCs cause statistically significant thinning of skin independently of the effects on bone. Received: 19 November 1997  相似文献   
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