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31.
A bleeding disorder with absent collagen-induced platelet aggregation and adhesion has been described in a patient whose platelets failed to express surface glycoprotein Ia. We studied the interaction of her platelets with subendothelium in an annular perfusion chamber and the interaction with purified human collagen type III in a rectangular perfusion system under flow conditions. Platelet adherence was almost completely absent both at low and high shear rates. The few platelets which adhered remained in the contact stage without subsequent spreading and aggregate formation. Addition of a monoclonal antibody, which was directed against the von Willebrand moiety of FVIII-VWF, to the blood, completely abolished platelet adherence at high shear rates and had a partial effect at low shear rates. These data indicate that von Willebrand factor plays a role in the initial attachment (contact stage) of platelets to subendothelium. We conclude that the bleeding disorder and excessively prolonged bleeding time in our patient are caused by a new specific defect of the platelet-vessel wall interaction.  相似文献   
32.
A 35-year-old black man with end-stage renal disease from biopsy-proven focal segmental glomerulosclerosis developed worsening function of his renal allograft 160 days after living related donor renal transplantation. Renal biopsy showed necrotizing and crescentic glomerulonephritis (NCGN) and presence of intraglomerular viral inclusions confirmed by immunocytochemical stain and in situ hybridization techniques to be cytomegaloviral in origin. Electron microscopy showed no immune complexes, and workup for other causes of NCGN was negative. The patient was treated with ganciclovir without other changes in his immunosuppressive regimen. After 8 weeks of ganciclovir therapy, a second renal transplant biopsy showed resolution of the glomerular process and disappearance of the cytomegalovirus (CMV) inclusions. The resolution of the glomerular process with treatment for CMV infection, and without other change in therapy, strongly supports a causative link between CMV and NCGN in this patient. This case represents the first report of CMV-associated NCGN in a renal transplant patient.  相似文献   
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窄蒂肋间穿支型薄皮瓣在手背创面修复中的应用   总被引:3,自引:2,他引:1  
介绍一种以肋间动脉皮肤穿支为营养血管的、主要用于修复手背皮肤缺损的薄皮瓣。手术方法是以第4~9肋间血管外侧皮穿支为蒂,蒂部长和宽均为3~5cm,瓣部长宽均可达15cm,远端2/3修薄。术后第7~10天断蒂。应用此窄蒂皮瓣修复15例16只手背创面,皮瓣全部成活。随访6个月~2年,手功能恢复良好。由于手术不需分离肋间主干血管,其操作远较以往报道的岛状或游离肋间血管皮瓣简便和安全,为修复手背创面的理想皮瓣  相似文献   
39.
This study aimed to determine the effect of hamstring botulinum toxin A (Btx-A) injection in 10 children with crouch gait in terms of changes in muscle length and lower-limb kinematics. Before Btx-A injection limb kinematics were recorded. Maximum hamstring lengths and excursions were calculated by computer modelling of the lower limb. Data were compared with the averaged hamstring lengths of 10 control children. Hamstrings were denned as short if their length was shorter than the average maximum length minus one standard deviation. Gait analysis was repeated 2 weeks after isolated hamstring Btx-A injection. Pre- and postinjection kinematic data and muscle lengths were then compared. Four of 18 injected limbs in three subjects had short medial hamstring before injection, none of the subjects had short lateral hamstrings. Muscle excursion was significantly reduced in the short and adequate maximum muscle length groups. A significant increase in the semimembranosus and semitendinosus length in all of the injected limbs was noted. Only in the short muscle group was a significant increase in muscle excursion observed. Knee extension improved by 13° in the adequate muscle length group and by 15.6° in the short muscle length group. Pelvic tilt and hip flexion increased in both groups non-significantly. Average walking speed postinjection increased from 0.60 ms-1 to 0.71 ms-1. Short hamstrings are over-diagnosed in crouch gait. Hamstring Btx-A injection in patients with crouch gait produces significant, repeatable muscle lengthening and improved ambulatory function.  相似文献   
40.
Three different modes of lactate tests were studied. Eleven male competitive swimmers performed the tests (n.100 m, n.300 m, 2.100m + 2.400 m) within 5 days. Swimming velocity (V) vs blood lactate (BLa) and V vs heart rate (HR) curves were averaged. In V vs BLa comparisons, the BLa values of 4 mmol.l-1 in 2.400 m, 3 mmol.l-1 in n.300 m, and 2 mmol.l-1 in n.100 m modes were found to correspond to the same V. Although the resting BLa values were similar before the testing occasions, the initial BLa value in very easy swimming was lower in the n.300 m than in the n.100 m mode. The elimination of lactate most probably caused this difference. The highest BLa value was measured in the n.100 m (14.9 mmol.l-1) and 2.100 m (13.6 mmol.l-1) exercise modes demonstrating a higher rate of anaerobic energy production than in the n.300 m or 2.400 m test modes. In HR vs V comparison, the n.300 m and 2.400 m modes demonstrated similar HR values in relation to V. To measure the whole intensity area, a combination of tests should be applied by performing an incremental set with several steady-state loadings (aerobic) and one or two 100 m swims (anaerobic) in one test session.  相似文献   
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