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Retroperitoneoscopic lumbar sympathectomy   总被引:6,自引:0,他引:6  
We present a series of 27 consecutive unselected patients who underwent 29 retroperitoneoscopic lumbar sympathectomies. There were 21 male patients and six female patients, with a mean age of 45 years (RANGE, 21 to 28 years). Twenty-two patients had ischemia of the lower limb, and five patients had severe reflex sympathetic dystrophy. The retroperitoneal space was developed with a balloon trocar inserted through a small incision in the flank. Additional trocars used for endoscopic instruments. The sympathetic chain from the ganglia second lumbar vertebrae to the fourth lumbar vertebrae was resected. The procedure was successfully accomplished in all the patients without any operative or postoperative complications. The mean operative time Was 136 minutes, and the mean hospital stay was 1.4 days. All the patients had significant improvement of pain or dystrophic changes. Retroperitoneoscopic lumbar sympathectomy successfully combines the advantages of minimally invasive surgery with the effectiveness of the open procedure.  相似文献   
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Background  

Continuing medical education (CME) for general practitioners relies on specialist-based teaching methods in many settings. Formal lectures by specialists may not meet the learning needs of practitioners and may cause dissatisfaction with traditional CME. Increasing learner involvement in teaching programs may improve learner satisfaction.  相似文献   
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A major feature of ataxia-telangiectasia (A-T) is an increased risk of cancer, particularly of lymphoid malignancies. We studied ATM gene involvement in leukemic cells derived from 39 pediatric T-cell acute lymphoblastic leukemias (ALLs). Two types of sequence changes--truncating and missense--were identified in 8 T-cell ALL samples: 3 truncating changes, all previously identified in A-T (R35X, -30del215, 2284delCT), and 3 missense variants (V410A, F582L, F1463C) were found, none associated with loss of heterozygosity (LOH). In all patients studied, the mutation was present in the germ-line. A-T carriers, defined by the finding of truncating mutations, were found to be 12.9 times more frequent than in the normal population (P = 0.004). A normally ethnically matched population was screened for the 3 missense variants, and their frequency was significantly more prevalent (4.9-fold excess) than in the normal population (P = 0.03). Our data suggest there is some evidence of an association between missense alterations in the ATM gene and T-cell ALL. A significant difference in the mean age at diagnosis of T-cell ALL was noted between patients harboring an ATM sequence change and those with no change, 5.4 years and 9.7 years, respectively (P = 0.001). No ATM alterations were identified in relapse samples, indicating that ATM does not play a role in disease progression. The high prevalence of germ-line truncating and missense ATM gene alterations among children with sporadic T-cell ALL suggests an association with susceptibility to T-cell acute leukemia and supports the model of predisposition to cancer in A-T heterozygotes.  相似文献   
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Functional magnetic resonance imaging was used in combined functional selectivity and retinotopic mapping tests to reveal object-related visual areas in the human occpital lobe. Subjects were tested with right, left, up, or down hemivisual field stimuli which were composed of images of natural objects (faces, animals, man-made objects) or highly scrambled (1,024 elements) versions of the same images. In a similar fashion, the horizontal and vertical meridians were mapped to define the borders of these areas. Concurrently, the same cortical sites were tested for their sensitivity to image-scrambling by varying the number of scrambled picture fragments (from 16–1,024) while controlling for the Fourier power spectrum of the pictures and their order of presentation. Our results reveal a stagewise decrease in retinotopy and an increase in sensitivity to image-scrambling. Three main distinct foci were found in the human visual object recognition pathway (Ungerleider and Haxby [1994]: Curr Opin Neurobiol 4:157–165): 1) Retinotopic primary areas V1–3 did not exhibit significant reduction in activation to scrambled images. 2) Areas V4v (Sereno et al., [1995]: Science 268:889–893) and V3A (DeYoe et al., [1996]: Proc Natl Acad Sci USA 93:2382–2386; Tootell et al., [1997]: J Neurosci 71:7060–7078) manifested both retinotopy and decreased activation to highly scrambled images. 3) The essentially nonretinotopic lateral occipital complex (LO) (Malach et al., [1995]: Proc Natl Acad Sci USA 92:8135–8139; Tootell et al., [1996]: Trends Neurosci 19:481–489) exhibited the highest sensitivity to image scrambling, and appears to be homologous to macaque the infero-temporal (IT) cortex (Tanaka [1996]: Curr Opin Neurobiol 523–529). Breaking the images into 64, 256, or 1,024 randomly scrambled blocks reduced activation in LO voxels. However, many LO voxels remained significantly activated by mildly scrambled images (16 blocks). These results suggest the existence of object-fragment representation in LO. Hum. Brain Mapping 6:316–328, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
58.
Striatal dopa and glucose metabolism in PD patients with freezing of gait.   总被引:1,自引:0,他引:1  
In Parkinson's disease (PD), freezing suggests sudden and transient blocks of motor behavior during initiating or continuous repetitive movements. Its underlying pathophysiology remains unclear. The objective of this study is to compare striatal dopamine metabolism and cerebral glucose metabolism between PD patients with and without freezing of gait (FOG). A total of 10 PD patients with FOG at off and 7 PD patients without FOG underwent brain positron emission tomography with (18)[F]-6-fluoro-levodopa (FDOPA) and (18)[F]-fluordesoxyglucose (FDG). Striatum decarboxylase activity was expressed by metabolic influx constants of the striatum related to the occipital lobe (Kocc). FDG uptake in caudate and putamen was normalized to global FDG uptake. Region of interest (ROI) analysis of striatal regions was used, as well as voxel-based analysis by statistical parametric mapping (SPM). ROI analysis did not reveal differences in striatal FDOPA and FDG uptake between the groups. SPM showed lower putaminal FDOPA uptake (P = 0.05 uncorrected) with increased FDG uptake (P = 0.01 uncorrected) in freezing PD, whereas caudate uptake of the two tracers was reduced. Freezing-related cortical FDG decrease was found in (right) parietal regions. In conclusion, in freezing PD, caudate uptake of FDG and FDOPA was reduced, whereas putamen FDOPA decrease was associated with FDG increase. Right hemisphere circuitry seemed to be more affected in freezing patients.  相似文献   
59.
BACKGROUND: Interventional studies have shown that increased intake of fruit and vegetables reduces blood pressure (BP). However, the contribution of specific dietary components has not been evaluated. The aim of the present study was to determine, in patients with stage I hypertension, the antihypertensive effect of juice of the so-called sweetie fruit (a hybrid between grapefruit and pummelo) with and without high flavonoid content. METHODS: A double-blind, cross-over study was conducted in 12 patients. Each patient received alternately high-flavonoid (HF) sweetie juice and low-flavonoid (LF) sweetie juice, each for a 5-week period. The LF sweetie juice had 25% of naringin and 30% of narirutin content compared with the original HF sweetie juice. RESULTS: The HF sweetie juice was more effective than LF sweetie juice in reducing diastolic blood pressure (P = .04). Systolic blood pressure declined in both groups; however there was no significant difference between subjects given HF sweetie versus those given LF sweetie juice. CONCLUSIONS: In this study HF sweetie juice was shown to have a significant beneficial effect in reducing diastolic blood pressure, compared with the effect observed with LF sweetie juice, in patients with stage I hypertension. These data suggest that the active ingredients associated with the antihypertensive effect of sweetie juice are the flavonoids naringin and narirutin.  相似文献   
60.
The objective of the research was to determine the effect of the type, dose, and volume of anti-fibrinolytic agents (tranexamic acid, aprotinin) added to fibrin formulations, on adhesion development. Adhesions were induced in 228 male rats by creating apposing parietal and visceral peritoneal defects. Animals were randomized to receive no treatment or a fibrin formulation containing aprotinin or tranexamic acid. Seven days later the incidence of adhesions, and the force and energy required to detach them, were determined. Adhesions developed in 13/13 rats in the control and aprotinin groups. Treatment with fibrin (100 mg/ml tranexamic acid) resulted in adhesions in 4/14 rats (as strips, p < or = 0.0005), 4/10 rats (as spray, p < or = 0.0036), and 12/15 rats (by drip). The reduction of adhesions was dependent on the concentration of tranexamic acid with strip and spray application. Using commercial formulations, tranexamic-acid-containing fibrin (10/15, p = 0.042), but not aprotinin-containing fibrin (13/15), reduced the incidence of side-wall adhesions from 15/15 in controls. Fibrin containing either tranexamic or aprotinin reduced the incidence and severity of adhesions. This effect was greater when tranexamic acid was used and was dependent on the mode of administration, the volume, and to a degree, the concentration of tranexamic acid.  相似文献   
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