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91.
OBJECTIVE: To study the utility and functional benefits of an implanted functional electrical stimulation (FES) system for hand grasp and release in adolescents with tetraplegia secondary to spinal cord injuries. DESIGN: Intervention study with before-after trial measurement with each subject as his or her own control. SETTING: Nonprofit pediatric orthopedic rehabilitation facility specializing in spinal cord injury. PARTICIPANTS: A convenience sample of five adolescents between 16 and 18 years of age with C5 or C6 level tetraplegia at least 1 year after traumatic spinal cord injury. Key muscles for palmar and lateral grasp and release were excitable by electrical stimulation. INTERVENTIONS: A multichannel stimulator/receiver and eight electrodes were surgically implanted to provide stimulated palmar and lateral grasp and release. In conjunction with implantation of the FES hand system, surgical reconstruction in the form of tendon transfers, tendon lengthenings and releases, and joint arthrodeses was performed to augment stimulated hand function. Rehabilitation of the tendon transfers and training in the use of the FES hand system were provided. MAIN OUTCOME MEASURES: Measurements of pinch and grasp force, the Grasp and Release Test (GRT), and an assessment of six activities of daily living (ADL) were administered before implantation of the FES hand system and at regular follow-up intervals. Results of the stimulated response of individual muscles and surgical reconstruction were evaluated using standard and stimulated muscle testing techniques and standard assessment of joint range of motion. All subjects completed followup testing. RESULTS: Lateral and palmar forces were significantly greater than baseline forces (p = .043). Heavy objects on the GRT could only be manipulated with FES, and FES increased the level of independence in 25 of 30 ADL comparisons (5 subjects, 6 activities) as compared to baseline. After training, FES was preferred in 21 of 30 comparisons over the typical means of task completion. Of the 40 electrodes implanted, 37 continue to provide excellent stimulated responses and all of the implanted stimulators have functioned without problems. The surgical reconstruction procedures greatly enhanced FES hand function by either expanding the workspace in which to utilize FES (deltoid to triceps transfer), stabilizing the wrist (brachioradialis to wrist extensor transfer), or stabilizing joints (intrinsic tenodesis transfer, FPL split transfer). CONCLUSION: For five adolescents with tetraplegia, the combination of FES and surgical reconstruction provided active palmar and lateral grasp and release. Laboratory-based assessments demonstrated that the FES system increased pinch force, improved the manipulation of objects, and typically increased independence in six standard ADL as compared to pre-FES hand function. The study also showed that the five adolescents generally preferred FES for most of the ADL tested. Data on the benefits of the implanted FES hand system outside of the laboratory are needed to understand the full potential of FES. 相似文献
92.
We present a new background-subtraction technique fusing contours from thermal and visible imagery for persistent object detection in urban settings. Statistical background-subtraction in the thermal domain is used to identify the initial regions-of-interest. Color and intensity information are used within these areas to obtain the corresponding regions-of-interest in the visible domain. Within each region, input and background gradient information are combined to form a Contour Saliency Map. The binary contour fragments, obtained from corresponding Contour Saliency Maps, are then fused into a single image. An A* path-constrained search along watershed boundaries of the regions-of-interest is used to complete and close any broken segments in the fused contour image. Lastly, the contour image is flood-filled to produce silhouettes. Results of our approach are evaluated quantitatively and compared with other low- and high-level fusion techniques using manually segmented data. 相似文献
93.
I Sylvester AF Suffredini AJ Boujoukos GD Martich RL Danner T Yoshimura EJ Leonard 《Canadian Metallurgical Quarterly》1993,151(6):3292-3298
We recently found that normal human sera contain IgG antibodies against two chemoattractants, neutrophil attractant protein-1 (NAP-1/IL-8) and monocyte chemoattractant protein-1 (MCP-1), as well as immune complexes of these proteins. Intravenously administered LPS was reported to cause a sharp rise in serum NAP-1 concentration. Our study was designed to determine if LPS also caused an increase in MCP-1 and to measure associated changes in concentrations of antibody and immune complex. LPS caused a rise to peak within 2 to 3 h in serum concentrations of free NAP-1 and MCP-1, followed by an almost equally rapid fall toward base-line levels by about 5 h postinjection. MCP-1 concentration in sera from the 11 subjects rose to a peak of 330 +/- 52 pM. The peak value for NAP-1 was 80 +/- 11 pM. In 10 of the 11 subjects, free IgG autoantibody to MCP-1 decreased from a mean pre-LPS value of 1820 +/- 660 pM to a mean low of 53% of the respective initial values. Corresponding data for IgG anti-NAP-1 were a pre-LPS concentration of 216 +/- 7 pM, which decreased to a mean low of 44% of the respective initial values. The finding in some subjects of a rapid rise in free antibody after the nadir suggests the possibility of acute regulation of autoantibody secretion rates. Although the results suggested that LPS-induced chemoattractant combined with free antibody, serum concentrations of MCP-1-IgG or NAP-1-IgG did not increase, which points to an as yet unknown mechanism for trapping and elimination of the immune complexes. 相似文献
94.
This issue begins the journal's second year as an APA divisional journal. In this column, the editor presents a brief review of the history of the division, and discusses trends, or shifts, in the division's focus. Prior to 1972, the first phase saw the development of rudimentary theories of consultation emerging in the clinical, educational, and business fields. In the second phase, consultation theories were elaborated and tuned to specific application areas. Competition and some hostility developed between these groups which limited cooperation and collaboration. In the emerging third phase, the editor expects increased respect, cooperation and collaboration to emerge as the next generation of consultants become influential. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
We conducted a review to investigate the prevalence of human immunodeficiency virus (HIV), or acquired immunodeficiency syndrome (AIDS), in patients with herpes zoster ophthalmicus, as well as the incidence of acute retinal necrosis after herpes zoster ophthalmicus. All charts of patients seen at our institution between 1987 and 1992 with a primary diagnosis of herpes zoster ophthalmicus were reviewed. Of 112 patients with herpes zoster ophthalmicus, 29 (26%) had HIV or AIDS. All these patients were younger than 50 years at the time of diagnosis. Five of 29 (17%) immunocompromised patients had acute retinal necrosis after herpes zoster ophthalmicus. No acute retinal necrosis was identified in the nonimmunocompromised patients after herpes zoster ophthalmicus. We recommend that all patients younger than 50 years who have herpes zoster ophthalmicus at initial examination be tested for HIV. Additionally, HIV-infected patients should be monitored closely after herpes zoster ophthalmicus for development of acute retinal necrosis. Long-term oral prophylactic as well as initial high-dose intravenous acyclovir may be appropriate in HIV-infected individuals with herpes zoster. 相似文献
96.
97.
RJ Mayer RB Davis CA Schiffer DT Berg BL Powell P Schulman GA Omura JO Moore OR McIntyre E Frei 《Canadian Metallurgical Quarterly》1994,331(14):896-903
BACKGROUND: About 65 percent of previously untreated adults with primary acute myeloid leukemia (AML) enter complete remission when treated with cytarabine and an anthracycline. However, such responses are rarely durable when conventional postremission therapy is administered. Uncontrolled trials have suggested that intensive postremission therapy may prolong these complete remissions. METHODS: We treated 1088 adults with newly diagnosed AML with three days of daunorubicin and seven days of cytarabine and randomly assigned patients who had a complete remission to receive four courses of cytarabine at one of three doses: 100 mg per square meter of body-surface area per day for five days by continuous infusion, 400 mg per square meter per day for five days by continuous infusion, or 3 g per square meter in a 3-hour infusion every 12 hours (twice daily) on days 1, 3, and 5. All patients then received four courses of monthly maintenance treatment. RESULTS: Of the 693 patients who had a complete remission, 596 were randomly assigned to receive postremission cytarabine. After a median follow-up of 52 months, the disease-free survival rates in the three treatment groups were significantly different (P = 0.003). Relative to the 100-mg group, the hazard ratios were 0.67 for the 3-g group (95 percent confidence interval, 0.53 to 0.86) and 0.75 for the 400-mg group (95 percent confidence interval, 0.60 to 0.94). The probability of remaining in continuous complete remission after four years for patients 60 years of age or younger was 24 percent in the 100-mg group, 29 percent in the 400-mg group, and 44 percent in the 3-g group (P = 0.002). In contrast, for patients older than 60, the probability of remaining disease-free after four years was 16 percent or less in each of the three postremission cytarabine groups. CONCLUSIONS: These data support the concept of a dose-response effect for cytarabine in patients with AML who are 60 years of age or younger. The results with the high-dose schedule in this age group are comparable to those reported in similar patients who have undergone allogeneic bone marrow transplantation during a first remission. 相似文献
98.
Classroom Presenter is a Tablet PC-based interaction system that supports the sharing of digital ink on slides between instructors and students. Initial deployments show that using the technology can achieve a wide range of educational goals and foster a more participatory classroom environment. 相似文献
99.
An overview of the most important older and newer results regarding the relationship between violent and criminal behavior on the one hand and schizophrenic illness on the other hand is presented. Four different methods are available to study this relationship: (i) study of the prevalence of mental illness in criminal/violent populations; (ii) study of criminality/violence rate in samples of psychiatric patients; (iii) study of criminality/violence in community samples comparing mental patients with non-patient community residents; and (iv) study of criminality/violence in birth cohorts prospectively. All these methods have been used; but samples composed of schizophrenic patients exclusively were only exceptionally studied. The results indicate that there is a modest but significant relationship between schizophrenia and violence and crime which persists even after controlling for demographic and socio-economic variables. The probability of schizophrenic patients to be criminal or violent depends on the acuity of their illness and is increased by their use of psychoactive substances. Generally, however, violent and criminal acts directly attributable to mental illness account only for a very small proportion of such acts in the society. 相似文献
100.
Male and female mice of the BALB/c strain were placed on the floor of a hut built at a site of the Permian Basin of Lodève (Southwest France) where the dose rate of γ radiation amounts to about 10 mrad/h. In previous experiments such high natural radioactivity was shown to induce point mutations in plant material as well as chromosome aberrations in somatic cells of experimental mammals. Controls were kept near the radioactive site under comparable conditions. After the exposure period, the animals were mated in our laboratory, with control mice of the same strain.Due to the high radiosensitivity of mouse oocytes, the fertility of the exposed females was drastically reduced in spite of the fact that the dose received did not exceed 13.8 rad. The fertility of the males exposed to 13 rad, 15 rad or to 45 rad was increased above the control values but was reduced for the animals receiving 63 rad. Analysis of the results show that the differences in fertility are mainly due to a decrease in the number of sterile pairs when males have been exposed to doses upto 45 rad and to an inverse effect when animals received 63 rad. Since histology and weight of the testes suggest that the germ cell population was normal, one has to conclude that the variations in fertility result from physiological effects. 相似文献