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91.
In order to test whether peripheral input from a moving forelimb is essential for reaching in rats, the effects of dorsal rhizotomy C5-Th2 were examined. Rats were trained to reach for a food pellet in the horizontal tube or on a tray. Reaching attempts before and after bilateral forelimb deafferentation were monitored by continual recording using magnetic induction. Deafferented animals were able to initiate and generate the motor program of reaching, but modulation of its ongoing execution was lost. Peripheral input from moving forelimb was necessary for the effective performance of grasping; the duration of the manipulative part of reaching was significantly prolonged and the success of grasping was markedly decreased. Also, the aiming of forelimb was impaired, probably by disturbing of body forelimb postural coordination. No significant changes were found in the execution of forelimb protraction. It is concluded that somesthetic feedback is not required for execution of forelimb protraction, but it is necessary for grasping. 相似文献
92.
Subtraction and conventional radiography were evaluated for their diagnostic potential to assess interradicular bone lesions in the mandibular premolar region. Both conventional radiographs and subtraction images were interpreted by 10 observers. The receiver-operating characteristic (ROC) technique was used to compare the two techniques. The diagnostic validity was higher for the subtraction technique, both for lesions confined to cancellous bone and for lesions including the cortical bone, than for the conventional technique. For bone defects confined to cancellous bone the diagnostic accuracy was lower than those reported from periapical bone lesions irrespective of whether subtraction or conventional radiography was used. We conclude that subtraction radiography improves the detectability of bone lesions, shallow ones in particular. Lesions in the interradicular bone are more difficult to detect than those in the periapical bone. 相似文献
93.
K Hejlícek I Literák B Chalupa 《Ceskoslovenská epidemiologie, mikrobiologie, imunologie》1992,42(3):135-140
In 1980-1990 in the Strakonice district parallel serological examinations, using the Sabin-Feldman test (SFT) and complement fixation test (CFT), were made in 2,758 blood donors for the presence of antibodies against toxoplasmosis. The total number of examinations was 8,245. In the course of the mentioned time interval no significant increase or decrease of the serological prevalence occurred. During the first examination of blood donors the SFR antibodies (titre > or = 4) were detected in 45.4%, CFT (titre > or = 10) in 24.6% donors. 651 blood donors were examined four times or more frequently after 6-month intervals. 22.9% donors lacked antibodies (SFT and CFT) permanently, a rarely present low titre was recorded in another 22.9% donors, a repeated low titre in 43.6% and a repeatedly encountered medium or high titre in 10.6% of blood donors. 相似文献
94.
T L Tammela P A Hellstr?m S I Mattila P J Ottelin L J Malinen H P M?k?r?inen 《The Journal of urology》1992,147(6):1551-1553
Sclerotherapy with 5% ethanolamine oleate was used to treat 102 hydroceles in 100 patients and 63 spermatoceles in 58 patients. Scrotal ultrasound examination was performed before the sclerotherapy and at each followup visit. Of the hydroceles 98% were cured completely and 68% were cured after only 1 sclerosant instillation, while 60% of the spermatoceles resolved completely and 33% partially, with 7% failures. No hydroceles recurred during an average followup of 43 months, whereas spermatocele recurred in 4 patients more than 1 year after successful treatment, with a mean followup of 46 months. Approximately half of the patients experienced pain after treatment, 3 had infection and 2 had hematoma. No changes in the structure or size of the testicles were found by ultrasound during followup. Ethanolamine oleate sclerotherapy is a safe, effective and economical form of outpatient therapy that can be recommended as primary treatment for hydroceles in adults and as an alternative to surgery for spermatoceles with 1 to 3 cysts in elderly men in whom fertility is not important. 相似文献
95.
96.
Summary The effects of acute arterial subdural bleeding on cerebrospinal fluid (CSF) pressure and 12 other vital parameters were studied in spontaneously breathing pigs (group 1, n=9) and in mechanically ventilated pigs (group 2, n=18) to analyze quantitatively the bleeding course and the lethal mechanism.Spontaneously breathing animals all succumbed after a mean bleeding volume of 45.6±8.9ml, corresponding to about 50 per cent of the intracranial volume, and a mean bleeding duration of 11.0±2.6 min. Rapid rise in CSF pressures, marked transtentorial pressure gradients, and progressive reductions of cerebral perfusion pressure leading to a permanently iso-electric EEG, apnoea and to a terminal rise in arterial pressure (Cushing response), was the rule in these animals.The mechanically ventilated animals had smaller bleeding volumes (34.3±8.1 ml), but longer bleeding durations (13.8±5.8 min). In this group 7 animals survived. They had no pressure gradients, and only moderate changes in arterial pressure and EEG. The 11 animals that succumbed had marked transtentorial pressure gradients, but smaller increments in arterial pressure than the spontaneously breathing animals.At autopsy, subdurally located blood was found throughout the intracranial and spinal subdural compartments and along the spinal nerve roots in both groups.The results of this study suggest that survival after acute subdural haematoma is influenced by the presence of transtentorial pressure gradients and by the spinal sac acting as a space for expansion. The beneficial effect of artificial ventilation is discussed.This study has been supported by the University of Oslo, The Anders Jahre Foundation for The Advance of Research, and by the Norwegian Society for fighting Cancer. 相似文献
97.
We investigated the effects of polymerization heat and toxicity of polymethyimetacrylate bone cement in the canine tibial diaphysis. Heat was studied by filling the tibias with either bone cement or bone wax contained in a monomer tight membrane pouch. Toxicity was studied by filling both tibias with cement, with the control side contained in the membrane pouch. Bone blood perfusion was measured by microsphere technic, and bone remodeling by 99mTc-methylene diphosphonate uptake and by histologic technique. In bone exposed to the combination of polymerization heat and monomer, both perfusion and remodeling were impaired. We did not find any effects of polymerization heat alone.
We conclude that hot toxic chemicals from bone cement during polymerization may inhibit bone blood perfusion and remodeling, whereas heat alone seems to be of minor importance for the regenerative processes in cemented diaphyseal bone. 相似文献
We conclude that hot toxic chemicals from bone cement during polymerization may inhibit bone blood perfusion and remodeling, whereas heat alone seems to be of minor importance for the regenerative processes in cemented diaphyseal bone. 相似文献
98.
S. Lundgren S. Gundersen R. Klepp P. E. Lønning E. Lund S. Kvinnsland 《Breast cancer research and treatment》1989,14(2):201-206
In this prospective, randomized study the clinical response and toxicity of megestrol acetate (MA) and aminoglutethimide (AG) as second-line treatment in patients with metastatic breast cancer was compared. 176 patients were included, and 150 received treatment greater than 8 weeks and are evaluable for treatment response. The two groups did not differ with regard to prognostic factors. Response rate for the AG and MA groups were 34% and 31% respectively, with duration of response of 13.1 and 13.0 months. Stable disease was obtained in 33% and 35% respectively. No difference was observed in survival. Side effects occurred more frequently in the AG group (42%) than in the MA group (18%). 相似文献
99.
Lise Pedersen Susanne Holck Torben Schiødt Karin Zedeler Henning T. Mouridsen 《Breast cancer research and treatment》1989,14(1):91-99
Summary One hundred thirty-one breast carcinomas with medullary features, registered in the Danish Breast Cancer Cooperative Group from 1977–1982, have been histopathologically reviewed by two senior pathologists and classified as typical medullary carcinoma (TMC), atypical medullary carcinoma (AMC), and non-medullary carcinoma (NMC). Diagnostic criteria were based on those put forward by Ridolfiet al. and Fisheret al. The procedure was repeated with an interval of about one year by both pathologists. The diagnostic interobserver agreement was 72% with a Kappa of 0.55. The intraobserver agreement was 77% and 63% with Kappa values of 0.64 and 0.44, respectively. To see whether the observed inter- and intraobserver variability had any prognostic implications, diagnostic subgroups for both pathologists were analyzed with Kaplan Meier plots for recurrence-free survival (RFS) and with log rank tests. In the first evaluation pathologist 1 segregated a group of TMC with a significantly better RFS than for the NMC group, and pathologist 2 segregated a group of TMC with a corresponding strong trend. These findings could not, however, be reproduced in the second evaluation. The study indicates that the criteria of TMC and AMC as proposed by Ridolfiet al. need to be sharpened and simplified in order to reduce inter-and intraobserver variability. Larger studies with a control group of infiltrating ductal carcinomas are mandatory to elucidate the clinical importance of the diagnoses of Typical and Atypical Medullary Carcinoma of the breast. 相似文献
100.
We report the cases of five patients with lesions of benign reactive hyperplasia of the skin in the hip joint region. In view of the distinct clinical features, and in analogy with previously reported cases of acanthoma fissuratum, we termed this condition acanthoma supratrochantericum. 相似文献