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991.
RB Duckrow 《Canadian Metallurgical Quarterly》1993,618(2):190-195
A retrospective analysis was done of the records and radiographs of 100 club feet (in sixty-six patients) that had been consecutively treated with an operation. Twenty-six feet (26 per cent) had had a Grade-II deformity of the calcaneocuboid joint, as determined with a radiographic classification that had been developed on the basis of the degree of medial displacement of the cuboid. When the calcaneocuboid joint is in normal alignment, the central point of the cuboid ossification center lies on the mid-longitudinal axis of the calcaneus; when there is a Grade-I deformity, the mid-point of the cuboid ossification center lies lateral to the medial tangent but medial to the longitudinal axis of the calcaneus; and when there is a Grade-II deformity, the central point of the cuboid lies on or medial to the medial tangent of the calcaneus. Although a Grade-I deformity of the calcaneocuboid joint need not be corrected, a Grade-II deformity should be treated with release of the calcaneocuboid joint, which in this series was performed in conjunction with a complete subtalar release (including a talonavicular release). Sixteen of the twenty-six feet that had a Grade-II deformity had a complete release of the calcaneocuboid joint at the time of the operation; the release was not done in the remaining ten feet, some of which were operated on early in the series, before the importance of the deformity at the calcaneocuboid joint had been recognized.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
992.
993.
OBJECTIVE: Granuloma annulare is an uncommon benign inflammatory dermatosis characterized by the formation of dermal papules with a tendency to form rings. There are several clinically distinct forms. The subcutaneous form is the most frequently encountered by radiologists, with the lesion presenting as a superficial mass. There are only a few scattered reports of the imaging appearance of this entity in the literature. We report the radiologic appearance of five cases of subcutaneous granuloma annulare. DESIGN AND PATIENTS: The radiologic images of five patients (three male, two female) with subcutaneous granuloma annulare were retrospectively studied. Mean patient age was 6.4 years (range, 2-13 years). The lesions occurred in the lower leg (two), foot, forearm, and hand. MR images were available for all lesions, gadolinium-enhanced imaging in three cases, radiographs in four, and bone scintigraphy in one. RESULTS: Radiographs showed unmineralized nodular masses localized to the subcutaneous adipose tissue. The size range, in greatest dimension on imaging studies, was 1-4 cm. MR images show a mass with relatively decreased signal intensity on all pulse sequences, with variable but generally relatively well defined margins. There was extensive diffuse enhancement following gadolinium administration. CONCLUSION: The radiologic appearance of subcutaneous granuloma annulare is characteristic, typically demonstrating a nodular soft-tissue mass involving the subcutaneous adipose tissue. MR images show a mass with relatively decreased signal intensity on all pulse sequences and variable but generally well defined margins. There is extensive diffuse enhancement following gadolinium administration. Radiographs show a soft-tissue mass or soft-tissue swelling without evidence of bone involvement or mineralization. This radiologic appearance in a young individual is highly suggestive of subcutaneous granuloma annulare. 相似文献
994.
Visually guided, goal-directed reaching requires encoding action distance and direction from attributes of visual landmarks. We identified a cognitive mechanism that seemingly performs visual motor extension before action initiation and replicated and extended previous results that identified a mechanism for visual motor mental rotation. We find that humans systematically delay action onset while newly planning increasingly distant arm movements beyond a visual landmark, consistent with an internal representation for visual motor extension. Onset times also changed systematically during concurrent mental rotation and visual motor extension computations required to process new directions and distances. Visual motor extension associated with reaching slowed when participants needed to plan action direction within the same time frame, whereas mental rotation efficiency was unaffected by concurrent needs to prepare action distance. In contrast to parallel direction and distance computations needed for direct aiming to a visual target, the planning of new directions and distances likely occurs at distinct times. When considered with previous findings, the current results suggest the existence of an intermediate component of motor preparation that engages a covert mechanism of cognitive motor planning. 相似文献
995.
996.
RV Durvasula A Gumbs A Panackal O Kruglov S Aksoy RB Merrifield FF Richards CB Beard 《Canadian Metallurgical Quarterly》1997,94(7):3274-3278
Expression of molecules with antiparasitic activity by genetically transformed symbiotic bacteria of disease-transmitting insects may serve as a powerful approach to control certain arthropod-borne diseases. The endosymbiont of the Chagas disease vector, Rhodnius prolixus, has been transformed to express cecropin A, a peptide lethal to the parasite, Trypanosoma cruzi. In insects carrying the transformed bacteria, cecropin A expression results in elimination or reduction in number of T. cruzi. A method has been devised to spread the transgenic bacteria to populations of R. prolixus, in a manner that mimics their natural coprophagous route of symbiont acquisition. 相似文献
997.
RH Meloen JA Turkstra H Lankhof WC Puijk WM Schaaper G Dijkstra CJ Wensing RB Oonk 《Canadian Metallurgical Quarterly》1994,12(8):741-746
BACKGROUND: DTIC and interleukin-2 (IL-2), as single agents, have a limited anti-tumor activity in patients with metastatic melanoma. Experimentally, thymosin alpha 1 (TA1) may modulate the action of IL-2. We investigated the clinical and immunological effects of a combination with these three agents. PATIENTS AND METHODS: Forty-six patients with measurable metastatic melanoma were treated with DTIC 850 mg IV on day 1, TA1 2 mg s.c. on days 4 to 7, and IL-2 18 MU/m2/d by continuous intravenous infusion on days 8 to 12. Cycles were repeated every 3 weeks. RESULTS: Objective responses were obtained in 15 (36%) of 42 evaluable patients (CI at 95%: 22%-50%). Two patients experienced complete responses, and stable disease was observed in five. The median time to progression was 5.5 months and median survival was 11 months. Side effects were predominantly caused by IL-2. Treatment was tolerated reasonably well, and there was no overlapping toxicity or interference between chemotherapy and biotherapy. Baseline sCD4 levels seem to correlate to tumor burden. Patients benefiting from treatment had lower sCD4 and higher sCD8 than did progressing patients. CONCLUSIONS: The combination of DTIC + TA1 + IL-2 is active in the treatment of advanced melanoma, with acceptable toxicity. However, even more active regimens are needed, and the interactions between thymic hormones and cytokines should be further explored. 相似文献
998.
DA Bennett L Phun JF Polk SA Voglino V Zlotnik RB Raffa 《Canadian Metallurgical Quarterly》1998,32(11):1201-1208
OBJECTIVE: A developmental-ecological model was used to explore the psychological adjustment and peer social competencies of maltreated preschool children. METHOD: Enhanced research methods were used that included verification of maltreatment status, multiple-variable matching of comparison children, and contextually relevant assessment. One hundred eight Head Start children, of whom 54 were maltreated, participated. Assessment of social functioning included measurement of peer play interactions, global social skills, peer sociometrics, and teacher and parent ratings of behavior problems. RESULTS: Findings indicated that maltreated children were significantly less interactive in peer play and overall exhibited less self-control and interpersonal skill in social interactions than nonmaltreated children. In addition, maltreated children were more likely than their nonmaltreated peers to receive low sociometric ratings and were found by both teachers and parents to display more internalizing behavior problems than comparison children. CONCLUSIONS: These findings indicate the importance of using developmentally sensitive research methods to inform contextually relevant interventions. 相似文献
999.