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The gross, microscopic, and ultrastructural features of a mixed liver hamartoma occurring in a three month old infant are reported. The differentiation from two solid liver masses, focal nodular hyperplasia and liver cell adenoma is emphasized. Mesenchymal hamartomas, though usually cystic rather than solid masses, share the histologic feature of fibroductular tissue with mixed liver hamartomas and focal nodular hyperplasia. Only the mixed liver hamartoma has extremely broad fields of ductules and an embryonic type of hepatocyte at the ultrastructural level. These and other hepatic lesions show morphologic evidence of transformation of liver cells into biliary epithelial cells in association with vascular connective tissue.  相似文献   
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An autoradiographic method combined with a rosette technique was used to assess the bactericidal activity of individual control and inflammatory peritoneal macrophages (PM phi) in the presence or absence of expression of Fc receptor for IgG (FcR). There was a lack of FcR reactivity in a certain percentage of both categories of PM phi exposed to E. coli X43, a bacterium which is readily phagocytosed in the presence of specific antibody. Both rosetting and non-rosetting PM phi were capable of phagocytosing E. coli X43, but inflammatory PM phi showed a marked reduction in their capacity to ingest these bacteria compared with control PM phi. Once ingested the E. coli X43 were killed equally well by non-rosetting and rosetting control and inflammatory PM phi.  相似文献   
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Antibodies to an intercellular substance of epidermis and other stratified squamous epithelia demonstrable by immunofluorescent staining have been reported to occur in the sera of patients with pemphigus vulgaris. Using sera of patients with bullous pemphigoid, antibodies to a component of the basement zone of skin had been found by the same technique. In the present study these observations have been confirmed and extended. In addition to the above mentioned immunofluorescent staining reactions, another type of antibody directed to a cytoplasmic or perinuclear component of epidermal cells was found in a variety of pathologic sera. This observation points to the need for differentiating other skin-reactive antibodies from those found only in pemphigus. Guinea-pig lip sections appeared to be satisfactory for these studies. Mixed immunofluorescence was found to yield staining reactions identical to those observed by the indirect staining method, and gave titres the same as or lower than those obtained by the indirect staining procedure. Using the indirect method with guinea-pig lip sections it was found that eight of ten sera of patients with pemphigus contained intercellular antibodies while 102 control sera failed to yield reactions of this type. The titres of antibodies appeared to be proportional to the severity of the disease process. Sera of two out of three patients suffering from bullous pemphigoid yielded immunofluorescence staining of the basement zone while 109 controls were negative for this antibody.  相似文献   
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The purpose of this study was to compare the power and strength changes, of the quadriceps femoris muscle group, following 6 weeks of training. Twenty-seven moderately trained, female subjects were placed into three equated groups: electrical stimulation plus isokinetic exercise (ES + IE), isokinetic exercise (IE), and electrical stimulation (ES). A CybexQ I1 isokinetic dynamometer was used for testing the quadriceps ' power and strength output at the velocities of 0, 30, 100, and 180 O/ sec. The ES + IE and ES groups received faradic stimulation (progressive from 10- 20 mA) from a Multitone Multifaradic Unit (model F283, Multitone Electric Co., London, England). In addition, the ES + IE group performed isokinetic contractions concurrently with the faradic stimulation. Thigh circumference (TC) and time to peak tension (TPT) were also calculated during the pre-, mid-, and post-tests. Results indicated that a significant power increment was evident between the pre- and posttests and the pre- and mid-tests for the combined groups (p < 0.05). However, there were no significant power increases between the three separate groups at the four velocities. Significant power differences (P c 0.05) for the combined groups between the pre- and post-tests and the pre- and mid-tests at the isokinetic velocities of 30 and OO/sec were also identified. TPT and TC did not change significantly for any group over the 6-week training period. This study indicated that the combined effects of ES + IE, IE, and ES are potentially effective means of improving power and strength; however, data did not reveal one method of training as being significantly superior to another. J Orthop Sports Phys Ther 1986;8(5):260-268.  相似文献   
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Maternal and Child Health Journal - Hypertensive disorders of pregnancy have lifelong implications on maternal cardiovascular health. Breastfeeding has a variety of maternal benefits, including...  相似文献   
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PurposeThe purpose of this study was for an international panel of experts to establish consensus indications for distal rectus femoris surgery in children with cerebral palsy (CP) using a modified Delphi method.MethodsThe panel used a five-level Likert scale to record agreement or disagreement with 33 statements regarding distal rectus femoris surgery. The panel responded to statements regarding general characteristics, clinical indications, computerized gait data, intraoperative techniques and outcome measures. Consensus was defined as at least 80% of responses being in the highest or lowest two of the five Likert ratings, and general agreement as 60% to 79% falling into the highest or lowest two ratings. There was no agreement if neither threshold was reached.ResultsConsensus or general agreement was reached for 17 of 33 statements (52%). There was general consensus that distal rectus femoris surgery is better for stiff knee gait than is proximal rectus femoris release. There was no consensus about whether the results of distal rectus femoris release were comparable to those following distal rectus femoris transfer. Gross Motor Function Classification System (GMFCS) level was an important factor for the panel, with the best outcomes expected in children functioning at GMFCS levels I and II. The panel also reached consensus that they do distal rectus femoris surgery less frequently than earlier in their careers, in large part reflecting the narrowing of indications for this surgery over the last decade.ConclusionThis study can help paediatric orthopaedic surgeons optimize decision-making for, and outcomes of, distal rectus femoris surgery in children with CP.Level of evidenceV  相似文献   
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