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61.
Identifying patterns of fetal growth alteration benefits both the clinician and the researcher. Twenty-four measurements in three variable sets (anthropometric measures, organ weights, and long-bone measures from radiographs) were taken on fetuses both with and without pathological conditions that are suspected to result in growth alteration. In addition, radiographs of each case were examined for the presence or absence of ossification centers. Based on least-squares regressions of the normal group, we calculated standardized residuals for the affected group to identify patterns of growth alteration. A large sample of fetuses between 15 and 42 weeks of gestational age with a variety of pathological conditions is described and evaluated for growth alterations. Symmetric and asymmetric growth alteration was detected in a small part of the sample and was predominantly isolated to fetuses in the late third trimester. Although patterns of growth alteration have been suggested as a means for noninvasive diagnoses of syndromes (such as trisomy 21), no consistent patterns are discernible in the current group. The sample provides a unique opportunity to evaluate fetal growth in terms of the interaction between genetic and environmental influences. 相似文献
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A Hebra JD Walker EP Tagge JT Johnson E Hardee HB Othersen 《Canadian Metallurgical Quarterly》1998,64(12):1161-1164
Splenectomy is indicated in several hematological disorders and it can be particularly challenging in children with sickle cell disease, splenomegaly, and recurrent sequestration. Over the last 6 months, we have developed a new technique for laparoscopic splenectomy (LS) for hypersplenism and splenomegaly in five children with sickle cell disease. The average age of our patients was 6 years (range, 2-11), and the average weight was 18.7 kg (range, 13.2-30.1). On preoperative ultrasound, spleen size index ranged from 0.42 to 0.76. For the LS, four trochars were placed. One patient, who also underwent a laparoscopic cholecystectomy, had six trochars placed, two of which were used for both cholecystectomy and splenectomy. After laparoscopic mobilization of the spleen and hilar vascular stapling, a Steiner electromechanical morcellator was inserted through the 12-mm port to extract cores of splenic tissue until complete splenectomy was achieved. No patient required conversion to an open procedure or creation of a larger incision to remove the massively enlarged spleen. Operative time averaged 190 minutes; the combined LS and cholecystectomy took 245 minutes. Postoperative length of stay was <2 days for all patients. There were no complications, and no patient required postoperative transfusion. Based on these early findings, we conclude that intracorporeal coring of splenic tissue allows for safe and complete laparoscopic removal of very large spleens in small children. It provides expedient recovery and minimal postoperative pain and scarring. This new technique should enable surgeons to perform LS even in patients with massive splenomegaly, eliminating the need for large and cumbersome intracorporeal bags or the creation of additional incisions to remove the spleen. 相似文献
64.
M Tolnay A Probst AU Monsch HB Staehelin R Egensperger 《Canadian Metallurgical Quarterly》1998,96(3):225-227
Glanzmann's thrombasthenia is a rare inherited hematological disorder defined by deficiency or abnormality of the glycoprotein (GP) IIb-IIIa complex. Presenting symptoms are hemorrhagic events, mainly epistaxis, purpura, or menorrhagia. We describe the clinical course and management of a 14-year-old girl with Glanzmann's thrombasthenia and severe menorrhagia. Following treatment with 20 U of packed red blood cells, 37 U of platelets, 7 U of fresh frozen plasma, cryoprecipitate, intravenous estrogens, and methylergotrine maleate with no improvement, the uterine cavity was packed for 48 hr. This unusual procedure halted the bleeding and avoided the necessity for a hysterectomy. When treating acute menorrhagia in patients with Glanzmann's thrombasthenia, the physician should be familiar with the characteristics and all treatment modalities for this disorder. 相似文献
65.
The functional integrity of the neuromuscular synapse requires that sufficient numbers of acetylcholinesterase (AChE) molecules be localized on the specialized extracellular matrix between the nerve terminal and the post-synaptic membrane. Multiple interrelated levels of regulation are necessary to accomplish this complex task including the spatial and temporal restriction of AChE mRNA expression within the muscle fiber, local translation and assembly of AChE polypeptides, and focused accumulation of AChE molecules on the extracellular matrix. This is accomplished in part through the organization of other extracellular matrix molecules into a complex which further associates with acetylcholine receptors and their accompanying molecules. Finally, the mature neuromuscular junction contains molecules which can act as receptors for the attachment of AChE which in turn may allow for the turnover of this enzyme at the synapse. This brief review will focus mainly on contributions from our laboratory towards understanding the mechanisms involved in organizing AChE molecules at the neuromuscular synapse. 相似文献
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The role of the medial capsule and transverse metatarsal ligament in hallux valgus deformity including stability of the first metatarsophalangeal and adjacent joints was investigated in vitro. The three-dimensional positions of the proximal phalanx, first metatarsal, and second metatarsal before and after sectioning the medial capsule and metatarsal ligament were measured using a magnetic tracking system. Valgus deformity of the hallux increased with medial capsule sectioning an average of 22.3 degrees +/- 6 degrees. Valgus deformity of the hallux increased with medial capsule and metatarsal ligament sectioning an average of 27.4 degrees +/- 9.1 degrees. Valgus deformity of the hallux did not change significantly after sectioning the metatarsal ligament only. No significant changes were found in varus and eversion of the first metatarsal, in valgus of the second metatarsal, in the distance between first and second metatarsal heads after sectioning the medial capsule, or in the metatarsal ligament. This study shows the importance of the medial capsule in hallux valgus deformity. The transverse ligament did not contribute substantially to cause the deformity. 相似文献
68.
Huntingtin is the protein product of the gene for Huntington's disease (HD) and carries a polyglutamine repeat that is expanded in HD (>36 units). Huntingtin-associated protein (HAP1) is a neuronal protein and binds to huntingtin in association with the polyglutamine repeat. Like huntingtin, HAP1 has been found to be a cytoplasmic protein associated with membranous organelles, suggesting the existence of a protein complex including HAP1, huntingtin, and other proteins. Using the yeast two-hybrid system, we found that HAP1 also binds to dynactin P150(Glued) (P150), an accessory protein for cytoplasmic dynein that participates in microtubule-dependent retrograde transport of membranous organelles. An in vitro binding assay showed that both huntingtin and P150 selectively bound to a glutathione transferase (GST)-HAP1 fusion protein. An immunoprecipitation assay demonstrated that P150 and huntingtin coprecipitated with HAP1 from rat brain cytosol. Western blot analysis revealed that HAP1 was enriched in rat brain microtubules and comigrated with P150 and huntingtin in sucrose gradients. Immunofluorescence showed that transfected HAP1 colocalized with P150 and huntingtin in human embryonic kidney (HEK) 293 cells. We propose that HAP1, P150, and huntingtin are present in a protein complex that may participate in dynein-dynactin-associated intracellular transport. 相似文献
69.
HB Peterson 《Canadian Metallurgical Quarterly》1998,279(20):1651-1658
70.
The results of 26 ankle arthrodeses performed for rheumatoid arthritis on 21 patients were reviewed. Tibiotalar arthrodesis was performed in 14 ankles, and tibiotalocalcaneal arthrodesis was performed in 12. External fixation was used in 20 ankles, and internal fixation was used in six. Followup was available in 24 of 26 ankles (19 patients), and averaged 5 years (range, 2-8 years). There was no pain experienced in 19 ankles; mild, occasional pain was experienced in four ankles; and moderate, daily pain was experienced in one ankle. Daily activities were limited in five patients and recreational activities were limited in 11. All patients reported some difficulty walking on uneven terrain. Nearly all patients were satisfied; two were satisfied with reservations and two were dissatisfied. Union was achieved in 25 of 26 (96%) ankles. Ankle arthrodesis is an effective operation in patients with rheumatoid arthritis. Unlike previous reports, union and complication rates in this series were comparable with rates for arthrodesis for posttraumatic and degenerative arthritis. 相似文献