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991.
Metacarpal and phalangeal lengths were measured on 1290 hand radiographs of Nigerian children, aged 3–16 years. The radiographs were obtained during a combined cross-sectional and longitudinal study of growth and development. There is a linear increase in tubular bone length with age in both sexes. The girls have higher values for all the bones up to the age of 13 years when the boys overtake them. Comparison of our data with those from North American children shows that the values amongst Nigerian children are higher than White, Black American and Mexican American children. Of particular note is the difference between Black American and Nigerian figures. It is postulated that the decreased metacarpophalangeal lengths in Black Americans compared with Nigerians may be due to gene dilution.  相似文献   
992.
993.
Sclerosing bone dysplasias are a poorly understood group of developmental anomalies, much of whose etiology is still obscure. The list of conditions constituting this group is relatively short: osteopetrosis (Albers-Schönberg disease), pycnodysostosis (Maroteaux-Lamy disease), enostosis (bone island), osteopoikilosis, osteopathia striata (Voorhoeve disease), progressive diaphyseal dysplasia (Camurati-Engelmann disease), hereditary multiple diaphyseal sclerosis (Ribbing disease), four types of endosteal hyperostosis (van Buchem disease, Worth disease, Nakamura disease, and Truswell-Hansen disease), dysosteosclerosis, metaphyseal dysplasia (Pyle's disease), craniometaphyseal dysplasia, melorheostosis (Leri disease), and craniodiaphyseal dysplasia. There are instances in which two or more of the above disorders coexist. These are termed overlap syndromes, most commonly involving osteopathia striata, osteopoikilosis, and melorheostosis. A classification of these dysplasias is elaborated based on a target-site approach that views them as disturbances in development associated with the processes of either endochondral or intramembranous bone formation, or both. Accumulated evidence suggests that many of these disorders stem from common defects in bone resorption and/or formation during the processes of skeletal maturation and modeling. Finally, the subgroup of overlap syndromes is emphasized as indicating a strong interrelationship between the sclerosing dysplasias of bone, with perhaps a common pathogenesis for many.This article is one in a series of review articles which represent expansions of papers presented at the annual meeting of the International Skeletal Society and were solicited by the editors  相似文献   
994.
Experimental vascularized total joint autografts--a primate study   总被引:1,自引:0,他引:1  
Autogenous vascularized and nonvascularized total joint transfers were studied in the hands of Macaca fascicularis monkeys. Nine second toe proximal interphalangeal joints were transferred as a vascularized free graft to the hand, and the excised finger joints were transferred to the foot as a nonvascularized free graft. The grafts were examined clinically and histopathologically at 16 weeks to 10 months. Two of the nonvascularized free grafts were amputated because of infection and necrosis. Three had chronic infections. The four surviving nonvascularized grafts demonstrated necrosis of the hyaline cartilage and degenerative changes. Of the nine vascularized joints, one developed a wound infection that required amputation, another failed at 2 weeks because of wound dehiscence, and the remaining seven survived with preservation of the hyaline articular surfaces. The experimental technique was designed to be easily applied to clinical use. A skin island is provided as a "patency/viability monitor." The extensor mechanism is included in the graft for early function.  相似文献   
995.
Twenty-nine children (24, male; 5, female) with non-disseminated rhabdomyosarcomas of the bladder or prostate were treated (1978-1980) by a primary chemotherapy regimen consisting of vincristine, actinomycin D, and cyclophosphamide ("Pulse" VAC), with or without local radiotherapy. During the initial 20 wk of chemotherapy, nine children achieved a Clinical Complete Response (CCR). Three of these are without evidence of disease (NED) and have functional bladders, two following partial cystectomy. Four who achieved a CCR subsequently relapsed or remained biopsy positive, but are at present NED following radiotherapy and anterior exenteration. Two patients who achieved CCR status relapsed and have died of disease. Twelve patients had a Clinical Partial Response (CPR) in less than 20 wk and two others in less than 40 wk. Seven of these are NED with intact bladders following chemotherapy-radiotherapy; and an additional patient is NED following partial cystectomy. Four patients in the CPR group have been treated by exenteration following failure to achieve complete response, and are NED. One patient has died, and one has progressive disease. Six patients had an inadequate response to chemotherapy (NR). Anterior exenteration was carried out in three, and two of these have survived. The overall results in these 29 patients are: (A) alive and disease-free with functional bladders, 11; (B) alive and disease-free following anterior exenteration, 10; and (C) dead or death from tumor anticipated, 8. The function of retained bladders (11) has been satisfactory.  相似文献   
996.
The pattern of the focal bone lesion which consists partly or wholly of rounded holes with comparatively smooth edges is discussed.Twenty-two bone lesions were studied by angiography. The hypervascular pattern occurred in five cases of widely different histology, all with strong intraosseous hypervascularity. Different pathogenic mechanisms in the creation of this pattern are discussed. It is probably the result of both destructive and reparative processes in the bone.  相似文献   
997.
Since cell kinetic bone marrow studies have so far exclusively been carried out on aspiration material and have yielded inconsistent or even contradictory results, we investigated the adequacy and reliability of aspirates for cell kinetic analyses in comparison to biopsies. Paired samples of bone marrow (133) were taken simultaneously by aspiration and Jamshidi biopsy from 48 patients with acute leukemias and 67 patients with non-leukemic disorders. Cell kinetic analysis by (1) flow cytometry (FCM) of cellular DNA and RNA content, (2) autoradiography for [3H]TdR pulse labelling indices and (3) liquid scintillation counting of [3H]TdR uptake revealed significantly higher values in biopsies (p less than 0.001) exceeding the corresponding results from aspirates on average by factors of 1.65 for FCM S-phase index, 1.90 for G0/1 cells with high RNA content, 1.82 for [3H]TdR LI and 1.90 for [3H]TdR uptake. In more than 70% of all samples results from biopsies were 1.1-11.4 times higher, indicating that aspirates were equivalent to biopsies in fewer tan 30% of cases. Cell kinetic analysis in vitro blood/biopsy mixtures and measurements of DNA synthesis rate in corresponding aspirates and biopsies revealed that these discrepancies are due to the contamination of aspirates with non-proliferating nucleated blood cells. Biopsy, however, was found to provide representative and reproducible sampling of marrow for cell kinetic studies and should replace the presently used aspirate already characterized as "unreliable marrow juice" by Dameshek et al. in 1937 [18].  相似文献   
998.
Two newborn infants with duodenal and jejunal atresia and agenesis of the dorsal mesentery represent our surgical experience with "apple peel" small bowel or "christmas tree" demormity. The first patient had the typical appearance of this condition. The postoperative course was complicated by hyperbilirubinemia, septicemia, and disseminated intravascular coagulation. The infant is in satisfactory condition 1.5 years after operation. The second patient had agenesis of the dorsal mesentery without spiraling of the bowel around its vascular stalk. The child died after 1 month, with complete absence of extrahepatic bile ducts as seen at a second laparotomy. Neither child had been subjected to gastrostomy.  相似文献   
999.
Venous congestion in a replanted or transplanted digit can be detected, even before any obvious color changes, by the "throbbing" elicited by pinching the digit between the thumb and finger of the examiner until the skin blanches. Releasing the pressure slowly, a sensation of throbbing will be felt synchronous with the patient's pulse rate. The sign disappears when venous congestion is relieved or when swelling persists and increases enough to lessen the arterial inflow.  相似文献   
1000.
Zusammenfassung Es wird die funktionelle Morphologie des bisher wenig bekannten M. canalis ani beschrieben. Dieser Muskel liegt dem Sphincter ani internus auf und zieht längs durch die submuköse und subcutane Schicht des Analkanals. Es wird gezeigt, daß er ein Bestandteil des Kontinenzorgans ist und für den Verlauf anorectaler Erkrankungen bedeutsam ist.
The importance of the musculus canalis ani for continence and anorectal diseases
Summary The functional morphology of the M. canalis ani is described. Hitherto this muscle has not been studied in detail. The M. canalis ani is located inside of the M. sphincter ani internus and reaches through the spatium submucosum et subcutaneum of the analcanal. This muscle is part of a described organ of continence. Its importance in the course of anorectal disease is shown.
  相似文献   
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