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131.
Multiple trauma is often associated with blunt thoracic injuries. Especially lung contusion can result in respiratory insufficiency and therefore a higher mortality rate. In our prospective study comparing 8 multiple trauma patients with and without associated lung contusion, we found that respiratory function was already significantly disturbed (decrease of paO2/FiO2 and increase of AaDO2, a rise in extravascular lung water (EVLW) both early after trauma and also with a second peak following the 4th day. This group (LK) developed significantly more cases of respiratory distress (ARDS). The disturbance of respiratory function seen initially was interpreted as a consequence of the direct mechanical impact, leading to the formation of interstitial fluid and hematoma. The frequent development of ARDS in the LK-group probably results from a pronounced activation of cellular and humoral mechanisms and therefore an enforced injury of the pulmonary capillary bed. A significant increase of pulmonary infections or the development of sepsis was not seen in the LK-group and is probably not responsible for the higher ARDS-rate in this group.  相似文献   
132.
The skeletal manifestations of malignant carcinoid seem not to have been reported in the orthopedic literature. Bronchial and hindgut carcinoid tumors are less numerous than midgut tumors but metastasize to bone much more frequently. Carcinoid skeletal deposits are usually osteoblastic and most commonly affect the axial skeleton. The radiologic appearance is frequently indistinguishable from prostatic skeletal metastases or chronic sclerosing osteomyelitis. Two cases of skeletal metastases from midgut carcinoid are reported to demonstrate that metastases from carcinoid should be considered in the differential diagnosis of either bone malignancy or chronic sclerosing osteomyelitis.  相似文献   
133.
The influence of the pore size of Nucleopore diffusion-chamber filters on the rate of proliferation and differentiation of periosteal cells in muscle was studied in 44 growing rabbits. Periosteal grafts were placed in chambers (16-19 in each experimental group) sealed with filters with a pore size of 0.4, 0.6, 0.8, 1.0, or 2.0 micron. Each chamber was implanted into the paraspinal muscle of the rabbit, where it remained for 16 weeks. The osteochondrogenic activity of the graft grew linearly when the pore size increased from 0.4 to 1.0 micron. In the chambers with a pore size of 2.0 micron, both bone and cartilage were found in only one chamber. Bone and cartilage were not found outside any of the chambers. The present results showed that the pore size of the filters significantly affected the ability of the periosteal graft to form bone and cartilage.  相似文献   
134.
The effects of bulk versus particulate polymethylmethacrylate on bone   总被引:3,自引:0,他引:3  
Twenty-one mature New Zealand white female rabbits were allocated into three groups of seven rabbits. Group I received a bolus of doughy Simplex polymethylmethacrylate (PMMA) cement injected into the proximal tibia through a drill hole. Group II received a preformed, cooled, bulk PMMA pellet. Group III had particulate PMMA powder implanted. The operated, but nonimplanted, left tibiae served as controls. Animals were killed after four months. Histologically, both Group I and Group II demonstrated a thin, fibrous tissue membrane at the implant interface. Particulate PMMA (Group III) stimulated a much thicker, florid, foreign body reaction composed of histiocytes and giant cells. The foreign body response to particulate acrylic cement was similar to that seen in failed cemented joint replacement arthroplasty in humans.  相似文献   
135.
Computed tomography (CT) is currently the imaging modality of choice for assessing the morphology of the adrenal glands in adult patients. Much useful information can be gained using CT in disease processes which primarily involve one or both of the adrenal glands, such as adenomas, as well as in entities which secondarily affect the adrenals, such as pituitary or metastatic disease. The size and configuration of the glands can be readily determined, and masses may be detected. We discuss CT of normal and abnormal adrenal glands with sonographic (US) and pathological correlation, when available. Entities which may mimic adrenal abnormalities are emphasized. Relative advantages of US over CT in the pediatric patient are discussed.  相似文献   
136.
J Arton 《Nursing times》1988,84(14):96-98
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137.
The Dundee Memory Clinic was established in 1991. This paper reviews the diagnosis of the first 150 attenders and compares the findings with those of other memory clinics.  相似文献   
138.
139.
Fibroblasts incorporated within collagen gels induce a cell-mediated contraction of the gel to form a three-dimensional, tissue-like structure by a mechanism thought to mimic wound contraction in vivo . In this study a gel contraction model was used to investigate the ability of fibroblasts derived from adult gingiva, adult skin and fetal skin to organise a collagen matrix. In addition the effects of interleukin-1β (IL-1β) on the contraction process was also investigated. Over the concentration range 5-50 U/ml, IL-1β induced a statistically significant inhibition of gel contraction in all fibroblast cell types ( P <0.05), although fetal fibroblasts appeared least responsive and gingival fibroblasts most responsive to the inhibitory effects of this cytokine. Comparison of gel contraction by the different fibroblast strains indicated that fetal and gingival fibroblasts shared similar contraction kinetics. For the adult skin fibroblasts, three of five strains studied showed significantly diminished levels of gel contraction compared to fetal and gingival cells. This apparent difference in fibroblast phenotype may, at least in part, explain the fetal-like wound healing pattern seen in the oral mucosa.  相似文献   
140.
Membrane-bound CD14 acts as a receptor for lipopolysaccharide (LPS) on monocytes/macrophages and neutrophils. Studies have suggested that the activation of monocytes/macrophages by the binding of LPS to membrane-bound CD14 may require the association of a signal-transducing molecule with membrane-bound CD14. The observation that non-CD14 expressing cells, such as endothelial cells, can nevertheless be activated by a complex of LPS and a soluble form of CD14 (sCD14) suggests that the receptor for this complex may be identical to the signal transducing molecule associated with membrane-bound CD14. The studies described show that two CD14-specific MoAb are able to block the LPS-induced activation of endothelial cells but do not affect the response of monocytes to LPS. This suggests that the interaction of the sCD14:LPS complex with endothelial cells is distinct from the interaction of membrane-bound CD14 with its putative signal-transducing molecule.  相似文献   
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