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51.
BACKGROUND: Osteopenia with decreased bone mineral density (BMD) is a frequent finding in renal allograft recipients. Data concerning the bone architecture in these patients do not exist, however. METHODS: We compared the bone architecture of 33 randomly assigned women (age 49 +/- 12 years), who had received renal allografts 5.6 +/- 5.3 years before the investigation, with 74 women (age 50 +/- 14 years) who were admitted for osteodensitometry. All patients underwent single-energy computed tomography (SEQCT) and a midvertebral high-resolution tomography with computer-assisted analysis of the trabecular vertebral body architecture. RESULTS: Progressive alteration of bone architecture was associated with increasing vertebral height loss of the vertebral body. Height reduction of a vertebral body of more than 15% was associated with a significantly lower BMD (-2.3 +/- 0.8 versus -1.1 +/- 1.1 standard deviations below normal BMD), a lower trabecular bone area (13 +/- 8% versus 42 +/- 22%) and a lower trabecular diameter (1.4 +/- 0.5 mm versus 2.2 +/- 0.8 mm) compared to recipients without height reduction. In comparison to a matched group of patients with similarly reduced BMD (1.1 +/- 1.2 versus 1.2 +/- 1.1 SD below normal BMD), renal allograft recipients showed a lower number of trabecular plates (5.6 +/- 3.1 versus 7.0 +/- 3.7) and a smaller intertrabecular surface (54 +/- 116 mm versus 75 +/- 138 mm). CONCLUSIONS: Alterations of bone architecture in renal allograft recipients were associated with progressive vertebral height loss. Despite similar bone mineral density, differences of bone architecture could be observed between renal allograft recipients and patients with osteoporosis.   相似文献   
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A 52 yr old Caucasian female (F. E.) had hemolytic anemia, a leukemoid reaction, and fatal sepsis due to Escherichia coli. Her leukocytes ingested bacteria normally but did not kill catalase positive Staphylococcus aureus, Escherichia coli, and Serratia marcescens. An H(2)O(2)-producing bacterium, Streptococcus faecalis, was killed normally. Granule myeloperoxidase, acid and alkaline phosphatase, and beta glucuronidase activities were normal, and these enzymes shifted normally to the phagocyte vacuole (light and electron microscopy). Intravacuolar reduction of nitroblue tetrazolium did not occur. Moreover, only minimal quantities of H(2)O(2) were generated, and the hexose monophosphate shunt (HMPS) was not stimulated during phagocytosis.These observations suggested the diagnosis of chronic granulomatous disease. However, in contrast to control and chronic granulomatous disease leukocytes, glucose-6-phosphate dehydrogenase activity was completely absent in F. E. leukocytes whereas NADH oxidase and NADPH oxidase activities were both normal. Unlike chronic granulomatous disease, methylene blue did not stimulate the hexose monophosphate shunt in F. E. cells. Thus, F. E. and chronic granulomatous disease leukocytes appear to share certain metabolic and bactericidal defects, but the metabolic basis of the abnormality differs. Chronic granulomatous disease cells lack oxidase activity which produces H(2)O(2); F. E. cells had normal levels of oxidase activity but failed to produce NADPH due to complete glucose-6-phosphate dehydrogenase deficiency. These data indicate that a complete absence of leukocyte glucose-6-phosphate dehydrogenase with defective hexose monophosphate shunt activity is associated with low H(2)O(2) production and inadequate bactericidal activity, and further suggest an important role for NADPH in the production of H(2)O(2) in human granulocytes.  相似文献   
54.

Anamnesis

A 53-year-old patient with known schizophrenia apparently suffered an acute aggravation of the underlying disease. The emergency physician found the patient in his apartment sitting naked on a chair and subsequently committed him to supervision psychiatry where he rapidly developed cardiopulmonary insufficiency. During the subsequent emergency transfer to the university clinic the patient started to show signs of an acute abdomen. On arrival at hospital the patient additionally developed anisocoria and troponin positive acute coronary syndrome (ACS).

Diagnosis and therapy

Emergency laparotomy revealed peritonitis due to gastric perforation making sepsis the probable main cause of the observed clinical symptoms. After abdominal surgery, cardiac catheterization and treatment of severe sepsis with multiorgan dysfunction syndrome, the man was discharged after 20 days in hospital.  相似文献   
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Platelet-derived growth factor promotes polymorphonuclear leukocyte activation   总被引:13,自引:0,他引:13  
Tzeng  DY; Deuel  TF; Huang  JS; Senior  RM; Boxer  LA; Baehner  RL 《Blood》1984,64(5):1123-1128
The platelet-derived growth factor (PDGF) has several well defined important biologic activities. Platelet-derived growth factor is the major mitogen in human serum for cells of mesenchymal origins; it is a potent chemoattractant protein for human monocytes, neutrophils, fibroblasts, and smooth muscle cells; and has been implicated in transformation by simian sarcoma virus and perhaps in transformation by other agents as well. In this article, PDGF has been shown to stimulate activation of human peripheral blood neutrophils defined by loss of membrane associated calcium as reflected by loss of chlortetracycline fluorescence, release of superoxide anion and specific granule enzymes, and enhanced neutrophil adherence and aggregation. These responses occurred in a dose-dependent fashion at concentrations of PDGF between 10 ng/mL (0.4 nmol/L) and 40 ng/mL (1.5 nmol/L) and were comparable to effects obtained with optimal concentrations of fMLP and C5a. Degranulation induced by PDGF was selective for secondary (specific) granules and not primary (azurophil) granules. Platelet-derived growth factor thus is ideally suited for a pivotal role in attracting inflammatory cells locally and initiating neutrophil activation at sites of blood vessel injury. Platelet-derived growth factor or a closely related protein also may play an important role in attracting and activating neutrophils in association with inflammatory tumors.  相似文献   
57.
本文对药物流产时在不同时间加用不同剂量的紫草对药物流产效果的影响进行探索。紫草的加用时间为米索前列醇 (简称米索 )应用前 3d、后 3d及前后共 6 d,剂量分别为 5 0 g、75 g和 1 0 0 g。 1 35 0例早孕妇女分成 9个研究组进行观察。结果表明 :在米索应用前 3d和前后 6 d加用紫草效果较米索应用后 3d加用紫草在完全流产率和出血时间两方面效果明显改善 (P均 <0 .0 5 )。紫草用量 5 0~ 1 0 0 g时流产效果与紫草剂量无明显相关。因此我们认为药物流产时在应用米索前紫草与米非司酮同时应用效果较好 ,剂量以5 0 g较为合理  相似文献   
58.
Standard isolation techniques for the human polymorphonuclear leukocyte (PMN) involve sequential exposure of cells to the nonphysiologic environments of dextran, Ficoll-Hypaque (FH) gradient centrifugation, and hypotonic conditions. It has been suggested that these may be harmful to the recovered PMN. Counterflow centrifugal elutriation (CCE) allows separation of human PMNs while the cells are continuously bathed in a physiologic and isotonic buffer. To investigate whether preparative technique may alter PMN activation, we compared PMNs obtained by these two methods for stimulus-induced superoxide production and release of primary and specific granule contents. Resting PMN volume was also evaluated. We observed that PMNs obtained using the CCE method were larger and released significantly more superoxide and specific granule contents than PMNs obtained by the standard FH technique. The possible origins for these differences are discussed.  相似文献   
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Recent progress in oculomotor research has enabled new insights into the functional neuroanatomy of the human premotor oculomotor brainstem network. In the present review, we provide an overview of its functional neuroanatomy and summarize the broad range of oculomotor dysfunctions that may occur in Huntington's disease (HD) patients. Although some of these oculomotor symptoms point to an involvement of the premotor oculomotor brainstem network in HD, no systematic analysis of this functional system has yet been performed in brains of HD patients. Therefore, its exact contribution to oculomotor symptoms in HD remains unclear. A possible strategy to clarify this issue is the use of unconventional 100-µm-thick serial tissue sections stained for Nissl substance and lipofuscin pigment (Nissl-pigment stain according to Braak). This technique makes it possible to identify the known nuclei of the premotor oculomotor brainstem network and to study their possible involvement in the neurodegenerative process. Studies applying this morphological approach and using the current knowledge regarding the functional neuroanatomy of this human premotor oculomotor brainstem network will help to elucidate the anatomical basis of the large spectrum of oculomotor dysfunctions that are observed in HD patients. This knowledge may aid clinicians in the diagnosis and monitoring of the disease.  相似文献   
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