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31.
A morphometrical analysis of the extent of hemosiderin deposits in 71 human skin wounds with post-infliction intervals between 2 days and 7 months was performed. Earliest positive findings were detectable in a lesion aged 3 days, and with increasing wound age an increase in the amount of hemosiderin occurred. A value of more than 20% of the microscopic field with hemosiderin deposits was found earliest 8 days after wounding and therefore the detection of considerable amounts of hemosiderin (arbitrarily defined as 20% or more of the evaluated area) indicates a minimum wound age of approximately 1 week. Since the extent of hemosiderin formation depends upon the extent of the initial hemorrhage and a physiological reduction in the amount of this pigment with advanced wound age, slight or absent hemosiderin deposits cannot provide information on the post-infliction interval. 相似文献
32.
Sally Betz Corradin Jacques Mauël Susanne Denis Donini Emilia Quattrocchi Paola Ricciardi-Castagnoli 《Glia》1993,7(3):255-262
Nitric oxide (NO) is a short-lived diffusable molecule now believed to participate in multiple physiologic functions in the CNS including neurotransmission and the maintenance of vascular tone. Previously, we reported that cell lines obtained by retroviral immortalization of tissue macrophages (M?;) could be induced to synthesize nitrite (NO), a stable end product of the NO synthetic pathway. We have further characterized the induction and activity of this pathway in a panel of seven microglial clones derived from primary embryonic mouse brain cultures. Like M?;, these clones were found to release high levels of NO-2 in response to recombinant interferon-γ (rIFN-γ) as a priming signal together with either bacterial lipopolysaccharide (LPS) or exogenous recombinant tumor necrosis factor-α (rTNF-α). As previously demonstrated for M?;, phagocytosis of zymosan particles during induction of enzyme activity enhanced subsequent NO production, which is of interest in light of the postulated phagocytic role of microglia within the CNS. Biochemical characterization of enzyme activity in intact microglial clones and in isolated cytosolic fractions indicates that the microglial NO synthase present in these murine cell clones represents the M?;-like isotype. These findings suggest that microglial cells could represent a major source of NO within the CNS. 相似文献
33.
Betz R 《Journal of healthcare materiel management》1992,10(2):67-68
Hospitals have entered into a new era of capital planning. A number of factors will influence hospital buying behavior now that the Medicare capital regulations are being implemented. As purchasing responsibility for additional departments is continually folded into hospitals' central purchasing function there will be increased opportunities for group contracts. As resources shrink and demand for services increases, GPOs will be relied upon for their expertise and financial finesse. The emphasis will be on boosting the use of group contracts among existing members, rather then seeking additional members in a shrinking hospital market. Through effective purchasing, it is generally recognized that a hospital can recover and keep, at best, 5-10 percent of the cost of all purchased goods and services. Group purchasing organizations need to develop better strategies of cooperation with vendors, distributors and hospitals to help providers control capital costs. In this challenging environment, GPOs will aggressively target markets other than acute care as the source of their future growth, just as healthcare facilities are branching out. To accommodate changing needs, the strongest GPOs will continue their evolution into structures more like alliances, offering an array of other cooperative and support programs beyond the purchase of goods and services. 相似文献
34.
Immunohistochemical localization of fibronectin as a tool for the age determination of human skin wounds 总被引:2,自引:0,他引:2
P. Betz A. Nerlich J. Wilskel J. Tübel I. Wiest R. Penning W. Eisenmenger 《International journal of legal medicine》1992,105(1):21-26
Summary We analyzed the distribution of fibronectin in routinely embedded tissue specimens from 53 skin wounds and 6 postmortem wounds. In postmortem wounds a faint but focal positive staining was exclusively found at the margin of the specimens which dit not extend into the adjacent stroma. Vital wounds were classified into 3 groups. The first comprising lesions with wound ages ranging from a few seconds to 30 min, the second comprising those with wound ages upt to 3 weeks, and the third group with lesions more than 3 weeks old. Ten out of 17 lesions with a wound age up to 30 min showed a clear positive reaction within the wound area. Three specimens in this group were completely negative, while in 4 additional cases the result was not significantly different from postmortem lesions. These 7 cases were characterized by acute death with extremely short survival times (only seconds). In wounds up to 3 weeks old fibronectin formed a distinct network containing an increasing number of inflammatory cells corresponding to the wound age. In 2 cases with a survival time of 17 days and in all wounds older than 3 weeks fibronectin was restricted to the surface of fibroblasts and to parallel arranged fibers in the granulation tissue without any network structures. We present evidence that fibronectin is a useful marker for vital wounds with a survival time of more than a few minutes. Fibronectin appears before neutrophilic granulocytes migrate into the wound area. Since a faint positive fibronectin staining is seen in postmortem lesions and bleedings, we propose that only those wounds which show strong positive fibronectin staining also extending into the adjacent stroma should be regarded as vital.This study was supported by a grant from the Deutsche Forschungsgemeinschaft (grant Ei 209/3-1) and by a grant from the Friedrich-Baur-Stiftung University of Munich 相似文献
35.
STUDY DESIGN: A multicenter cross-sectional study of parents' and patient's concerns and preferences regarding surgery for idiopathic scoliosis. OBJECTIVES: The purpose of this study was to analyze independently both the parents' and patients' assessments of upcoming surgery for idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: No group has recently reported querying patients and their parents regarding expectations, preferences, reasons, and concerns about and for surgical treatment of adolescent idiopathic scoliosis. METHODS: Ninety-one sets of parents and patients were separately asked to complete questionnaires regarding the patients' upcoming idiopathic scoliosis surgery. Patients' ages ranged from 9 to 18 years, and data were collected from four centers and seven surgeons (all active members of the Scoliosis Research Society) from April through December 1998. Thirty-nine questions covered concerns (n = 6), reasons for surgery (n = 14), expectations (n = 9), assessment of life as is (n = 5), and scar preference (n = 5). RESULTS: The greatest concern about the surgery expressed by both parents and patients was neurologic deficit. The least concern for both was location and appearance of the scar. The highest expectation and main reason for having the surgery was to reduce future pain and disability as an adult. Families would be either somewhat or very dissatisfied to spend the rest of life "as is." CONCLUSION: Although parents and patients had similar ratings and concerns, the parents' concerns were higher, and expectations were greater than the patients'. 相似文献
36.
Fluorescence diagnostic methods enable tumor visualization via specific excitation of endogenous or exogenous tumor-selective fluorescent markers and subsequent optical measurement of the induced fluorescence signals. In the following review, the reader will be given a clear and extensive understanding of all aspects of these methods relevant for ENT specialists. Apart from a demonstration of the clinical difficulties in the diagnosis of malignant tumors of the upper aerodigestive tract, a historical synopsis of fluorescence diagnosis and an explanation of the biophysical basics, this publication focuses mainly on a detailed discussion of the current status of research and a critical consideration of the commercially available systems for fluorescence diagnosis in ENT oncology. The topic is rounded off by a short account of possible future activities in this field. 相似文献
37.
Natalie A. Betz Heideh K Fattaey Brenda A. Westhoff Avelina Q. Paulsen Terry C. Johnson 《Breast cancer research and treatment》1997,42(2):137-148
Very few growth inhibitors have been identified whichcan inhibit the proliferation of a broad spectrumof human breast cancer cell lines. CeReS-18, anovel cell surface sialoglycopeptide growth inhibitor, can reversiblyinhibit the proliferation of both estrogen receptor positive(MCF-7) and negative (BT-20) human breast cancer celllines. In addition, at concentrations above those requiredfor the reversible inhibition of cell proliferation, CeReS-18can also induce cell death in MCF-7 cells.Changes in nuclear and cytoplasmic morphology, characteristic ofapoptosis, were detected in MCF-7 cells treated witha cytotoxic concentration of CeReS-18, and internucleosomal DNAcleavage was also observed. The sensitivity of MCF-7and BT-20 cells to the biological properties ofCeReS-18 could be influenced by altering the calciumconcentration in the extracellular growth medium, such thatwhen the calcium concentration in the environment wasdecreased, an increased sensitivity to CeReS-18-induced growth inhibitionand cytotoxicity were observed. The addition of thecalcium chelating agent EGTA to MCF-7 cells, culturedin a normal calcium environment, could mimic theincreased sensitivity to the biological effects of CeReS-18observed under reduced calcium conditions. 相似文献
38.
Interaction of the C-terminal tail region of the metabotropic glutamate receptor 7 with the protein kinase C substrate PICK1 总被引:5,自引:0,他引:5
El Far O Airas J Wischmeyer E Nehring RB Karschin A Betz H 《The European journal of neuroscience》2000,12(12):4215-4221
Group III metabotropic glutamate receptors (mGluRs) are highly enriched in the presynaptic terminals of glutamatergic synapses where they mediate feedback inhibition of neurotransmitter release. Here, we used the yeast two-hybrid system to identify a direct interaction of the C-terminal tail region of mGluR7 with the rat homologue of the protein kinase C substrate PICK1. This interaction is specifically mediated by the very C-terminal amino acids of the receptor and can be reconstituted in human embryonic kidney 293 cells by transfection of full-length mGluR7 and PICK1 cDNAs. Quantitative beta-galactosidase assays revealed that among the different group III mGluRs, mGluR7 is the major PICK1 binding partner although other subfamily members can also interact with PICK1. These data indicate that PDZ domain-containing proteins might contribute to the presynaptic localization of group III mGluRs. 相似文献
39.
C. Arens D. Reußner J. Woenkhaus A. Leunig C. S. Betz H. Glanz 《European archives of oto-rhino-laryngology》2007,264(6):621-626
Indirect fluorescence endoscopy of the larynx has proven to facilitate the detection and delineation of precancerous and cancerous
lesion. The different methods are easy to handle and can be performed on an outpatient basis. Early diagnosis of laryngeal
cancer and its precursor lesions is simplified. The aim of the present study is to compare indirect autofluorescence laryngoscopy
to 5-ALA-induced PPIX fluorescence laryngoscopy. In a prospective study, 56 patients with suspected precancerous or cancerous
lesions were primarily investigated by indirect autofluorescence laryngoscopy. In a second step 5-ALA-NaCl (0.6%) was topically
applied to the larynx by inhalation, and indirect fluorescence laryngoscopy repeated 2 h after application. Autofluorescence
as well as 5-ALA-induced fluorescence was induced by filtered light (375–440 nm) of a xenon short arc lamp and processed by
a CCD camera system (D-light-AF System, Storz, Tuttlingen, Germany). White-light and fluorescence images were digitally recorded,
immediately assessed for diagnosis and finally compared to pathohistological findings. Inconspicuous laryngeal mucosa presented
a typical green fluorescence signal in autofluorescence endoscopy, which turned blue during 5-ALA-laryngoscopy. Precancerous
and cancerous lesions displayed a loss of autofluorescence in autofluorescence endoscopy whereas increased protoporphyrin
IX fluorescence could be observed in 5-ALA laryngoscopy. Both imaging techniques were suitable to distinguish benign from
precancerous or cancerous lesions. In contrast PPIX fluorescence was easily recognized in scarred vocal folds. According to
our results, both non-invasive fluorescence imaging techniques are useful in the early diagnosis of laryngeal cancer. Moreover
autofluorescence can be used immediately without drug application and possible side effects. 5-ALA-induced fluorescence seems
to be more suited for diagnostic examination of mucosal lesions in recurrent precancerous and cancerous lesions after surgery. 相似文献