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排序方式: 共有1378条查询结果,搜索用时 31 毫秒
1.
Topical Metronidazole Gel 总被引:1,自引:0,他引:1
Joseph A. Witkowski M.D. Lawrence Charles Parish M.D. 《International journal of dermatology》1991,30(9):660-661
Ten putrid-smelling decubitus ulcers were successfully treated with metronidazole gel. Anaerobes were cultured from five ulcers and Wood's light examination was positive in four ulcers before treatment. The odor was eliminated after 36 hours of therapy. All results of post-treatment cultures of anaerobes and Wood's light examinations were negative. 相似文献
2.
Motility disorders of the gastrointestinal (GI) tract have traditionally been diagnosed by excluding mechanical small-bowel obstruction. In order to diagnose GI motility disorders in a positive fashion, small-bowel manometry was performed on 15 patients who were referred to the authors with intestinal motility disorders. Intestinal manometry was performed after first positioning a 200-cm multilumen tube into the small intestine. Ports located at 10-cm intervals were perfused with sterile water and connected to pressure transducers to record intraluminal pressures with a multichannel chart recorder. This low compliance water perfusion manometry system allowed examination of both fasting and postprandial motility. Intestinal manometry was able to assist in the diagnosis of two patients that had true mechanical small-bowel obstruction. One patient had a stenosis of the gastrojejunostomy and three patients had a functional gastric outlet obstruction secondary to a motility disorder in the Roux limb. One patient had a functional obstruction from a reversed jejunal loop and eight patients were identified as having intestinal pseudo-obstruction. We found intestinal manometry was a helpful adjunct in the diagnosis of GI motility disorders. 相似文献
3.
The stability of phenytoin in blood collected in plain and serum separator tubes (SSTs) was investigated under simulated storage and transport conditions. The drug was generally more stable in plain collection tubes than in SSTs. No degradation occurred in plain red-top tubes or in refrigerated SSTs, but clinically significant degradation was present in SSTs stored at room temperature (25 degrees C) and at elevated temperature (32 degrees C) 24 h after collection. The mean loss was 17.9% at 25 degrees C and 25.9% at 32 degrees C. It is recommended that if blood is to be transported or stored in SSTs, the samples be refrigerated unless assay can be performed within 8 h. 相似文献
4.
Cardiac magnetic resonance (MR) imaging has developed rapidly to rival echocardiography as a noninvasive imaging modality. Anatomic detail may exceed that currently available using echocardiography techniques, and the ability to image moving protons may compete with Doppler color flow mapping in detecting valvular diseases and shunts. Because of the considerable clinical experience with echocardiography, as angled MR imaging planes become available as standard software packages, it may be useful for MR cardiac imaging to use standard, accepted echocardiographic nomenclature and imaging planes. This article describes the principles used to obtain long and short axis MR images that are comparable with echocardiographic imaging planes. Diagrams and illustrations are provided to orient the viewer using nomenclature common to echocardiography. These views may eventually be useful for functional analysis of the left ventricle and for detection and evaluation of valvular heart disease and intracardiac shunts. 相似文献
5.
The activities of several flavonoids and the related nonflavonoid compound epicatechin were compared with respect to Cu(II)-induced strand scission of DNA by using two different assays. The same series of compounds was used to study the stoichiometry of Cu(II) reduction in the absence of DNA. The compounds were compared for their ability to generate superoxide, hydrogen peroxide and the Cu(II)-dependent production of hydroxyl radicals. Flavonoids were examined to assess the production of a charge-transfer complex with Cu and the rate of decay of the complexes were compared. All the compounds tested had some ability to cause DNA strand scission in the presence of Cu(II), with myricetin being the most active and galangin the least active. The ability to cause such scission correlated with the rate of decay of the charge-transfer complex, the ability to generate active oxygen species and with the stoichiometry of Cu(II) binding. Analysis of the data in the light of the structural differences between the flavonoids led to a discussion of alternative Cu(II)-sequestering mechanisms. 相似文献
6.
Patricia A. Ludowyk David O. Willenborg Christopher R. Parish 《Journal of neuroimmunology》1992,37(3):237-250
Using experimental autoimmune encephalomyelitis (EAE) in the rat as a model of central nervous system (CNS) inflammation, activated and quiescent T lymphocytes with different antigen specificities were labelled with the fluorescent dye Hoechst 33342 and tested by fluorescence microscopy for their ability to accumulate in different regions of the spinal cord and in other organs at varying times post inoculation. With this highly sensitive assay it was found that activated myelin basic protein (MBP)-specific T cell lines accumulated in the spinal cord (a 1000-fold increase in the lumbar/sacral region by day 4) and caused clinical signs of EAE. In contrast, interleukin-2 (IL-2)-maintained (quiescent) MBP-specific T cell lines failed to accumulate in the CNS and cause disease. Activated ovalbumin (OA)-specific and purified protein derivative of tuberculin (PPD)-specific T cell lines were also found at significantly higher levels in the spinal cord than non-activated cells although they failed to accumulate to a substantial degree when injected alone. When injected with activated MBP-specific T cells the activated OA- and PPD-specific cell lines accumulated in the spinal cord following initial accumulation of the MBP-specific cells, demonstrating that during the inflammatory process there is considerable non-specific recruitment of cells into the inflammatory site. CNS accumulation of activated MBP-specific T cell lines occurred 1-2 days later in irradiated animals than in non-irradiated recipients. This was consistent with irradiated animals also exhibiting a later onset of disease and suggests that irradiation may directly affect the endothelium in a way that makes it less adhesive. In conclusion, this study demonstrates that activated lymphocytes of any specificity enter the spinal cord, and that the neuro-antigen specific cells accumulate there and lead to the recruitment of other cells. Non-activated cells, even those with neural antigen specificity fail to enter the cord. Understanding the nature of what an 'activated' lymphocyte is may allow us to design strategies to inhibit such immune-mediated inflammation. 相似文献
7.
Parish P Sedghizadeh Derek Wong Charles F Shuler Vincent Linz John R Kalmar Carl M Allen 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(2):e30-e34
The calcifying epithelial odontogenic tumor (CEOT), or Pindborg tumor, is a rare and benign odontogenic neoplasm that affects the jaw. The most common manifestation of CEOT is a unifocal or localized lesion of the involved jaw, which may appear clinically as a hard tissue swelling and radiographically as a mixed radiolucent-radiopaque mass. In this article, we present a unique case of CEOT affecting multiple sites in the maxilla and mandible of a 51-year-old white man. Though biopsy samples from all involved sites revealed similar histopathologic features consistent with CEOT, the fact that there was a multifocal presentation is an unusual phenomenon for CEOT and has never been reported. Multifocal odontogenic lesions are not typical but have been observed in conditions associated with known genetic mutations. For example, multiple odontogenic keratocysts are the most common feature of the inherited condition known as nevoid basal cell carcinoma syndrome. This case, however, is the first one to demonstrate that there may be a multifocal variant of CEOT that has not been previously recognized. 相似文献
8.
This paper describes attempts to isolate and characterize glycosaminoglycan (GAG)-binding molecules on the surface of lymphocytes and lymphoma cell lines and relate their expression to splenic and lymph node homing capacity. Initial binding studies with radiolabelled GAG and rosetting studies with GAG-coupled erythrocytes revealed that there are receptors on lymphocytes for the major classes of GAG (i.e. hyaluronic acid, chrondroitin sulfates, heparin), but lymphocytes bind heparin much more avidly than other GAG species. Analysis of the binding of solubilized radiolabelled cell-surface molecules to immobilized GAG revealed cell-type specific expression of GAG-binding molecules. Thus, each of four lymphoma cell lines tested gave a characteristic pattern of GAG-binding molecules, some molecules being unique to a particular cell line and others being shared by some of the lines. Similarly, splenocytes expressed at least 10 distinct GAG-binding molecules with molecular weights (MW) ranging from 10,000 to 100,000, whereas thymocytes expressed additional GAG-binding proteins of 190,000 and 250,000 MW. Furthermore, splenocytes differed from thymocytes by possessing a unique family of cell-surface molecules which reacted with each GAG. Immunoprecipitation studies demonstrated that the GAG-binding molecules on splenocytes did not correspond to any of the cell-surface antigens tested, notably the cell adhesion molecules MEL-14, CD11/CD18 and CD44, although CD8 bound weakly to heparin. Four lymphoma cell lines with well-characterized migration properties were examined for GAG-binding molecules which may control lymphocyte migration. It was found that no one GAG-binding protein could be correlated with the entry of cells into a particular lymphoid organ. Nevertheless, the role of GAG-binding molecules in the subsequent positioning of lymphocytes within lymphoid organs requires further investigation. 相似文献
9.
Morphine-6beta-glucuronide modulates the expression of inducible nitric oxide synthase 总被引:1,自引:0,他引:1
The immunomodulatory effects of morphine are well established; however, suprisingly little is known about the immunomodulatory properties of the major metabolites of morphine. The present study tests the hypothesis that expression of inducible nitric oxide synthase (iNOS) is modulated by the administration of the morphine metabolite, morphine-6-glucuronide. The initial study using rats shows that morphine-6-glucuronide administration (0, 1.0, 3.163, 10 mg/kg s.c.) results in a pronounced reduction in lipopolysaccharide (LPS)-induced expression of iNOS (inducible nitricoxide synthease) in spleen, lung, and liver tissue as measured by western blotting. Morphine-6-glucuronide also produces a reduction in the level of plasma nitrite/nitrate, the more stable end-product of nitric oxide degradation. In a subsequent study, administration of the opioid receptor antagonist, naltrexone (0.1 mg/kg) prior to the injection of morphine-6-glucuronide (10 mg/kg) blocks the morphine-6-glucuronide induced reduction of iNOS expression and plasma nitrite/nitrite levels indicating that the effect is mediated via the opioid-receptor. This study provides the first evidence that morphine-6-glucuronide alters the expression of iNOS. 相似文献
10.
A 1.0-kb DNA fragment, corresponding to an internal region of the Neurospora crassa glucoamylase gene, gla-1, was generated from genomic DNA by the polymerase chain reaction, using oligonucleotide primers which had been deduced from the known N-terminal amino-acid sequence or from consensus regions within the aligned amino-acid sequences of other fungal glucoamylases. The fragment was used to screen an N. crassa genomic DNA library. One clone contained the gene together with flanking regions and its sequence was determined. The gene was found to code for a preproprotein of 626 amino acids, 35 of which constitute a signal and propeptide region. The protein and the gene are compared with corresponding sequences in other fungi. 相似文献