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51.
52.
OBJECTIVES: We undertook to evaluate the microbiology of acute exacerbation of chronic sinusitis (AECS). METHODS: Repeated aspirations of maxillary sinus secretions by endoscopy were performed in 7 patients over a period of 125 to 242 days. RESULTS: Bacteria were recovered for all 22 aspirates, and the number of isolates was between 2 and 4. A total of 54 isolates were isolated: 16 aerobic and facultative bacteria and 38 anaerobic bacteria. The aerobic bacteria were Haemophilus influenzae (7 isolates), Streptococcus pneumoniae (3), Moraxella catarrhalis (3), Staphylococcus aureus (2), and Klebsiella pneumoniae (1). The anaerobic bacteria included pigmented Prevotella and Porphyromonas spp (19), Peptostreptococcus spp (9), Fusobacterium spp (8), and Propionibacterium acnes (2). A change in the types of isolates was noted in all consecutive cultures obtained from the same patients as different organisms emerged and previously isolated bacteria were no longer recovered. An increase in antimicrobial resistance was noted in 6 instances. CONCLUSIONS: This study illustrates the microbial dynamics of AECS in which anaerobic and aerobic bacteria prevail, and highlights the importance of obtaining cultures from patients with AECS for guidance in selection of proper antimicrobial therapy. 相似文献
53.
Some, but not all chronically demyelinated MS lesions are depleted of oligodendrocyte progenitor cells (OPCs) suggesting that OPCs are destroyed during the process of demyelination and some factor impedes OPC repopulation of the depleted tissue. The chronically demyelinated axons in MS lie in an astrocytic environment and it has been proposed that this might impede entry of OPCs into such regions. By depleting a short length of spinal cord of its OPCs using 40 Gy of X-irradiation in both normal rats and rats with progressive myelin loss accompanied by an astrocytosis (taiep rats), we investigated whether such changes affect the ability of OPCs to repopulate OPC-depleted tissue. In both taiep and normal rats, the rate of repopulation decreases with age, but no difference was detected in the rate at which OPCs repopulated normally myelinated and chronically demyelinated and astrocytosed tissue. This indicates that, if the astrocytic environment of the taiep CNS is comparable to that found in MS lesions, then the presence of chronically demyelinated axons and astrocytosis in chronic MS lesions does not represent a barrier to repopulation of the tissue by OPCs. However, similar to the situation in the normal adult rodent CNS, the rate of repopulation by endogenous OPCs in aged taiep rats is very slow, approximately 0.2 mm per week. 相似文献
54.
Rosenblum A Foote J Cleland C Magura S Mahmood D Kosanke N 《The American journal of drug and alcohol abuse》2005,31(1):35-58
Patient treatment matching hypotheses were tested for substance users randomly assigned to a group cognitive behavioral therapy (CBT; n= 114) or a group motivational intervention (GMI; n= 116). Treatment was scheduled twice weekly for 10 weeks. Using a patient attribute by treatment interaction design with a 15-week follow-up, the study predicted that alexithymia, antisocial personality disorder (ASPD), and network support for alcohol and drug use would be associated with less substance use for CBT subjects and that hostility and lower treatment motivation would be associated with less substance use for GMI subjects. Three of the hypothesized moderators were empirically supported: alexithymia, network support for alcohol, and ASPD. Results indicate the use of assessing specific patient attributes to better inform treatment recommendations. 相似文献
55.
OBJECT: The aim of this study was to determine the incidence and magnitude of coordinate setting slippage during gamma knife surgery (GKS). METHODS: Thirty-six consecutive patients undergoing GKS with a Leksell unit between June and December 2000 had their coordinates (right and left x-, y-, and z-coordinates; 1548 coordinates; 258 isocenters) and gamma angles checked after the delivery of treatment to each isocenter to determine whether the coordinate settings had slipped and, if so, which settings and the magnitude of the slippage. CONCLUSIONS: Coordinate setting slippage during GKS with a Leksell unit does occur but is rare. The magnitude of such slippage is typically within the error of the stereotactic system and coordinate reading. The authors noted that coordinate setting slippage is significantly correlated with patient weight. 相似文献
56.
57.
Foote JA Kemmeter PR Prichard PA Baker RS Paauw JD Gawel JC Davis AT 《JPEN. Journal of parenteral and enteral nutrition》2004,28(3):154-157
BACKGROUND: Early postpyloric feeding is considered the accepted method of nutrition support in critically ill patients. Endoscopic and fluoroscopic techniques are associated with the highest percentage of successful placement. The purpose of this study was to compare endoscopic vs fluoroscopic placement of postpyloric feeding tubes in critically ill patients. METHODS: This is a randomized prospective clinical trial. Forty-three patients were randomized to receive feeding tubes by endoscopic or fluoroscopic technique. All procedures were performed at the bedside in the critical care unit. A soft small-bore nonweighted feeding tube was used in all cases. Successful placement was confirmed by either an abdominal x-ray for endoscopic technique or a fluoroscopic radiograph for fluoroscopic technique. RESULTS: Postpyloric feeding tubes were successfully placed in 41 of 43 patients (95%). The success rate using endoscopic technique was 96% (25 of 26), whereas the rate using fluoroscopy was 94% (16 of 17). The average time of successful placement was 15.2 +/- 2.9 (mean +/- SEM) minutes for endoscopic placement and 16.2 +/- 3.2 minutes for fluoroscopic placement, which was not statistically significant (p > .05). CONCLUSIONS: Endoscopic and fluoroscopic placement of postpyloric feeding tubes can safely and accurately be performed at the bedside in critically ill patients. Our results showed no significant difference in the success rate or time of placement between endoscopic vs fluoroscopic placement of postpyloric feeding tubes. 相似文献
58.
A DNA mutation detection protocol able to identify and characterize a previously unknown change in a given sequence in a rapid, efficient, sensitive, and inexpensive manner is required to take advantage of the resources now available to researchers through the genome sequencing projects. We have developed a method based on base-specific cleavage of polymerase chain reaction (PCR) products and then separation of the fragments by matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS), which can meet these criteria. Differences are seen as the presence, absence, or mass change of peaks corresponding to fragments affected by the base difference. This technique is shown through the detection of a polymorphism in the 3' untranslated region of IL12p40 from a double-stranded PCR product, and the detection of a single nucleotide polymorphism between two mouse strains. The sensitivity of the technique can be increased with the use of postsource decay, which enables differentiation of two fragments of identical mass but different sequence. The level of specificity and the rapid sample analysis time lend this technique to the mass screening of individuals for sequence changes and, in combination with MS sequencing methods, could be used to facilitate rapid resequencing of DNA. 相似文献
59.
Staines G Kosanke N Magura S Bali P Foote J Deluca A 《Journal of addictive diseases》2003,22(Z1):61-77
The study examined the convergent validity of the ASAM Patient Placement Criteria (PPC) by comparing Level of Care (LOC) recommendations produced by two alternative methods: a computerdriven algorithm and a "standard" clinical assessment. A cohort of 248 applicants for alcoholism treatment were evaluated at a multi-modality treatment center. The two methods disagreed (58% of cases) more often than they agreed (42%). The algorithm recommended a more intense LOC than the clinician protocol in 81% of the discrepant cases. Four categories of disagreement accounted for 97% of the discrepant cases. Several major sources of disagreement were identified and examined in detail: clinicians' reasoned departures from the PPC rules, conservatism in algorithm LOC recommendations, and measurement overlap between two specific dimensions. In order for the ASAM PPC and its associated algorithm to be embraced by treatment programs, the observed differences in LOC recommendations between the algorithm and "standard" clinical assessment should be resolved. 相似文献
60.
Fisher J Scott C Scarantino CW Leveque FG White RL Rotman M Hodson DI Meredith RF Foote R Bachman DG Lee N 《International journal of radiation oncology, biology, physics》2003,56(3):832-836
PURPOSE: To determine whether prevention of hyposalivation after curative radiotherapy (RT) to the head and neck improves patients' quality of life (QOL). METHODS AND MATERIALS: Patients were to receive at least 50 Gy to 50% of the volume of the major salivary glands, provide unstimulated and stimulated saliva samples, and complete the University of Washington head-and-neck QOL tool before RT and 3 and 6 months after RT. Patients were randomized to receive pilocarpine 5 mg or placebo q.i.d. RESULTS: A total of 249 patients was randomized between March 1998 and January 2000. Of these, 214 were eligible for QOL analysis. Patients were evenly distributed between arms by race, gender, tobacco use, tumor site, T stage (50% T2-T3), and salivary function. A Karnofsky performance status of 90% was more common in the pilocarpine arm. Twenty percent of the patients on the pilocarpine arm and 29% of the patients on the placebo arm were taking nutritional supplements. The placebo arm patients had greater mouth pain and chewing difficulties. Compliance for the QOL tool at 3 and 6 months was 65% and 50%, respectively. Despite statistically significant (p = 0.047 and p = 0.049, respectively) preservation of salivary function in the pilocarpine arm, patients on the pilocarpine arm reported difficulties with swallowing (75%), activity (80%), hyposalivation (64%), and taste (81%). No difference was noted between arms at 3 months in mucositis scores, with both arms demonstrating increased requirement for oral nutrients. CONCLUSION: Objective prevention of hyposalivation did not affect patients' assessment of salivary function or QOL because of the greater impact mucositis plays in QOL after RT. 相似文献