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191.

Background  

A standardised suction technique has been used to sample plasma proteins in dermal interstitial fluid (IF) serially for 5 to 6 days from a suction-induced skin mini-erosion. Increased protein concentrations ascribed to inflammation have been shown from day 1 onward. In this study, we assessed the effect of two different extraction pressures on IF sample composition.  相似文献   
192.
193.
颈动脉内膜切除术的恰当应用   总被引:2,自引:0,他引:2  
在颈动脉内膜切除术(CEA)首创的头30年里,一直没有明确的标准来确定哪些颈内动脉疾病患者适合这一手术.最近,从7项临床随机试验中得出了哪些有症状与无症状患者适合行CEA的结论.对于颈内动脉狭窄70%以上的患者,卒中的危险性最大,手术的益处也最大.在这些研究中,CEA对以下患者最有益半球短暂性脑缺血发作、颅内外联合病灶和无侧支循环且除此之外身体状况良好的老年患者.下列患者虽然能从手术中获益,但围手术期卒中和死亡的危险性较高广泛白质疏松、对侧颈内动脉闭塞和腔内有血栓者.狭窄50%~69%的患者较少获益,包括女性和仅有一过性单眼盲在内的一些患者行CEA甚至可能有害.腔隙性卒中和一侧颈内动脉接近闭塞的患者有手术指征,但益处不大;狭窄<50%的患者不能从手术中获益.在最大的一项无症状患者随机试验中,围手术期卒中和死亡的危险性非常小(1.5%),但要在2年内防止1例卒中发生需要相当多的病例(83例)接受CEA治疗.以后的文献报道围手术期危险性较高(2.8%~5.6%).近一半无症状患者的卒中是心源性栓塞和小血管疾病所致.这些局限性抵消了任何潜在的益处.其他试验正在进行,并可能确认哪些无症状患者亚组可从手术中获益.同时,大多数无症状患者内科治疗效果也较好.  相似文献   
194.
It has been previously demonstrated that the generation of measles virus (MV)-specific cytotoxicity (CTL) is reduced in patients with multiple sclerosis (MS). By contrast, CTL specific for influenza virus (FLU) and mumps virus is normal. It is uncertain if reduced CTL is limited to MV in MS patients, or if reduced CTL may be found to other viruses as well. Since MV-specific CTL is predominantly restricted by HLA class II molecules, while FLU-specific and mumps-specific CTL have large HLA class I-restricted components, reduced MV-specific CTL may reflect a broader reduction in HLA class II-restricted CTL in patients with MS. To examine this question we studied the generation of CTL specific for herpes simplex virus type I (HSV). HSV-specific CTL, like MV-specific CTL is predominantly restricted by HLA class II molecules. We found that patients with MS had reduced generation of CTL to both MV and HSV. Most, but not all patients who had reduced generation of CTL to one virus also had a similar impairment with respect to the second virus. Some patients, however, had a reduction in the generation of CTL only to MV or to HSV. These findings extend our earlier observations regarding reduced MV-specific CTL in patients with MS to a second HLA class II-restricted virus, HSV. Such a reduction may reflect discrete impairments in immune function to separate viruses, possibly those that are associated with viral persistence, or may reflect a more generalized defect in HLA class II-restricted CTL.  相似文献   
195.
196.
OBJECTIVE: To obtain consensus among a panel of experts on performance measures useful for evaluating the quality of hospital-based domestic violence (DV) programs. METHODS: The Delphi process of consensus development was used with a panel of 18 experts including DV researchers, program planners, and advocates. Three rounds were conducted over a period of six months, with each round involving the completion of a written questionnaire. Panelists were instructed to concentrate on structure and process measures of DV program performance. Health outcome measures were not considered. During each round, panelists rated (scale of 1-5) their level of agreement with each measure, in terms of the measure's usefulness for evaluating hospital-based DV programs. Data were entered into SPSS on a personal computer and frequency distributions, measures of central tendency, and variance were computed for each measure. Consensus development was defined as a reduction in the item-specific variance from one round to the next. RESULTS: A total of 37 performance measures were agreed upon. These measures fell within nine different domains of DV program activities, including: Policies and Procedures, Hospital Physical Environment, Hospital Cultural Environment, Training of Providers, Screening and Safety Assessment, Documentation, Intervention Services, Evaluation Activities, and Collaboration. CONCLUSIONS: A number of measures have been identified as useful for evaluating hospital-based DV programs. Use of these measures should assist researchers, program planners, and administrators in assessing the quality of hospital-based DV programs.  相似文献   
197.
This paper reports the proceedings of the discussion panel assigned to look at clinical aspects of quality in emergency medicine. One of the seven stated objectives of the Academic Emergency Medicine consensus conference on quality in emergency medicine was to educate emergency physicians regarding quality measures and quality improvement as essential aspects of the practice of emergency medicine. Another topic of interest was a discussion of the value of information technology in facilitating quality care in the clinical practice of emergency medicine. It is important to note that this is not intended to be a comprehensive review of this extensive topic, but instead is designed to report the discussion that occurred at this session of the consensus conference.  相似文献   
198.
Cough and paradoxical vocal fold motion   总被引:8,自引:0,他引:8  
OBJECTIVES: The differential diagnosis and treatment of patients with chronic cough, paradoxical vocal fold motion, and disordered breathing can be a challenge to most practicing otolaryngologists. Tracheobronchial (ie, asthma, bronchitis, and tracheal stenosis), laryngeal (ie, vocal fold paralysis and neoplasms), and rhinologic (ie, allergies and rhinosinusitis) etiologies are commonly diagnosed and treated effectively. However, occasionally one is faced with patients who are refractory to medical treatment and have no obvious rhinologic, laryngeal or pulmonary cause. STUDY DESIGN AND SETTING: We conducted a review of the literature. METHODS: We present a thorough review of the current medical literature exploring the complex neurologic mechanisms involved in the production of cough and the relationship between gastroesophageal reflux disease, vagal neurapathy, and paradoxical vocal fold motion. RESULTS: The diagnosis and successful treatment of chronic cough can be complex. It requires a thorough understanding of the neurologic mechanisms behind cough excitation and suppression. Successful treatment strategies include aggressive management of the patient's reactive airway disease, gastroesophageal reflux disease, and, in select cases, paradoxical vocal fold motion. This may involve a well-coordinated effort among pulmonologists, otolaryngologists, gastroenterologists, and speech pathologists. CONCLUSION: Gastroesophageal reflux disease, vagal neuropathy, and paradoxical vocal fold motion are additional causes of chronic cough and disordered breathing that need to be considered, in the absence of obvious laryngotracheal and/or rhinologic pathology. A high index of suspicion is essential in making the diagnosis and formulating an effective multidisciplinary treatment plan for these patients.  相似文献   
199.
Angiogenesis induction and regression in human surgical wounds   总被引:2,自引:0,他引:2  
Angiogenesis in human wound healing is not well characterized, with only sparse information available regarding the maturation and fate of vessels formed as a consequence of human tissue repair. Therefore, this study aimed to establish the temporal profile of angiogenesis in human dermal wounds. Punch biopsies were obtained under local anesthesia from 45 patients following breast surgery. Scars were predominantly between 2 and 52 weeks after surgery but in five patients were > 52 weeks. Control samples were taken from breast skin peroperatively (n = 24). Quantification of vascular density was performed using the Chalkley grid, following antibody staining for platelet endothelial cell adhesion molecule. Vascular patterns, wound cellularity and morphology were also determined. Cumulative microvessel density was increased in all samples when compared to controls (p < 0.05). This was greatest 2 to 24 weeks following surgery 17 (15-21) median (range), decreased thereafter, but remained elevated compared to controls even in the mature scars > 52 weeks. Control tissue showed an ordered morphological arrangement of dermal structures, collagen, and elastic fibers. However, wounding resulted in marked structural distortion for up to 15 weeks. In conclusion, this study shows for the first time the prolonged persistence of both microvessels and cellularity (fibroblastic cells), in addition to structural distortion in human dermal wounds, which is in contrast to previous in vitro and in vivo studies.  相似文献   
200.
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