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141.
Blepharitis patients have a number of disturbances in their tear film associated with meibomian gland dysfunction that affect evaporation and tear osmolarity. We tested a series of 156 consecutive patients, with a presumed diagnosis of blepharitis, dry eye, or allergic disease, and a series of 72 normals. We compared their tear film characteristics using tear osmolarity, tear volume, tear production (fluorophotometric and Schirmer test), tear turnover (decay constant), tear evaporation, and meibomian gland function evaluated by gland drop-out, expressed lipid viscosity, and volume. Of the 156 patients tested, we found 37 had dry eye, 10 had only allergic disease, 73 had meibomian gland dysfunction and dry eye, and 36 had only meibomian gland dysfunction. We created a model of the relative influence some of these factors had on each other using their correlation coefficients. The highest correlations for osmolarity were Schirmer test (-0.44), lipid volume low (-0.44), lipid viscosity high (0.39), gland drop-out (0.39), and tear evaporation (0.36). With regression analysis we accounted for 47% of the total variation in osmolarity, but only 17% of the variation in tear evaporation. We also present our classification system for blepharitis and dry eye patients based on our measurable physiologic parameters.  相似文献   
142.
Aspiration pneumonia following surgically placed feeding tubes   总被引:1,自引:0,他引:1  
BACKGROUND: The enteral route is preferred in surgical patients requiring nutritional support; however, controversy surrounds the choice of location of feeding tube placement. Although jejunostomy has been commonly accepted as superior to gastrostomy for long-term nutritional support because of an assumed lower risk of aspiration pneumonia, recent studies suggest that reevaluation of common practices of surgical tube placement is warranted. PATIENTS AND METHODS: We conducted a retrospective chart review of gastrostomy and jejunostomy procedures from 1986 to 1993. Demographic information and complications related to the procedure were reviewed. Aspiration pneumonia was defined as respiratory symptoms, leukocytosis, and infiltrate on chest radiograph. RESULTS: Sixty-nine gastrostomies and 86 jejunostomies were performed during the study period. Six patients were diagnosed with aspiration pneumonia; 2 cases of which occurred with jejunostomy and 4 cases occurred with gastrostomy (P = not significant). CONCLUSIONS: There was no difference in rates of pulmonary aspiration or other complications between gastrostomy and jejunostomy. We suggest that when a surgically placed feeding tube is required, the determination of appropriate procedure be based on clinical factors such as the technical difficulty of the operation or long-term feeding goals.  相似文献   
143.
144.
Increased concentrations of exhaled nitric oxide (NO) occur in patients with asthma, and exhaled NO may be useful for assessing the effect of drug therapy on airway inflammation. Beta2-agonists have been proposed to have both proinflammatory and anti-inflammatory effects. We therefore assessed exhaled NO after beta2-agonists in asthmatic patients. Two randomized, double-blind, placebo-controlled studies were conducted. Firstly, exhaled NO was measured in 18 asthmatics (9 taking inhaled glucocorticosteroids (GCS)) before and after nebulized salbutamol (5 mg), or identical placebo (0.9% saline). Exhaled NO and forced expiratory volume in one second (FEV1) were measured at 15 min intervals for 1 h (Study 1). Secondly, the effect of 1 week of treatment with the long-acting beta2-agonist, salmeterol (50 microg b.i.d.), added to either budesonide (800 microg b.i.d.) or placebo, was studied in eight mild asthmatic subjects (Study 2). Exhaled NO was measured by a chemiluminescence analyser, adapted for on-line recording. In Study 1, exhaled NO showed no significant change at any time-point in patients not taking inhaled GCS. In asthmatics on inhaled GCS, exhaled NO increased compared to placebo at 15 and 30 min, but this did not reach statistical significance. In Study 2, treatment with salmeterol increased FEV1, but exhaled NO levels were not significantly changed, either after budesonide treatment (143+/-35 to 179+/-67 ppb), or after placebo (201+/-68 to 211+/-65 ppb). Our results confirm that single high dose salbutamol does not increase exhaled nitric oxide in asthmatics not taking inhaled glucocorticosteroids. Salbutamol may increase exhaled nitric oxide in asthmatics taking inhaled glucocorticosteroids. However, regular use of salmeterol resulted in no change in exhaled nitric oxide, either used alone or in combination with inhaled glucocorticosteroids.  相似文献   
145.
146.
ALX40-4C is an antiretrovirus agent that has been found to have some inhibitory properties against human immunodeficiency virus (HIV) replication in vitro. The compound was designed as a competitor of the HIV Tat protein for TAR binding. In addition to its anti-HIV properties, it has demonstrated the ability to inhibit in vitro replication of herpes simplex virus types 1 and 2 as well as human cytomegalovirus. Subsequently, in vivo pharmacokinetic evaluation of ALX40-4C necessitated the establishment of a detection system for the measurement of ALX40-4C in subject serum. For this purpose, an indirect-competition enzyme-linked immunosorbent assay with generated rabbit anti-ALX40-4C antiserum was developed. The original assay took 12 h to complete and required many manipulations. Herein, we describe alterations to the system that resulted in the overall reduction in assay time and manipulation. We demonstrate that our alterations do not affect the specificity or sensitivity of the assay compared to that of the original system. ALX40-4C levels in spiked serum samples as well as drug levels from patient samples were used to validate the assay.  相似文献   
147.
Risk of colorectal cancer recurrence has traditionally been determined by use of pathologic staging. However, it is apparent that subgroups of patients exist within tumor stages whose clinical behavior differs. This study was undertaken to identify tumor-associated factors that might be predictive of outcome in patients with intermediate stages who will benefit the most from postsurgical adjuvant therapy. Seventy patients with stage II and III colorectal cancer were assessed for DNA index, S-phase fraction, p53 expression, and Ki-67 index. Tumor recurrence was analyzed by means of nonparametric tests and Cox proportional hazard models incorporating standard clinical and pathologic criteria. Of the four prognostic markers evaluated, Ki-67 index was significantly associated with disease recurrence (P = 0.02), whereas DNA index, S-phase fraction, and p53 expression were not. After stratification by tumor stage, significant associations between Ki-67 index and disease recurrence were retained in stage II tumors (P = 0.01) but not in stage III tumors (P = 0.23). Cox proportional hazard regression analysis indicated that among stage II patients, those with a Ki-67 index >45% were associated with 6.5 times greater risk for disease recurrence than those with a Ki-67 index >/=45%. It was concluded that an elevated Ki- 67 index is associated with an increased risk of tumor recurrence in stage II colorectal cancer.  相似文献   
148.
JJ Meehan  WD Hardin  KE Georgeson 《Canadian Metallurgical Quarterly》1997,32(7):1045-7; discussion 1047-8
Fecal incontinence is a devastating problem for school-aged children and adults. Medical and biofeedback therapies are unsuccessful in most patients who have severely defective internal and external sphincters. Continued fecal incontinence frequently leads to social isolation and withdrawal. Gluteus maximus augmentation of the sphincter mechanism is one surgical method for treating fecal incontinence. The authors present their results with gluteus maximus augmentation of the anal sphincter and describe patient selection criteria. From 1992 through 1996, seven patients underwent gluteus maximus augmentation of the anal sphincter for fecal incontinence. Six of these patients were children 5 to 6 years of age who had major deficiencies of their anorectal sphincter demonstrated by manometry. One patient was a 56-year-old adult woman who had acquired idiopathic fecal incontinence. Four of the six children (67%) had imperforate anus and two had cloacal anomalies (33%). The augmentation was performed in three stages. A sigmoid-end colostomy with a Hartman's pouch was followed 1 month later by rotation of a portion of the gluteus maximus for anorectal sphincter augmentation. A colostomy take down was performed 2 to 4 months later. All patients underwent dilatation after sphincter augmentation and were taught muscle exercises for using their neosphincter during the period before colostomy take down. Four of six children and the adult are continent postoperatively (71%). Both patients who remain incontinent are unable to sense rectal distention clinically or on anal manometric analysis but have excellent voluntary sphincter tone. Fecal incontinence can be successfully treated with gluteus maximus augmentation in carefully selected patients. Patients unable to sense rectal distension are unlikely to benefit from this procedure. The presence of a rectal reservoir and a skin-lined anal canal also appear to be important in attaining fecal continence.  相似文献   
149.
This study assesses the reliability of a self-reported health questionnaire completed by 413 subjects aged 25-74 yr in the Erie County Periodontal Disease (ECPD) Study. Specific questions on general and oral health conditions were completed by each subject during a first visit and at a follow-up examination 2 yr later, and the two compared. Results showed that the overall measure of agreement between the two visits is substantial (average kappa, kappa = 0.80). Variation by gender and age were minimal. Questions regarding allergy to medications, oral treatment, reason for tooth extraction, health symptoms and history of systemic diseases exhibited high levels of agreement (kappa ranged from 0.71-0.90). Information on vitamin and mineral intake yielded kappa = 0.63. Oral conditions scored the lowest but were still acceptable (kappa = 0.57). These findings indicate that there were no significant discrepancies in self-reported responses to the health questionnaire used in the ECPD Study. Although the information provided by the subject may not be as accurate as compared to laboratory testing, it is nevertheless a reliable source of information which can be utilized cost-effectively in research studies.  相似文献   
150.
Experiments are reported on the variations in moisture absorption properties of an epoxy resin produced by sudden changes in temperature. Where the temperature change occurred when only a little water had been absorbed, the change in moisture absorption was determined by the change in diffusivity. Where a temperature change occurred when near saturation, a reverse thermal effect was observed. An attempt has been made to understand the results in terms of thermodynamics. Results obtained for the swelling changes accompanying sudden changes in moisture content suggest that it is the more tightly bound water in the polymer which takes part in the reverse thermal effect.  相似文献   
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