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排序方式: 共有4913条查询结果,搜索用时 15 毫秒
11.
Jan E. Zejda Thomas S. Hurst Ernest M. Barber Charles Rhodes James A. Dosman 《American journal of industrial medicine》1993,23(5):743-750
A cross-sectional survey on respiratory health in swine producers showed that 30% of 301 examined men usually used a dust mask when working inside a barn. They did not differ significantly from dust mask nonusers in respect to respiratory symptoms and lung function. This analysis was undertaken to determine whether the respiratory health of dust mask users was associated with reasons why they had started individual respiratory protection. The subjects were recontacted in order to identify those who started using a mask to deliberately prevent symptoms (42 men) and those who started protection because of pre-existing respiratory symptoms (44 men). Not unexpectedly, betweengroup comparisons of respiratory symptoms and lung function suggest that swine producers who wear dust masks for preventive purposes have better respiratory health than those who wear dust masks because of symptoms or those who do not use individual respiratory protection. The individual reasons for starting dust mask usage should be examined among potential determinants of the outcomes of prospective studies which can then provide more valid assessment of the effect of individual respiratory protection. © 1993 Wiley-Liss, Inc. 相似文献
12.
Functional and structural characteristics of the glycosaminoglycans of the bladder luminal surface 总被引:7,自引:0,他引:7
The glycosaminoglycan layer of bladder has been proposed to play a crucial role in protecting the bladder from harmful substances in urine. Rats were partially cystectomized to determine whether bladder glycosaminoglycans are routinely eluted from the bladder surface in detectable quantities. Cystectomy produced no detectable qualitative or quantitative changes in excreted GAG thereby showing that most urinary glycosaminoglycan originates in the kidney and not from the bladder. Damaging the glycosaminoglycan layer by a dilute acid wash, however, leads to a consistent decrease in the output of urinary GAG which recovers to normal at the same rate as the layer regenerates. This suggests that the newly exposed sites tightly bind urinary GAG. We suggest that such binding may be a component of the normal physiological defense mechanism of the bladder. The bladder glycosaminoglycan layer was isolated, dilute acid being used to elute ionically-bound material and brief trypsinization to elute intercalated proteoglycans from the luminal surface. The GAG from the luminal surface, which was present at a density of one chain per 50 nm.2 of bladder surface, was quite different in composition from that isolated from the whole bladder. 相似文献
13.
A E Merfeld A R Mlodozeniec M A Cortese J B Rhodes J B Dressman G L Admidon 《The Journal of pharmacy and pharmacology》1986,38(11):815-822
An open crossover study of the absorption of alpha-methyldopa has been conducted in normal healthy adult male volunteers in whom a triple lumen perfusion tube had been placed. Three volunteers were perfused on separate occasions with 0.1 mM alpha-methyldopa at pH 4.5, 6.0 and 7.4. Three other volunteers were perfused on separate occasions with 0.1, 1.0 and 10 mM alpha-methyldopa at pH 6.0. Two additional subjects were perfused with 0.1 mM alpha-methyldopa at pH 6.0. Absorption was not a linear function of concentration above 1 mM alpha-methyldopa. There was also a weak trend toward greater absorption near pH 6.0. At higher concentrations of drug in the perfusion solution (10 vs 1 mM), the free fraction of alpha-methyldopa in plasma samples was increased significantly. Thus, although absorption of alpha-methyldopa is more efficient at lower concentrations, bioavailability may not be substantially enhanced due to increased sulphation in the gut wall. Comparison of permeabilities with previous results from our laboratories suggests the rat is a good model for predicting the behaviour of alpha-methyldopa after its oral administration to man. 相似文献
14.
Erinn T Rhodes Jonathan A Finkelstein Richard Marshall Carole Allen Matthew W Gillman David S Ludwig 《Ambulatory Pediatrics》2006,6(2):110-114
OBJECTIVE: The American Diabetes Association (ADA) recommends screening children at risk for type 2 diabetes with a fasting plasma glucose test or an oral glucose tolerance test. The purpose of this study was to describe attitudes, barriers, and practices related to type 2 diabetes screening in children among pediatric clinicians. METHODS: Pediatricians, nurse practitioners and physician assistants from a multispecialty, group practice in Eastern Massachusetts completed a mailed survey. To assess screening practice, three vignettes were presented representing pediatric patients with low, moderately high, and high risk for type 2 diabetes. The moderately high-risk and high-risk patients met ADA criteria for screening. ADA-consistent practice was defined as only screening the moderately high-risk and high-risk patients; lower-threshold practice was defined as also screening the low-risk patient; and higher threshold practice was screening only the high-risk patient. RESULTS: Sixty-two of 90 clinicians responded (69%). Based on intent to screen in the 3 vignettes, 21% of respondents reported ADA-consistent screening practice, 39% lower-threshold, and 35% higher-threshold screening practice. Five percent had incomplete or nonclassifiable responses. Many clinicians ordered screening tests other than those recommended by the ADA; few (< or =8% in any vignette) ordered only an ADA-recommended test. Preferences for nonfasting tests were influenced by nonmedical factors such as access to or cost of transportation. Inadequate patient education materials and unclear recommendations for appropriate screening methods were the most frequently reported moderate/strong barriers to screening. CONCLUSIONS: Most respondents reported type 2 diabetes screening practices that differed from current ADA recommendations. Our findings suggest that type 2 diabetes screening tests must be practical for clinicians and patients if they are to be used in pediatric practice. Further study of the benefits and cost-effectiveness of type 2 diabetes screening in children is warranted to clarify the role and optimal methods for screening in pediatric primary care. 相似文献
15.
There are several areas of overlap between gastroenterology and rheumatology, some related to the side effects of drugs but others related to the similarities in probable pathogenic mechanisms and treatments. This is best illustrated by comparison between inflammatory bowel disease and rheumatoid arthritis-conditions of uncertain aetiology that are due to a combination of genetic and environmental factors and are associated with chronic inflammation in the absence of any clearly recognisable pathogen. Medical research is increasingly specialised but careful comparison of the relevant gastroenterological and rheumatological literatures suggests several common areas that are worthy of greater attention than they are currently receiving. These could include studies to address the following questions: (1) What are the functional and antigen-binding differences of the HLA class II alleles that are differently associated with rheumatoid arthritis and ulcerative colitis? (2) Why are both Crohn's disease and rheumatoid arthritis associated with smoking, yet, with one condition (Crohn's disease) increasing recently in incidence and the other (rheumatoid arthritis) becoming less common? (3) Which genetic and/or environmental factors distinguish the Turkish patients with HLA-B51-associated Behcet's disease who tend not to develop colitis and the Japanese patients with HLA-B51-associated Behcet's disease who develop colitis? (4) Is pANCA directly involved in the pathogenesis of ulcerative colitis-given evidence of its direct involvement in the pathogenesis of vasculitis? (5) Given the arguably greater similarity between rheumatoid arthritis and ulcerative colitis than with Crohn's disease, is etanercept effective in ulcerative colitis? (6) Do the very different risks of cancer in chronically inflamed colon and inflamed joints imply that cancer development requires both NFkappaB activation, to inhibit apoptosis, and the presence of agents, such as bacteria, to initiate DNA damage? 相似文献
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n = 62, p < 0.05), emergent CEA (n= 2, p= 0.01), and need for postoperative anticoagulation (n= 2, p= 0.01). Only 56 (15%) of patients had indications for ICU admission, 57 (16%) would have been admitted to an EKG-monitored
nursing unit, and 252 (69%) would have been admitted to a standard nursing unit. Immediate admission to the ICU after CEA
is indicated for patients undergoing emergent CEA, those requiring anticoagulation postoperatively, those with intraoperative
stroke or major cardiac complication, and possibly those with chronic renal failure. All other patients should be admitted
to the RR. Patients experiencing stroke, major cardiac events, significant wound hemorrhage, or reintubation in the RR, and
those requiring vasoactive medication more than 3 hours after surgery should be transferred to the ICU. Patients with indications
of cardiac disease within 6 months prior to CEA but no indications for ICU admission may be discharged from the RR to an EKG
monitored unit. All others may be discharged to a standard nursing unit. 相似文献