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The effect of lysozyme-inactivation on L(+)-lactic acid (LA) production in dental plaque suspensions was evaluated. From 10 children 24-h plaque was collected and lysozyme activity inhibited by addition of goat antiserum to human lysozyme. Acid production was stimulated by addition of glucose. The results showed significantly increased LA levels (50-150%) in lysozyme-inactivated plaque suspensions from 8 of the subjects compared to untreated controls. The increase in acid production activity was not related to plaque lysozyme levels. The findings indicate that the presence of lysozyme may be limiting on acid production in the early dental plaque. 相似文献
3.
Human exposure to 3-carene by inhalation: toxicokinetics, effects on pulmonary function and occurrence of irritative and CNS symptoms 总被引:5,自引:0,他引:5
Terpenes, especially 3-carene, may irritate the skin and mucous membranes and prolonged exposure may result in allergic contact dermatitis or chronic lung function impairment. The toxicokinetics of 3-carene were studied in human volunteers exposed by inhalation (2 hr 50 W) in an exposure chamber on three occasions. The exposure concentrations were approximately 10, 225, and 450 mg/m3 3-carene. The relative pulmonary uptake was high, approximately 70% for the higher exposure levels. Total uptake increased linearly with increasing exposure. The blood clearance of 3-carene observed in this study, 0.9 liter.kg-1.hr-1, indicates that 3-carene is fairly readily metabolized. About 3% of the total uptake was eliminated unchanged via the lungs while less than 0.001% was eliminated in the urine after the end of exposure. A long half time in blood was observed in the terminal phase which indicates a high affinity to adipose tissues. A statistically significant divergence between ratings of irritation during the high exposure level and during the medium and control levels was observed. The difference in airway resistance after exposure to a high concentration of 3-carene compared to control level was not significant (P = 0.02). 相似文献
4.
Chronic intestinal pseudo-obstruction: manifestations, natural history and management 总被引:2,自引:0,他引:2
v. stanghellini r. f. cogliandro r. de giorgio g. barbara b. salvioli & r. corinaldesi 《Neurogastroenterology and motility》2007,19(6):440-452
Chronic intestinal pseudo-obstruction (CIPO) is a rare pathological condition characterized by a marked derangement of gut propulsive motility mimicking mechanical obstruction, in the absence of any lesion occluding the gut lumen. This disease is often associated with a disabling and potentially life-threatening complications and is still too often unrecognized even in referral centres. As a result, patients receive neither appropriate care nor recognition of their severe health condition. Medical and surgical therapies are often unsatisfactory and long-term outcome turns out to be poor in the vast majority of cases. This article focuses on the main clinical features, the management and long-term outcome of patients affected by CIPO, with particular emphasis on those aspects which remain a matter of debate. 相似文献
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6.
m. f. américo r. b. oliveira † f. g. romeiro ‡ o. baffa § l. a. corá ¶ & j. r. a. miranda ¶ 《Neurogastroenterology and motility》2007,19(10):804-811
Abnormal intragastric distribution of food (IDF) and a phasic contractility in the proximal stomach have been related to dyspeptic symptoms. Thus, the behaviour of the stomach and the proximal region, in particular, continues to attract attention and demand for reliable and comfortable techniques. The aims of this study were to employ AC Biosusceptometry (ACB) and scintigraphy to evaluate IDF and gastric motor activity in humans. Fifteen healthy volunteers ingested 60 mL of yogurt containing 2 mCi of 99mTc and 4 g of ferrite. Each volunteer had gastric motility and IDF evaluated twice on separate days; on one occasion by ACB and another by scintigraphy. Digital signal processing was performed in MatLab (Mathworks Inc., Natick, MA, USA). Results were expressed as mean +/- SD. Similar results of distal accumulation time (P < 0.001) were obtained for scintigraphy (6.93 +/- 3.25 min) and for ACB (7.04 +/- 3.65 min). Fast Fourier Transform revealed two dominant frequencies (P > 0.9). Besides the well-know frequency of 3 cpm, our results showed identical frequencies in proximal stomach recordings (P < 0.001) for scintigraphic (1.01 +/- 0.01 cpm) and ACB (0.98 +/- 0.06 cpm). In summary, our data showed that scintigraphy and ACB are promising techniques to evaluate several aspects of gastric motility. Moreover, ACB is non-invasive, radiation-free and deserves the same importance as conventional methods for this kind of analysis. 相似文献
7.
C. Dahlf 《Clinical cardiology》1991,14(2):97-103
Quality of life is often considered to equate how the medical treatment is subjectively perceived by the patient, but ought to include the total impact of the disease/treatment on the patient's emotional, physical, and social well-being. Recently, a proposal for a generally applicable definition of quality of life in health care was put forward. This definition includes general well-being, health, and welfare (external factors), as three fundamental components, and the definition is based on both objective and subjective judgments. General well-being is exclusively and expression of the individual's subjective experience and is based on his or her own qualitative evaluation of well-being in relation to condition, treatments, and experiences. Health is according to the proposed definition, judged both objectively (signs) and subjectively (symptoms). Apart from health and well-being, there is also reason to include objectively registrable factors at the welfare level (external factors) such as the consumption of medicines, number of days in hospital, length of sick leave, need of in-home care, etc. This review is an attempt to elucidate the effects of antihypertensive pharmacotherapy on the patient's general well-being. The topic will be discussed from several points of views (e.g., aims of antihypertensive treatment, occurrence of symptoms in the population, compliance with prescribed treatment, symptom inventories, the concept of quality of life. 相似文献
8.
Bay. LandesberufsG für die Heilberufe 《MedR Medizinrecht》2003,21(8):477-480
Ohne Zusammenfassung 相似文献
9.
Prejunctional alpha-adrenoceptor-mediated inhibition of norepinephrine release in blood-perfused skeletal muscle in situ 总被引:1,自引:0,他引:1
The influence of alpha-adrenoceptor antagonists on the overflow of endogenous norepinephrine (NE) and vasoconstrictor responses elicited by sympathetic nerve stimulation (1-4 Hz, 2 min) was investigated in desipramine-pretreated canine blood-perfused skeletal muscle in situ. The nonselective alpha-adrenoceptor antagonist phentolamine enhanced stimulation-evoked NE overflow and reduced vasoconstrictor responses concentration-dependently. Similar effects were obtained with phenoxybenzamine (irreversible alpha-adrenoceptor antagonist). Desipramine pretreatment attenuated the enhancement of stimulation-evoked NE overflow produced by phenoxybenzamine, indicating that phenoxybenzamine also inhibits neuronal uptake. The enhancement by phenoxybenzamine was independent of the stimulation frequency, suggesting a similar engagement of prejunctional alpha-adrenoceptor-mediated inhibition of transmitter release over the frequency range studied here. The alpha 2-selective adrenoceptor antagonist yohimbine enhanced nerve stimulation-evoked NE overflow at concentrations similar to those required to antagonize vasoconstrictor responses to exogenous NE; 10-fold higher concentrations were required, however, to antagonize nerve stimulation-induced vasoconstriction. The concept of a quantitatively important prejunctional alpha 2-adrenoceptor-mediated feedback inhibition of NE release in vivo is supported by our findings in the skeletal muscle vasculature. Postjunctional alpha 2-adrenoceptors appear to be preferentially activated by circulating catecholamines but also seem to be involved in the nervous control of vascular tone. 相似文献
10.
B Lindel?f 《Der Hautarzt; Zeitschrift für Dermatologie, Venerologie, und verwandte Gebiete》1989,40(1):4-7
Grenz rays (ultrasoft X-rays, Bucky rays) have been used in the treatment of benign skin disorders for more than 60 years. The mechanism of action, the clinical effect and the potential carcinogenic effect have remained largely unknown, and many of the reported studies are now obsolete. Recent studies of both the clinical and the basic characteristics of grenz rays have shown that the number of Langerhans' cells decreases in the human epidermis after treatment and that grenz rays can suppress the expression of nickel allergy in sensitive individuals. Also, very good results have been reported in the treatment of psoriasis of the scalp. A large-scale study involving more than 14,000 patients has shown that grenz ray therapy cannot be excluded as a risk factor in the development of non-melanoma skin tumors, but this risk factor is small and can virtually be disregarded when certain therapy recommendations are followed. This article is an attempt to summarize the present knowledge of grenz ray therapy. 相似文献