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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
The two stage gravimetric technique used for the measurements of industrial aerosols, in combination with measurements of mass-related concentrations of particles in the air, provided major hygienic information on the sizes (dispersity) of the inhaled particles. The results of the measurements taken in various branches of industry, ore and alluval deposit mines clarified the fundamental properties of the particles' distribution into rough and thin fractions. An express two-stage gravimetric technique for determining ore aerosol dispersal contents was proposed, along with the technical characteristics of the USSR-produced dust counters. 相似文献
992.
We applied a specific cytochemical reaction to characterize the glycoconjugates produced by goblet and non-goblet epithelial cells of normal human conjunctiva. For this purpose we utilized the lectins, proteins of vegetal origin, which are extremely sensitive in binding glycosidic residues. In particular, we used WGA, PNA, SBA and ConA conjugated with colloidal gold as ultrastructural marker for Transmission Electron Microscopy. This technique allowed us also to perform a quantitative analysis, by counting colloidal gold particles present on mucus granules. In this way we analyzed the content both of goblet and non-goblet epithelial cells. In the former, WGA, PNA, SBA and ConA receptors, here reported in decreasing density, were present. In the latter WGA was always positive, SBA and PNA sometimes were negative, ConA was always negative. We speculate the different contribution to mucus production by these two sources may be important in evaluating tear film stability alterations occurring in those diseases in which non-goblet epithelial cell vesicles increase. 相似文献
993.
994.
R Menningen M Günther N B?nninghoff C D Stahlknecht I Kubitza J Kusche 《Agents and actions》1986,18(1-2):38-40
In the operative treatment of appendicitis the so called negative appendectomy is an important issue because of its increased morbidity. From the hypothesis that the intestinal diamine oxidase activity is a suitable marker of mucosal integrity, the distribution pattern of the enzyme in appendices histologically classified as inflamed or not inflamed was studied. Histologically apparent inflammation of the appendix was connected with a significant reduction of diamine oxidase activity. The determination of this enzymic activity may be a simple and sensitive test for mucosal inflammation of the appendix even at a very early state. This could reduce the rate of negative appendectomies and influence thereby risk-cost-benefit calculations. 相似文献
995.
Placement of the nasojejunal feeding tube under direct visual guidance using endoscopy offers an alternative method to those currently used. We found it to be a safe method easily performed by house staff. It is less burdensome than other described endoscopic techniques and does not require patient transfer or fluoroscopic facilities. 相似文献
996.
Gestational age determination based on obstetric dating criteria, early pregnancy ultrasound scans, Dubowitz examinations, and ultrasound scans performed shortly before delivery were reviewed for 69 preterm infants requiring neonatal intensive care. The last ultrasound scans underestimated gestational age by a median of 8 days, and by 2 weeks or more in 20 of the 69 cases, as opposed to best dating criteria. Ultrasonic fetal weight estimation was more accurate, but erred by more than 20% in 10% of cases. When obstetric decisions regarding preterm neonates must be made without prior information regarding gestational age, late ultrasound findings must be applied with extreme care. 相似文献
997.
PURPOSE: To examine longitudinal changes in mood and empathy over the course of the internal medicine residency. METHOD: The authors conducted a cohort study of 61 residents who completed the Profile of Mood States (POMS) and the Interpersonal Reactivity Index (IRI) at six time points during their internal medicine residency at a university-based program. (POMS was administered five times, and IRI was administered six times.) The main outcomes measured were trends in mood disturbances and multiple domains of empathy over the three-year residency, and comparisons to norms. RESULTS: Response rates varied from Time 1 to Time 6 (98%, 72%, 79%, 79%, 94%, and 95%, respectively). Interns had better scores on four POMS subscales: Depression-Dejection (p = .0031), Anger-Hostility (p < .0001), Fatigue-Inertia (p < .0001), and Vigor-Activity (p < .0001) compared with later administrations, especially midinternship. By the end of residency all POMS scores were returning towards baseline (effects sizes in the .20 s), but only depression was no longer significantly different. IRI scores showed the decline in Empathic Concern remained over residency whereas Personal Distress peaked midinternship year but approached baseline at the end of residency. Compared with the general population, the graduating residents were less tense, depressed, and confused. Personal Distress was significantly lower than the norm group. CONCLUSIONS: Internal medicine residency presents challenges resulting in common mood disturbances. Although graduating residents appear to be better off than the population norms, some domains of their mood disturbances and empathy never fully recover from their internship year. 相似文献
998.
M. G. Ismailova 《Pharmaceutical Chemistry Journal》2007,41(5):281-284
A new technology is developed for the production of activated charcoal (AU-L) tablets from cotton lignin, a readily available
local raw plant material. The physicochemical and technological properties of the parent substance (powder) have been studied
and the optimum composition of tablets has been determined. The best technological characteristics of both the initial mass
and the ready-to-use tablets are achieved for the composition involving a 3% methyl cellulose gel as a binding component and
microcrystalline cellulose as a filler. The qualitative characteristics of AU-L tablets have been studied and their sorption
capacity has been determined. The new technology will be implemented at the Tashkent Pharmaceutical Plant (Uzfarmprom Company).
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 5, pp. 49–52, May, 2007. 相似文献
999.
1000.
The most frequent pathogens causing bacterial meningitis in Germany are Neisseria meningitidis, Streptococcus pneumoniae, Borrelia burgdorferi, Listeria monocytogenes and staphylococci. Since immunization against Haemophilus influenzae has become a routine vaccination procedure, this pathogen no longer plays a significant role in the etiology of bacterial meningitis. A number of pilot studies have indicated that selected PCR methods most probably represent the future etiological diagnosis of bacterial meningitis. The easiest and most rapid diagnostic method is, however, still a simple gram stain preparation. In fatal cases that ran a peracute course, especially in the Waterhouse-Friderichsen syndrome, only increased congestion of the surface of the brain is detectable at autopsy. In such cases, there is hardly any histological evidence of an inflammatory reaction of the leptomeninges. In cases of purulent meningitis, in addition to the typical infiltration of the subarachnoid space with abundant granulocytes, after some days of illness there is a wide-spread histomorphological picture of pathological alterations with fibrinoid vessel wall necroses, thromboses, ventriculitis, infarctions as well as venous and arterial vasculitis. The breakdown of the integrity of the blood-brain-barrier in bacterial meningitis is obviously due to a separation of intercellular tight junctions of the endothelium of the capillaries of the leptomeninges. The cause of death in meningitis, depending on the severity and duration of a concomitant sepsis, is an increase in intracranial pressure that leads to a circulus vitiosus (via a reduced central perfusion associated with metabolic acidosis) with cerebral vasodilatation. This is followed by an additional rise of intracranial pressure and finally a reduced cerebral blood supply and central dysregulation. The medico-legal expert is occasionally confronted with this topic against the background of a possible misjudgement of the disease due to insufficient diagnostics or delayed diagnosis and in the light of a posttraumatic or nosocomial origin of the illness. 相似文献