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1.
Preoperative hair removal by a depilatory cream was compared with routine shaving. Although the incidence of wound infection was similar in both groups, cream depilation was found to be better. It was effective, atraumatic, non-toxic, and could be self-administered. Furthermore, it could be used safely on granulating wounds and did not support bacterial growth. Depilation was associated with a significant reduction in skin surface bacteria and proved to be cheaper than shaving. 相似文献
2.
Peritubular dentine is a mineralised deposit formed centripetally in the dentine tubules with advancing age, so that the tubular diameter is smaller in teeth from older persons. The aim of the present study was to investigate the relationship between age in humans and the amount of peritubular dentine and the extent of the consequent obliteration of the tubules, and to find out whether this relationship was strong enough to be used as a parameter for age estimation. Fifty mandibular central and lateral human incisors were ground on the lingual aspect of the root and examined in a scanning electron microscope (SEM). The number of open tubules was counted and the diameter of the tubules measured both before and after etching with 35% orthophosphoric acid. The difference in the number of tubules in unetched and etched specimens was taken to be the number of occluded tubules, and the difference in radii before and after etching to be the thickness of peritubular dentine. The results did not demonstrate a significant relationship between age and the reduction in the number of tubules. One explanation might be that a certain age has to be reached before obliterated dentine tubules can be observed. The correlation between age and the thickness of peritubular dentine was not significant in teeth extracted because of periodontal disease, so these teeth were excluded from the regression analysis with age as the dependent variable. Only the thickness of peritubular dentine was included in the regression (r=0.69); this factor was a better indicator of age than the tubular diameter, but not so closely related to age that it can be recommended for general use in forensic and archaeological age estimations. 相似文献
3.
M Koltai G Blazsó A Ottlecz E Minker 《Acta physiologica Academiae Scientiarum Hungaricae》1979,54(3):287-293
The insulin-induced sensitization to generalized and local anaphylactoid reaction evoked by dextran was studied in Sprague-Dawley CFY rats. The generalized reaction was shown to be potentiated by insulin given subcutaneously in a dose-related manner. The minimum effective dose was as low as 0.04 U/kg. When this dose was injected intravenously, a marked but short-lived potentiation was observed. The insulin response could be elicited throughout the whole year. The local oedema induced by subplantar injection of dextran was found to be much less sensitive to insulin. Potentiation was observed during the period from March to October, while in the intermediate months, no such effect could be seen. The seasonal refractory state to insulin was abolished by bilateral adrenalectomy, and daily pretreatment of the rats with insulin for several days. Actinomycin D prevented the restorative effect of insulin pretreatment. Sensitization by a single insulin dose to both systemic and local dextran was suppressed in rats older than 6 months, and the refractoriness was in part reversed by adrenalectomy. 相似文献
4.
Several new methods for detection of bacteriuria were studied to evaluate their usefulness as screening procedures. A new filter paper device incorporating dehydrated media and tetrazolium was found to be reliable when compared with the standard pour plate method in the laboratory and with the dip-slide method in a field test. It failed to detect yeasts and slowly growing streptococci. Antibiotics blocked the test when susceptible organisms were present. An agar-cup method was found to be quite reliable, but could be improved by use of differential media. The Griess test was confirmed in a small trial to be highly specific when used in conjunction with a first morning specimen, but of little value with random specimens. Phenzopyridine was found to give false positive reactions. The subnormal glucose test, although highly sensitive and specific, gave too many false positive tests to be useful other than as a screening method. 相似文献
5.
The results of a Monte Carlo simulation of laser beam propagation in turbid media are presented. The study was performed to determine whether using a focused beam or multiple beams instead of a single collimated beam could improve subsurface laser energy delivery in biological tissue. A parametric study was carried out to determine both the laser fluence at a target depth and the ratio of fluence at the target over surface fluence as a function of tissue properties and the mode of energy delivery. It was found that the reduced scattering coefficient was the primary determinant as to whether multibeam or focused beam delivery could be effective. A focused beam was found to be extremely effective in increasing fluence at the target if the dimensionless reduced scattering coefficient was less than 2. The delivered fluence, however, was found to be extremely sensitive to tissue properties. A five-beam laser system was found to be less effective at increasing fluence at the target than a focused beam; but the fluence delivered by a five-beam system was far less sensitive to tissue properties, thereby making accurate dosimetry more feasible. 相似文献
6.
There are currently several debates taking place in palaeoanthropological circles in which the issue of sexual dimorphism
is crucial. During the 60th Jubilee of the discovery of the TaungAustralopithecus skull, the authors concurred that much of the debate was due to differences in perception concerning dimorphism, and it was
suggested that a study session dealing principally with sexual dimorphism in Primates should be organised with a view to determining
what, if anything, could be observed in extant primates that might be utilised for determining the existence of dimorphism
in fossil species. An advertisement was placed in the Journal of Human Evolution, calling for papers. Response was encouraging,
suggesting that there was indeed a need for such a meeting, which was organised to take place late in November in Italy. Seventeen
scientists sent abstracts, but due to the rather short notice, several were unable to attend the meeting. Nevertheless, papers
were received and read at the meeting which form the basis for this issue of the Journal of Human Evolution. What remains
to be done now, is for a second meeting to be organised at which the findings of the first meeting can be extended backwards
in time into the fossil record. 相似文献
7.
Heinonen-Tanski H Kiuru T Ruuskanen J Korhonen K Koivunen J Ruokojärvi A 《Bioresource technology》2005,96(2):247-252
Thermophilic aeration of cattle slurry and food industrial by-products was studied with the aim to improve hygienic qualities of the slurry so that it could be used as a safe fertiliser for berries to be eaten raw. We also wanted to study if the process would be energetically favourable in an arctic climate. Cattle slurry alone or with whey and/or jam waste was treated. The tests were done in a well heat-insulated reactor with a 10 m(3) volume. Temperature increases up to over 70 degrees C could be recorded in 19 days even though some processes were carried out in winter time when the ambient air temperature was less than 0 degrees C. The heat energy formed was higher than the electrical energy needed to carry out the aeration. The hygienic qualities of the aerated product were good with only minor nitrogen losses. The end product could be useful as a fertiliser and soil improving compound to increase the organic matter content of agricultural soil. Cattle slurry alone was well suited as the raw material if attaining a high temperature was the main goal. A part of slurry could be replaced with food-industrial side products. Whey waste suited better for co-composting than jam waste but the mixture of whey, jam waste, and slurry was optimal for composting. 相似文献
8.
The mechanism of transport of the tumor localizing agent, meso-tetra(p-sulfophenyl)porphine (TPPS4), was investigated in Vero and HEp-2 cells in vitro. Vero cells proved to be basically impermeable to the porphyrin, but a slow transport was observed. The uptake was linear with time and appeared to be carrier mediated, as it was strongly inhibited by cyanide or low temperature and demonstrated saturation kinetics. Transport in HEp-2 cells was more rapid and non-linear, reaching a plateau after about 2 h. Analysis of this uptake over a 20-fold range of porphyrin concentration revealed it to be biphasic. A low affinity, high capacity component appeared to be unsaturable and was unaffected by low temperature or metabolic inhibitors. This system is probably one of a passive diffusion. The high affinity, low capacity phase is probably carrier mediated. The tumor cells appear to be "leaky" to the porphyrin, with respect to the Vero cells. This may explain part of the localizing ability of TPPS4. 相似文献
9.
Ureidoglycolate amidohydrolase from developing French bean fruits (Phaseolus vulgaris [L.].) 总被引:2,自引:0,他引:2
Ureidoglycolate is an intermediate of allantoin catabolism in ureide-transporting legumes. This report describes the first purification of ureidoglycolate degrading activity (UGDA) from plant tissue in which the enzyme has been separated from urease. The enzyme from developing fruits of Phaseolus vulgaris has been purified 48-fold to give a preparation free of allantoinase and urease activity. UGDA was inhibited by EDTA while the Vmax was increased in the presence of Mn2+. The Km values for ureidoglycolate in the presence and the absence of Mn2+ were 2.0 and 5.4 mM, respectively. In the absence of Mn2+ UGDA was heat labile at 40 degrees C, but in the presence of Mn2+ the activity was stable up to temperatures of 60 degrees C. The Mr of UGDA was determined to be 300,000 by gel filtration chromatography and the pH optimum ranged from pH 7.0 to 8.5. Ammonia was determined to be the nitrogen-containing product of UGDA by a microdiffusion assay. This enzyme should therefore be described as ureidoglycolate amidohydrolase. The activity was shown to be associated with peroxisomes by fractionation of a crude extract on a sucrose density gradient. The products of ureidoglycolate degradation are glyoxylate, ammonia, and presumably carbon dioxide, which can be readily utilized by pathways of metabolism that are known to be present in this organelle. 相似文献
10.
The aim of this study was to investigate the ability of liquid loadable tablets (LLT) to be loaded with a self-microemulsifying drug delivery system (SMEDDS) containing cyclosporine (CyA). LLT were prepared by direct compression of the porous carrier magnesium aluminometasilicate and subsequently loaded with SMEDDS by a simple absorption method. SMEDDS was evaluated regarding visual appearance and droplet size distribution after dispersion in aqueous media. The developed SMEDDS was found to be similar to Neoral®. LLT were characterized before and after loading regarding weight variation, tablet hardness, disintegration time, and in vitro drug release. It was found that LLT with high porosities suitable for liquid loading and further processing could be prepared. Adding a tablet disintegrant was found to improve in vitro drug release. Additionally, the volume-based loading capacity of LLT was evaluated and found to be comparable to soft gelatin and hard two-piece capsules. Furthermore, the pharmacokinetic performance of CyA from loaded LLT was tested in two PK-studies in dogs. Absorption of CyA from SMEDDS loaded into LLT was found in the first study to be significantly lower than the absorption of CyA from SMEDDS filled into a capsule. However, addition of a superdisintegrant improved the absorption markedly. The bioavailability of CyA from SMEDDS loaded into disintegrating LLT was found in the second study to be at the same level as from capsule formulation. In conclusion, the LLT technology is therefore seen as a promising alternative way of achieving a solid dosage form from liquid drug delivery systems. 相似文献
11.
12.
An enzyme which catalyzes the reduction of methylglyoxal to lactaldehyde has been isolated and purified from goat liver to apparent homogeneity. NADH was found to be a better substrate than NADPH for methylglyoxal reduction. Stoichiometrically equivalent amounts of lactaldehyde and NAD are formed from methylglyoxal and NADH. Enzyme activity was located only in the soluble supernatant fractions of liver cells. Of the various carbonyl compounds tested, methylglyoxal was found to be the best substrate. The pH optimum of the enzyme was found to be 6.5, and Km for methylglyoxal was 0.4 mM. The molecular weight of the enzyme was found to be 89000 by gel filtration on a Sephadex G-200 column. Electrophoresis on sodium dodecyl sulfate-polyacrylamide gel revealed that the enzyme is composed of two subunits. The enzyme is highly sensitive to sulfhydryl group reagents. The inactivation by p-chloromercuribenzoate could be substantially protected by methylglyoxal in combination with NADH, indicating a possible involvement of one or more sulfhydryl group(s) at the active site of the enzyme. 相似文献
13.
N. M. HORN S. V. REDDY I. M. ROBERTS D. V. R. REDDY 《The Annals of applied biology》1993,122(3):467-479
A disease of chickpea in India, characterised by chlorosis, severe stunting and phloem browning, was shown to be caused by a geminivirus. This virus was transmitted by the leafhopper Orosius orientalis from chickpea to chickpea and several other plant species. A method for purification of this virus was devised and a polyclonal antiserum produced. The majority of the purified particles were geminate. The size of the coat protein was shown to be 32 kD and the nucleic acid was shown to be circular ssDNA of 2900 nucleotides. By immunosorbent electron microscopy this virus was shown to be unrelated to the leafhopper-transmitted geminiviruses known to infect dicotyledons such as beet curly top, bean summer death and tobacco yellow dwarf viruses. On the basis of particle morphology, leafhopper transmission, host range and serology this virus was considered to be a new, hitherto undescribed, geminivirus and was named chickpea chlorotic dwarf virus. 相似文献
14.
A cyanogen bromide fragment of beta-galactosidase from Escherichia coli with alpha-donor activity in complementation of the enzyme from mutant M15. 总被引:2,自引:2,他引:0
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Aminoethylated beta-galactosidase from Escherichia coli was cleaved by CNBr. The fragment C4a was purified by gel filtration and ion-exchange chromatography. The molecular weight of the fragment C4a was determined to be 9000 +/- 600. The N-terminal amino acid was found to be isoleucine. Qualitative examination of homogeneity was carried out by disc-gel electrophoresis. The fragment C4a was shown to be active as an alpha donor in complementation of beta-galactosidase activity in vitro with E. coli mutant M15, which has a deletion in the alpha region of the z gene. The molecular weights of complementable fractions from mutant M15 were found to be 123 000 +/- 2500 and 507 000 +/- 11 000, and of the complemented enzyme 522 500 +/- 11 400. 相似文献
15.
黄土丘陵区沙棘人工林天然化发育过程中的种间联结性研究 总被引:4,自引:0,他引:4
采用样地调查法,并通过方差分析、X2检验及共同出现百分率PC计算,对黄土高原丘陵沟壑区经过3a、8 a、13a、25a发育的沙棘群落中主要种群间联结性进行了比较研究。结果表明,灌木层的4个发育阶段,总体关联性都表现出轻微正相关。草本层中,发育3a的群落,总体联结性表现出极显著正相关,但种间关系不够稳定;发育8a 的群落,总体关联性表现出轻微正相关,种间关系不稳定;发育13a的群落,总体关联性表现出极显著正相关,负关联种对减少,种间关系逐步趋于稳定;发育25a的群落,种间关系相对稳定。表明沙棘在黄土高原丘陵区人工林天然化发育的过程中,已实现了自我更新。说明人工林只有经天然化发育过程才能实现持续利用,达到普通生态系统的服务功能。 相似文献
16.
A thin section of tooth was cemented to a microscope slide with Kodak 910 Adhesive and ground down to a thickness of approximately 6 μ The section was covered with a thin layer of dental impression material by squeezing it out under cellophane, using pressure on a second microscope slide. A channel was cut in the impression material exposing a portion of the tooth substance. The channel was covered with a coverglass enabling decalcifying solutions to be passed over the exposed area of the tooth and the section to be observed at the same time. This procedure enables sections of calcified tissue to be decalcified very slowly and the histological changes to be observed microscopically. 相似文献
17.
An enzyme which catalyzes the hydrolysis of L-prolyl-L-leucylglycinamide, the factor which inhibits the release of melanocyte-stimulating hormone, was purified 189-fold from bovine kidney in a 5% yield. The molecular weight of the enzyme on gel filtration was estimated to be 300 000 and its isoelectric point was found to be pH 4.1. The single component seen on sodium dodecyl sulphate-gel electrophoresis was estimated to have a molecular weight of 56 000, indicating that the native enzyme may be a pentamer or hexamer. The enzyme could clearly be distinguished from other prolyl-cleaving enzymes. 相似文献
18.
《Plains anthropologist》2013,58(50):297-301
AbstractTo find out whether complex statistical methods could be successfully applied to site survey data, the correlation coefficient was used to evaluate the reliability and validity of survey data gathered from Mahaska county, Iowa by means of a mailed questionnaire. It was also used to identify geographical characteristics of the sites located by the above survey. The reliability of the survey data was found to be questionable, while their validity was found to be good. Sites in Mahaska county were found to be located near rivers, at low altitudes, and on timber soil. It was concluded that the correlation coefficient can be a useful tool in working with site survey data. 相似文献
19.
Yukitake H Furusawa M Taira T Iguchi-Ariga SM Ariga H 《The Journal of biological chemistry》2002,277(47):45480-45492
20.
S C Martin 《The Biochemical journal》1989,261(3):1051-1054
Complement factor C3, the central protein of the complement system, was found to be phosphorylated both in EDTA- and heparin-anticoagulated whole blood and in coagulating blood. Complement S protein (vitronectin) was also found to be phosphorylated under these conditions. Further, purified C3 was found to be a phosphoprotein in vivo, containing 0.15 mol of alkali-labile phosphate/mol of protein. The ATP concentration in plasma was measured and found to be about 2 microM. 相似文献