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1.
Urine washing is a common behavior in strepsirrhine and platyrrhine primates, but its function is still poorly understood. We investigated the factors influencing urine washing behavior in 2 captive groups of tufted capuchins (Cebus apella). Urine washing was affected by group membership (subjects in the 2 groups urine washed at different rates) and was negatively related to age, but was not influenced by sex or dominance rank. Females urine washed less when in estrus, and the presence of an estrous female did not affect male urine washing behavior. We observed independent effects of diurnal and climatic variables on urine washing. Tufted capuchins urine washed more at midday and under conditions of higher temperatures and lower relative humidity. Both of the latter effects were evident only at the lowest temperatures (5?C20°C). Our results indicate that urine washing is sensitive to multiple influences, and that hypothetical communicative or thermoregulatory functions do not fully account for its occurrence.  相似文献   

2.
Urine washing (UW) is taxonomically widespread among strepsirhines and platyrrhines, yet its functional significance is still unclear. We used 2274 h of focal follows of 35 adult and subadult wild white-faced capuchins (Cebus capucinus) to test 1) the intergroup signaling, intragroup social signaling, and thermoregulatory hypotheses for UW and 2) the hypothesis that individuals sniff each other's urine and other traces to gather socially significant information. Males engaged in significantly more UW than females. All 5 α-males engaged in more UW than subordinate males did, including 4 α-males that increased their UW rate above that of their male groupmates after their rise to α rank. Males engaged in significantly less UW while in view of other males than at other times. Male-male sniffing rates do not correlate with either aggression rate or dominance rank distance. Urine washing rates did not increase while subjects were in parts of their home range where more intergroup encounters occurred. Urine washing rates were highest early in the morning and late in the afternoon, presumably when temperatures were coolest. The data do not support either the thermoregulatory or social signaling hypothesis. We suggest that experiments with captive capuchins are necessary to resolve the issue of the function of urine washing in the taxon.  相似文献   

3.
Our knowledge of the traits possessed by extraintestinal isolates of Escherichia coli, necessary for growth and survival in urine, is limited. To identify such determinants, transposon (TnphoA′1,4) mutant libraries of a clinical isolate (CP9) were generated and screened for derivatives exhibiting decreased growth in urine in vitro, and for mutants with active lacZ fusions that were induced in urine relative to laboratory medium. Using this approach we identified two genes, guaA (CPA24) and argC (CPI-1), which were previously unrecognized as being important for growth in human urine. Unexpectedly, not only does CPA24 (guaA) not grow in human urine in vitro, but it is sensitive to its effects, undergoing a 2–3 log loss of viability over 6 h. By contrast, CPA24 neither grows nor is killed in M9 minimal medium and artificial urine. Therefore, we postulate that lack of guanine or its derivatives in urine, and the inability of CPA24 to synthesize these compounds de novo, prevents CPA24 from synthesizing other guanine (or derivatives)-dependent products that are critical for growth and survival in urine. Although it seems logical that decreased growth in urine in vitro should correlate with diminished urovirulence, this concept was tested by challenging mice with CPA24 in vivo in a mouse model of urinary tract infection (UTI). Indeed, CPA24 was found to be significantly less virulent compared with its wild-type parent CP9. CPI-1(argC) was identified because of the significant induction of its argC::lacZ fusion in urine. Subsequent testing in urine demonstrated that its growth was significantly diminished in all urine samples tested (four females, three males). Polyamine synthesis is dependent upon, in part, the arginine biosynthetic pathway. Therefore, we tested whether the induction of argC in urine and/or the decreased growth of CPI-1 was a result of low levels of polyamines or arginine in urine. The results suggest that low levels of arginine, but not polyamines, in human urine are responsible. When tested in vivo in the mouse model of UTI, CPI-1 was also found to be significantly less virulent than CP9. In summary, we have established that guaA and argC are the first genes, which we are aware of, that have been shown to contribute to the growth of E. coli in urine in vitro and both have diminished urovirulence in vivo. These results support the concept that urine can be used in vitro as a screening tool to identify urovirulence traits.  相似文献   

4.
A non-covalent molecularly imprinted polymer (MIP) was synthesised using naproxen (a non-steroidal, anti-inflammatory drug (NSAID)) as a template molecule. The MIP was chromatographically evaluated to confirm the imprinting effect, and was then applied as a selective sorbent in solid-phase extraction (SPE) to selectively extract naproxen. After this study, the MIP was used to extract naproxen from urine samples; it was demonstrated that by applying a selective washing step with acetonitrile (ACN) the compounds in the sample that were structurally related to naproxen could be eliminated.  相似文献   

5.
The bacteriological profile of a chicken hatchery in Jamaica was examined. The bacterial numbers in each room of the hatchery and the effect of washing with disinfectant on the bacterial population were determined. A representative number of the bacterial isolates before and after washing the hatchery was identified. The results indicate that, while washing with quaternary ammonium compounds did not affect the Gram-negative bacteria, the number of Gram-positive bacteria was significantly decreased. Bacteria of the genera Pseudomonas, Plesiomonas and Enterobacter were predominant in the post-washing flora. The water used to wash the hatchery was contaminated and therefore a possible source of contamination.  相似文献   

6.
A number of experiments on the effect of wound washing on the development of crown gall were made varying the following factors: Host species; bacterial strain; non-washing versus washing for different periods; sterile versus inoculated wound; time of inoculation. Washing did not have a recognizable effect on the healing of sterile wounds. Neither did it seem to overcome incompatibility between host and bacterial strain. Washing promoted tumor growth significantly under the following conditions: Vicia faba inoculated with T37 20 hours after washing for 1 hour; Helianthus annuus inoculated with B6 immediately after washing for 2 hours.  相似文献   

7.
Cell wall preparations of Convolvulus callus were found to contain α-glucosidase activity, the bulk of which could be solubilized by solutions of high ionic strength. Callus tissue incubated in 0.5 M KC1 released α-glucosidase activity into the washing medium as distinct from tissue incubated in 1.0 M sorbitol. The wall-bound activity of KCl-treated tissue was found to be less than that of sorbitol-treated tissue, while the difference between both activities proved to be equal to the enzyme activity found in the washing medium of KCl-treated tissue. Since no trace of cell leakage was observed, it is concluded that α-glucosidase activity is located at the cell surface. The level of this surface-located enzyme was not affected by the presence of maltose in the nutrient medium.  相似文献   

8.
A high-performance liquid column chromatographic technique is reported for the analysis of some tryptophan and phenylalanine acid metabolites in the urine. An acidified and NaCl-saturated urine sample is loaded on to a C15-bonded silica microcolumn. After washing the microcolumn with clean and deionized water, the metabolites of interest are selectively extracted by successive elutions with organic solvents of variable polarity. Acids are eluted first and the neutral compounds with the next fraction. Basic compounds and other neutral substances of higher polarities were eliminated during the washing procedure.The chromatography was performed in the straight-phase isocratic elution mode utilizing 5-μm silica-gel columns loaded with a triethanolammonium perchlorate—perchloric acid aqueous solution. The separations achieved have permitted the application of the chromatographic technique to the analysis of urinary metabolites with acceptable accuracy.  相似文献   

9.
It has been recognized recently that the standard field technique for the diagnosis of urinary schistosomiasis, urine filtration using reusable polyamide mesh filters, may give false-positive findings because filters cannot be washed adequately in all circumstances. In this study the alternative filtration method using polycarbonate membrane filters was tested, and the same problem existed. A variety of more vigorous washing procedures was field tested with the conclusion that polycarbonate filters can be washed adequately for reuse by a simple procedure that includes boiling for 5 min in tap water prior to washing with detergent.  相似文献   

10.
Context: Postexercise urine lactate may be a novel biomarker of lactate production capacity during exercise.

Objective: To evaluate the reliability and utility of the urine lactate concentration after maximal swimming trials between different training protocols (6?×?50?m and 3?×?100?m) and training states (active and nonactive swimmers).

Materials and methods: Lactate and creatinine were determined by spectrophotometry in blood and urine.

Results: Blood and urine lactate concentrations were correlated in-between training protocols and in participants of different training states. The reliability of the urine lactate concentration was moderate for one of the training protocols and good or moderate for the two training states. Additionally, it was lower than that of the blood lactate concentration, and did not improve after normalizing to the urine creatinine concentration.

Discussion and conclusion: Although promising as a biomarker of lactate production capacity, urine lactate requires further research to improve its reliability.  相似文献   

11.
A selective semi-automated solid-phase extraction (SPE) of the non-steroidal anti-inflammatory drugs diclofenac sodium, indomethacin and phenylbutazone from urine prior to high-performance liquid chromatography was investigated. The drugs were recovered from urine buffered at pH 5.0 using C18 Bond-Elut cartridges as solid sorbent material and mixtures of methanol–aqueous buffer or acetonitrile–aqueous buffer as washing and elution solvents. The extracts were chromatographed on a reversed-phase ODS column using 10 mM acetate buffer (pH 4.0)–acetonitrile (58:42, v/v) as the mobile phase, and the effluent from the column was monitored at 210 nm with ultraviolet detection. Absolute recoveries of the anti-inflammatory drugs within the range 0.02–1.0 μg/ml were about 85% for diclofenac and indomethacin, and 50% for phenylbutazone without any interference from endogenous compounds of the urine. The within-day and between-day repeatabilities were in all cases less than 5% and 10%, respectively. Limits of detection were 0.007 μg/ml for diclofenac sodium and indomethacin and 0.035 μg/ml for phenylbutazone, whereas limits of quantitation were 0.02 μg/ml for diclofenac and indomethacin and 0.1 μg/ml for phenylbutazone.  相似文献   

12.
This article describes the development and validation of a simple solid phase extraction (SPE) and HPLC method for the extraction and the specific determination of prednisolone and hydrocortisone (cortisol) in both plasma and urine using one washing step with Oasis hydrophilic lipophilic balanced (HLB) cartridges (1 ml/30 mg, 30 microm). Recoveries of prednisolone and cortisol from plasma and urine exceeded 82%. The limit of quantification (LOQ) in plasma and urine was 9.9 and 6.7 ng/ml for cortisol, respectively, and 11.6 and 8.0 ng/ml for prednisolone, respectively. The intraday and interday precision (measured by CV%) for both prednisolone and cortisol in both plasma and urine was always less than 7%. The accuracy (measured by relative error %) for both prednisolone and cortisol in both plasma and urine was always less than 8%. The advantages of the developed method are the use of a one step washing SPE utilising HLB cartridges which do not suffer the drying out problems of conventional SPE cartridges and the time saving when compared with solvent extraction (SE), in addition to the simultaneous determination of prednisolone and cortisol in both plasma and urine.  相似文献   

13.
A novel chemiluminescence method for the determination of gentiopicroside is presented, which was based on the inhibitory effect of gentiopicroside on the chemiluminescence reaction between luminol and myoglobin in a flow‐injection system. The decrement of chemiluminescence intensity was linear with the logarithm of gentiopicroside concentration over the range from 10.0 pg mL?1 to 500.0 ng mL?1 (r2 = 0.9992), with a detection limit of 3.0 pg mL?1 (3σ). At a flow rate of 2.0 mL min?1, a complete analytical process could be performed within 0.5 min, including sampling and washing, with a relative standard deviation of less than 3.0% (n = 5). The proposed procedure was applied successfully in the determination of gentiopicroside in pharmaceutical preparations, human urine and serum without any pretreatment procedure. The possible mechanism of the reaction was also discussed. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

14.
Serum and urine chromium concentrations in elderly diabetics   总被引:5,自引:0,他引:5  
The serum and urine chromium concentrations of 57 diabetics and 55 normal fasting subjects were determined by atomic absorption spectrometry (AAS). Our results indicate that the chromium concentration ranges of serum and urine for diabetics are 0.22–0.36 and 4.54–5.90 μg/L, respectively, significantly lower than 0.66–0.84 7.80–9.68 μg/L for the normal (P<0.001), which implies that the elderly diabetics probably lack chromium. Further, it was found that the urine chromium level of the female diabetics was substantially higher than that of the male in the same age group (P<0.01), whereas the serum chromium level was almost the same. However, the urine chromium concentration increases with aging, no matter who the diabetics or the controls are. The serum chromium concentrations of the 24 cases patients with 2-h oral glucose tolerance test (OGTT) were significantly lower than that of those with empty stomach, whereas the urine chromium exhibits a contrary tendency. Our data indicate that the chromium lost and excreted from human body increases with aging and is related to the diabetics. Thus, it is recommended to supplement a certain amount of chromium to the elderly diabetics according to their nutritional level.  相似文献   

15.
The rice BAC-DNA was used as probes and fluorescence in situ hybridization (FISH) was applied to the interphase and metaphase mitotic chromosomes of maize. To optimize the BAC-FISH technique, we respectively assayed the effect of several factors, including maize or rice genomic C o t DNA used as blocking reagent of DNA, washing temperatures and FAD concentration in the washing buffer and in the hybrid solution. The results show that C o t DNA of maize genome blocked the repetitive sequence of the rice BAC-DNA when the C o t value was below 50. Meanwhile, it was necessary to adjust the C o t value according to the different probes and their ratios. Decreasing the concentration of FAD in the hybridization mixtures, adjusting the washing rate after hybridization, and most especially, blocking the ricespecific repetitive sequences of BAC-DNA could improve the positive signals of BAC-FISH. __________ Translated from Chinese Journal of Biochemistry and Molecular Biology, 2007, 23(1): 80–84 [译自: 中国生物化学与分子生物学学报]  相似文献   

16.
在变性条件下,应用Sephacryl-100凝胶过滤和Source-30Q阴离子交换两步分离,实现了分离纯化性质不稳定、易于降解的视黄醇结合蛋白(RBP)之目的。最后经过分步缓慢复性,获得具有生物活性的RBP,为其单克隆抗体制备及最终应用于临床营养评价和相关疾病的诊断创造了条件。  相似文献   

17.
The mechanism underlying olfactory predator identification may be relatively experience‐independent, or it may rely on specific experience with predators. A mechanism by which prey might identify novel predators relies on the inevitable creation of sulfurous metabolites that are then excreted in the urine of carnivorous mammals. We tested whether free‐living, yellow‐bellied marmots (Marmota flaviventris) and mid‐sized herbivores that fall prey to a variety of carnivorous mammals could discriminate herbivore (elk—Cervus elephas) urine from predator (red fox—Vulpes vulpes, coyote—Canis latrans, mountain lion—Felis concolor, wolf—Canis lupus) urine, a novel herbivore (moose—Alces alces), and a distilled water control. We further asked how specific this assessment was by testing whether marmots responded differently to predators representing different levels of risk and to familiar vs. unfamiliar predators. We found that marmots responded more to urine from coyotes (a familiar predator on adults), mountain lions (a potentially unfamiliar predator that could kill adults) and wolves (a locally extinct predator that could kill adults) than to elk urine (a non‐predator). Red fox (a predator that poses a risk only to recently emerged marmot pups) urine elicited a less substantial (but not significantly so) response than coyote urine. Marmots can identify predators, even novel ones, using olfactory cues, suggesting that experience with a specific predator is not required to identify potential threats.  相似文献   

18.
Synthetic and natural attractants in traps are used in many parts of the world to attract female tabanids. Certain attractants in different geographic regions may be ineffective or effective under different environmental conditions for horseflies. One‐octen‐3‐ol, as a compound present in bovine emanations, has a behavioural effect on many horsefly species and together with other phenolic compounds makes very effective attractant for this group of insects. As the attractiveness of the mixture of three chemicals (1‐octen‐3‐ol, acetone and ammonia solution in the proportions 5 : 3 : 2), aged donkey urine, lactic acid and fresh human urine is not yet known, it was studied in Eastern Croatia. The combination of those three chemicals and efficiency of natural attractants offers promising results. Tabanus was the most represented genus with 83% of the total collected tabanids. The chi‐squared analyses of the trapping data for canopy traps revealed that each of the attractants (mixture of three chemicals, aged donkey urine, lactic acid and fresh human urine) significantly increased the number of collected horseflies in comparison to those collected in unbaited canopy traps. Some species differences in relative response to different attractants were noted. Significantly, more specimens of Haematopota pluvialis were collected from canopy traps baited with the mixture of three chemicals when compared with traps baited with other attractants. Canopy traps baited with aged donkey urine collected significantly more Atylotus loewianus females than did traps baited with the mixture. The Ftest analysis of the trapping data for the genus Tabanus showed that there is significant difference between average number of collected specimens between mixture of three chemicals and other used attractants (lactic acid and human urine) except aged donkey urine. Finally, traps baited with the mixture of three chemicals (1‐octen‐3‐ol, acetone and ammonia solution) collected 14.5 times more tabanids than unbaited traps, whereas aged donkey urine, lactic acid, and fresh human urine‐baited traps collected 12, 3.9 and 2.5 times as many tabanids, respectively, than did unbaited traps. The mixture of three chemicals (1‐octen‐3‐ol, acetone and ammonia solution) and aged donkey urine appear to be very effective attractants for tabanids.  相似文献   

19.
The efficacy of lipase from Aspergillus niger MTCC 2594 as an additive in laundry detergent formulations was assessed using response surface methodology (RSM). A five-level four-factorial central composite design was chosen to explain the washing protocol with four critical factors, viz. detergent concentration, lipase concentration, buffer pH and washing temperature. The model suggested that all the factors chosen had a significant impact on oil removal and the optimal conditions for the removal of olive oil from cotton fabric were 1.0% detergent, 75 U of lipase, buffer pH of 9.5 and washing temperature of 25°C. Under optimal conditions, the removal of olive oil from cotton fabric was 33 and 17.1% at 25 and 49°C, respectively, in the presence of lipase over treatment with detergent alone. Hence, lipase from A. niger could be effectively used as an additive in detergent formulation for the removal of triglyceride soil both in cold and warm wash conditions.  相似文献   

20.
High concentrations of Syncephalastrum racemosum spores germinated less readily than low concentrations. Extensive washing of spores alleviated this inhibition of germination. Analysis of the spore washings revealed the main constituent to be nonanoic acid. Exogenously added nonanoic acid was found to mimic the self-inhibition, in that it delayed the time of germ tube emergence and increased the lag before spore swelling commenced.  相似文献   

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