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1.
The Third International Workshop on Lymphocyte Alloantigens of the Horse was held on 25-27 April 1984 in Kennett Square, Pennsylvania. Twelve laboratories from five countries participated. The principal purpose of this Workshop was to determine the phenotypic and gene frequencies of the 10 equine lymphocyte antigens (ELA) and a non-ELA lymphocyte antigen, ELY-2.1, in several breeds of horse. A total of 86 alloantisera characterized in previous workshops were tested against lymphocytes from 1179 horses. In addition, several experimental antisera were also tested against the same panel of lymphocytes. As a result of analysis of these data, the Workshop recognized two new equine lymphocyte alloantigens: W11 of the ELA system, and ELY-1.1, an antigen not linked to the ELA system.  相似文献   

2.
Summary. The Third International Workshop on Lymphocyte Alloantigens of the Horse was held on 25–27 April 1984 in Kennett Square, Pennsylvania. Twelve laboratories from five countries participated. The principal purpose of this Workshop was to determine the phenotypic and gene frequencies of the 10 equine lymphocyte antigens (ELA) and a non-ELA lymphocyte antigen, ELY-2.1, in several breeds of horse. A total of 86 alloantisera characterized in previous workshops were tested against lymphocytes from 1179 horses. In addition, several experimental antisera were also tested against the same panel of lymphocytes. As a result of analysis of these data, the Workshop recognized two new equine lymphocyte alloantigens: W11 of the ELA system, and ELY-1.1, an antigen not linked to the ELA system.  相似文献   

3.
The short-distance, PC-dedicated implanted telemetry system is described. Schematic drawings of the transmitter and Centronics port interface are given and the main problems of the controlling program are discussed. The interface can be easily converted to serve as an analog output and the method of adaptation is demonstrated. The whole system was tested in animal experiments with two different amplifiers and the examples of resulting direct ECG and both direct and integrated intestinal EMG recordings are included.  相似文献   

4.
Proto-fix (Alpha-Tec Systems, Inc., Vancouver, WA) is a new single vial, environmentally safe, parasitology (pathogenic and nonpathogenic protozoans and helminths) fixative and transport solution. It is used in conjunction with a new concentration/sedimentation reagent, CONSED, (Alpha-Tec Systems, Inc. Vancouver, WA) as a replacement to the formalin-ethyl acetate (FEA) concentration procedure using Lugol's iodine. The newly adopted procedure was tested against the FEA concentration samples using split proficiency testing samples supplied by the American Association of Bioanalysts (AAB). Routinely, patient samples collected, fixed, and transported in Proto-Fix were processed and tested at Diagnostic Labs, Inc. (DLI), Phoenix, AZ. Detected parasites were documented using a video camera-printer system attached to the optical equipment. The quality of the fixative and stain were found to be superior to that of the FEA-Lugol's method and the yield of detected parasites was considerably higher. Eighty-five percent of 39 unknown parasite species tested were correctly detected using the Proto-fix-CONSED system compared to 46% using the FEA-Lugol's method. Of all the other methods and stains used at DLI, the trichrome stain (a popular modification of Gomori's trichrome stain for tissue sections) was found to be least reliable.  相似文献   

5.
The mutagenicities of naturally occurring xanthones were tested in Salmonella typhimurium TA100, TA98, TA97, and TA2637 by the preincubation method. Xanthydrol, gentisein, gentisin, isogentisin, 1-hydroxy-3,7-dimethoxyxanthone, 1,3,7,-trimethoxyxanthone, desmethylbellidifolin, bellidifolin and dimethylbellidifolin were mutagenic, but unsubstituted xanthone was not mutagenic to TA100, TA98, TA97 and TA2637 with or without a metabolic activation system. The β-O-glucosides, norswertianolin and swertianolin, were only mutagenic when a metabolic activation system containing β-glucosidase was used, and the C-glucoside mangiferin was not mutagenic even with this system.  相似文献   

6.
Dansyl derivatives of epsilon-N-mono-, epsilon-N-di-, and epsilon-N-trimethyllysine were resolved from other amino acids in proteins by the use of high-performance liquid chromatography. The system was tested with amino acid standard combinations as well as with acid-hydrolyzed proteins known to contain methylated residues. In all cases the methylated lysines were well resolved.  相似文献   

7.
通过对重组人尿激酶原(rhRhpro-UK)不同剂量(8万IU/kg和16万IU/kg)对家兔纤溶功能的影响并与尿激酶(UK)(8万IU/kg)比较实验显示,rhpro-UK和UK都能明显缩短兔优球蛋白溶解时间,rhpro-UK对纤溶参数影响比UK小.rhpro-UK对体外血栓的溶解作用随剂量增加而增加,与同剂量UK比较有显著差别.rhpro-UK和UK对猪冠脉血栓都有明显的溶栓作用,对猪的纤溶指标纤维蛋白原(FG)、纤溶酶原(PLG)和α2抗纤溶酶(α2-AP)无明显影响.rhpro-UK对出血时间、凝血时间、单位时间内出血量均明显低于UK.表明rhpro-UK的副作用明显低于UK.rhpro-UK对小鼠、大鼠、犬和豚鼠回肠的一般药理学实验表明,rhpro-UK对受试动物的一般行为、状态及中枢神经系统、心血管系统、呼吸系统、消化系统等均无明显影响.仅发现犬实验中手术创面有渗血现象,对全身血液有类似肝素化状态.rhpro-UK的毒理实验表明,rhpro-UK的半数致死量为97.5mg/kg;Beagle犬接受2,8,28mg/kgrhpro-UK后,除8mg和28mg组有一过性牙龈充血,凝血时间明显延长,Tchol,TP和Alb含量有升高趋势外,未观察到明显毒性反应,病理学检查也未观察到药物造成直接的脏器损伤,2mg/kg组未观察到任何毒副反应.特殊毒性实验表明,rhpro-UK没有致突变和致畸作用.  相似文献   

8.
Dansyl derivatives of epsilon-N-mono-, epsilon-N-di-, and epsilon-N-trimethyllysine were resolved from other amino acids in proteins by the use of high-performance liquid chromatography. The system was tested with amino acid standard combinations as well as with acid-hydrolyzed proteins known to contain methylated residues. In all cases the methylated lysines were well resolved.  相似文献   

9.
Predation risk is allegedly reduced in Batesian and Müllerian mimics, because their coloration resembles the conspicuous coloration of unpalatable prey. The efficacy of mimicry is thought to be affected by variation in the unpalatability of prey, the conspicuousness of the signals, and the visual system of predators that see them. Many frog species exhibit small colorful patches contrasting against an otherwise dark body. By measuring toxicity and color reflectance in a geographically variable frog species and the syntopic toxic species, we tested whether unpalatability was correlated with between‐species color resemblance and whether resemblance was highest for the most conspicuous components of coloration pattern. Heterospecific resemblance in colorful patches was highest between species at the same locality, but unrelated to concomitant variation in toxicity. Surprisingly, resemblance was lower for the conspicuous femoral patches compared to the inconspicuous dorsum. By building visual models, we further tested whether resemblance was affected by the visual system of model predators. As predicted, mimic‐model resemblance was higher under the visual system of simulated predators compared to no visual system at all. Our results indicate that femoral patches are aposematic signals and support a role of mimicry in driving phenotypic divergence or mimetic radiation between localities.  相似文献   

10.
Pemphigus is an autoimmune blistering disease of the skin and mucous membranes. It is caused by autoantibodies directed against desmosomes, which are the principal adhesion structures between epidermal keratinocytes. Binding of autoantibodies leads to the destruction of desmosomes resulting in the loss of cell-cell adhesion (acantholysis) and epidermal blisters. The plasminogen activator system has been implicated as a proteolytic effector in pemphigus. We have tested inhibitors of the plasminogen activator system with regard to their potential to prevent pemphigus-induced cutaneous pathology. In a human split skin culture system, IgG preparations of sera from pemphigus vulgaris patients caused histopathologic changes (acantholysis) similar to those observed in the original pemphigus disease. All inhibitors that were tested (active site inhibitors directed against uPA, tPA, and/or plasmin; antibodies neutralizing the enzymatic activity of uPA or tPA; substances interfering with the binding of uPA to its specific cell surface receptor uPAR) failed to prevent pemphigus vulgaris IgG-mediated acantholysis. Plasminogen-mediated acantholysis, however, was effectively antagonized by the synthetic active site serine protease inhibitor WX-UK1 or by p-aminomethylbenzoic acid. Our data argue against applying anti-plasminogen activator/anti-plasmin strategies in the management of pemphigus.  相似文献   

11.
The effect of the antihelminthic substance Praziquantel on the peptidergic nervous system in the adult gull-tapeworm Diphyllobothrium dendriticum was tested. As well as increasing muscle contraction the drug provoked a fall in the amount and size of the peptidergic nerve terminals in the subtegumental region. The number of small clear vesicles in the terminals also fell.  相似文献   

12.
13.
Assuming that the acquisition and retention of memories havecosts, properties of memories should fit the functional requirementsfor the system of memory. Based on a functional analysis ofwhat path integration is meant to do, we predicted that odometricmemories in desert ants should show (1) little improvement withrepeated training: performance should be as good after one trainingtrial as after six training trials, (2) decay of memory after24 h, and (3) performance based solely on the most recent outboundtrip, with no integration over multiple memories. Desert ants(Cataglyphis fortis) traveled in narrow straight plastic channelsto forage for cookie crumbs in a feeder at 6- or 12-m distance.Each ant was tested once by being taken from the feeder andreleased 2 m from the end of a 32-m channel to run home. Thedistance at which the ant first turned back (first turn) constitutedthe data. In acquisition, groups trained one or six times beforebeing tested had unsystematic scatter that did not differ significantly.In retention, ants tested after a 24-h delay showed larger unsystematicscatter than control animals tested after no delay. In integration,ants were trained five times at 6 or 12 m and then tested at12 or 6 m, respectively. No evidence of integration of multipleodometric memories was found. The results show that the propertiesof odometric memories are indeed tailored to what the memorysystem is used for.  相似文献   

14.
The lignin peroxidase enzyme system of the white-rot fungus, Phanerochaete chrysosporium was assayed for its capacity to degrade two recalcitrant aliphatic ether compounds, high-molecular-mass polyethylene glycol (PEG 20 000) and methyl tert-butyl ether. Ligninolytic cultures of Phanerochaete chrysosporium were spiked with each ether compound and incubated in reaction vessels. Separate incubations were conducted in which the ether compounds were present as sole carbon source. Other parameters, such as varying the methyl tert-butyl ether concentration and veratryl alcohol additions were tested. No significant degradation of either compound was observed under any of the conditions tested. Implications of these results are discussed with respect to the oxidative limitations of the lignin peroxidase enzyme system and structural features of substrate molecules that may be requisite for oxidation by this system.  相似文献   

15.
We examined the sensitivity of the ferret to emetic stimuli and the effect of radiation exposure near the time of emesis on local cerebral blood flow. Ferrets vomited following the administration of either apomorphine (approx 45% of the ferrets tested) or peptide YY (approx 36% of those tested). Exposure to radiation was a very potent emetic stimulus, but vomiting could be prevented by restraint of the hindquarters of the ferret. Local cerebral blood flow was measured using a quantitative autoradiographic technique and with the exception of several regions in the telencephalon and cerebellum, local cerebral blood flow in the ferret was similar to that in the rat. In animals with whole-body exposure to moderate levels of radiation (4 Gy of 137Cs), mean arterial blood pressure was similar to that in the control group. However, 15-25 min following irradiation there was a general reduction of local cerebral blood flow ranging from 7 to 33% of that in control animals. These cerebral blood flow changes likely correspond to a reduced activation of the central nervous system.  相似文献   

16.
Concerns have been raised about interference of wireless local area network (LAN) systems and telemetry systems with medical devices in hospitals. The authors have investigated the susceptibility of 65 electromedical devices to a wireless LAN system and a telemetry system in preselected areas of a hospital. Testing was based on the American National Standards Institute Standard C63.18. The wireless LAN system operated at 2.42 GHz with an output power of 100 mW. The telemetry system operated at 466 MHz with an output power of 4 mW. Of the 65 devices tested, only two hand-held Doppler units, a Mini Doppler Model D900 (Huntleigh Healthcare Ltd) and a Ultrasonic Doppler Model 811 (Parks Medical Electronics, Inc.), were affected by the LAN system. Placed within 10 cm of the LAN system in standby mode, both units emitted periodic high-pitched beating sounds, which could be misinterpreted as normal beating sounds from the patient. These changed to random static noise during data transmission by the LAN. Under normal conditions of use, a LAN system would never be placed this close to a medical device. The quality of data transmission from the LAN system changed from "good" to "acceptable" in the colonoscopy room. This deterioration in transmission quality could have been caused by the lead shielding in the room. Electrosurgical devices operating at 0.5 to 1 MHz did not affect the LAN system at distances up to 3 m. None of the devices was affected by the telemetry system. These findings suggest that wireless LAN systems and telemetry systems can be acceptable for use in hospitals. Nevertheless, other systems should be tested on potentially susceptible devices by the hospital before use.  相似文献   

17.
Soils previously treated with landfarming to reduce petroleum hydrocarbon concentrations are often left with a less biodegradable residual fraction that can present challenges for additional treatment. Four possible polishing technologies were tested on the bench scale for weathered hydrocarbons present in fine-grain soils obtained from a previously landfarmed area at an active oil refinery. The technologies included additional bioremediation (both biostimulation and bioaugmentation tested), soil washing, chemical oxidation, and low-temperature thermal desorption. Multiple parameters were tested separately for each technology to identify possible factors that were relevant across technologies. Extractable hydrocarbons comprised only approximately 35% of the organic carbon in the soils, and this component was considerably less affected by biological, surfactant, and oxidant treatment than organic materials that are not quantified by the TEH analysis. Treatment testing of thermal desorption indicated removal of large quantities of extractable hydrocarbons despite the presence of high organic matter. The additional demand to the system would likely result in considerably large timeframes (biological treatment), reagent quantities (soil washing and oxidation), or energy input (thermal desorption) for treatment of target hydrocarbons on a full scale.  相似文献   

18.
Chemical-regulated, site-specific DNA excision in transgenic plants   总被引:37,自引:0,他引:37  
We have developed a chemical-inducible, site-specific DNA excision system in transgenic Arabidopsis plants mediated by the Cre/loxP DNA recombination system. Expression of the Cre recombinase was tightly controlled by an estrogen receptor-based fusion transactivator XVE. Upon induction by beta-estradiol, sequences encoding the selectable marker, Cre, and XVE sandwiched by two loxP sites were excised from the Arabidopsis genome, leading to activation of the downstream GFP (green fluorescent protein) reporter gene. Genetic and molecular analyses indicated that the system is tightly controlled, showing high-efficiency inducible DNA excision in all 19 transgenic events tested with either single or multiple T-DNA insertions. The system provides a highly reliable method to generate marker-free transgenic plants after transformation through either organogenesis or somatic embryogenesis.  相似文献   

19.
Thyrotropin-releasing hormone (TRH) has generally been reported to increase locomotor activity in rats; however there are also some negative reports. In order to identify the possible causes for this discrepancy, the effects of intra-cerebroventricular injection of TRH, its metabolites 'acid TRH' (TRH-OH) and His-Pro-diketopiperazine (DKP), and two analogues 3-methyl-His-TRH and RX 77368 (3,3-dimethyl-Pro-TRH), were assessed using photocell activity cages. All compounds were tested in groups of eight rats in the afternoon (1300-1700 h), but in addition TRH and DKP were tested in two further groups of rats during the morning (0900-1230 h). TRH and DKP failed to induce a significant rise in activity during the morning test period, but TRH did have a significant effect when tested in the afternoon. Both TRH and TRH-OH caused dose dependent increases in locomotor activity, whereas DKP and the two analogues had no effect. This stimulation of activity was shown to be at least partly mediated by dopamine since locomotor enhancement was blocked in a second experiment using the dopamine antagonist alpha-Flupenthixol. The results are discussed in terms of actions on the mesolimbic dopamine system, and the importance of circadian variations within this system to the expression of peptide effects in general.  相似文献   

20.
Crayfish hemocytes displayed cytotoxic capacity towards all tested mammalian tumor and nontumor cell lines. The ratio required for the cytotoxic action of effector cells to target cells was at least 1:1. The lysis of the target cells required a minimum of 1 hr to become detected. After separation and isolation of the hemocyte populations of crayfish, the semigranular and granular cells retained their cytotoxic capacity. These cells contain the prophenoloxidase activating (proPO) system, a complement-like pathway, which in an activated form lyses semigranular cells in vitro, but failed to kill the tested target cells.  相似文献   

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