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111.
S. Gepi-Attee I. A. Silver R. C. L. Feneley J. White 《Journal of materials science. Materials in medicine》1996,7(12):745-747
Tests of biocompatibility are obligatory in the development of implants. Use of a polycarbonate transparent rabbit ear is a practical and relatively economical way of observing and documenting progressive interaction between potential prosthetic materials and granulation tissue. Fabrication of the chambers is technically straightforward and the surgical procedure involved in their insertion is simple and minimally invasive. 相似文献
112.
Charles A. White John F. Kennedy Anna Lombard Valeria Rossetti 《Polymer International》1985,17(4):327-329
The oligosaccharide component compositions of a series of non-reducing oligosaccharides extracted from the roots of Arnica montana L. has been determined by gel permeation chromatography (g.p.c.). The range of oligosaccharides present was found to extend beyond the octasaccharide previously reported. with 16% to 19% of the oligosaccharides having a degree of polymerisation of between 11 and 19 and almost 3% having a degree of polymerisation greater than 20. The chromatographic behaviour of this series of oligosaccharides is compared with that observed for series of D-gluco-oligosaccharides. 相似文献
113.
Although filial therapy has traditionally been viewed as suitable for children of diverse cultures, there is limited research to support this perspective. This qualitative case study examined the perceived effectiveness of filial therapy for a Jamaican mother and the perceived effect on the mother-child relationship. Findings indicate that some aspects of filial therapy are congruent with the parenting practices and values of this Jamaican mother. The mother reported an increase in empathy, a heightened awareness of her child's needs, and a stronger relationship with her child. She expressed some difficulty with limit setting and tracking skills taught as part of the model. Future research directions include further examination of the compatibility of filial therapy with other Jamaican parents and the effectiveness of group filial therapy with Jamaican parents or other parents of Caribbean descent. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
114.
Multiresidue determination of pesticides in apples and pears by gas chromatography-mass spectrometry
E Lacassie MF Dreyfuss JL Daguet M Vignaud P Marquet G Lachatre 《Canadian Metallurgical Quarterly》1998,805(1-2):319-326
This paper describes a rapid, specific and sensitive multiresidue method for the routine analysis of several classes of pesticides used for the treatment of apples and pears, involving a rapid extraction procedure at pH 4.5 with a mixture of acetone-dichloromethane-hexane (50:20:30, v/v/v) and gas chromatography coupled to mass-selective detection, in order to achieve quantitative analysis down to their respective maximum residue limit. Extraction recoveries were between 55 and 98%. Limits of detection and limits of quantitation ranged respectively, from 0.01 to 0.05 mg/kg and from 0.02 to 0.1 mg/kg. Intra-assay relative standard deviation was less than 19% for all compounds. An excellent linearity was observed from these LOQs up to 500 mg/kg. Intermediate (inter-assay) precision and accuracy were satisfactory. The method has been applied to many fruit samples intended for commercialisation. 相似文献
115.
DD De La Tour D Raccah MF Jannot T Coste C Rougerie P Vague 《Canadian Metallurgical Quarterly》1998,41(9):1080-1084
The purpose of this study is to clarify the volume effect of epidural saline injection 20 min after spinal anesthesia. Thirty patients undergoing combined spinal and epidural anesthesia for orthopedic surgery were randomly divided into two groups: a control group (n = 15) and a saline group (n = 15). In the control group, 2% lidocaine 3 ml with 0.4% tetracaine was injected into the subarachnoid space from L 4-5 interspace using Durasafe (Becton Dickinson, USA) and saline was not injected into the epidural space. In the saline group, saline 10 ml was injected through an epidural catheter 20 min after spinal anesthesia. The levels of analgesia 20 min after spinal anesthesia were not significantly different between the groups. However, the levels of analgesia 3, 5, 10, 40 and 100 min after epidural saline injection in the saline group were significantly higher than those in the control group (P < 0.05). The highest analgesic level was obtained 10 min after epidural saline injection and reached to T 4.3 +/- 1.1. In conclusion, epidural saline injection increases the analgesic level 20 min after spinal anesthesia because of the volume effect. 相似文献
116.
The purpose of this study was to investigate platelet effects on postischemic heart function in conjunction with adenosine effects on intracoronary platelet adhesion. Homologous platelets were infused into the coronaries of isolated guinea pig hearts, either during low-flow ischemia or during reperfusion, and external heart work (EHW) and intracoronary platelet adhesion were determined. In most experiments, thrombin was added to the perfusate. The influence of endogenous adenosine was studied by use of the uptake blocker dipyridamole and the unspecific adenosine-receptor blocker theophylline, the A1-receptor blocker 8-cyclopentyl-1,3-dipropylxanthine (DPCPX), and the A2-receptor blocker 3,7-dimethyl-1-propargylxanthine (DMPX). The importance of nitric oxide and prostaglandin I2 (PGI2) was tested by using nitro-L-arginine (NOLAG) and indomethacin, respectively. When platelets were applied with thrombin during low-flow ischemia, EHW recovered to only 63 +/- 4% of the preischemic value, as compared with 89 +/- 3% without platelets (p < 0.05). Despite thrombin, platelets incurred no significant functional loss when applied in the first minute of reperfusion (but again in the fifth minute); however, when theophylline was also present, recovery of EHW amounted to only 42 +/- 12%. Intracoronary adhesion of platelets was negligible without thrombin, and highest during low-flow ischemia with thrombin (35 +/- 3% of the applied number). No adhesion occurred during the first minute of reperfusion, whereas in the fifth minute, adhesion was again 20.8 +/- 4%. Dipyridamole increased adenosine release and attenuated adhesion at this time. Theophylline increased adhesion in the first minute of reperfusion (33 +/- 6.4%), whereas NOLAG and indomethacin proved to be ineffective. DPCPX and DMPX each increased platelet retention during the first minute of reperfusion, their effects being additive. Intracoronary adhesion of platelets induced by thrombin in isolated hearts can reduce postischemic recovery of heart function. During reperfusion, but not during low-flow, endogenous adenosine can prevent platelet adhesion and loss of myocardial function, an action mediated both by A1- and A2-receptor-dependent mechanisms. 相似文献
117.
M Schmoeckel FN Bhatti A Zaidi E Cozzi PD Waterworth MJ Tolan G Pino-Chavez M Goddard RG Warner GA Langford JJ Dunning J Wallwork DJ White 《Canadian Metallurgical Quarterly》1998,65(12):1570-1577
BACKGROUND: Previous studies demonstrated that hearts from transgenic pigs expressing human decay-accelerating factor (hDAF) were not hyperacutely rejected when transplanted heterotopically into the abdomen of cynomolgus monkeys. This study examines orthotopic transplantation of hDAF transgenic pig hearts into baboon recipients. METHODS: Orthotopic xenogeneic heart transplantation was performed using piglets, transgenic for hDAF, as donors. Ten baboons were used as recipients and were immunosuppressed with a combination of cyclophosphamide, cyclosporine, and steroids. RESULTS: Five grafts failed within 18 hr without any histological signs of hyperacute rejection. Pulmonary artery thrombosis induced by a size mismatch was observed in two of these animals. The other three recipients died because of failure to produce even a low cardiac output and/or dysrhythmia. The remaining five animals survived between four and nine days. One animal died of bronchopneumonia on day 4. Three xenografts stopped beating on day 5 due to acute vascular rejection. The longest survivor was killed on day 9 with a beating, histologically normal xenograft, because of pancytopenia. CONCLUSIONS: The results reported here demonstrate that hDAF transgenic pig hearts are not hyperacutely rejected when transplanted into baboon recipients. Orthotopically transplanted transgenic pig hearts are capable of maintaining cardiac output in baboons. An optimum immunosuppressive regimen is the subject of ongoing research. 相似文献
118.
119.
The mitochondrial inner membrane anion channel (IMAC) is a transport pathway which is believed to be involved in mitochondrial volume homeostasis. The protein, however, has not been identified. In this paper, we examine the relationship between IMAC and the adenine nucleotide translocator. Many inhibitors of the adenine nucleotide translocase are shown to block IMAC, including Cibacron blue 3GA, bromcresol green, alizarin red S, agaric acid, palmitoyl-CoA, and the fluorescein derivatives erythrosin B, erythrosin isothiocyanate, rose bengal, and eosin Y. The following evidence suggests that Cibacron blue, agaric acid, and palmitoyl-CoA inhibit by binding to a common site. 1) They all only partially block the transport of small anions such as Cl-, NO3-, and HCO3-, but completely block the transport of larger anions such as malonate. 2) They decrease the IC50 values of each other in a manner consistent with competitive binding. 3) N-Ethylmaleimide decreases their IC50 values by a similar extent. 4) Inhibition by all shows no dependence on matrix pH and only a small dependence on medium pH. It is suggested that these agents may selectively bind to an open state of IMAC and inhibit by decreasing its conductance. The physiological nucleotides CoA, NAD+, NADH, NADP+, NADH, and ATP do not inhibit; in fact, IMAC is shown to transport ATP. Despite these similarities between IMAC and the adenine nucleotide translocase, IMAC appears to be a separate entity, since some of the IC50 values differ by up to 8-fold, and carboxyatracyloside, the most selective inhibitor of the adenine nucleotide translocase, has no effect on IMAC. In addition, IMAC is also able to transport AMP, while the adenine nucleotide translocase does not. 相似文献
120.
Bovine rotavirus strain B223 is the North American prototype for group A P8[11] serotype/genotype rotaviruses. Rotaviruses with this serotype/genotype are a prevalent cause of neonatal calf diarrhea and have also been isolated from asymptomatic human infants. On the basis of deduced amino acid sequence of the outer capsid viral protein 4 (VP4), strain B223 lacks a cysteine at position 318 that is conserved among all other rotavirus strains. It has been speculated that this may result in the loss of disulfide bond and a change in the structure of the VP4 that may affect the infectivity and antigenicity of the virus. This paper describes partial sequences of the VP4 gene (nucleotides 613 to 1016 coding for amino acid positions 202 to 335) of 16 bovine rotavirus field isolates with P8[11] that were obtained from calves in Nebraska and Indiana. All the isolates lack a cystein at position 203 and had a conserved valine residue at position 318, thus indicating that the prototype strain B223 is representative of group A rotaviruses with P8[11] serotype/genotype. 相似文献