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71.
Preliminary experiments indicated that solutions of aspirin (ASA) in buffered saline, pH 7.35, did not significantly change nasal airways resistance (NAR) when 0.1 ml of solution containing 22.5 mg (or less) per deciliter was sprayed into each nostril. Subsequently it was shown that this quantity of ASA administered intranasally did not significantly change NAR responses 15 min later to intranasal administration of increasing concentrations of histamine, methacholine, or an irritant (NH3 gas). However, the same atopic subjects demonstrated significantly decreased responses to intranasal challenge with short ragweed extract (SRW) after intranasal ASA. In addition, prior oral administration of ASA, Na salicylate, and indomethacin significantly inhibited nasal challenge responses to SRW in sensitive subjects under controlled conditions.  相似文献   
72.
Five stable hybridoma lines were prepared using the myeloma cell line P3-X63-Ag.653 and spleen cells of mice hyperimmunized by pig transferrin. All hybridomas grew well in mouse peritoneal cavity and produced antibodies of the IgG1 subclass. Antibody preparations obtained from ascitic fluids tested for their capacity of antigen precipitation. No precipitation was obtained with single antibodies and with pairs of antibodies. Three out of 10 possible triads gave clear and sharp precipitation zones and rings in immunodiffusion tests performed in agar gel. All 5 antibodies were shown by quantitative enzyme-immunoassay to be specific for pig transferrin: no cross-reaction was obtained with mouse, human, horse and sheep transferrins.  相似文献   
73.
Immunocytochemical studies, using a polyclonal antibody directed against tyrosine hydroxylase, identified catecholaminergic axons in prefrontal cortex of young and aged nonhuman primates. Aged monkeys, who showed cortical senile plaques in silver stains, had swollen tyrosine hydroxylase-immunoreactive axons in neocortex. Some of these abnormal processes were associated with deposits of amyloid (visualized by thioflavin-T fluorescence) and were similar in appearance to neurites demonstrated by silver impregnation methods. This study provides evidence for structural abnormalities in catecholaminergic axons/nerve terminals in the neocortices of aged primates.  相似文献   
74.
702例正常成人红细胞变形性与性别、年龄的相关性   总被引:1,自引:1,他引:1  
采用激光衍射法对702例正常成人的红细胞变形指数DI值测定,并将测得的各个数据随年龄增长配对分不同年龄(范围)组作相关性研究。结果发现正常成人红细胞变形性随增龄呈抛物线状的改变。性别年龄与红细胞变形性关系有如下特征:(1)18~29岁男女组的DI值随增龄呈上升状态,达到正常成人的高峰,与增龄呈显著正相关,相关有显著意义,P<0.05。(2)18~44岁男女组随增龄DI值开始呈缓慢下降趋势,相关性由18~29岁的正相关逐渐过渡到负相关,相关无显著性意义,P>0.05。(3)18~49岁开始直至79岁男女各组随增龄红细胞变形性明显下降,与增龄呈显著负相关,相关有非常显著意义,P<0.001。男女性的DI值,54岁以前男女各组间比较,经t检验,无显著性差异,P>0.05;18~59、18~64、18~74和18~79岁男女组间比较,有显著性差异,P<0.05。结果提示:正常成人在青年、壮年和老年前期、老年期的红细胞变形性有其不同变化特点,性别年龄与红细胞变形性相关有显著意义。  相似文献   
75.
A complex of rabbit IgG antibody with horseradish peroxidase covalently linked to Sepharose 4B was used as an insoluble immune complex for studying the binding of complement factor C1q protein A from Staphylococcus aureus, and its IgG-binding fragments AB and B, to rabbit IgG. It was shown that protein A (mol. wt approx. 42,000) and fragments AB and B (mol. wts approx. 14,000 and 7000, respectively) inhibited the binding of C1q to insoluble immune complex at 4 degrees C. However, at 37 degrees C fragment B did not inhibit this binding. On the other hand, C1q, when bound to an insoluble immune complex, almost completely blocked the binding of protein A and fragment B at both temps. The higher affinity of C1q for its CH2-binding site than of fragment B for its CH2-binding site may explain the displacement of the latter from the CH2 domain. The mutual inhibition of the binding of C1q and protein A (and its smaller fragments) indicates that the binding sites for C1q and protein A are closely located in the CH2 domain.  相似文献   
76.
Histological appearances of the long saphenous vein   总被引:1,自引:0,他引:1  
The long saphenous vein is frequently used as a graft in both coronary artery and femoro-distal bypass surgery. The histological changes which are seen after implantation into the arterial system have been well documented in the past, but little attention has been focused on the histological appearances of the donor long saphenous vein prior to grafting. In this study, samples of the long saphenous vein in excess of that required for bypass have been examined. In none of the veins did the histological appearances conform to the described normal. All showed evidence of intimal fibrosis which contained elastic tissue and enmeshed smooth muscle cells. The longitudinal and circular muscle layers showed evidence of muscle cell hypertrophy with increase in intervening connective tissue. Elsewhere, similar histological changes have been attributed to 'arterialization'. This study shows that many of the changes are present prior to grafting and may be important in graft failure.  相似文献   
77.
The ingestive responses of rats given celiac vagotomy (C), combined celiac and hepatic vagotomy (CH), or low total vagotomy (removal of all tissue from around the esophagus, stomach and duodenum; LT) were compared with sham operated controls (S) in a series of regulatory challenges. The vagotomized groups responded normally to 2-deoxy-D-glucose (2DG; 125, 250, 500 mg/kg, IP), insulin (4, 8, 12 U/kg, IP), and polyethylene glycol (10 ml/kg: 30% w/v, SC), but displayed attenuated responses to epinephrine (40, 80, 120 micrograms/kg, IP) and hypertonic saline (10 ml/kg: 0.25, 0.5, 1.0 M, IP). These results can be interpreted as evidence that the celiac vagus carries a major component of hepatic afferent innervation. Additionally, when considered with other findings they suggest that whereas the anorectic activity of epinephrine is mostly confined to the liver, 2DG hyperphagia involves stimulation of a wider population of peripheral metabolic receptors.  相似文献   
78.
Antisera produced in rabbits against pure fractions of cholinergic vesicles from Narcine brasiliensis were used to study cholinergic organelles in rat motor neurons. The indirect immunofluorescence method was used on perfusion-fixed material. The rats were surgically sympathectomized to remove sympathetic adrenergic and cholinergic nerves from the sciatic nerve. In the intact animal immunoreactive material, likely to represent cholinergic vesicles, was observed in motor endplates, identified by labelling with rhodamine-conjugated α-bungarotoxin or with subsequent acetylcholinesterase staining. The motor perikarya contained very little immunoreactive material. Non-terminal axons were virtually devoid of immunofluorescence in the intact animal. After crushing the sciatic nerve, immunoreactive material (likely to represent axonal cholinergic organelles) accumulated rapidly on both sides of the crush, indicating a rapid bidirectional transport. The transport was sensitive to local application of mitotic inhibitors.The axons which accumulated immunoreactive organelles were motor axons, as demonstrated by various procedures: (1) Cutting of ventral roots prevented accumulation of immunoreactive material in the nerve. (2) Deafferentation did not notably influence accumulations of immunoreactive material. (3) Ligated axons with immunoreactive material were acetylcholinesterase positive when identification was made on the same section; the intra-axonal distribution of immunoreactive material and acetylcholinesterase was not identical, however, and the Narcine antisera did not cross-react with bovine acetylcholinesterase in a solid phase immunoassay. (4) Most axons in ventral roots, but not in dorsal roots, accumulated strongly fluorescent immunoreactive material, while axons in dorsal roots contained weakly fluorescent material. On the other hand, substance P-like immune reactivity was present in many dorsal root axons, but only very rarely in ventral roots.It is suggested that the antisera against Narcine cholinergic vesicles can be used as a marker for cholinergic organelles in the motor neuron, and may be an important tool for studying the axonal cholinergic vesicles. It cannot, however, be used to identify cholinergic structures in unknown locations because it recognizes common antigenic determinants in transmitter organelles of other nerves e.g. adrenergic nerves. The axonal cholinergic organelles may carry important molecules, other than acetylcholine to the nerve endings.  相似文献   
79.
Using short term CTL lines derived from HLA A2/Kb transgenic mice and IFN-gamma release assays we demonstrate that the NS4.1769 epitope, is generated from natural processing of the NS4 antigen, and presented in the context of the A2/Kb molecules. Interestingly, T cell recognition of the naturally processed form of the NS4.1769 epitope was associated with significant IFN-gamma release, but no direct cytolytic activity. Epitopes of this phenotype might be of interest, in terms of therapy of chronic HCV infection by associating the benefit of localized lymphokine release with low or absent direct cytopathicity.  相似文献   
80.
Various techniques are used to collect specimens from the nasal mucosa for morphologic and biochemical analysis. The purpose of this study was to devise a method that overcomes some of the disadvantages (e.g., invasive procedure, samples not suitable for cytologic and biochemical analysis, lack of standardization, and poor reproducibility) of these techniques. The new method requires subjects, with neck extended, to inhale an ultrasonic nebulization of a hypertonic (3% NaCl) solution (UNHS) for 5 min. They then blow their nose into a Petri dish, one nostril at a time with the other one blocked. The secretions are dispersed with 0.1% dithiothreitol in phosphate buffer solution for 20 min. Total cell count (TCC) is evaluated, and the cellular suspension is divided into two aliquots: one is centrifuged and the supernatants are collected for eosinophil cationic protein (ECP) measurements; the other is cytocentrifuged and the slides, stained with Diff-Quik, are used for differential cell count. The results obtained with the UNHS and nasal lavage (NL) methods were compared. Eleven nonatopic healthy subjects and 19 allergic rhinitic patients were studied. Total cell count (×105) was significantly higher with UNHS than with NL (13.0±12.3 vs 1.911.6; P<0.0]) The differential cell count was similar with the two procedures. ECP levels (μg/l) were higher with UNHS than with NL (39.1+38.2 V.S 16.7±41.2; P<0.01). For evaluation of reproducibility, four healthy and six rhinitic subjects underwent UNHS on two occasions within 5 days, and the results of two samples (sample 1 vs sample 2) were analyzed. Reproducibility was good as to TCC, differential cell count, and ECP  相似文献   
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