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101.
The effect of adrenergic and cholinergic drugs on short incubation “active” E rosette formation was studied in 19 patients with bronchial asthma and 17 healthy controls. Both groups had an equal absolute number of baseline “active” E rosettes, but the asthmatics demonstrated a higher percent baseline value. The beta adrenergic drug isoproterenol (10?3 M) inhibited the formation of “active” E rosettes in asthmatics by only 18.0% as compared to a 60.8% inhibition in the control group. Carbamylcholine (10?5 M) a cholinergic agonist, also showed a lower than normal response in asthmatics, 34.3% enhancement of “active” E rosetting compared to a 52.4% enhancement in the controls. The alpha adrenergic agent phenylephrine (10?5 M) exhibited equal enhancing effects in both groups, 34.2% in the asthmatics and 36.5% in the controls. Isoproterenol (10?3 M) had a minimal effect on inhibition of long incubation “total” E rosettes in both groups studied. The beta adrenergic abnormality conforms to the beta blockade theory of asthma of Szentivanyi. The cholinergic abnormality is unexplained in view of the hyperresponsiveness of patients with asthma to cholinergic agents in vivo. Patients with bronchial asthma probably have an autonomic dysfunction that may play a role in the pathogenesis of their disease. 相似文献
102.
J Blomfield J A Simson A M Martinez J R Martinez 《Experimental and molecular pathology》1983,38(2):170-182
Rat submandibular gland tissue pieces were stimulated in vitro for 30 min with a beta-adrenergic agent or a cyclic AMP analog to stimulate protein secretion, or with alpha-adrenergic or cholinergic agents or a Ca2+ ionophore to stimulate fluid secretion. Acinar cells were examined by transmission electron microscopy. In control tissue, acinar cells showed little evidence of secretory activity. The Golgi apparatus was sparse and was associated with a few small, immature secretory granules with fine fibrillar contents. Following secretory granule discharge stimulated by isoproterenol or dibutyryl cyclic AMP, acinar cells were constricted, and had extensive basolateral membrane folding and tightly packed rough endoplasmic reticulum. Golgi complexes were prominent and had multiple small granules with filamentous contents. After stimulation of fluid secretion by alpha-adrenergic agents (epinephrine, phenylephrine), or cholinergic agents (acetylcholine, carbachol, pilocarpine), or a Ca2+ ionophore (A23187), the Golgi apparatus had compact concave cisternae enclosing aggregates of tubulovesicles. Acinar cells were distended, basolateral membranes were expanded, and rough endoplasmic reticulum was dilated and vesiculated. 相似文献
103.
Charles R. Bursey Stephen R. Goldberg Fred Kraus 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2007,52(2):142-145
Falcaustra papuensis sp. nov. (Ascaridida, Kathlaniidae) from the large intestine of Sphenomorphus simus (Squamata, Sciencidae) is described and illustrated. Falcaustra papuensis represents the 4th Australo-Papuan species assigned to this genus and is distinguished from other Australo-Papuan species
by the distribution pattern of caudal papillae (6 precloacal, 6 adcloacal, 8 postcloacal, and 1 median), length of spicules
(561–714 μm) and presence of a pseudosucker. Sphenomorphus simus was found to harbor 2 additional species of nematodes, Meteterakis crombiei and Oswaldocruzia bakeri. Sphenomorphus simus represents a new host record for each of these nematode species. 相似文献
104.
Immunohistochemical studies were performed to address the expression of the high-molecular-weight component of the neurofilament triplet NF200 (a marker of neurons forming A fibers) and the binding of isolectin B4 (IB4) by neurons of the L4-5 spinal ganglia after ligation or section of the sciatic nerve in rats. A total of 15% of neurons in the ganglia of intact rats expressed NF200. By 90 days after nerve ligation, the proportion of NF200+ neurons decreased two-fold; administration to these rats of the nerve regeneration stimulator xymedone increased the number of NF200+ neurons by 50.7% compared with controls (ligation, no treatment). In intact rats, 23.6% of neurons bound IB4. The proportion decreased by 2.6% 30 days after nerve ligation and to undetectable levels by 90 days; xymedone increased the proportion of surviving IB(4)+ neurons more than eight-fold. IB(4)+ neurons were more likely to enter post-traumatic apoptosis. Ligation of the nerve was followed by survival of fewer NF200+ and IB(4)+ neurons than section of the nerve, which suggests that axon lengthening is a factor maintaining neuron survival. The pyrimidine derivative xymedone increased the survival of neurons of both subpopulations, especially IB(4)+ neurons. 相似文献
105.
Minnebaev MM Mukhutdinova FI Zakharova LG Mukhutdinov DA 《Bulletin of experimental biology and medicine》2002,133(6):597-599
The survival of neurons is a key condition for complete posttraumatic regeneration of the peripheral nerve. In experiments on rats we studied survival capacity of different neuronal subpopulations in LIV-LV dorsal root ganglia after ligation or transection and suturing of the sciatic nerve. Experiments with nerve ligation showed that IB4+ neurons are more sensitive to the injury than NF200+ neurons. By day 90 after ligation of the sciatic nerve IB4+ neurons were virtually not detected in the dorsal root ganglia. By day 90 after nerve transection the number of surviving NF200+ and IB4+ neurons decreased by 26.1 and 21.4%, respectively, in comparison with intact animals. Treatment with xymedon, a regeneration stimulator, led to a 48.5% increase in the number of surviving NF200+ neurons by day 30 after ligation of the nerve and a 50.7% increase by day 90. The number of surviving IB4+ neurons increased more than 8-fold by this term after ligation of the nerve and drug stimulation. Xymedon had a neuroprotective effect towards both neuron subpopulations, more intensely preventing apoptosis of IB4+ neurons. 相似文献
106.
R Patterson K E Harris P A Greenberger 《The Journal of allergy and clinical immunology》1980,65(4):269-273
Prostaglandin (PG) D2 and PGI2 were evaluated to determine their effect on pulmonary function parameters when aerosolized in anesthetized rhesus monkeys. PGD2 resulted in an increase in frequency (f) and pulmonary resistance (rl) and a decrease in peak expiratory flow rate (PEFR), tidal volume (VT), and dynamic compliance (Cdyn), with the major effect on RL. PGI2 primarily effected an increase in f and a decrease in PEFR and VT. PGI2 had a variable effect, generally a decrease, on RL. The metabolite of PGI2, 6-keto-PGF 1 alpha, had no effect on the rhesus airway. PGF 2 alpha responses were similar to PGD2 except that the PGF 2 alpha produced a less strikingly consistent increase in RL. When PGI2 and PGD2 were aerosolized simultaneously, they simulated previously described antigen responses. Further, PGI2 plus PGD2 produced an airway response at 1/10 the concentration of either agent alone. 相似文献
107.
The human {T:T act} AMLR was characterized in its relationship to the {T:Non-T} AMLR and its validity as a nonxenogeneic antigen induced response was extended. Human T cell lines, established from responding T cells in an autologous mixed lymphocyte reaction (MLR), were maintained in medium containing human serum and interleukin-2 (IL-2). These cells stimulated 3H-thymidine incorporation by autologous T cells and by autologous unfractionated blood mononuclear cells. Freshly activated T cells isolated from an autologous MLR stimulated autologous T cells to a lesser extent could be enhanced by adding IL-2. Twenty-five to 50% of T cells stimulated by activated T cells express the T8 determinant. In contrast, we have previously shown that less than 10% of T cells activated after 6 days in culture with non-T cells express the T8 determinant. The number of T8 bearing cells were increased significantly after 10 days in culture with non-T cells. This suggested that two types of reactions, the {T:Non-T} and {T:T act} AMLR, might occur in sequence when T cells and autologous non-T cells are cocultured: first, the activation of T4 cells by non-T cells, then by the activation of T8 cells by activated T4 cells. Finally, activated T cells can stimulate unfractionated autologous mononuclear cells without prior exposure to sheep erythrocytes or fetal calf serum. 相似文献
108.
Lines of mouse-human hybrid cells segregating either mouse or human chromosomes were used for the analysis of various aspects of the production and actions of mouse and human interferons. In one of the hybrid cell lines capable of producing both mouse and human interferons, the proportion of the two interferon activities produced varied greatly under different inducing conditions, suggesting that there are differences in the triggering mechanisms of the two interferons. Generally both mouse and human interferon production could be enhanced (“superinduced”) by sequential treatment with cycloheximide and actinomycin D; however, in one of the lines producing both mouse and human interferon, only the latter could be superinduced. There was no correlation between the capacity of the lines to produce mouse or human interferons and the sensitivity to their action. However, there was good correlation between the sensitivity to the antiviral action and the priming action (i.e., enhancement of subsequent interferon production) by the two interferons. Thus, line 55-91F2 produced both mouse and human interferons, but was sensitive to the antiviral and priming actions of human interferon only. Line GM52 × BalbVC15 produced only mouse interferon but was sensitive to the antiviral and priming actions of both interferons. 相似文献
109.
Maturation of pyramidal cell form in relation to developing afferent and efferent connections of rat somatic sensory cortex. 总被引:3,自引:0,他引:3
Golgi and axonal labeling methods were used to examine the maturation of pyramidal cells in layers III and V of the rat somatic sensory cortex. The material came from animals late in the gestation period, postnatal, ranging from 0 to 43 days of age and at maturity. Special attention was paid to the period (0–7 days of age) during which it is known that thalamic and callosal fibers grow into the cortex. It is shown that the basic features of the pyramidal cell form are established before the long afferent fibers arrive in layers III and V and before the large number of synapses are established in these layers. Nevertheless, considerable dendritic growth and spine formation occurs after the afferent fibers establish an adult-like pattern of distribution. It is also shown that even at 1 day of age, the axons of pyramidal cells in all layers have reached the vicinity of targets such as the striatum, thalamus, brainstem, spinal cord and contralateral cortex.At 0–1 day the immature pyramidal cells are essentially bipolar in the upper cortical plate, but in the developing infragranular layers they have a few short, almost spine-free, basal dendrites and, rarely, a few oblique branches of the apical dendrite. The apical dendrite extends to the pial surface and the dendritic branches end in growth cones. The dendrites of cells in all layers increase in size and complexity of branching over the first postnatal week; the maturation of dendrites in layer V leads that of dendrites in the supragranular layers by about 2–3 days. As maturation proceeds, basal dendrites acquire secondary and tertiary branches and more oblique branches appear on the apical dendrite. Dendritic spines appear after 4 days of age but remain sparse up to 7–8 days. At 14 days of age, the spine density is much higher than in 7-day-old animals but remains at a much lower density than in 4-week-old, 6-week-old, or adult animals. By 7–14 days, the difference in maturity between superficial (layer III) and deep (layer V) pyramidal cells is difficult to discern qualitatively. All the pyramidal cells now have relatively complex, highly branched dendritic trees when compared to younger cells, but the dendritic tree is still immature in terms of the number, length and complexity of branching of the apical and basal dendritic systems.It can be concluded that the growth of the long axon of cortical pyramidal neurons precedes the acquisition of afferent connections and when these afferent fibers arrive in the cortex the dendritic tree of the pyramidal cell is still highly immature. Thus it remains possible that the finer modeling of the dendritic tree and the formation of spines may be affected by extrinsic influences such as the afferent fibers. 相似文献
110.
Charles R. Bursey Stephen R. Goldberg 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2007,52(4):368-370
Aplectana krausi sp. nov. (Ascaridida, Cosmocercidae) from the intestines of Platymantis boulengeri (Anura, Ceratobatrachidae) is described and illustrated. Aplectana krausi represents the 42nd species assigned to the genus, the 4th species reported from the Australo-Papuan region. It is easily
separated from the three species previously reported from the region by the distribution pattern of male caudal papillae:
A. macintoshii and A. novaezelandiae have irregular patterns; A. zweifeli and A. krausi have defined patterns. Aplectana zweifeli has 8–10 precloacal, no adcloacal, and 9 postcloacal pairs of papillae, there is a single median papillae just anterior to
the cloaca; A. krausi has 5 precloacal, 1 adcloacal, and 5 postcloacal pairs of papillae, a median papillae is absent. 相似文献