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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
A new approach to the activation of reactants during the condensation of aromatic aldehydes with N-aroylglycines (acting as
CH-acids) is described. The condensation reaction carried out on heating in phosphorus oxychloride leads to a high yield of
4-benzylideneoxazol-5-one derivatives. The hydrolysis of these intermediate products yields the target α-benzoylaminocinnamic
acids.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 7, pp. 41 – 42, July, 2005. 相似文献
994.
Transplantation of microencapsulated bovine chromaffin cells reduces lesion-induced rotational asymmetry in rats 总被引:7,自引:0,他引:7
Surrounding bovine chromaffin cells by a semipermeable membrane may protect the transplanted cells from a host immune response and shield them from the inflammatory process resulting from the surgical trauma. Encapsulation of the chromaffin cells was achieved by inter-facial adsorption of a polycation on a polyanionic colloid matrix in which the chromaffin cells were entrapped. Basal and potassium-evoked release of catecholamines from encapsulated bovine chromaffin cells was analyzed over a 4-week period in vitro. Norepinephrine and dopamine release remained constant over time whereas epinephrine release significantly decreased. The chromaffin cells also retained the capacity for depolarization-elicited catecholamine release 4 weeks following the encapsulation procedure. Morphological analysis revealed the presence of intact chromaffin cells with well-preserved secretory granules. Striatial implantation of chromaffin cell-loaded capsules significantly reduced apomorphine-induced rotation compared to empty polymer capsules in animals lesioned with 6-hydroxydopamne frr at least 4 weeks. Intact chromaffin cells expressing tyrosine hydroxylase and dopamine-β-hydroxylase were observed in all capsules implanted in the striatum for 4 weeks. The assessment of the clinical potential of transplanting encapsulated adrenal chromaffin cells of either allo- or xenogeneic origin for Parkinson's disease will require long-term behavioral studies. The present study suggests, however, that the polymer encapsulation procedure may offer an alternative to adrenal autografts as a source of dopaminergic tissue. 相似文献
995.
We conducted a double blind controlled trial in 28 Duchenne muscular dystrophy (DMD) patients with Deflazacort (DF), an oxazoline derivative of prednisolone which reduces its side-effects. Myometric muscle strength measurements, Scott Score and timed tests showed statistically significant improvement for the treated group (P less than 0.05). Side-effects after 9 months of treatment included mild cushingoid appearance in four patients (28%) and moderate in only one (7%), increased appetite in seven (50%), increased body hair in four (28%), irritability and hyperactivity in three (21%). Increased body weight was not prominent and was controlled with dietary measures. No patient had to be withdrawn from medication. More research and long-term follow-up are needed in order to establish the mechanism of improvement and the consequences of long-term steroid administration in DMD. In this regard DF appears as an alternative to prednisone preserving its benefits but with fewer side-effects. 相似文献
996.
J W McDonald E A Garofalo T Hood J C Sackellares S Gilman P E McKeever J C Troncoso M V Johnston 《Annals of neurology》1991,29(5):529-541
We examined binding to excitatory amino acid and inhibitory amino acid receptors in frozen hippocampal sections prepared from surgical specimens resected from 8 individuals with medically refractory temporal lobe epilepsy. The excitatory receptors studied included N-methyl-D-aspartate (NMDA), strychnine-insensitive glycine, phencyclidine, and quisqualate. The inhibitory receptors studied were gamma-aminobutyric acid type A (GABAA) and benzodiazepine. Excitatory and inhibitory amino acid receptor binding were differentially altered in the patients with temporal lobe epilepsy in comparison to 8 age-comparable autopsy control subjects, and changes in receptor binding were regionally selective in four areas. Binding to phencyclidine receptors associated with the NMDA channel was reduced by 35 to 70% in all regions in the hippocampi of the patients. In contrast, binding to the NMDA recognition site and its associated glycine modulatory site was elevated by 20 to 110% in the cornu ammonis (CA) 1 area and dentate gyrus of the hippocampus of the patients. Binding to these sites was unaffected in area CA4. Binding to the quisqualate-type excitatory amino acid receptor was unchanged in all regions except the stratum lacunosum moleculare CA1, where it was increased by 63%. GABAA and benzodiazepine receptor binding was reduced by 20 to 60% in CA1 and CA4, but unchanged in dentate gyrus. The data indicate that excitatory and inhibitory amino acid receptors are altered in the hippocampus of patients with temporal lobe epilepsy. 相似文献
997.
Increased lymphocyte beta-adrenergic receptor density in progressive multiple sclerosis is specific for the CD8+, CD28- suppressor cell. 总被引:1,自引:0,他引:1
Beta-adrenergic receptor density on T cells from healthy humans is greatest on suppressor cells (CD8+, CD28-) and the effect of catecholamines, secreted by the sympathetic nervous system, predominates on this subset. The sympathetic skin response, a measure of sympathetic nervous system function, is absent in most patients with chronic progressive multiple sclerosis (MS). We measured beta-adrenergic receptor density on suppressor cells, cytotoxic cells, and monocytes from patients with chronic progressive MS and healthy control subjects. Control receptor density on suppressor cells was 2.8 +/- 0.3 fmol/10(6) cells versus a density of 5.1 +/- 0.7 fmol/10(6) cells for patients. Cytotoxic cell (CD8+, CD28+) receptor density was 1.4 +/- 0.4 fmol/10(6) cells in control subjects and 0.9 +/- 0.3 fmol/10(6) cells in the patients. Monocytes displayed beta-adrenergic receptor densities of 2.6 +/- 0.4 fmol/10(6) cells in normal individuals and 2.7 +/- 0.4 fmol/10(6) cells in the patient group. CD8 lymphocyte beta-adrenergic receptor densities in patients with relapsing-remitting and those with stable MS were not different from control values, yet were significantly less than the values for patients with chronic progressive MS. We find that mononuclear cells from healthy control subjects and patients with chronic progressive MS proliferate in response to 200 units/ml of recombinant human interleukin-2 (IL-2) similarly. However, IL-2 treatment increased beta-adrenergic receptor density on normal mononuclear cells, but failed to increase it on mononuclear cells from patients with chronic progressive MS.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
998.
Artificial dopamine agonists are widely employed for the treatment of idiopathic parkinsonism. Pleuropulmonary disease has previously been reported to occur with the use of bromocriptine and mesulergine. We report similar adverse effects induced by the newer agonists lisuride and cabergoline. All these agents are tetracyclic ergot derivatives. This suggests a causal link between ergot-derived dopamine agonists and pleuropulmonary disease. 相似文献
999.
In acute experiments on cats the activity of the motor cortex neurons was recorded. The dynamics of interneuronal connections at passive bending and electrostimulation of the limb contralateral to the place of recording was studied by methods of cross-correlation analysis of impulse trains. At passive bending a considerable decrease of the number of common inputs between neighbouring neurons (within 50-100 microns) and an increase in their number between remote (from 100 till 400 microns) cortical neurons. During electro-stimulation a certain increase in the number of direct inhibitory interactions between the neighbouring neurons was observed. 相似文献
1000.
Computer tomography (CT) of the brain is of value for finding potentially correctable lesions in adult patients with new onset seizures. The value of CT is unknown, however, for finding such lesions in adult chronic epileptic patients without prior CT. We compared a group of 177 adult patients who had CT within a year from the onset of seizures to a group of 93 patients who had a history of seizures for more than a year before CT was performed. In the first group, 33 potentially correctable lesions (19%) were found including 17 tumors. The group with chronic epilepsy had 4 (4%) potentially correctable lesions: 3 arteriovenous malformations and 1 meningioma. It seems that CT is of value in discovering potentially removable lesions in chronic epileptic patients, but the likelihood is relatively small. The incidence of stable structural lesions seems to be similar in the two groups. 相似文献