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991.
Computer competition analysis of 3H-DHA (3H-dihydroalprenolol, a nonselective beta-adrenergic radioligand) binding in the presence of unlabeled metoprolol (a beta 1-selective antagonist) indicates the existence of both beta 1- and beta 2-adrenergic receptor subtypes in the rat placenta and confirms previous reports that both beta-adrenoceptors are present in adult rat cortex. In the fetal brain (20th day of gestation), however, only beta 1-receptors were detected. Pregnant rats were chronically exposed to methadone from day 7 to day 20 of gestation via implanted osmotic minipumps (6.3-9.0 mg/kg/day). This treatment schedule did not induce a change in the affinity and density of either beta-receptor subtype in the placental, fetal and maternal brain homogenates. The results are discussed in terms of the reported monoaminergic and opiate receptor functional interactions. 相似文献
992.
Therapy of human cervical carcinoma with monoclonal antibody-Pseudomonas exotoxin conjugates. 总被引:1,自引:0,他引:1
Pseudomonas exotoxin A (PE) linked to the F(ab')2 fragment of 1H10, a murine monoclonal antibody recognizing a carbohydrate epitope of a glycoconjugate expressed on the surface of human cervical carcinoma tumor cells, was evaluated for in vitro and in vivo activity. PE can kill cells by ADP-ribosylating elongation factor 2 thus inhibiting protein synthesis. Disulfide- as well as thioether-linked immunotoxins (1H10-PE) killed cervical carcinoma cells in vitro and were 20-160 times more inhibitory to target than to control cells. Cell killing was antibody mediated as demonstrated by the reduction of 1H10-PE growth inhibition to target CaSki cells by free 1H10 F(ab')2. In addition, a control antibody immunotoxin was nontoxic to CaSki cells. Thioether-linked 1H10-PE administered either i.v. or i.p. suppressed the growth of established solid s.c. cervical carcinoma tumors xenografted in nude mice for over 30 days. Treatment with antibody alone or a control immunotoxin had no significant effect on tumor growth. Administration of immunotoxin i.p. was associated with less toxicity than administration i.v., but i.v. injections were more effective at suppressing the growth of established solid tumors. 相似文献
993.
The analysis of vestibular responses in a comatose patient often provides the critical information for making a correct preliminary diagnosis and directing the subsequent laboratory evaluation. Because of some uncertainties about what is being tested with the various bedside maneuvers that are used to elicit vestibular responses, we review the physiologic basis for the oculomotor responses that occur with head rotation or with caloric stimuli. We further urge precise and unambiguous terminology to describe both stimulus and response. We suggest using physiologically well-defined terms such as vestibulo-ocular reflex and cervico-ocular reflex and avoiding potentially misleading terms such as the doll's head and the oculocephalic maneuvers. 相似文献
994.
C P Baveja D Chattopadhya S Kumari K K Dutta S Sehgal 《The Journal of communicable diseases》1989,21(1):59-61
Sixty drinking water samples collected from various sources in different areas of Delhi during epidemic of cholera and gastroenteritis were analysed for bacteriological standards. Only 27 (45 per cent) samples were found to be satisfactory for human consumption. Remaining thirty-three (55 per cent) samples showed presence of coliform organisms with MPN value ranging from 10 to 1800+ per 100 ml. Among these positive samples, 31 (93.9 per cent) samples contained faecal coli. Twenty out of thirty (66.6 per cent) Hand pump, 9 out of 21 (42.8 per cent) Taps 2 out of 4 (50 per cent) Tube well and 2 out of 5 (40 per cent) of miscellaneous sources showed contamination with coliform organisms. 相似文献
995.
996.
997.
A rare case of craniopharyngioma extending to the cranial base and nasopharynx is reported and eight other cases in the literature are reviewed. The embryology and the clinical features of these tumors are discussed. Tomograms of the skull and computed tomography are the most useful radiological tools of investigation. A nasoseptal or transpalatal approach to surgery, which has been performed in reported cases of cystic nasopharyngeal craniopharyngiomas, was not performed on our patient because of the hard consistency and the diffusely infiltrating aspect of the tumor. 相似文献
998.
A patient with long-standing Tourette's syndrome had a dramatic exacerbation of symptoms following the rapid withdrawal of haloperidol. Clonidine administration resulted in a disappearance of tics, which recurred 6 days later. The role of clonidine in blocking withdrawal-induced symptoms in patients with Tourette's syndrome treated with long-term neuroleptics is discussed from a clinical and neurobiological perspective. The implications of this case for the treatment of supersensitivity psychosis and tricyclic withdrawal states with clonidine are also discussed. 相似文献
999.
S Kam-Hansen 《Journal of the neurological sciences》1986,75(3):285-292
A young woman is described who had myasthenia gravis which was favourably influenced by thymectomy. Although there was no evidence for another neurological disease over 7.5 years of clinical observation and computed tomography as well as visual evoked response were normal, CSF studies over 0.5 years prior to and 3.5 years after thymectomy revealed persistent mononuclear pleocytosis, high CSF IgG index, oligoclonal IgG bands in CSF, and increasing IgG synthesis rate within the CNS, reflecting a continuous local humoral immune response. CSF/serum ratios of antibodies to acetylcholine receptors (AChR) were continuously lower than CSF/serum IgG ratios, contradicting intrathecal AChR antibody production. Proportion of total T cells was slightly higher in CSF than peripheral blood, while active T cells were lower in CSF. CSF lymphocytes did not proliferate on PHA stimulation but responded in allogeneic mixed lymphocyte culture. B cells were 4% in CSF and 4.5% in peripheral blood, but 227 IgG, 0 IgA and 0 IgM producing cells were detected among 20 X 10(3) CSF lymphocytes, compared to 5, 4 and 0 in 20 X 10(3) peripheral blood lymphocytes. This patient represents an in vivo 'experiment' regarding influence of thymectomy on CSF compartment constituents. The present study also shows that an individual can be clinically healthy despite continuous and pronounced intrathecal immune response. 相似文献
1000.
Effectiveness and nutritional consequences of amino acid-based vs glucose-based dialysis solutions in infants and children receiving CAPD 总被引:2,自引:0,他引:2
Excessive glucose absorption and dialysate amino acid and protein losses contribute to malnutrition in children on glucose-based continuous ambulatory peritoneal dialysis (CAPD). We used 2.5 and 4.25% glucose and 1.1 and 2.0% amino acid dialysates to assess short-term effectiveness and nutritional consequences of amino acid-based dialysis solutions. Plasma and effluent urea and creatinine concentrations were similar with amino acid and glucose dialysis although 16% less fluid was removed with amino acid dialysates. Absorption of 77.3 +/- 5.3% of dialysate amino acids exceeded losses of amino acids and protein in glucose effluent. With amino acid dialysates, fasting plasma glucose concentrations were maintained while plasma amino acid levels rose, peaked at 1 h, and, excepting methionine, isoleucine, and phenylalanine with the 2.0% solution, returned to initial levels after 5 h. Compared with glucose, amino acid dialysates provide reduced but satisfactory fluid and waste removal, maintain normoglycemia, and more than compensate for effluent losses of amino acids and protein. 相似文献