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991.
Calcitonin suppresses food and water intake. To further study this effect of calcitonin, rats were subjected to various intra-cerebroventricular (ICV) applications of calcitonin. The results show: (1) Intra-third ventricular (III-ICV) infusion of calcitonin dose-dependently decreased food intake with short- and long-term effects; (2) Potency was decreased by using non-siliconized materials; (3) Potency decreased with age of rats; (4) Infusion into the aqueduct and cisterna magna decreased short- and long-term food intake less than III-ICV administration; (5) Aqueduct obstruction did not affect feeding suppression by III-ICV calcitonin. Aqueduct obstruction did not affect dipsogenic response to III-ICV infusion of angiotensin II; (6) Results of water intake and food to water intake ratios suggest a greater calcitonin effect on food intake than on water intake. The evidence suggests that the hypothalamus is a main locus for suppression of food intake by ICV administered calcitonin.  相似文献   
992.
993.
A rare kind of a breast tumor was identified in a woman of 47. The disease ran a malignant course and presented difficulties for morphological verification. Histological appearance showed areas of spindle-shaped or lamellar cells occasionally encircled with homogeneous hyalin-like substance. Locally, there were structures of alveolar or glandular type with an irregular basal membrane and loose position of cells. The primary histological diagnosis suggested a tumor of mesenchymal origin. Followed by immunomorphologic (monoclonal antibody to KL 1) and electron-microscopic examinations, the diagnosis was verified providing evidence for epithelial nature of the tumor cells, loose, forming glandular-like structures and simulating stromal elements with ultrastructural features typical of myoepithelial differentiation. The evidence obtained justify the tumor definition as a rare neoplasm of the breast known in the literature as myoepithelioma.  相似文献   
994.
Dopaminergic mechanisms were Anatyzed in an isolated preparation of the turtle olfactory bulb. Field potentials were evoked by antidromic or orthodromic stimulation, and the effects determined of pharmacological manipulations of the bathing medium. In the presence of dopamine or a dopamine agonist, apomorphine, there was a reduction of amplitude and delay of onset of the component of the field potentials due to granule cell responses; fluphenazine, a dopamine antagonist, had generally opposite effects. Using paired volleys, it was found that the suppression of the response to the second test volley was reduced in the presence of dopamine or apomorphine, but enhanced in the presence of fluphenazine.The most likely explanation of these results is that exogenous dopamine depresses the response of mitral cells, which in turn decreases the dendrodendritic synaptic excitation of granule cells and reduces their inhibitory feedback onto mitral cells. This suggests that the dopaminergic cells in the bulb may suppress mitral cells by modulating excitable mechanisms in the mitral dendritic membrane, or modulating long-lasting synaptic potentials.  相似文献   
995.
996.
Heats of mixing with water as function of the composition of the mixtures for oligomeric models of poly(oxyethylene) at 25°C are reported, i. e. for compounds of the type XO(CH2CH2O)nX (where X = H or CH3 and n = 1, 2, 3, or 4) and CH3O(CH2CH2O)mH (where m = 1 or 2). These dependencies greatly depend on the character of the end groups and on the degree of oligomerization. A procedure has been suggested for the comparison between the heat of mixing of longer chains and that of shorter ones with elimination of the effect of end groups. On the same mass basis, longer chains release more heat than shorter ones in mixing with water for concentrated solutions; hence, one may assume some kind of cooperativity of ether oxygen atoms in the same chain by hydration.  相似文献   
997.
In cases of missing outer ears, generally, epistheses are attached to eye-glasses which gives insecure attachment and a fairly poor cosmetic result. A new method for stable episthesis attachment is being tested in Gothenburg, Sweden. Threaded, cylindrical titanium implants are inserted with a meticulous technique in the temporal bone of the patient. At the next stage, 3–4 months later, the implants are connected to abutments which are allowed to penetrate the skin, To these abutments a silicone episthesis is attached. Presently, 7 patients who had no outer ear because of congenital disorders, hereditary diseases or status post trauma or tumour surgery have been operated and followed for up to 12 have been no problems reported with the bone anchorage or the skin penetration.  相似文献   
998.
Analysis of HLA DRB1 and DQB1 Bam HI RFLPs revealed four DRB1 (4.8, 5.2, 6.0 and 7.0 kb) fragments and a 3.2 kb DQB1 fragment to be significantly increased in Caucasians with seropositive RA compared to healthy individuals. The 4.8, 5.2 and 7.0 kb DRB1 fragments were found in 86.5% of RA patients and in 56% of the controls (p = 10(-3), relative risk (RR) = 5.0), while the 6.0 kb fragment was found in 79% of RA patients compared to 32% of controls (p = 2 x 10(-5), RR = 8.0). The 3.2 kb DQB1 fragment was observed in 63.5% of RA patients versus 38.0% of controls (p = 10(-2), RR = 2.8). Analysis of these fragments relative to HLA phenotypes revealed that the 4.8, 5.2 and 7.0 kb DRB1 fragments were strongly correlated with DR4, -7, -9 and -w53 serotypes, the 6.0 kb RFLP with DR4 and the 3.2 kb DQB1 fragment with DR1 and DQw1. Using probes specific for the 5' or 3' regions of the DRB1 gene, the 5.2 and 6.0 kb DRB RFLPs were mapped to the 5' end and the 4.8 and 7.0 kb RFLPs to the 3' end of the DRB1 gene. A probe generated from the second exon of the DRB4 (DRw53) gene recognized only the 5.2 and the 6.0 kb RFLPs corroborating the 5' location of these RFLPs. Family studies further confirmed that these RFLP's segregated with HLA phenotypes.  相似文献   
999.
A dysfunction of amino acid neurotransmitter transporters occurs in a number of central nervous system disorders, including stroke, epilepsy, cerebral palsy and amyotrophic lateral sclerosis. This dysfunction can comprise a reversal of transport direction, leading to the release of neurotransmitter into the extracellular space, or an alteration in transporter expression level. This review analyses the role of glutamate and GABA transporters in the pathogenesis and therapy of a number of acute and chronic neurological disorders.  相似文献   
1000.
KIR and HLA loci are both highly polymorphic, and some HLA class 1 products bind and trigger cell-surface receptors specified by KIR genes. We examined whether KIR genes act in concert with HLA-B locus to control HIV-1 infection in a sample of Zambian patients. DNA samples from 88 Zambian patients with HIV-1 were examined. Patients were classified as either slow progressors (SP; n = 54) or rapid progressors (RP; n = 34) to AIDS. All were typed for HLA-B and KIR genes. Our results reveal an association between B*57 supertype (B*57s, which includes B*57 and B*58 alleles) and delayed progression to AIDS (p = 0.0007 by pc = 0.015; OR = 5.25). We also observed an increase incidence of Bw4-I80 in patients with slow progression (p = 0.001 by pc = 0.003, OR = 5). This increase was found to be secondary to B*57s. The presence of both KIR3DL1 and B*57S has a significant effect on progression to AIDS (p = 0.0008; OR = 5.61). B*57s genotypes with another HLA-B allele different from those in the trans position, which also had a specificity different to Bw4-I80 (Bw4-T80 or Bw6), was also greater in the SP than in the RP group (p = 0.00003; OR = 10.11). The presence of the inhibitory allele KIR3DL1 in combination with the HLA-B*57s alleles that contain the Bw4-I80 epitope, has a highly protective effect against progression to AIDS in Zambian patients.  相似文献   
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