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991.
Weaver mutant mice are characterized by a decrease in striatal dopamine (DA), which is associated with a progressive loss of DA neurones in the substantia nigra. This mutant thus provides the opportunity to examine the functional effects of DA neurones grafted to the striatum in a genetic model of parkinsonism. Ventral mesencephalic tissue from normal foetuses was placed on the surface of the right dorsal striatum of adult weaver mutants. After grafting, animals were tested for methamphetamine-induced circling behaviour. Mutants with DA containing grafts displayed a significant circling bias toward the left, non-grafted side. Mutants without grafts did not display any rotational bias to either side. These results demonstrate that grafted DA containing neurones establish a functional innervation of the weaver striatum and suggest that grafting of neural tissue is a viable approach in restoring function in genetic degenerative disorders of the nigrostriatal system. 相似文献
992.
Characterization of gp 50, a major glycoprotein present in rat brain synaptic membranes, with a monoclonal antibody 总被引:4,自引:0,他引:4
Philip W. Beesley Toni Paladino Claude Gravel Richard A. Hawkes James W. Gurd 《Brain research》1987,408(1-2):65-78
Several cell lines secreting monoclonal antibodies (Mabs) against a major forebrain synaptic membrane (SM) glycoprotein, gp 50, have been raised. Western blots show that the Mabs react with a polypeptide doublet of Mrs 49 and 45 kDa. These polypeptides exist solely in a concanavalin A (Con A) binding form. Removal of the Con A receptors by digestion with endo-beta-N-acetylglucosaminidase H (endo H) lowers the Mrs of the glycoprotein doublet to 36.5 and 34 kDa. Western blots of 2D polyacrylamide gels indicate that gp 50 exists in several isoforms. Solid phase radioimmunoassay (RIA) and Western blots of brain subcellular fractions show the antigenic material to be concentrated in the SM fraction, but to be present in much lower amounts in synaptic junctions and postsynaptic densities. Gp 50 appears to be brain specific. Regional distribution studies show that it is present in all brain regions but is two-fold concentrated in cerebellum, brainstem and midbrain compared to forebrain. Immunocytochemical studies of several brain regions show that gp 50-like immunoreactivity is neuron specific and is concentrated in selected neuronal species, particularly granule cells. In both cerebellar and hippocampal granule cells gp 50-like immunoreactivity is localized in the perikarya and primary dendrites. Though immunocytochemistry did not show staining of synaptic regions this may be due to masking of the reactive epitope. The results are discussed in terms of the molecular properties of gp 50 and its subcellular localization in brain tissue. 相似文献
993.
994.
G Pelletier A M de Passillé M Bernier-Cardou J Morisset 《The Journal of nutrition》1987,117(10):1759-1766
In the first experiment, 52 sows, each having raised one litter, were randomly assigned to the five following groups: control (nongravid) for pregnancy (CP), 110 d pregnancy (P110), control (nongravid) for lactation (CL), 4-wk lactation with 8 (L8) and with 12 (L12) piglets. In a second experiment, 36 sows, each having raised three litters, were randomly assigned to the following groups: control group (nongravid) fed a low-energy-density, 1% tallow diet (CLED) and two lactating groups, one fed the low-energy-density diet (LLED) and one fed a high-energy-density, 10% tallow diet (LHED). At slaughter, the stomach, small and large intestine and cecum were excised, emptied and freed from fat. Lengths and pre- and post-defatting weights were measured. Portions of tissues were homogenized and analyzed for protein, pepsin, maltase, RNA and DNA. Pregnancy had no effect on the weights of the different components of the gastrointestinal tract. Liver and small intestine weights were larger in lactating sows than in the CL group. Sows nursing 12 piglets had heavier livers than those nursing 8. The fundic mucosa of the latter had higher total pepsin activity and total protein and RNA contents than that of L12 sows. LHED sows had heavier small intestine and lower total pepsin content of the fundic mucosa than LLED sows. 相似文献
995.
A H Myers B Rosner H Abbey W Willet M J Stampfer C Bain R Lipnick C Hennekens F Speizer 《American journal of public health》1987,77(5):628-630
We analyzed smoking behavior of 91,651 married female nurses, aged 30-55 years in 1976. The prevalence of smoking was similar among all birth cohorts. The largest percentage increase in starting to smoke occurred between ages 15 and 25 years; by age 25, 50 per cent had started smoking. The cessation rate was lowest in earlier birth cohorts and among nurses starting to smoke at earlier ages. The cessation rate increased substantially between 1963-73 compared with the period 1948-58. 相似文献
996.
997.
998.
This study evaluated health risks associated with U.S. Navy submarine duty by comparing hospitalization rates of submariners with surface ship personnel. The groups were compared using age-adjusted hospitalization rates for 16 major diagnostic categories and several specific diagnoses postulated to be submarine associated. Submarine personnel did not have significantly higher hospitalization rates for any diagnostic categories nor for any of the submarine-associated illnesses. Submariner relative risk of hospital admissions was greater for a few selected diagnoses but statistical significance was not attained. Submarine personnel had lower hospitalization rates for nearly all of the diagnostic categories examined. Reasons for these lower rates may be stringent screening of submariners, higher levels of education among submariners, difficulty of evacuation from a submarine, and the healthy-worker effect. The health status of U.S. Navy personnel does not seem to be adversely affected by submarine duty. 相似文献
999.
Effects of danazol on mineral homeostasis in normal postmenopausal women: preliminary communication.
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The effects of danazol on calcium homeostasis in normal postmenopausal women was examined in a 14-day study utilizing a dosage of 800 mg per day. Danazol caused significant falls in plasma ionized calcium and in the fasting urinary calcium/creatinine ratio, indicating inhibition of bone resorption. Retention of phosphate was also observed as expected with this anabolic agent. The plasma total alkaline phosphatase was also depressed by the drug, which had no effect on hepatocellular function as measured by plasma AST. Certain effects induced by treatment with danazol were still apparent two weeks after cessation of treatment. The drug was well tolerated and androgenic side effects were not seen. It is suggested that the minimal dose regimen of danazol which exerts a calcium-sharing effect should be identified, and that this regimen should be considered for use in a prospective study of the effects of danazol on bone mineral content in the postmenopause. 相似文献
1000.
A V Pokrovski? P O Kazanchian G I Kuntsevich V L Buianovski? M A Vikhert 《Vestnik khirurgii imeni I. I. Grekova》1986,137(9):56-64
Results of an examination of 39 patients are described and critically assessed. An analysis of the resolving power of the method of ultrasonic angiography in pathological formations of major vessels of the neck is given. 相似文献