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971.
972.
Tímár J  Paku S  Kopper L 《Orvosi hetilap》1999,140(51):2869-2871
The effect of a widely used trace element preparation (Béres-Drop Plus, BDP) on the liver metastasis forming potential of 3LL-HH tumor was studied. The daily, oral administration of BDP caused a decrease in the number of liver metastases, irrespective of the presence or absence of the primary spleen tumor. It is suggested, that the zinc component of BDP is responsible, at least partly--for the inhibitory action.  相似文献   
973.
Interferon-beta-1b was the first drug found to slow the progression of relapsing-remitting multiple sclerosis, with a reported decrease in the relapse rate of up to 34%. The present study involved 35 patients treated with interferon-beta-1b for one year. The aims of the study were: a) to compare the changes in the relapse rate and the number of days of hospitalization with other data, b) to compare the steroid needs required to treat relapses for one year before and in the year of interferon-beta-1b treatment. Our data indicated that the relapse rate may decrease as much as 77% following the introduction of interferon-beta-1b treatment. The adverse effects and the changes in the EDSS grades were similar to the published data. The duration of hospitalization decreased by 84% and the amount of methylprednisolone needed for remission by 78%. This data suggest that the impairment of the condition of the patients may be delayed considerably, while some of them can continue to work for a longer period, the standard of life of these patients therefore being more tolerable.  相似文献   
974.
This paper emphasizes the creation and application of a KIT for the communication of occupational accidents with puncture-cutting objects to the Municipal Health Bureau from the city of Ribeir?o Preto. It is an essential instrument for the health care services directed to all the employees of the Health Units. It also evidences the notification and the beginning of the prevention of occupational diseases, being a highly useful instrument whenever any accident occurs. The creation of this KIT enabled the use of prevention measures regarding occupational diseases, culminating with the mobilization of the chiefs and the staff in order to intensify preventive procedures.  相似文献   
975.
Health is one of the basic requirements for improvement in the quality of life. Since Bangladesh became independent, a policy for providing essential minimum health care to all has been actively pursued. An overview of Public Health Services in Bangladesh is presented in terms of: (1) a profile of the country, (2) an overview of public health, (3) medical care, and (4) environmental health. Under each of these headings observations are included on recent trends based upon relevant data and information. Finally the authors describe the importance of (1) promotion of health care and planning at the national, divisional, local, and community levels, (2) promotion of medical services at all levels, and (3) effective decentralization of health services to enhance the services of health facilities.  相似文献   
976.
The value of the γ-aminobutyric acid (GABA) receptor of nematodes as a target for ivermectin's mode of action remains unclear. Using binding assays, we examined extracts from Trichinella spiralis muscle larvae for the presence of [3H]-ivermectin and [3H]-GABA binding sites. Tissue preparations displayed affinity binding sites for [3H]-ivermectin with a dissociation constant (K d) of 83 nM and a receptor density (Bmax) of 145 fmol/mg protein. We also identified a specific [3H]-GABA binding activity with a K d of 1.2 μM and a Bmax of 4.78 pmol/mg protein. In competition studies, ivermectin was found to be a competitive inhibitor of specific [3H]-GABA binding activity with an inhibition constant (K i) of 3.39 nM, suggesting that GABA receptors could be implicated in the mechanism of action of ivermectin in nematodes. Received: 7 August 1998 / Accepted: 22 September 1998  相似文献   
977.
The question of whether thyroxine (T4) and thyrotropin-releasing hormone (TRH) affect mitoses in pituitary thyrotrophs (Tt) and somatotrophs (St) of hypothyroid rats was investigated. Fifteen day thyroidectomized (Tx) rats were used. Groups of Tx animals received T4 or TRH or both. Except 6 and 24 h TRH groups, the animals were sacrificed 12 h after injections. Unoperated euthyroid rats served as controls. In Tx group adenohypophysial mitoses were significantly increased. T4 diminished mitoses in Tx rats. Mitotic counts were decreased in 6 and 24 h Tx groups, but increased in 12 h TRH group. TRH plus T4 in Tx animals had a synergistic effect on adenohypophysial mitoses. In unoperated controls few mitoses were observed in Tt and more mitoses in St. In Tx rats more mitoses were seen in Tt than in St. T4 alone failed to reduce mitoses in Tt but increased them in St. We concluded that T4 affects Tt and St replication. In normal rats mitoses occur mainly in St. In Tx rats mitotic activity increased in Tt. TRH plus T4 have a synergistic motogenic effect on St. T4 but not TRH affects St replication. It appears that the presence, of T4 is necessary for St multiplication.  相似文献   
978.
It is thought that monocyte-macrophages and probably dendritic cells play a central role in HIV-1 primary infection, as well as in its evolution, given that they are among the first cells infected and later function as important reservoirs for the virus. These cells may participate in the selection of certain viral strains instead of others. Levels of CCR5 coreceptor expression on the surface of monocytes and macrophages determine their susceptibility to infection by HIV-1 strains using this coreceptor and may explain, in part, the differences in the infectivity of these cells through the maturation process. However, selection for certain strains is not only determined by the level of coreceptor expression, but by the biochemical properties of the different coreceptors and their relationship with other surface molecules and the chemokine and cytokine networks, which also influence the selective viral infection and replication in these cells. Any current or newly designed therapies need to be evaluated, including careful analysis of the levels of HIV-1 infection of the cells of the monocyte-macrophage lineage, because these cells are both significant viral reservoirs and a center of virus production at all stages of the disease.  相似文献   
979.
Four groups of rats were inoculated with Streptococcus sobrinus ATCC 33478 and fed a cariogenic diet for 42 days. Topical treatment with either distilled water, sodium fluoride (0.2%), a solution containing lactoferrin and lactoperoxidase, or a solution containing liposome-encapsulated lactoferrin and liposome-encapsulated lactoperoxidase was applied at intervals for 35 days. Caries incidence in groups treated with liposome-encapsulated lactoferrin and lactoperoxidase was significantly lower than in control groups. The number of viable Strep. sobrinus and the proportion of Strep. sobrinus in the total counts were significantly higher in liposome-treated groups. Free lactoferrin and lactoperoxidase did not cause a significant reduction in caries incidence.  相似文献   
980.
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