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991.
The contributors propose a set of newly performed hygienic studies in the widely developed technologies of electrotype, expound a complex of the hazardous occupational factors commonly encountered in modern galvanoplastics, contamination of the equipment, overalls and the skin with the metallic compounds contained in the galvanic electrolytes. Shops with non-isolated electrotype lines were characterized by the most unfavourable labour conditions.  相似文献   
992.
The following pages try to offer some ways of arguing against pesimism in our health administration culture. In fact, the review of a wide range of feasible reforms of our health system undertaken in this paper gives some clues for a better implementation of the a priori advantages of public health systems. These advantages are not achieved today because of some dysfunctionalities of daily management. To rationalize resources distribution, to evaluate the results, to eliminate unnecessary administrative control, to coordinate responsibility and budgeting centers, to introduce free choice as a response to public demand, and to simulate marketing by private production of public services are elements suggested in this paper to improve public health services management.  相似文献   
993.
α-Sarcin binds one Zn(II) cation per protein molecule, with a Kd value of 0.9 mM, determined by equilibrium dialysis experiments. Ca(II), Mg(II), and Mn(II) do not bind to α-sarcin. Cd(II) and Co(II) also behave as Zn(II). The binding produces local modifications on the protein conformation affecting the microenvironment of tryptophan residues. The three cations modify the fluorescence emission of the protein. The near-u. v. circular dichroism spectrum of the protein is also altered. The binding of Zn(II) and related cations does not modify the secondary structure of the protein. The ribonucleolytic activity of a-sarcin is inhibited upon Zn(II) binding, but no alteration of the ability of the protein to aggregate phospholipid vesicles has been observed.  相似文献   
994.
An area analysis is presented of deaths in Auckland that were ostensibly avoidable, by appropriate medical intervention and treatment. Mortality data from the National Health Statistics Centre for the period 1977-85 were used in the analysis. The definition of an avoidable death was based on the International Classification of Diseases (ICD) code using established criteria. Eight percent of deaths of people under 65 years of age met the criteria. The basic spatial entity for the analysis is the census area unit and maps of Auckland are presented to show the distribution of avoidable mortality. It is found that there are significant and consistent spatial variations. Three areas with avoidable mortality that is generally higher than elsewhere are apparent: in south Auckland; to the north-west of the central urban sector centered on Grey Lynn; and in the eastern parts of the central sector from Glenn Innes to Onehunga.  相似文献   
995.
996.
The effects of intracerebral implants of 17 beta estradiol and cholesterol in five brain regions were tested on the duration of the dorsal immobility response in ovariectomized female rats. The dorsal immobility response was significantly prolonged by 4-hr implants of 17 beta estradiol in the dorsal striatum and nucleus accumbens, but not in the cortex, the globus pallidus, or the substantia nigra pars compacta. These data further support previous evidence that estradiol acts directly on the striatum to affect behavior in the rat.  相似文献   
997.
D J Harris  G O Waring  L L Burk 《Ophthalmology》1989,96(11):1597-1607
After penetrating keratoplasty in 52 eyes, keratography refraction and keratometry were used to select appropriate interrupted sutures for removal in order to reduce astigmatism. All eyes had one continuous and either 12 or 16 interrupted nylon sutures. The keratographs were examined retrospectively and separated into six groups on the basis of similar mire patterns. The removal of single sutures associated with three of these patterns reduced astigmatism by the following average amounts: symmetrical oval pattern, 0.44 diopters (D); D-shaped oval pattern, 2.07 D; and focal indentation pattern, 6.60 D. The other three patterns--mildly disrupted mires, incomplete mires, and uninterpretable mires--did not allow quantification of results. Examples of these keratographic patterns are presented and recommendations are made for their use in the management of astigmatism following penetrating keratoplasty.  相似文献   
998.
N-Hydroxythalidomide (1d), a potential metabolite of thalidomide (1a), was synthesized from N-phthalyglutaminic acid anhydride (1b) and O-tetrahydropyraline hydroxylamine, followed by deprotection. The teratogenicity of 1d was studied using the Hen's-Egg-Test model which had been found applicable for 1a. 1d was more teratogenic to chicken embryos compared to 1a. The percentage of teratogenic malformations in the 1d groups was 28-46%, whereas the percentage in the 1a groups was 20-23%. The oxygen protected precursor N-hydroxythalidomide (1c) was less teratogenic (11-15%).  相似文献   
999.
Two antifungal antibiotics maniwamycins A and B were isolated from the culture broth of a strain of actinomycetes, which were classified as Streptomyces prasinopilosus. These antibiotics were isolated by resin absorption and extraction with EtOAc and purified by column chromatography. Both antibiotics were found to be new azoxy substances from their physico-chemical properties. They showed broad antifungal spectra.  相似文献   
1000.
A series of new 4-aryl-5-[omega-(4-aryl-1-piperazinyl)alkyl]-2(3H)- oxazolones was synthesized and tested for neuroleptic activity in mice and rats. Several compounds exhibited interesting neuroleptic activity with very low liability to the extrapyramidal side effects. In particular the activity of 4-(4-fluorophenyl)-5-[2-[4-(3,5-dichlorophenyl)-1- piperazinyl]ethyl]-2(3H)-oxazolone (14) was greater than that of butropipazone and fluanisone, while of the same order of that of chlorpromazine; however, the product showed a longer lasting activity and minor ability to produce catalepsy as compared with the reference drugs.  相似文献   
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