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901.
BACKGROUND: A high percentage of current hospital visits are made by the elderly. The aim of this work is to quantify the risk of contracting a nosocomial infection among elderly patients admitted to a university hospital. METHODS: From the patients admitted from the emergency unit, outpatients and the waiting list, 6 patients of different age groups were chosen each day by a simple random sampling. The criteria of nosocomial infection were those of the CDC. The analysis of the information was made with the programme EPIINFO version 5. The chi 2 tests and Fisher's exact test were used to compare proportions. RESULTS: The rate of nosocomial infection in the group aged over 64 was 14.8%, showing statistically significant differences with respect to other age groups (p = 0.001). In this group the predominant infection was urinary, with an odds-ratio of 3.69, in comparison with the 25 to 44 age group. A prolonged hospital stay (> 15 days) has proved to be closely related to the risk of nosocomial infection in all age groups (p < 0.0001) in patients over 64. CONCLUSIONS: The greater risk of contracting nosocomial infections in the elderly makes it advisable to develop specific prevention programmes for this group, and the fitness of accommodations the length of stay to the care needs suitable to the hospital level.  相似文献   
902.
The actions of human synthetic gastrin I(G), the C-terminal tetrapeptide of gastrin (T), and the C-terminal octapeptide of cholecystokinin (OP) on acid secretion and transepithelial potential difference (PD) of the isolated Necturus gastric mucosa were determined. All three peptides induced H+ secretion, but the maximum H+ output was less with OP than with G or T. G and OP produced their maximum H+ output at lower molar concentrations than T. G- and OP-stimulated secretion was long sustained, but T-stimulated secretion rapidly returned to basal levels. T- and G-stimulated secretion was partially inhibited by the addition of OP. Evidence is presented that T rapidly disappears from solutions exposed to gastric mucosa, whereas G does not. Washing sensitized the mucosa to subsequent addition of T. The results suggest that the action of the common C-terminal tetrapeptide of G, T, and OP is modified by the preceding amino acid sequences, and that T, the smallest of the three peptides, is rapidly degraded by gastric tissue in vitro. The implications of the work for the study of gastrointestinal hormone structure-function relationships in isolated tissue preparations are discussed.  相似文献   
903.
904.
The incidence of pregnancy complicated by melanoma of the skin, calculated from data of the Netherlands Cancer Registry, is 1 per 10,000 pregnancies. The prognosis of a melanoma is not affected by prior or subsequent pregnancy. A melanoma diagnosed during pregnancy does appear to have a more unfavourable prognosis, due not to a less favourable clinical course, but to a delay in diagnosing melanoma during pregnancy and (or) a less favourable site. When a pregnancy is complicated by malignancy, in case of a melanoma there is a higher risk of placental metastasis compared with other malignancies. In nearly 50% of the cases reported in literature of placental metastasis there was foetal involvement.  相似文献   
905.
906.
907.
Cooling the tips of micropipettes pulled from filament-containing capillary glass dramatically increases the rate and completeness of filling with a variety of electrolyte solutions. In tests with solutions containing horseradish peroxidase this method increased the completeness of filling by more than two orders of magnitude.  相似文献   
908.
The in situ microbiota from several aquaculture facilities with active nitrification was examined by transmission electron microscopy of thin sections for the presence of bacteria that contained intracytoplasmic membranes characteristic of the nitrifying bacteria. Colonies of bacteria with the cellular morphology of a species of Nitrosomonas were found to be present in both the culture water and in the biological filter slime of a freshwater chinook salmon (Oncorhynchus tshawytscha) culture system. bacteria in the water possessed the normal nitrosomonas type of ultrastructure, whereas similar bacteria in the slime had an aberrant morphology due to multiple invaginations of the cell wall and cyto-membranes and a significantly greater number of ribosomes. These nitrosomonas-like bacteria lysed during enrichment in commonly used media. Bacteria with the morphology of species of Nitrosomonas and Nitrosococcus were also observed in colonies in the surface slimes of marine culture systems for striped bass (Morone saxatilis) and quahaug (Mercenaria mercenaria).  相似文献   
909.
910.
It is well-known that in the chick, dietary protein increases the levels of several hepatic enzymes that are involved in nitrogen metabolism and excretion. However, the biochemical mechanism of this response is essentially unknown. The experiments presented in this paper show that the chick is responding to alpha-amino nitrogen and not to any specific amino acid. Furthermore, it is shown that this system responds to endogenous sources of nitrogen as well as dietary protein and that the xanthine dehydrogenase response involves regulation of enzyme synthesis without changing the rate of degradation.  相似文献   
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