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排序方式: 共有440条查询结果,搜索用时 15 毫秒
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PJ Garry ; DJ VanderJagt ; SJ Wayne ; KH Koehler ; RL Rhyne ; TL Simon 《Transfusion》1991,31(8):686-692
Iron stores were observed in 57 healthy elderly volunteers, between 63 and 77 years of age, who donated 5 units of blood over approximately 1 year. An equal number of nondonors who contributed approximately 7 mL of blood at each visit for iron status measurements only were seen at the same frequency as the donor population. At entrance to the study, iron stores in women and men averaged 724 and 875 mg, respectively. After five donations, mean iron stores dropped to 67 mg in women (n = 27) and 362 mg in men (n = 30); four women (15%) became iron deficient, while two (7%) developed iron deficiency anemia. Three men (10%) developed iron deficiency, but none were found to be anemic. Mean intakes of iron were 23.3 and 22.5 mg per day, respectively, for women and men. Iron intakes were adequate to meet iron requirements of nondonors, but they were not sufficient to halt the steady decrease in iron stores among the donor population, in whom iron absorption increased from approximately 5 percent at entrance to 14 percent at the time of the fifth donation. In summary, healthy elderly persons may contribute to the national blood resource; however, donations should probably be limited to less than five per year or donors should regularly take an iron supplement to preserve reasonable amounts of iron reserves. 相似文献
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We compared the efficiency of removing cosmetic eyeliner deposits from soft contact lenses with a variety of surfactant cleaners. Four types of daily cleaners were used to clean two groups of soft contact lenses (Group 1 and Group 2 : FDA classification) contaminated with an eyeliner. The lenses were cleaned in a Clensatron 700CL Automatic Contact Lens Cleaning unit. The amount of lens contamination before and after cleaning was quantified by digitising a photograph of the lens surface. We found that: 1. the eyeliner was less likely to adhere to Group 2 lenses, 2. the efficiency of removing eyeliner was independent of the cleaning solutions we used; when contaminated, Group 2 lenses were generally easier to clean, 3. the Clensatron unit was not as efficient as digital rubbing in removing the eyeliner. 相似文献
96.
Normal human spermatozoa carry either the X or the Y chromosome. The
differences between X and Y spermatozoa (X and Y haploid cells) may exist
in two areas: the different chromosomes (i.e. different kinds and numbers
of genes) and the different sperm structures and functions (i.e. different
genetic expression). The aim of this study was to determine whether there
are any size between X and Y spermatozoa and whether sperm size and shape
varies between men. Identification of the Y (and X inferred) status of
individual spermatozoa was carried out by polymerase chain reaction (PCR),
amplifying the putative testis- determining gene (SRY) together with a
control gene (ZP3). PCR amplification of 871 out of 895 (97.3%) single
motile spermatozoa showed that 444 (51.0%) were Y and 427 (49.0%) were
X-bearing spermatozoa. Of 233 normally-shaped but immobilized spermatozoa,
217 (93.1%) were photographed and measured. Statistically, the length,
perimeter and area of the sperm heads, and the length of the sperm necks
and tails of X-bearing spermatozoa were significantly larger and longer
than those of Y-bearing spermatozoa. Some peculiarities (or variations) in
the X and Y sperm shape and size in individual donors were found. The
pre-screening by micro-measurement of these specific haploid
characteristics of individual spermatozoa in different donors, which may be
closely related to their different genetic conditions (or diseases), may be
important in human medicine and animal husbandry, especially in sperm
prefertilization diagnosis.
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Three previously healthy infants presented with diarrhoea and pyrexia and deteriorated rapidly. Two patients had necrotizing bowel disease requiring aggressive surgical intervention. All survived. P. aeruginosa gastrointestinal infection in previously healthy children is an extremely rare condition with a high mortality. Ecthyma gangrenosum was present in over 60% of reported cases although often not recognized initially. A high index of clinical suspicion, including prompt recognition of ecthyma gangrenosum, is mandatory for an early diagnosis of P. aeruginosa gastrointestinal infection. Early diagnosis and treatment may improve the prognosis. 相似文献