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排序方式: 共有372条查询结果,搜索用时 27 毫秒
81.
Papillary endolymphatic sac tumors: CT, MR imaging, and angiographic findings in 20 patients 总被引:6,自引:0,他引:6
82.
RP Jankov CF Boerkoel J Hellmann WL Sirkin Z Tumer N Horn A Feigenbaum 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(12):1297-1300
A male neonate presented with an acute onset of severe intra-abdominal bleeding, haemorrhagic shock and multiple fractures leading to death on d 27. Menkes' disease was diagnosed at autopsy and confirmed by copper accumulation studies on cultured fibroblasts. Such an early onset of fatal complications in this condition has not been previously reported. New insights into the pathogenesis of Menkes' disease provided by DNA mutation analysis and difficulties in neonatal diagnosis are discussed. Menkes' disease should be considered in male infants with pathological fractures and other signs of connective tissue disease, even in the neonatal period. 相似文献
83.
84.
CF Poets VA Stebbens JR Alexander WA Arrowsmith SAW Salfield DP Southall 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(6-7):536-541
Nineteen infants who were graduates from special care baby units underwent two overnight tape recordings of oxygen saturation (SaO2) and breathing movements; one during an upper (n = 12) or lower (n = 7) respiratory tract infection and the other when free of infection. Baseline SaO2 was lower during infection (median 99.6 vs 100%, p less than 0.01), with four patients having values (84.3-95.5%) below the normal lower limit for full-term infants (97%). The median number of apnoeic pauses was also lower during respiratory tract infection (4.7 vs 15.7/h, p less than 0.02). The median number of episodic desaturations (SaO2 less than or equal to 80%) did not change significantly (1.3 vs 1.9/h, p greater than 0.05), with the exception of one patient who had extremely increased values during infection for both apnoeic pauses (63/h) and desaturations (112/h). No infant, however, was considered clinically hypoxaemic. Clinically unsuspected hypoxaemia may thus occur during respiratory tract infection in a proportion of infants graduating from special care baby units. Such hypoxaemia may have potentially deleterious effects. 相似文献
85.
ERJ Giugliani RMS Issler EB Justo CF Seffrin RM Hartmann NM Carvalho 《Acta paediatrica (Oslo, Norway : 1992)》1992,81(6-7):484-487
A prospective study was undertaken to identify possible factors related to the duration of breast feeding. Two hundred and thirty-eight mothers who had delivered normal single babies with birth weights greater than 2.5 kg and had initiated breast feeding were randomly selected at the maternity hospital, Hospital de Clinicas de Porto Alegre, Brazil, and followed by mail questionnaires until termination of breast feeding, or until the end of the first year. If no reply was received, telephone contact or home visits were made. The group of mothers who stopped breast feeding prior to the end of the third month was compared with those who extended breast feeding beyond three months with respect to socioeconomic, biological, environmental, medical and psychological factors. The variables with a significant coefficient of association with early termination of breast feeding were maternal education, past experience with breast feeding, help of a maid, help with housework provided by a relative, breast feeding orientation during prenatal care and encouragement from the husband. These factors act simultaneously, with interactions among them. 相似文献
86.
87.
Background: The Müller cell, the major glial cell in the retina, may be important in diabetes. The purpose of this project was to examine the localisation of glutamine synthetase in control and diabetic Müller cells and to determine whether the number of Müller cells is altered during diabetes. We also examined whether two experimental treatments of diabetes, aminoguanidine and ramipril, ameliorated these changes. Methods: Normal Sprague‐Dawley rats rendered diabetic by a single injection of streptozotocin (50 mg/kg) were treated with either aminoguanidine, ramipril or standard water. Following 12 weeks, animals were sacrificed, their eyes removed and the retinae processed for glutamine synthetase immunocytochemistry. The level of glutamine synthetase was quantified in control and diabetic animals and the number of Müller cells counted for each of the treatment groups. Results: In all retinae examined, glutamine synthetase labelled Müller cells along their entire cellular extent and endfeet were more intensely labelled. Following 12 weeks of diabetes, there was a small increase in the level of glutamine synthetase labelling in somata and endfeet compared with controls (ANOVA, P < 0.05). The number of Müller cells was increased following 12 weeks of diabetes (ANOVA, P < 0.0001). This effect was ameliorated by treatment with ramipril and aminoguanidine. Conclusions: These data suggest that Müller cells are altered in number following 12 weeks of diabetes. Moreover, the two experimental treatments were beneficial in preventing this change in Müller cells. Further work is required to establish the mechanisms underlying the change to Müller cells during diabetes. 相似文献
88.
The production of leukaemia inhibitory factor by human endometrium: presence in uterine flushings and production by cells in culture 总被引:12,自引:5,他引:12
Laird SM; Tuckerman EM; Dalton CF; Dunphy BC; Li TC; Zhang X 《Human reproduction (Oxford, England)》1997,12(3):569-574
The concentration of leukaemia inhibitory factor (LIF) was measured in
uterine flushings obtained from normal fertile women, from women with
unexplained infertility and from women who suffered recurrent miscarriage.
In normal fertile women, LIF was not detected in flushings obtained on days
luteinizing hormone (LH)+0 to LH+6 of the cycle, but concentrations
gradually increased from day LH+7 to a maximum at day LH+12. The amount of
LIF in flushings obtained from women with unexplained infertility was
significantly lower than in those from normal fertile women on day LH+10 (P
< 0.05). The production of LIF by cultured human epithelial and stromal
cells was also investigated. LIF was not detectable in the supernatants of
cultured stromal cells. Basal LIF production by epithelial cells varied
according to the stage in the cycle at which the biopsy was taken.
Significantly more LIF was produced by epithelial cells from late
proliferative and early secretory endometrium compared with amounts
produced by cells from early proliferative (P < 0.001) and late
secretory (P < 0.01) endometrium. High doses of progesterone and
oestradiol caused a small decrease in epithelial cell LIF production: the
combined effect of progesterone and oestradiol (P < 0.01) was greater
than the effect of either steroid alone (P < 0.05). The results show,
for the first time, the capability of human endometrium to produce LIF in
vivo. The fact that maximum LIF concentrations are present at implantation
and that decreased concentrations occur in women with unexplained
infertility suggest the importance of this cytokine in embryo implantation.
相似文献
89.
This presentation will describe a pilot study of radio-frequency (RF) identification tags ("chips") that was conducted in parallel with standard procedures for the collection and testing of Red Blood Cells (Greater Chesapeake and Potomac Region, American Red Cross Biomedical Services, Baltimore, MD) and transfusion (Georgetown University Hospital, Washington, DC). The purpose of the study was to evaluate whether multi-write RF chips could be attached to blood bags, programmed, and used to facilitate the collection of information from (1) a blood bag manufacturer to (2) a blood collection center and, subsequently, to (3) a hospital transfusion service. 相似文献
90.