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排序方式: 共有494条查询结果,搜索用时 31 毫秒
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74.
胰岛素样生长因子与胎儿宫内发育迟缓 总被引:1,自引:0,他引:1
0 引言 胎儿宫内发育迟缓(IUGR)是指出生体质量小于其孕龄平均体质量的第10百分位者,或者小于其平均体质量的两个标准差者.发病率约为3%~4%.IUGR是围产儿死亡的重要原因之一,新生儿期及远期发病率明显增高.在儿童期比正常儿体格和智力发育均落后.还有研究提示IUGR和成年期发生糖尿病及心血管病有因果联系[1].鉴于以上原因,IUGR的病因探讨越来越受到人们的重视,尤其是对IUGR内分泌方面的研究也越来越深入.本文着重综述近年来胰岛素样生长因子(insulinlikegrowthfact… 相似文献
75.
Schulberg HC Mulsant B Schulz R Rollman BL Houck PR Reynolds CF 《International journal of psychiatry in medicine》1998,28(4):421-436
OBJECTIVE: Identify the morbidity patterns displayed by older primary care patients experiencing depressive symptomatology who do and do not meet criteria for a major depression. METHOD: Patients ages sixty and older presenting at two ambulatory internal medicine centers were administered the CES-D. Among those scoring > or = 11, 104 completed a comprehensive assessment of their psychiatric symptomatology, medical illness, and functional abilities. The assessment battery was again administered six months later. RESULTS: The point prevalence of major depression in older primary care patients is estimated at 9 percent based on SCID interviews. Patients meeting criteria for this diagnosis compared to those who are symptomatic but not experiencing a major depression described more extensive psychopathology but also significantly more limitations in performing social and functional roles. At six-month follow-up, only 11.5 percent of those initially diagnosed with a major depression were considered fully recovered. CONCLUSIONS: Major depression is a prevalent disorder in older primary care patients which affects their ability to perform expected social and physical roles. Mechanisms for delivering efficacious treatments in routine medical practice are of a high priority. 相似文献
76.
Hydrogen peroxide inhibits gap junctional intercellular communication in glutathione sufficient but not glutathione deficient cells 总被引:7,自引:5,他引:7
Cell to cell communication via gap junctions is essential in the
maintenance of the homeostatic balance of multicellular organisms. Aberrant
intercellular gap junctional communication (GJIC) has been implicated in
tumor promotion, neuropathy and teratogenesis. Oxidative stress has also
been implicated in similar pathologies such as cancer. We report a
potential link between oxidative stress and GJIC. Hydrogen peroxide, a
known tumor promoter, inhibited GJIC in WB-F344 rat liver epithelial cells
with an I50 value of 200 microM. Inhibition of GJIC by H2O2 was reversible
as indicated by the complete recovery of GJIC with the removal of H2O2 via
a change of fresh media. Free radical scavengers, such as t-butyl alcohol,
propylgallate, and Trolox, did not prevent the inhibition of GJIC by H2O2,
which indicated that the effects of H2O2 on GJIC was probably not a
consequence of aqueous free radical damage. The depletion of intracellular
GSH reversed the inhibitory effect of H2O2 on GJIC. The treatment of
glutathione- sufficient cells with H2O2 resulted in the
hyperphosphorylation of connexin43, which is the basic subunit of the
hexameric gap junction protein, as determined by Western blot analysis.
TPA, a well-known tumor promoter, also inhibits GJIC via
hyperphosphorylation of GJIC, which is a result of protein kinase-C
activation. However, H2O2 also induced hyperphosphorylation in
GSH-deficient cells that had normal rates of GJIC. Therefore, the mechanism
of GJIC inhibition must be different from the TPA-pathway and involves GSH.
相似文献
77.
J Rigo BL Salle E Cavero P Richard G Putet J Senterre 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(2):127-131
The aim of the study was to compare growth parameters, biochemical indices of protein metabolism and plasma amino acid concentrations in infants fed either human milk ( n = 12) or a whey protein hydrolysate formula ( n = 13) during the first month of life. Growth and gain in skin fold thickness were similar in both groups whereas serum protein concentration was significantly decreased (57.4 ± 3.9 versus 61.2 ± 2.9 g/l) in the infants fed the whey hydrolysate formula. The discrepancies between the plasma amino acid pattern of the whey hydrolysate formula group and that of the human milk group lessened during the first month. Nevertheless, at a mean age of 33 days the plasma threonine concentration remained twice as high and the plasma tyrosine, phenylalanine and proline concentrations were Significantly lower in the whey hydrolysate formula group than in the human milk group. Thus, compared with breast-fed infants, growth and most of the biological indices of protein metabolism were satisfactory in infants fed during the first month of life on a whey protein hydrolysate formula. Nevertheless, the decrease in total plasma protein concentration needs to be confirmed in a larger cohort of infants. In addition, further research is necessary to investigate the possible ways of reducing the hyperthreoninemia and preventing other plasma amino acid disturbances since it would be desirable to obtain plasma amino acid levels similar to those of breast-fed infants. 相似文献
78.
AA Lapillonne FH Glorieux BL Salle PM Braillon M Chambon J Rigo G Putet J Senterre 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S405):117-122
Fat and mineral metabolic balance studies were performed in 25 normal very low-birth-weight infants ( 1500 g at birth) fed either pooled pasteurized human milk supplemented with calcium, phosphorus and magnesium, or a preterm formula. Calcium, phosphorus and magnesium intake were similar in both groups and averaged 100mg/kg/day, 72 mg/kg/day and 8 mg/kg/day, respectively. Calcium and phosphorus retention was higher in the subjects fed fortified human milk than in those receiving a preterm formula (65±14 and 62±9mg/kg/day versus 55±12 and 47±7mg/kg/day respectively). The difference was only significant for phosphorus. Magnesium retention was similar in the two groups and averaged 3 mg/kg/day. Fat intake and absorption was significantly higher in the preterm formula fed group than in the one fed fortified human milk (5.5±0.4 g/kg/day and 88±4% versus 4.2±1 g/kg/day, 79±6% respectively). Assessment of the whole body bone mineral content by dual energy X-ray absorptiometry was performed at 3 and 6 months of age in another group of 25 low-birth-weight infants fed either fortified human milk or a preterm formula. Whole body bone mineral content (BMCt) was low (43.3±30.8 g of hydroxyapatite) at 3 months of age (theoretical term) compared to normal full-term newborns at birth. There was no significant influence of the diet. At 6 months of age, BMCt reached 168.6±36.6g, a value similar to that of full-term newborns, with no significant difference between the two regimen groups. The deficit in the 12 subjects who had a BMCt under 30 g at 3 months of age had been corrected at age 6 months. Premature babies fed a pooled pasteurized human milk enriched with calcium, phosphorus and magnesium favored a better retention of calcium and phosphorus. However, no significant influence of the two diets studied was observed on the gain in BMCt over the first 6 months of life. 相似文献
79.
Red blood cell fatty acid composition in low-birth-weight infants fed either human milk or formula during the first months of life 总被引:10,自引:0,他引:10
V Chirouze A Lapillonne G Putet BL Salle 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S405):70-77
The fatty acid composition of red blood cell (RBC) phospholipids in low-birth-weight infants was determined immediately after delivery and during the first 3 months of life. In the first study, infants were fed either human milk or two formulas with different fatty acid compositions but no long chain polyunsaturated fatty acids (LCPUFA). Both groups of formula-fed infants had significantly lower levels of docosahexaenoic acid (DHA) in RBC phospholipids compared with breast-fed infants. RBC phospholipid DHA was similar in the two formula groups at all ages. In the second study, infants received either a non-supplemented or a LCPUFA-supplemented formula. DHA remained stable in RBC phospholipids of infants supplemented with LCPUFA, whereas DHA decreased in RBC phospholipids of unsupplemented infants. These results confirm that adding DHA to formulas is more effective than increasing 18:3 n-3 content, in maintaining RBC phospholipid DHA levels. 相似文献
80.
S Sampath BL Somani YV Sharma MM Arora VN Arabade 《Medical Journal Armed Forces India》2002,58(4):315-318
Ornithine carbamoyl transferase (OCT) activity and other liver function tests were studied in a total of 50 patients of clinical malaria and 15 controls. They were grouped as group I (positive for malarial parasite on peripheral blood smear, n=18), group II (negative for malarial parasite on peripheral blood smear (PBS) but responded to antimalarials, n=17) and group III (peripheral blood smear negative and did not respond to antimalarial therapy, n=15). The mean OCT levels were significantly raised in group I (6.79 ± 1.84 IU/L, p value = 0.006) and group II (5.0 ± 1.15 IU/L, p value = 0.014) as compared to controls (2.5 ± 1.13 IU/L) and returned to normal after treatment In contrast, group III had normal levels except in a case of kala azar and septicemia where OCT levels were high and increased further on treatment. Taking PBS positivity as a gold standard of diagnostic criteria, OCT had a sensitivity of 83% and specificity of 86% with a high positive predictive value of 88% as compared to ALT which had a lower sensitivity of 55% and specificity of 80%. The clinical response rate in PBS negative cases of fever having high OCT level was 83% as compared to 35% in cases with normal OCT level, making OCT a good surrogate marker of malaria. OCT levels could also be of prognostic significance as 2 cases of cerebral malaria had high OCT levels of 11.1 UAL and 10.7 IU/L, respectively.Key Words: Malaria, Ornithine carbamoyl transferase 相似文献