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排序方式: 共有3966条查询结果,搜索用时 15 毫秒
71.
JE McMICHAEL 《Journal of paediatrics and child health》1997,33(1):1-3
An understanding of the neurodevelopmental outcome of long-term survivors of neonatal intensive care is essential for the informed management of preterm or high risk infants. This annotation looks at the current status of neonatal follow-up services in Australasia and highlights problems in the collection and interpretation of data. It suggests that we should work towards achieving a consensus on standard definitions and test regimes and on national data collection. 相似文献
72.
L Patel PE Clayton ME Jenney JE Ferguson TJ David 《Archives of disease in childhood》1997,76(6):505-508
Cross sectional studies have reported impaired growth in children with atopic dermatitis. If this growth impairment is irreversible, it would be expected to adversely influence final height attainment. The standing heights and other anthropometric parameters were assessed in 35 adults with onset of atopic dermatitis before 5 years of age and a control group of 35 adults with adult onset contact dermatitis or psoriasis. There was no significant difference in the standing height SD score, mid-parental height SD score, sitting height SD score, subischial leg length SD score, nor body mass index between the atopic dermatitis and control groups. The standing height SD score was not significantly different among: (a) patients with atopic dermatitis affecting less than 50% of their body surface area and those with greater than 50% affected; (b) patients using the four different potency topical corticosteroids; and (c) patients with atopic dermatitis without asthma and those with coexisting asthma. It is concluded that short stature is not a feature of our group of adult patients with onset of atopic dermatitis before 5 years of age, continuing into adulthood, and severe enough to require specialist care. This suggests that if growth impairment occurs in childhood, it is likely to be temporary and reversible. 相似文献
73.
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
74.
Dietary polyamines promote the growth of azoxymethane-induced aberrant crypt foci in rat colon 总被引:1,自引:1,他引:1
We have examined whether dietary polyamines influence the formation and
initial growth of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in
rat colon. Effects of a combination of dietary polyamines at three dose
levels (putrescine: 50, 280, 740 nmol/g; spermidine: 10, 261, 763 nmol/g;
spermine: 1, 31, 91 nmol/g) in the polyamine-poor AIN-76A diet were studied
in animals in two different experimental situations: animals treated with
AOM alone and animals treated with AOM + difluoromethylornithine (DFMO), a
specific inhibitor of endogenous polyamine synthesis. In both experimental
situations, dietary polyamines enhanced the growth of ACF, expressed as the
number of large ACF (foci with three or more aberrant crypts, ACF > or =
3), whereas the formation of ACF, expressed as the number of ACF, was
apparently not altered. In animals treated with AOM alone, maximal growth
enhancing effect on ACF was nearly obtained with the median level of
dietary polyamine. In rats fed a low polyamine diet, basic AIN-76A, DFMO
reduced the growth of AOM-induced ACF by 83%. This inhibitory effect of
DFMO was counteracted by dietary polyamines in a dose- dependent manner,
and it was abolished at the highest level of polyamines. In conclusion, it
was demonstrated that dietary polyamines are able to enhance the growth of
AOM-induced ACF. Further, dietary polyamines reversed the DFMO-caused
inhibition of ACF growth, probably by compensating for the DFMO-reduced
endogenous polyamine synthesis.
相似文献
75.
Donnelly B 《JAMA》2000,284(16):2053-4; author reply 2054-5
76.
Hansen LA; Malarkey DE; Wilkinson JE; Rosenberg M; Woychik RE; Tennant RW 《Carcinogenesis》1998,19(10):1837-1845
We previously reported that papillomas can arise from the follicular
epithelium of v-Ha-ras transgenic TGxAC mice. Since the viable-yellow
mutation (A(vy)) of the mouse agouti gene which regulates coat color
pigmentation by acting within the micro-environment of the hair follicle
has been shown to function as a tumor promoter in the liver, we
hypothesized that it may also play a role in TGxAC skin tumorigenesis.
Endogenous agouti protein product was detected in the outer root sheath of
anagen hair follicles following plucking of the hair shaft, but not in the
interfollicular epithelium, in TGxAC mice on an FVB/N genetic background.
It was also detected in papillomas from these mice produced by
12-O-tetradecanoylphorbol-13-acetate (TPA) treatment or plucking.
Expression of the A(vy) allele in the v-Ha-ras transgenic TGxAC mouse line
results in an approximately 2-fold increase in papilloma development
compared with controls which did not carry the A(vy) allele following
twice-weekly treatment with 1.25, 2.5 or 5.0 microg TPA. In addition,
TPA-treated, papilloma-bearing F1 mice which carried the A(vy) allele, but
not F1 mice which did not carry the A(vy) allele, exhibited a syndrome of
humoral hypercalcemia mediated by parathyroid hormone-related protein
(PTHrP) that led to weight loss, hypercalcemia and hypophosphatemia. Thus,
we conclude that the A(vy) allele can influence the development of skin
tumors and PTHrP-mediated humoral hypercalcemia in v-Ha-ras transgenic
TGxAC mice.
相似文献
77.
David A. Dorr Adam Wilcox Steven M. Donnelly Laurie Burns Paul D. Clayton 《Health services research》2005,40(5P1):1400-1421
Objective. To determine how the addition of generalist care managers and collaborative information technology to an ambulatory team affects the care of patients with diabetes.
Study Setting. Multiple ambulatory clinics within Intermountain Health Care (IHC), a large integrated delivery network.
Study Design. A retrospective cohort study comparing diabetic patients treated by generalist care managers with matched controls was completed. Exposure patients had one or more contacts with a care manager; controls were matched on utilization, demographics, testing, and baseline glucose control. Using role-specific information technology to support their efforts, care managers assessed patients' readiness for change, followed guidelines, and educated and motivated patients.
Data Collection. Patient data collected as part of an electronic patient record were combined with care manager-created databases to assess timely testing of glycosylated hemoglobin (HbA1c) and low-density lipoprotein (LDL) levels and changes in LDL and HbA1c levels.
Principal Findings. In a multivariable model, the odds of being overdue for testing for HbA1c decreased by 21 percent in the exposure group ( n =1,185) versus the control group ( n =4,740). The odds of being tested when overdue for HbA1c or LDL increased by 49 and 26 percent, respectively, and the odds of HbA1c <7.0 percent also increased by 19 percent in the exposure group. The average HbA1c levels decreased more in the exposure group than in the controls. The effect on LDL was not significant.
Conclusions. Generalist care managers using computer-supported diabetes management helped increase adherence to guidelines for testing and control of HbA1c levels, leading to improved health status of patients with diabetes. 相似文献
Study Setting. Multiple ambulatory clinics within Intermountain Health Care (IHC), a large integrated delivery network.
Study Design. A retrospective cohort study comparing diabetic patients treated by generalist care managers with matched controls was completed. Exposure patients had one or more contacts with a care manager; controls were matched on utilization, demographics, testing, and baseline glucose control. Using role-specific information technology to support their efforts, care managers assessed patients' readiness for change, followed guidelines, and educated and motivated patients.
Data Collection. Patient data collected as part of an electronic patient record were combined with care manager-created databases to assess timely testing of glycosylated hemoglobin (HbA1c) and low-density lipoprotein (LDL) levels and changes in LDL and HbA1c levels.
Principal Findings. In a multivariable model, the odds of being overdue for testing for HbA1c decreased by 21 percent in the exposure group ( n =1,185) versus the control group ( n =4,740). The odds of being tested when overdue for HbA1c or LDL increased by 49 and 26 percent, respectively, and the odds of HbA1c <7.0 percent also increased by 19 percent in the exposure group. The average HbA1c levels decreased more in the exposure group than in the controls. The effect on LDL was not significant.
Conclusions. Generalist care managers using computer-supported diabetes management helped increase adherence to guidelines for testing and control of HbA1c levels, leading to improved health status of patients with diabetes. 相似文献
78.
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