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1.
Pica practices of pregnant women 总被引:2,自引:0,他引:2
R D Horner C J Lackey K Kolasa K Warren 《Journal of the American Dietetic Association》1991,91(1):34-38
This report summarizes current knowledge about pica practices during pregnancy through a systematic review of the literature for the period 1950 through 1990. Pica behavior was considered in terms of its prevalence, risk factors, clinical profile, and effect on pregnancy outcome. Data on pica practices by pregnant women are limited and inconclusive but reveal several interesting relationships. The prevalence of pica among pregnant women in high-risk groups declined between the 1950s and the 1970s but now remains steady, affecting about one fifth of high-risk women. Women at high risk of pica are more likely to be black, to live in rural areas, and to have a positive childhood and family history of pica. The clinical picture of the disorder during pregnancy is not well described. The evidence suggests that pica during pregnancy results in anemia, but it is not definitive. Pica also has been associated with maternal and perinatal mortality. We conclude that the behavior is more prevalent than commonly believed, shows no sign of further decline, and may have serious effects, particularly anemia, on mother and infant. Dietetic practitioners who counsel pregnant women should ask questions about pica when they conduct nutrition assessments of their clients. 相似文献
2.
Lens complementation system for the genetic analysis of growth, differentiation, and apoptosis in vivo. 总被引:3,自引:0,他引:3
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N J Liégeois J W Horner R A DePinho 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(3):1303-1307
A genetic approach has been established that combines the advantages of blastocyst complementation with the experimental attributes of the developing lens for the functional analysis of genes governing cellular proliferation, terminal differentiation, and apoptosis. This lens complementation system (LCS) makes use of a mutant mouse strain, aphakia (ak), homozygotes of which fail to develop an ocular lens. We demonstrate that microinjection of wild-type embryonic stem (ES) cells into ak/ak blastocysts produces chimeras with normal ES-cell-derived lenses and that microinjection of Rb-/- ES cells generates an aberrant lens phenotype identical to that obtained through conventional gene targeting methodology. Our determination that a cell autonomous defect underlies the aphakia condition assures that lenses generated through LCS are necessarily ES-cell-derived. LCS provides for the rapid phenotypic analysis of loss-of-function mutations, circumvents the need for germ-line transmission of null alleles, and, most significantly, facilitates the study of essential genes whose inactivation is associated with early lethal phenotypes. 相似文献
3.
M J Hershman R I Swift D T Reilly W A Logan J M Sackier H Gompertz J Horner N W Baker C B Wood 《Journal of the Royal College of Surgeons of Edinburgh》1990,35(1):29-32
This study compared one dose of cefotetan with three doses of piperacillin as prophylaxis against wound infection in 153 patients undergoing elective colorectal surgery. The patients were randomized into two groups: the first received 2 g cefotetan intravenously with induction of anaesthesia (n = 75), and the second received three doses of 2 g piperacillin (n = 78). Wound infection was defined as the presence of an abscess or discharging pus from the wound. In the cefotetan group there were 14 (19%) wound infections and 13 (17%) in the piperacillin group. There were three septic deaths, one in the cefotetan group and two in the piperacillin group. Both groups were comparable with regard to age, sex, nature of pathology and pre- and perioperative risk factors. No significant haematological or biochemical abnormalities were detected. The only adverse reaction was one patient who had an allergic reaction (rash) to piperacillin. These data suggest that single-dose cefotetan is as effective as triple-dose piperacillin in prophylaxis against infection in elective colorectal surgery. 相似文献
4.
A polyclonal antiserum which recognizes surface epitopes on IL1-activated pig chondrocytes has been used to immunolocalize chondrocytes responding to IL1 produced during co-culture of pig synovium and articular cartilage. Activation of the chondrocytes by the cytokine was restricted to the articular and subarticular region of the cartilage adjacent to the synovium. Chondrocyte activation was also seen when human rheumatoid synovium was co-cultured with the cartilage. The presence of IL1 in some synovial cells was confirmed by immunolocalization using antisera specific for IL1 alpha and IL1 beta. 相似文献
5.
6.
T J Molloy Y Wang A Horner T M Skerry G A C Murrell 《Journal of orthopaedic research》2006,24(4):842-855
Tendon healing is a complex process consisting of a large number of intricate pathways roughly divided into the phases of inflammation, proliferation, and remodeling. Although these processes have been extensively studied at a variety of levels in recent years, there is still much that remains unknown. This study used microarray analyses to investigate the process at a genetic level in healing rat Achilles tendon at 1, 7, and 21 days postinjury, roughly representing the inflammation, proliferation, and remodeling phases. An interesting temporal expression profile was demonstrated, identifying both known and novel genes and pathways involved in the progression of tendon healing. Both inflammatory response and pro-proliferative genes were shown to be significantly upregulated from 24 h postinjury through to 21 days. Day 7 showed the largest increase in genetic activity, particularly with the expression of collagens and other extracellular matrix genes. Interestingly, there was also evidence of central nervous system-like glutamate-based signaling machinery present in tendon cells, as has recently been shown in bone. This type of signaling mechanism has not previously been shown to exist in tendon. Another novel finding from these analyses is that there appears to be several genes upregulated during healing which have exclusively or primarily been characterized as key modulators of proliferation and patterning during embryonic development. This may suggest that similar pathways are employed in wound healing as in the tightly regulated progression of growth and development in the embryo. These results could be of use in designing novel gene-based therapies to increase the efficacy and efficiency of tendon healing. 相似文献
7.
8.
E MOLKE JENSEN K. A. THIESSEN AA. CHRISTENSEN 《Acta anaesthesiologica Scandinavica》1986,30(2):109-110
The effect of 4 mg oral naloxone on preoperative gastric volume and pH of gastric aspirate was studied in a double-blind, randomized study. Twenty patients received 10 ml of naloxone (4 mg) mixed with 10 ml of orange juice, and 20 patients received 10 ml of isotonic saline mixed with 10 ml of orange juice, 2 h before surgery. Gastric content was obtained immediately after intubation of the trachea. No significant difference in gastric volume and pH of gastric aspirate was found between the two groups. It is concluded that naloxone does not affect gastric emptying and gastric acid secretion to a degree great enough to protect against aspiration of gastric contents into the lungs. 相似文献
9.
10.
The detection of cytotoxicity produced by short-lived reactive intermediates: a study with bromobenzene 总被引:1,自引:0,他引:1
S A Horner J R Fry R H Clothier M Balls 《Xenobiotica; the fate of foreign compounds in biological systems》1987,17(6):777-782
1. A V79 cell incubation incorporating rat liver 9000 g supernatant (S9) fractions, used previously to detect the toxicity due to long-lived, stable metabolites of cyclophosphamide, has been used to study the toxicity of short-lived, reactive metabolites generated from bromobenzene. 2. Cytotoxicity was observed in the presence of S9 fractions from rats treated with phenobarbitone but not in the presence of S9 fractions from untreated or beta-naphthoflavone-treated animals. This toxicity was enhanced by depletion of the glutathione in the S9 fraction by prior treatment of the animals with diethyl maleate and was reduced by SKF 525 A, in agreement with results in vivo on the mechanism of bromobenzene-induced hepatotoxicity. 3. This study demonstrates that cytotoxicity due to the generation of short-lived, reactive metabolites can be detected in this system in vitro provided that procedures are used to modify the activating and detoxifying enzyme systems within the S9 fraction. 相似文献