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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
75.
Introduction: Temporary GES (tempGES) can improve both gastric emptying and symptoms in post-surgical gastroparesis (PS-GP). (SSAT 2004). Long-term effects on GI symptoms and gastric emptying are unknown. Since many PS-GP patients have non-delayed emptying, the long-term effect on baseline normal or rapid emptying is also unknown.
Patients: 36 pts (6 M, 30 F, mean age 42 years) with post-surgical: Bilroth I ( n = 11), Bilroth II ( n = 4), other gastric surgery ( n = 21) disordered gastric emptying were evaluated.
Methods: GI symptoms (vomiting = V, Total = TSS), and solid meal gastric emptying (GET) at 1 and 4 h, were compared at baseline (Base), after temporary (tempGES) and permanent (permGES) gastric electrical stimulation as previously described (NGM, 2004; 16: 635.) Long-term follow-up for permanent GES ranged from 6 month to 10 years. Results were compared by t-tests, and are reported as means ± SEM.
Results: 29 of the 36 patients were able to tolerate food for baseline quantitative gastric emptying testing. 20 patients had delayed and 9 patients had non-delayed gastric emptying, with 7/9 being rapid. With both tempGES and permGES, GI symptoms improved (p < 0.05). Both tempGES and permGES showed accelerated GET for delayed patients and generally slowed GET for non-delayed (p < 0.05 for 1 h values). See tables below.
Conclusions: In a large group of post-surgical GP patients, temporary and permanent gastrointestinal electrical stimulation improved GI symptoms independent of gastric emptying and for a prolonged time. GES improves symptoms independent of baseline gastric emptying, and improves GET dependent on the baseline gastric emptying.
Patients: 36 pts (6 M, 30 F, mean age 42 years) with post-surgical: Bilroth I ( n = 11), Bilroth II ( n = 4), other gastric surgery ( n = 21) disordered gastric emptying were evaluated.
Methods: GI symptoms (vomiting = V, Total = TSS), and solid meal gastric emptying (GET) at 1 and 4 h, were compared at baseline (Base), after temporary (tempGES) and permanent (permGES) gastric electrical stimulation as previously described (NGM, 2004; 16: 635.) Long-term follow-up for permanent GES ranged from 6 month to 10 years. Results were compared by t-tests, and are reported as means ± SEM.
Results: 29 of the 36 patients were able to tolerate food for baseline quantitative gastric emptying testing. 20 patients had delayed and 9 patients had non-delayed gastric emptying, with 7/9 being rapid. With both tempGES and permGES, GI symptoms improved (p < 0.05). Both tempGES and permGES showed accelerated GET for delayed patients and generally slowed GET for non-delayed (p < 0.05 for 1 h values). See tables below.
Conclusions: In a large group of post-surgical GP patients, temporary and permanent gastrointestinal electrical stimulation improved GI symptoms independent of gastric emptying and for a prolonged time. GES improves symptoms independent of baseline gastric emptying, and improves GET dependent on the baseline gastric emptying.
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Gestational exposure to chlorpyrifos: dose response profiles for cholinesterase and carboxylesterase activity 总被引:3,自引:2,他引:1
This study investigates the in vivo dose response profiles of the target
enzyme cholinesterase (ChE) and the detoxifying enzymes carboxylesterase
(CaE) in the fetal and maternal compartments of pregnant rats dosed with
chlorpyrifos [(O,O'-diethyl O-3,5,6-trichloro- 2-pyridyl)
phosphorothionate], a commonly used organophosphorus insecticide. Pregnant
rats were dosed daily (po) with chlorpyrifos in corn oil (0, 3, 5, 7, or 10
mg/kg) on gestational days (GD) 14-18. Animals were sacrificed 5 h after
the last chlorpyrifos dose (time of maximum brain cholinesterase
inhibition) for analysis of ChE and CaE activity in maternal blood, liver,
brain, placenta, and fetal liver and brain. The in vitro sensitivity (i.e.,
IC50, 30 min, 26 degrees C) of CaE also was determined by assaying the
activity remaining after incubation with a range of chlorpyrifos-oxon
concentrations. In vivo exposure to 10 mg/kg chlorpyrifos from GD14-18
caused overt maternal toxicity, with dose-related decreases in ChE activity
more notable in maternal brain than fetal brain. Dose-related effects were
also seen with chlorpyrifos-induced inhibition of fetal liver ChE and
maternal brain CaE activities. Gestational exposure caused no inhibition of
placental ChE or CaE, fetal brain CaE, or maternal blood CaE. ChE
activities in the maternal blood and liver, as well as fetal and maternal
liver CaE, however, were maximally inhibited by even the lowest dosage of
chlorpyrifos. The in vitro sensitivity profiles of CaE to chlorpyrifos-oxon
inhibition were valuable in predicting and verifying the in vivo CaE
response profiles. Both the in vivo and in vitro findings indicated that
fetal liver CaE inhibition was an extremely sensitive indicator of fetal
chlorpyrifos exposure.
相似文献
78.
KL Cassidy GJ Reid PJ McGrath DJ Smith TL Brown GA Finley 《Acta paediatrica (Oslo, Norway : 1992)》2001,90(11):1329-1336
The effectiveness of a eutectic mixture lidocaine-prilocaine topical anaesthetic cream (EMLA) patch compared with a placebo patch in the reduction of pain associated with intramuscular immunization was evaluated. As part of the study, 161 children (aged 4-6-y) undergoing routine diphtheria, pertussis, tetanus and polio (DPTP) immunization in five urban and five rural private office settings were randomly assigned to an EMLA patch (n = 83) or a placebo patch control group (n = 78). Pain measurements included: child's self-report on a Faces Pain Scale; facial action on the Child Facial Coding System; the Children's Hospital of Eastern Ontario Pain Scale and parent and technician ratings on a Visual Analogue Scale. Parents also rated their own and their child's immunization-related anxiety on a Visual Analogue Scale. The EMLA patch group had significantly less pain on all four pain measures compared with the placebo group. Of the children in the placebo group, 43% had clinically significant pain, compared with 17% of children in the EMLA patch group. No severe adverse symptoms occurred as a result of either EMLA or placebo patch application. CONCLUSION: The EMLA patch reduced immunization pain in 4 to 6-y-old children during needle injection. 相似文献
79.
Incidence of cervical dysplasia and cervical cancer in women living with HIV in Denmark: comparison with the general population 下载免费PDF全文
80.
In vivo and in vitro MR imaging of renal tumors: histopathologic correlation and pulse sequence optimization 总被引:1,自引:0,他引:1
Quint LE; Glazer GM; Chenevert TL; Fechner KP; Gikas PW; Shireman PK; Grossman HB; Li KC 《Radiology》1988,169(2):359-362
Magnetic resonance (MR) imaging has given mixed results in the detection of renal masses. To identify the reasons for this and to determine the optimal pulse sequences for evaluating renal tumors, the authors imaged 12 primary renal tumors in vivo and 17 in vitro at 0.35 T. Histopathologic findings for each specimen were closely correlated with the MR images. Four of seven solid tumors imaged in vivo were isointense with surrounding normal renal parenchyma at all pulse sequences. The other three tumors were hyperintense in vivo at T2-weighted sequences. At heavily T2-weighted sequences eight solid tumors were hyperintense in vitro and four were hypointense. There was no correlation between signal intensity and specific tissue type or histologic pattern for solid tumors. The five cystic tumors were well seen both in vivo and in vitro on T2-weighted images. However, the signal intensity of the cyst fluid was an unreliable indicator of benignancy. SE MR imaging at 0.35 T has significant limitations in the detection of solid renal masses. 相似文献