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81.

Objective

This study determined growth and stool characteristics of infants fed a formula with reduced content of a partially hydrolyzed protein of improved quality and assessed the effect of the addition of a probiotic on infant growth and health.

Design, methods

The double-blind study involved three formulas: a reduced protein (1.90 g/100 kcal) formula (formula RP), the same formula with Bifidobacterium lactis (formula RP+P), and a higher-protein (2.39 g/100 kcal) control formula (C). Protein of the formulas consisted of partially hydrolyzed modified whey proteins. Normal term infants were randomly assigned to one of the formulas, which were fed from soon after birth to 4 months of age; 88 infants completed the study. Growth was measured and formula tolerance, stool characteristics, and illness incidence were recorded.

Results

All three formulas supported growth equally well. Plasma concentrations of urea and of threonine and proline were markedly (significantly) lower with RP and RP+P than with C. No differences in feeding-related behaviors were noted, but stools were softer with formula C than with the other formulas. Infants fed RP+P had significantly fewer episodes of diarrhea (0.21 episodes) than infants fed RP (0.41 episodes) or C (0.91 episodes).

Conclusion

A reduced-protein formula with and without added probiotics (B. lactis) supports normal growth of infants during the first 4 months. In addition, it leads to lower plasma levels of urea, threonine, and proline. Supplementation of the formula with Bifidobacterium lactis offers protection against diarrheal illness.
  相似文献   
82.
83.
Insomnia predicts cardiovascular and non-cardiovascular disease mortality. This study evaluated EEG sleep, nocturnal sympathetic activity, and daytime measures of immune function in subjects with primary insomnia (n = 17) and patients with current major depression (n = 14) as compared to controls (n = 31). Insomniacs showed disordered sleep continuity along with nocturnal increases of average levels of circulating norepinephrine and decreases of natural killer cell responses, whereas depressed patients showed declines of natural killer cell activity, but no differences of EEG sleep or nocturnal catecholamines as compared to controls. Impairments of sleep efficiency correlated with nocturnal elevations of norepinephrine in the insomniacs but not in the depressives or controls. These data indicate that insomnia is associated with nocturnal sympathetic arousal and declines of natural immunity, and further support the role of sleep in the regulation of sympathetic nervous and immune system functioning.  相似文献   
84.
PURPOSE: To evaluate the relative impact of 3 and 5 min of hyperventilation (HV) and different sleep stages on the sensitivity of the interictal EEG in focal epilepsy. METHODS: We examined 20 patients with temporal lobe epilepsy (TLE, 85%) or extratemporal epilepsy during EEG-monitoring. We compared 6 min EEG (12 epochs of 30s) during/after each: (a) waking; (b) 5 or 3 min of HV; (c) sleep stages 1, 2, 3/4 and REM regarding the frequency of epileptiform discharges (ED). The Wilcoxon matched pairs signed rank test was used. The main endpoint was the comparison of 5 min of HV with sleep stage 2. RESULTS: During sleep stage 2, ED were more frequent than during/after 5 min of HV (P=0.002). Compared to the waking EEG, all NREM-sleep stages activated ED. Sleep stage 2 was associated with the strongest activation. There was no difference between the waking state and REM-sleep. Compared to the waking EEG, neither 3 nor 5 min of HV showed an activation of ED. CONCLUSION: In patients with TLE, sleep stage 2 shows a significantly higher sensitivity for ED than 5 min of HV. Compared to the waking EEG, HV showed no activating effect on ED. These results suggest that in patients with the clinical diagnosis of TLE (and possibly other focal epilepsies) measures to record sleep stage 2 (such as sleep deprivation) should be increased whereas HV appears to be dispensable in this setting.  相似文献   
85.
Aggressive nutrition of the very low birthweight infant   总被引:10,自引:0,他引:10  
We propose an approach to nutrition of the VLBW infant that aims at minimizing the interruption of nutrient uptake engendered by premature birth. Our approach is aggressive in that it goes beyond current practice in several key aspects. The gap in nutrient intakes between the proposed aggressive approach and current practice will most likely disappear over the next few years as today's aggressive practice becomes tomorrow's standard practice. As the gap diminishes, so will the threat that nutritional deprivation poses to growth and development of VLBW infants.  相似文献   
86.
It is well established that after acclimatization at high altitude, many sympathetic pathways are hyperactive yet heart rate (HR) remains unchanged. In this study, we attempted to determine if this unchanged heart rate is due to compensatory mechanisms such as changes in parasympathetic activity or levels of receptors for autonomic neurotransmitters. We also examined the role played by hypoxia in these autonomic adaptations to high altitude. Three experiments were carried out on five healthy lowlanders both at sea level (SL) and after 2 weeks of acclimatization at 3800 m (Post-Ac) with: (a) placebo (control); (b) acute beta-adrenergic receptor blockade by propranolol (PRO), or (c) acute parasympathetic receptor blockade by glycopyrrolate (GLY). Compared with SL control values, post-Ac venous norepinephrine (NE) and dopamine increased by 96% (p < 0.001) and 55% (p < 0.05), but epinephrine and HR did not change. PRO resulted in a smaller decrease in HR (bpm) Post-Ac than at SL (15 +/- 6 vs. 21 +/- 6, p < 0.05), while GLY caused a greater increase in HR Post-Ac than at SL (59 +/- 8 vs. 45 +/- 6, p < 0.05). Breathing oxygen at SL concentration while at altitude did not decrease NE, or alter the effect of PRO on HR, but reduced the chronotropic effect of GLY by 14% (p < 0.05). These results suggest that after acclimatization to altitude, increased parasympathetic neurotransmitter release and decreased beta-adenoreceptor activity account for the unchanged HR despite enhanced sympathetic activity. Acute oxygen replacement rapidly counteracted the parasympathetic, but not sympathetic hyperactivity that occurs at high altitude.  相似文献   
87.
88.
OBJECTIVE: To determine if controlled preparation of the endometrium with exogenous estradiol (E2) and progesterone (P) could be achieved in women retaining their ovarian function without requiring prior ovarian suppression with a long-acting agonist of gonadotropin-releasing hormone (GnRH-a). DESIGN: Prospective feasibility study of a new simplified hormone regimen for preparation of endometrium receptivity. Six volunteer women received transdermal E2 and vaginal P without prior suppression of their ovarian function with GnRH-a. The control group consisted of previously reported cases receiving GnRH-a and E2 and P. SETTING: Academic tertiary care institution. PATIENTS: Six volunteer women. MAIN OUTCOME MEASURES: Participants received transdermal E2 and P after a regimen designed to duplicate the plasma E2 and P levels seen in the menstrual cycle. INTERVENTION: Endometrial biopsy. RESULTS: Plasma luteinizing hormone increased to surge levels in one woman on day 11, in two on day 12, and on day 14 in the remaining three women. No follicular growth was noticed on ultrasound, and no increase in plasma P occurred before the onset of P administration on day 15. Day 20 endometrium specimens showed early secretory changes as previously reported in women deprived of ovarian function receiving similar hormonal treatment. CONCLUSIONS: Our results indicate that controlled preparation of the endometrium can be achieved with exogenous E2 and P without prior ovarian suppression with a GnRH-a in women having functioning ovaries. Hence, administration of exogenous E2 and P appears to be a viable simpler alternative to the combined administration of GnRH-a and exogenous E2 and P, which avoids the side effects and the cost of GnRH-a.  相似文献   
89.
Circulating DNA: a new diagnostic gold mine?   总被引:9,自引:0,他引:9  
The recent discovery that cell-free DNA can be shed into the bloodstream as a result of tumour cell death has generated great interest. Numerous studies have demonstrated tumour-specific alterations in DNA recovered from plasma or serum of patients with various malignancies, a finding that has potential for molecular diagnosis and prognosis. The implication is that tumour-derived nucleic acids of human or viral origin can be retrieved from blood by a minimally invasive procedure, and used as a surrogate tumour marker to monitor the course of the disease or aid in early diagnosis. The present review will describe the main areas of ongoing investigation, with particular emphasis on technical issues and available data of clinical relevance.  相似文献   
90.
Early diagnosis is a tenet in oncology and should enable early treatment with the expectation of improved outcome. Extent and determinants of patient delay of diagnosis in breast cancer patients and its impact on stage of disease were examined in a population based study among female breast cancer patients in Germany. Two hundred and eighty-seven women, aged 18 to 80 years with newly diagnosed invasive symptomatic breast cancer, were interviewed with respect to the diagnostic process. Patient delay was defined as time from onset of first symptoms to first consultation of a doctor. Median patient delay was 16 days among symptomatic patients. Eighteen per cent of all breast cancer patients waited longer than 3 months before consulting a physician. Long patient delay was associated with old age, history of a benign mastopathy, obesity, and indices of health behaviour such as not knowing a gynaecologist for out-patient care and non-participation in general health screening examinations. A strong association between patient delay and stage at diagnosis was observed for poorly differentiated tumours. These results suggest that at risk groups for delaying consultation can be identified and that a substantial proportion of late stage diagnoses of poorly differentiated breast cancer cases could be avoided if all patients with breast cancer symptoms would present to a doctor within 1 month.  相似文献   
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