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1.
Hexavalent chromium (Cr(VI)) contamination of soil and groundwater is a major environmental concern for some industrial sites and most of the U.S. Department of Energy sites. Cr(VI) is toxic and fairly mobile in groundwater. Bioreduction of Cr(VI) to less toxic and less mobile Cr(III) is considered to be a feasible option. Among the Cr(VI) reducing bacteria, Shewanella oneidensis MR-1 (MR-1) has been shown to be effective in metal reduction under anaerobic conditions. Data on bioreduction of Cr(VI) by MR-1 in a flow-through soil column that better approximates the subsurface condition are not available. The objective of this research project was to study the bioreduction of Cr(VI) by MR-1 in a continuous-flow quartz sand column system. MR-1 was found to be very effective in reducing Cr(VI) to Cr(III) for concentrations ranging from 0.055 mM (2.85?mg/L) to 0.006 mM (0.31?mg/L). The amount of Cr(VI) reduced prior to its breakthrough was found to be inversely proportional to its concentration in the feed due to increased inhibition of microbial activity and a residual reduction of 20–45% of Cr(VI) was observed even after its breakthrough.  相似文献   

2.
Seven experiments show that an event onset shift (EOS) in an auditory sequence causes an involuntary phase correction response (PCR) in synchronized finger tapping. This PCR is (a) equally large in inphase and antiphase tapping; (b) reduced but still present when the EOS occurs in either of two interleaved (target- distractor) sequences; (c) unaffected by increased pitch separation between these sequences; (d) asymptotic in magnitude as EOS magnitude increases, unlike the intentional PCR to expected phase shifts; and (e) enhanced when the EOS precedes the onset of tapping, because of phase resetting. Thus, phase correction is revealed to be partially automatic and partially under voluntary control, and to be based mainly on temporal information derived from simple onset detection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

3.
We investigated whether nitric oxide (NO) exerts an inhibition on its own synthesis in the gastric myenteric plexus in rats. Nonadrenergic, noncholinergic relaxations in response to transmural electrical stimulation (TS) were markedly antagonized by NG-nitro-L-arginine methyl ester, (10(-4) M) and abolished by tetrodotoxin (10(-6) M). Pretreatment with various NO donors (3-morpholino-sydnonymide [SIN-1 (3 x 10(-7) to 3 x 10(-6) M)], S-nitroso-N-acetylpenicillamine (10(-6) to 10(-5) M), sodium nitroprusside (10(-8) to 3 x 10(-8) M) and 8-bromoquanosine 3', 5'-cyclic monophosphate [8-bromo-cGMP (10(-6) to 3 x 10(-6) M)]) significantly inhibited TS-evoked nonadrenergic, noncholinergic relaxations in a dose-dependent manner. In contrast, vasoactive intestinal polypeptide (10(-8) M)-induced relaxations were not affected by SIN-1 or 8-bromo-cGMP. TS evoked a significant increase in 3H-citrulline formation, which was completely abolished by calcium-free medium, NG-nitro-L-arginine methyl ester, (10(-4) M) and tetrodotoxin (10(-6) M). 3H-citrulline formation evoked by TS was significantly inhibited by SIN-1 (10(-7) to 10(-5) M) and 8-bromo-cGMP (10(-7) to 10(-5) M) in a dose-dependent manner. The inhibitory effect of SIN-1 was partially prevented by 1H-[1,2, 4]oxadiazolo[3,4-a]quinoxalin-1-one (10(-5) M), a guanylate cyclase inhibitor. We conclude that NO synthesis in the gastric myenteric plexus is negatively regulated by NO and cGMP. This suggests an autoregulatory feedback mechanism of NO synthesis in the gastric myenteric plexus.  相似文献   

4.
Different issues raised in the commentaries are elaborated in this reply. The focus was on the following five topics: (a) the nature of storage deficits in the patient groups and the different meanings that can be attached to it, (b) the possible explanations for the disordered responses of the patients, (c) suggestions for the use of other techniques to study semantic deficits, (d) the Warrington and Shallice criteria to distinguish between access and storage problems, and (e) some technical (statistical) issues raised in the commentaries. The reply concludes by highlighting the key findings reported in the target article that seem to be accepted by the large majority of the commentators. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

5.
Symptoms (of hospitalized patients) characterized as (a) self-directed, (b) directed against others, or (c) avoidance of others were related to measures of premorbid social effectiveness. More effective social adjustment was related to (a), which tended also to characterize symptoms of females. (c) was most consistently found in schizophrenics and was related to better premorbid adjustment than (b), which was most consistently found in character disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

6.
The biological reduction of uranium from soluble U(VI) to insoluble U(IV) has shown potential to prevent uranium migration in groundwater. To gain insight into the extent of uranium reduction that can occur during biostimulation and to what degree U(IV) reoxidation will occur under field relevant conditions after biostimulation is terminated, X-ray absorption near edge structure (XANES) spectroscopy was used to monitor: (1) uranium speciation in situ in a flowing column while active reduction was occurring; and (2) in situ postbiostimulation uranium stability and speciation when exposed to incoming oxic water. Results show that after 70 days of bioreduction in a high (30?mM) bicarbonate solution, the majority (>90%) of the uranium in the column was immobilized as U(IV). After acetate addition was terminated and oxic water entered the column, in situ real-time XANES analysis showed that U(IV) reoxidation to U(VI) (and subsequent remobilization) occurred rapidly (on the order of minutes) within the reach of the oxygen front and the spatial and temporal XANES spectra captured during reoxidation allowed for real-time uranium reoxidation rates to be calculated.  相似文献   

7.
Metacognitive awareness is a cognitive set in which negative thoughts/feelings are experienced as mental events, rather than as the self. The authors hypothesized that (1) reduced metacognitive awareness would be associated with vulnerability to depression and (2) cognitive therapy (CT) and mindfulness-based CT (MBCT) would reduce depressive relapse by increasing metacognitive awareness. They found (1) accessibility of metacognitive sets to depressive cues was less in a vulnerable group (residually depressed patients) than in nondepressed controls; (2) accessibility of metacognitive sets predicted relapse in residually depressed patients; (3) where CT reduced relapse in residually depressed patients, it increased accessibility of metacognitive sets; and (4) where MBCT reduced relapse in recovered depressed patients, it increased accessibility of metacognitive sets. CT and MBCT may reduce relapse by changing relationships to negative thoughts rather than by changing belief in thought content. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

8.
This article details before, during, and after "snapshots" of what it is like to go into a disaster to provide emergency mental health as part of the nation's emerging Medical Reserve Corps. It is a first-time responder's personal account of "lessons learned" and "priorities" for psychologists in similar situations. Twelve recommendations for improving psychologists' effectiveness in addressing widespread mental health disasters are identified. These include (a) team deployment and mission, (b) anticipation of frustrations, (c) prioritization in a disaster, (d) ethical dilemmas, (e) recognition of the benefits, (f) development of rapid screening tools to identify those in greatest need of mental health intervention, (g) training allied health professionals in mental health response, (h) mental health interventions specific to Katrina, (i) the importance of supporting caregivers and systems, (j) identifying and activating one's own support system, (k) slowing down interventions, and (l) training. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

9.
Niobium and tantalum are found together in natural minerals. Leaching with concentrated acid solution or alkaline roasting followed by water/dilute acid leaching results in a solution containing these two metals. In this work, we reviewed the extraction and separation of Nb(V) and Ta(V) from leach liquors in the absence and presence of hydrofluoric acid by acidic, neutral extractants and amines. Several solvent extraction systems were compared in the light of the requirement of hazardous chemicals, extraction/separation efficiency, and stability/solubility of extractants. Since the cationic species of Nb(V) and Ta(V) are unstable in the aqueous solution, the application of acidic extractants for extraction and separation of these metals is limited. Amines can extract Nb(V) as well as Ta(V) irrespective of the presence of fluoride ion but the separation of these metals from the loaded amines should be carried out in stripping process, resulting in process complexity. Another disadvantage encountered for amine is related to high viscosity in extraction process. Neutral extractants are considered as promising extractants which are effective to separate Ta(V) and Nb(V) from either non-fluoride or to moderate fluoride ion concentration in terms of extraction, separation and stripping efficiency. Compared to the traditional methyl iso-butyl ketone (MIBK) based system, methyl isoamyl ketone (MIAK) is found to be a promising extractant to separate Nb(V) and Ta(V).  相似文献   

10.
A group of eczema patients topically treated with coal tar (CT) ointments was used as a model population to examine the applicability of DNA adducts in WBC subpopulations as a measure of dermal exposure to polycyclic aromatic hydrocarbons (PAHs). Aromatic DNA adducts were examined by 32P-postlabeling in exposed skin and WBC subsets, and urinary excretion of PAH metabolites was determined to assess the whole-body burden. The median urinary excretion of 1-hydroxypyrene and 3-hydroxybenzo(a)pyrene was 0.39 (range, 0.12-1.57 micromol/mol creatinine) and 0.01 micromol/mol creatinine (range, <0.01-0.04 micromol/mol creatinine), respectively, before the dermal application of CT ointments. After treatment for 1 week, these levels increased to 139.7 (range, 26.0-510.5 micromol/mol creatinine) and 1.18 micromol/mol creatinine (range, <0.01-2.14 micromol/mol creatinine), respectively, indicating that considerable amounts of PAHs were absorbed. Median aromatic DNA adduct levels were significantly increased in skin from 2.9 adducts/10(8) nucleotides (nt; range, 0.7-10.0 adducts/10(8) nt) before treatment to 63.3 adducts/10(8) nt (range, 10.9-276.2 adducts/10(8) nt) after treatment with CT, in monocytes from 0.28 (range, 0.25-0.81 adducts/10(8) nt) to 0.86 adducts/10(8) nt (range, 0.56-1.90 adducts/10(8) nt), in lymphocytes from 0.33 (range, 0.25-0.89 adducts/10(8) nt) to 0.89 adducts/10(8) nt (range, 0.25-3.01 adducts/10(8) nt), and in granulocytes from 0.28 (range, 0.25-0.67 adducts/10(8) nt) to 0.54 adducts/10(8) nt (range, 0.25-1.58 adducts/10(8) nt). A week after stopping the CT treatment, the DNA adduct levels in monocytes and granulocytes were reduced to 0.38 (range, 0.25-0.71 adducts/10(8) nt) and 0.38 adducts/10(8) nt (range, 0.25-1.01 adducts/10(8) nt), respectively, whereas the adduct levels in lymphocytes remained enhanced [1.59 adducts/10(8) nt (range, 0.25-2.40 adducts/10(8) nt)]. Although the adduct profiles in skin and WBC subsets were not identical, and the adduct levels in WBCs were significantly lower as compared with those in skin, the total DNA adduct levels in skin correlated significantly with the adduct levels in monocytes and lymphocytes, but not with those in granulocytes. Excretion of urinary metabolites during the first week of treatment was correlated with the percentage of the skin surface treated with CT ointment and decreased to background levels within a week after the cessation of treatment. 3-Hydroxybenzo(a)pyrene excretion, but not that of 1-hydroxypyrene, correlated significantly with the levels of DNA adducts in skin that comigrated with benzo(a)pyrene-diol-epoxide-DNA. This study indicates that the DNA adduct levels in mononuclear WBCs can possibly be used as a surrogate for skin DNA after dermal exposure to PAHs.  相似文献   

11.
Several studies suggested that lipoprotein (a)-Lp(a) is an independent atherogenic risk factor. Since non-insulin-dependent diabetes mellitus (NIDDM) is characterized by an increased risk of coronary heart disease (CHD) as related to the general population, the main purpose of our study was to compare the plasma levels of apolipoprotein (a)-(apo) (a) in 30 NIDDM patients hospitalized in our department, and in 20 non-diabetic controls from Timi?oara. Apo (a) values were similar in the two groups (medians, 95% confidence intervals 57 (50-107) in NIDDM versus 58 (51-106) U/l in controls; p = 0.9097). We found weak correlations between apo (a) and hemoglobin A1 (HbA1) (r = 0.42). A significant association was noticed between apo (a) and apo B, both in NIDDM (r = 0.71) and in control subjects (r = 0.81) p < < 0.001. The diabetic patients were screened for microalbuminaria with the MICRAL-test and we compared apo (a) levels in those having albumin excretion values above and under the cut-off point (20 mg/l). Apo (a) concentrations were similar in both samples. We found no association between apo (a) and plasma lipid values. NIDDM patients on fair glycemic control have similar apo (a) concentrations to non-diabetic subjects and they do not seem to be influenced by diabetes duration, HbA1, microalbuminuria and plasma lipid values Apo (a) and apo B are significantly correlated, both in diabetic and non-diabetic subjects.  相似文献   

12.
Attitudes of substance-abusing fathers (N = 214) and mothers (N = 106) entering outpatient treatment toward allowing their custodial children to participate in individual- or family-based interventions were examined. Only 129 parents (40%) reported they would be willing to allow their children to participate in treatment. A significantly greater proportion of mothers reported they would assent to their children participating (N = 58 [55%]) compared with fathers (N = 71 [33%]). Factors associated with parents' attitudes toward their children participating included parents' (a) referral source into treatment, (b) level of psychiatric distress, and (c) substance use frequency in the previous year. Thus, parental reluctance to allow their children to participate appears to be a significant barrier in efforts to intervene with these at-risk children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

13.
Bilirubin kinetics were studied in an isolated, perfused rat liver system using unconjugated (14C) bilirubin (UC(14C)B) and delta-amino (4-14 C) levulinic acid (A(14 C)LA) to derive a suitable compartmental model. Plasma disappearance of UC(14C)B, plasma appearance of conjugated (14c) bilirubin (C(14C)B) and biliary excretion of C(14C)B were followed for 90-120 min following injection of UC(14C)B. Hepatic content of labeled bilirubin 12 min after the injection of UC(14C)B was determined directly in five separate perfusion experiments. UCB was found to reflux back to plasma from liver in two experiments using A(14C)LA. Bilirubin binding to red blood cells (6-8% of the perfusate level) and the components of the perfusion apparatus (4-6% of perfusate level) was estimated by performing a control experiment without the liver. A six compartment model was necessary and adequate to explain the experimental data and current knowledge of bilirubin metabolism: (1) UCB bound to red blood cells and the perfusion apparatus, (2) plasma UCB, (3) liver UCB, (4) liver CB, (5) plasma CB, and (6) bile CB. The proposed model could serve as a reference point for studies of bilirubin kinetics in whole animals for normal and abnormal states.  相似文献   

14.
The authors used 3-phase context preexposure facilitation methodology to study the contribution of N-methyl-D-aspartate (NMDA) receptors in dorsal hippocampus (DH) and the basal lateral region of the amygdala (BLA) to (a) acquisition of the context memory, (b) retrieval of the context memory, (c) acquisition of context-shock association, and (d) retrieval of the context-shock association. The NMDA receptor antagonist D-2-amino-5 phosphonopentanoic acid (D-AP5) was injected into either the DH or BLA prior to (a) the context preexposure phase, (b) the immediate shock phase, or (c) the test for contextual fear. Antagonizing NMDA receptors in the DH impaired the acquisition of the context memory but did not affect its retrieval or retrieval of the fear memory. Antagonizing NMDA receptors with D-AP5 in the BLA impaired acquisition of the context-shock association but had no effect on the expression of fear. However, both DL-AP5 and L-AP5 reduced the expression of fear when they were injected into the amygdala prior to testing for contextual fear. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
A new method for the synthesis of substituted 2-acylallylmetal reagents in a highly regio- and stereoselective fashion involving a three-component assembly of allenes, acyl chlorides, and bimetallic reagents (B-B, Si-Si, and Sn-Sn) catalyzed by phosphine-free palladium complexes is described. Treatment of various allenes (CR(2)R(3)=C=CH(2)) with acyl chlorides (R(1)COCl) and bispinacolatodiboron in the presence of PdCl(2)(CH(3)CN)(2) in toluene at 80 degrees C gave 2-acylallylboronates in moderate to good yields. The acylsilation of allenes with acid chlorides and hexamethyldisilane (5) proceeded successfully in the presence of Pd(dba)(2) in CH(3)CN affording the corresponding allylsilanes (CR(2)R(3)=C(COR(1))CH(2)SiMe(3)) in good to moderate yields. Several chloroformates (R(4)OCOCl) also react with 1,1-dimethylallene (2a) and 5 to afford allylsilanes (CR(2)R(3)=C(COOR(4))CH(2)SiMe(3)) in 66-70% yields. Acylstannation of allenes could also be achieved by slow addition of hexabutylditin (10) to the reaction mixture of acyl chloride (or chloroformate) and allene 2a in CH(3)CN in the presence of Pd(dba)(2) at 60 degrees C; the corresponding 2-substituted allylstannanes were isolated in moderate to good yields. The above catalytic reactions are completely regioselective and highly stereoselective. A mechanism is proposed to account for the catalytic reactions and the stereochemistry.  相似文献   

16.
Enantiomeric and racemic oxazepam (OX), 3-O-methyloxazepam (MeOX), and 3-O-ethyloxazepam (EtOX) were used to study racemization, heteronucleophilic, and homonucleophilic substitution reactions in anhydrous acidic methanol and ethanol. Kinetics of racemization and nucleophilic substitution reactions in nondeuterated and deuterated solvents were determined by circular dichroism spectropolarimetry, chiral stationary phase high-performance liquid chromatography (HPLC), reversed-phase HPLC, and mass spectrometry. Several reactions occurred when (S)-OX, for example, was dissolved in acidic methanol: (1) (S)-OX itself underwent spontaneous racemization, (2) the 3-hydroxyl group of (S)-OX was stereoselectively substituted by the methoxy group of methanol to form MeOX enriched in (S)-MeOX, and (3) the 3-methoxy group of (R)-MeOX was stereoselectively substituted by the methoxy group of methanol to form MeOX enriched in (S)-MeOX, and (4) the 3-methoxy group of (R)-MeOX was stereoselectively substituted by the methoxy group of methanol to form MeOX enriched in (R)-MeOX. Repetitive reactions 3 and 4 eventually resulted in a racemic MeOX. Similar reactions occurred for an enantiomeric OX in acidic ethanol.  相似文献   

17.
Rare earth elements (REEs) as nonessential trace elements are enriched in living organisms and threaten their health. To early detect and reduce REE enrichment in living organisms, scientists are focused on clarifying the enrichment process of REEs in living organisms and its risks. However, the enrichment process of REEs in edible plant cells has remained unclear. Herein, by using interdisciplinary methods and techniques, the enrichment process of lanthanum (La(III)) in the leaf cells of lettuce (Lactuca sativa L.) was investigated. (1) When La(III) exposure dose is 0.5–5 μmol/L, La(III) is enriched outside the plasma membrane (PM). In this zone, La(III) is bound to vitronectin-like protein (VN) to form La–VN complexes; (2) When La(III) exposure dose is 5–20 μmol/L, besides the zone outside the PM, La(III) is also enriched on the PM and bound to arabinogalactan proteins (AGPs) to form La–AGPs complexes; (3) When La(III) exposure dose is 20–140 μmol/L, besides the zone outside and on the PM, La(III) is enriched inside the PM; (4) When La(III) exposure dose is 60–140 μmol/L, malondialdehyde content (an important indicator of invisible damage) significantly increases. Thus, as La(III) exposure dose increases, La(III) gradually migrates from outside the PM to the PM and inside the PM, enriching in these zones in turn. The enriched La(III) will cause invisible damage to lettuce leaf cells and even enter human bodies along food chains. These results provide references for investigating the enrichment process of REEs in plants and its environmental risks, and finding strategies to early detect and reduce REE enrichment in plants.  相似文献   

18.
High-frequency input impedance (Z(f)) measurements, including antiresonances, provide useful noninvasive information on airway geometry and especially airway wall mechanics in the canine and human adult respiratory system. A knowledge of airway wall mechanics would be particularly important in understanding flow limitation phenomena in infants. High-frequency Z(f) has not been measured in infants above 256 Hz, because the high impedance of the infantile respiratory system would be expected to result in low amplitudes of oscillatory flow at higher frequencies. The aim of this study was to develop a technique to measure high-frequency Z(f) in infants and to elucidate the nature of the antiresonance phenomena in the Z(f) spectrum in infants. Z(f) was measured from 32-900 Hz during rapid airflow interruption by the high-speed interrupter technique (HIT) in 18 infants (aged 24-149 weeks) with wheezing disorders. The HIT enables the excitement of higher flow amplitudes at high frequencies using a pseudostep forcing function. In all infants Z(f) showed a mean (SD) first antiresonance (far,1) of 172 (35) Hz (real part of Z(f) at far,1 (Z(f)re(far,1)): 4.9 (1.1) kPa x L(-1) x s) and in five infants a second antiresonance (far,2) of 564 (51) Hz (Z(f)re(far,2): 2.0 (0.7) kPa x L(-1) x s). The antiresonances were found to be related to wave propagation in the airways (acoustic antiresonances), because they increased by a factor of approximately 2 when He-O2 was inhaled. This implies that far,1 and its harmonics are a function of airway wall compliance. In conclusion, the first and second antiresonances may be helpful in understanding flow limitation in wheezing disorders in infants, because flow limitation is related not only to airway diameter but also to airway wall compliance.  相似文献   

19.
PURPOSE: Abnormal growth of smooth muscle cells (SMCs) in small arteries of the eye is associated with hypertension and diabetes, and the complications that they induce. Migration and proliferation of SMCs into the intima are primary mechanisms involved in neointima formation. In aortic SMCs, angiotensin II (AII)-induced proliferation is inhibited by angiotensin type 1 (AT1) receptor antagonist. However, in small artery SMCs, in particular in the circulation of the eye, the effects of AII on migration and proliferation are unknown. METHODS: The effects of AII (10(-6) to 10(-10) M) on migration and proliferation of growth-arrested SMCs of porcine ciliary arteries were studied in the presence and absence of insulin (5 x 10(-10) M) by assaying DNA synthesis (3H-thymidine incorporation), cell number, and movement of SMCs across the membrane of a modified Boyden chamber. RESULTS: In the absence of insulin, only high concentrations (10(-6) to 10(-8) M) of AII induced DNA synthesis and increased cell number (P < 0.05); however, in the presence of insulin (5 x 10(-10) M), AII induced DNA synthesis and cell number at low concentrations (10(-10) M) and in a concentration-dependent manner (P < 0.05). In contrast to proliferation, AII induced SMC migration in a concentration-dependent manner in the absence of insulin (P < 0.05). The AT1 antagonist CGP48933 (10(-8) to 10(-12) M), but not the AT2 antagonist CGP42112 (10(-8) to 10(-12) M), inhibited AII (10(-8) M)-induced proliferation and migration in a concentration-dependent manner (P < 0.05). CONCLUSIONS: Our results suggest that AII is a potent mitogen for SMCs of ophthalmic arteries, an effect that is enhanced in the presence of insulin, and that it may be an important contributor to structural vascular changes in the ophthalmic circulation in hypertension associated with non-insulin dependent diabetes. The inhibition of AII-induced growth by an AT1 antagonist suggests that these drugs may be important therapeutic tools to prevent structural vascular changes in the ophthalmic vasculature under these conditions.  相似文献   

20.
OBJECTIVES: To evaluate the effect of vitamin A supplementation 24 h after delivery on breastmilk retinol concentration. METHODS: Fifty low income women were randomly assigned to a single oral dose of 209 micromol of Vitamin A or none at delivery. Maternal serum and breastmilk retinol levels and infant morbidity and anthropometry were serially assessed. RESULTS: Mean (95% CI) serum retinol levels increased in the supplemented mothers at 2.77 (2.3, 3.2) compared to 1.15 (0.9, 1.4) micromol/l in controls (P < 0.05) and remained at a significantly higher level of 1.59 (1.4, 1.8) micromol/l compared to 1.33 (1.8, 1.5) micromol/l in the control group (P < 0.001) up to a period of three months. Breastmilk retinol concentration was also greater at 24 h after supplementation, mean (CI) 11.34 (9.0, 13.7) micromol/l, compared to 2.95 (2.3, 3.6) micromol/l in the control group (P < 0.0001), and remained higher for the next six months at 1.06 (0.9, , 1.3) micromol/l compared to 0.73 (0.6, 0.8) micromol/l in the control group (P < 0.02). Infants of the supplemented mothers had reduced mean duration of respiratory tract infection of 3.1 (2.7, 3.5) days compared to 3.7 (3.3, 4.2) days (P < 0.03) and mean incidence of febrile illness 0.1 (0.1, 0.1) compared to control infants 0.3 (0.3, 0.3) days, (P < 0.002). CONCLUSION: Vitamin A supplementation of malnourished mothers maintains higher breastmilk retinol concentration for at least six months and reduces the duration of respiratory tract infection and febrile illness in their breastfed infants.  相似文献   

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