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951.
A content analysis of 141 articles on breast feeding by discipline revealed differences in the factors considered necessary for breast feeding success and in the criteria used to determine success. Whereas medical articles focused on maternal factors prenatally and infant health post-natally, or the length of time breast feeding was maintained, lay articles focused on the relationship of the mother with her infant (the nursing couple) and the mother's ability to manage breast feeding within the family context. The implications of this discrepancy for nursing practice and research are discussed.  相似文献   
952.
953.
Enterohepatic recirculation (EHR) occurs via biliary excretion and intestinal reabsorption of a drug. Drug recycling through EHR can lead to a change in pharmacokinetic (PK) properties, such as reduced clearance (CL), extended half-life (T(1/2)) and increased plasma exposure (AUC). As a result, EHR may prolong the pharmacological effect of drugs. In the present study, the compound (Cpd A) was found to exhibit EHR in Rhesus monkeys associated with a reduction in CL (from 3.8 to 0.33 Lh(-1), IV; from 2.3 to 0.4 Lh(-1), PO), and an increase in T(1/2) (from 0.9 to 18 h, IV) and in AUC (from 1.5 to 17.4 microg h/mL, IV; from 2.8 to 16.3 microg h/mL, PO), by comparing the PK in the monkeys via the interruption of EHR (bile-duct cannulation) with that in the intact monkeys. A population four-compartment model was constructed based on recirculation loops incorporating all possible inputs (bile secretion, a lag-time model for gall bladder emptying, routes and amounts of a single dose administration) to fully evaluate the EHR of Cpd A. The plasma concentrations versus time profiles predicted from the model had a good fit to the values observed in the subjects and were further simulated with 90% confidence interval to demonstrate its utility. Thus, the model could be applied as a useful tool to evaluate the drugs or compounds that undergo EHR in different species.  相似文献   
954.
955.
Objectives: The Central Massachusetts Oral Health Initiative (CMOHI) aimed to improve access to quality oral health care in central Massachusetts. Methods: A broad‐based public and private organization partnership with local and national funding created a steering committee to organize school administrators, community leaders, and a medical school to collaborate on five goals: advocate for changes in oral health policy, increase oral health care access, provide school‐based dental services for underserved children, establish a Dental General Practice Residency, and educate medical professionals about oral health. Results: A state legislative Oral Health Caucus helped secure sought‐after policy improvements; more regional dentists now accept Medicaid; community health center capacity to provide dental services was expanded; school‐based programs were designed and delivered needed dental services; a dental residency was created; and methods of educating medical professionals were established. Conclusions: Significant sustainable gains in oral health care access were created through our multifaceted approach, ongoing evaluation and communication, coordination of CMOHI partner resources, and collaboration with other involved parties.  相似文献   
956.
PurposeTo compare vascular plugs to coil embolization of the proximal splenic artery and evaluate differences in radiation exposure to the patients.MethodsAn electronic literature search was performed for relevant studies from January 2000 to July 2018 that compared the efficacy of vascular plugs vs coils in splenic artery embolization. Only studies that investigated coil or vascular plug use, without combination with other embolic agents, were included. Meta-analysis was performed using a fixed effects model approach with the inverse variance-weighted average method to determine pooled differences in time to vessel occlusion, procedure time, fluoroscopy time, total number of devices used, and radiation exposure. Heterogeneity was assessed using the I square statistic. Pooled outcomes were compared, and quality assessments were evaluated using the Newcastle Ottawa Scale.ResultsEight studies met inclusion criteria. 81 patients were embolized with vascular plugs and 52 patients with coils only. The most common indication for splenic artery embolization was trauma. Time to vessel occlusion was shorter in the vascular plug group by 7.11 minutes (P = 0.003). Fluoroscopy time was shorter by 13.82 minutes in the vascular plug cohort, and these patients received less radiation (?439 mGy) compared to the coil group (P = 0.006 and P = 0.02, respectively). The number of devices was significantly fewer in the vascular plug group (?3.54; P < 0.001). Procedure time was not statistically significant.ConclusionOur data supports the vascular plug is superior to coils for embolization of the proximal splenic artery with respect to occlusion time, fluoroscopy time, patient radiation exposure, and number occlusive devices used.  相似文献   
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958.
A tissue culture assay for tetrodotoxin, saxitoxin and related toxins   总被引:8,自引:0,他引:8  
In the presence of ouabain, veratridine enhances sodium influx in the mouse neuroblastoma cell line Neuro-2A (ATCC, CCL131), causing cellular swelling and subsequent death. Tetrodotoxin (puffer fish toxin) or saxitoxin (paralytic shellfish poison), both of which block the sodium channel of excitable membranes, antagonize this effect, enabling cell growth to continue. This phenomenon was used as the basis of a new assay for these toxins. It is also possible to estimate the quantity of TTX from the relationship between TTX concentration and percentage of living cells. This new method is simple, inexpensive, and sensitive, and may replace the conventional mouse bioassay.  相似文献   
959.
960.
How Vibrio cholerae spreads around the world and what determines its seasonal peaks in endemic areas are not known. These features of cholera have been hypothesized to be primarily the result of environmental factors associated with aquatic habitats that can now be identified. Since 1997, fortnightly surveillance in 4 widely separated geographic locations in Bangladesh has been performed to identify patients with cholera and to collect environmental data. A total of 5670 patients (53% <5 years of age) have been studied; 14.3% had cholera (10.4% due to V. cholerae O1 El Tor, 3.8% due to O139). Both serogroups were found in all locations; outbreaks were seasonal and often occurred simultaneously. Water-use patterns showed that bathing and washing clothes in tube-well water was significantly protective in two of the sites. These data will be correlated with environmental factors, to develop a model for prediction of cholera outbreaks.  相似文献   
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