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181.
BACKGROUND: Administering probiotics can prevent or cure some forms of diarrhea. The efficacy of probiotic Escherichia coli Nissle 1917 (EcN) in infants and toddlers with diarrhea >4 days was tested by a double-blind trial. METHODS: One hundred fifty-one children aged 1-47 months with nonspecific diarrhea were randomized to receive either EcN suspension (N = 75) or placebo (N = 76). Diarrhea had to meet the following definition: >3 watery or loose nonbloody stools in 24 hours of a diarrheal episode persisting for >4 consecutive days but < or =14 days. All children were well nourished or only moderately malnourished, mildly dehydrated, and received oral rehydration at study commencement. They were treated orally with 1-3 mL EcN suspension (1 mL contains 10 viable cells) or placebo daily for 21 days. Primary objective was to confirm a better response rate (reduction of daily stool frequency to < or =3 watery or loose stools over > or =4 days) with EcN. RESULTS: The 7-day response was higher for the EcN group than placebo (EcN 78.7%, placebo 59.2%). Significant differences were observed on days 14 (EcN 93.3%, placebo 65.8%, P = 0.0017) and 21 (EcN 98.7%, placebo 71.1%, P < 0.001). Kaplan-Meier survival analysis resulted in a significant difference of 3.3 days between the groups (P < 0.0001); median time to response for EcN was 2.4 and 5.7 for placebo. EcN was safe and well tolerated. CONCLUSIONS: In the conditions of this trial EcN was a suitable remedy for diarrhea >4 days in young children.  相似文献   
182.
Peri-stimulus time histograms (PSTHs) reveal the temporal distribution of action potentials, averaged over many stimulus presentations. PSTHs have been used as model responses to solve the classification problem, in which a single response (i.e., spike train) is assigned to one of a set of response models evoked by a set of stimuli. In this study, we developed and applied a sparse firing frequency-based method to classify individual spike trains of slowly adapting pulmonary stretch receptors (SARs). Extracellularly recorded individual SAR spike trains were evoked by one of three different lung inflation volumes in anesthetized, paralyzed adult male New Zealand White rabbits. Three different PSTH-based firing frequency response models (i.e., one for each stimulus) were constructed from two-thirds of the responses to the 600 inflations presented at each volume, while the remaining one-third were used as responses to be classified. An instantaneous firing frequency representation of each remaining "test response" was computed from their individual spike trains, using one of two forms: sparse and filled. The sparse format assigned instantaneous firing rate values only in bins that contained spikes, while the filled format assigned values to intervening bins too. Classification was performed by computing the Euclidean distance between the response spike trains and the three PSTH-based models using both sparse and filled representations. When comparing the two representations with regard to classification accuracy, we found that the sparse representation does not diminish performance appreciably, while reducing computational burden significantly.  相似文献   
183.
Lung cancer from radon or (239)plutonium exposure has been linked to alpha-particles that damage DNA through large deletions and point mutations. We investigated the involvement of an epigenetic mechanism, gene inactivation by promoter hypermethylation in adenocarcinomas from plutonium-exposed workers at MAYAK, the first Russian nuclear enterprise established to manufacture weapons plutonium. Adenocarcinomas were collected retrospectively from 71 workers and 69 non-worker controls. Lung adenocarcinomas were examined from workers and non-worker controls for methylation of the CDKN2A (p16), O(6)-methylguanine-DNA methyltransferase (MGMT), death associated protein kinase (DAP-K), and Ras effector homolog 1 genes (RASSF1A). The prevalence for methylation of the MGMT or DAP-K genes did not differ between workers and controls, while a higher prevalence for methylation of the RASSF1A gene was seen in tumors from controls. In marked contrast, the prevalence for methylation of p16, a key regulator of the cell cycle, was increased significantly (P = 0.03) in tumors from workers compared with non-worker controls. Stratification of plutonium exposure into tertiles also revealed a striking dose response for methylation of the p16 gene (P = 0.008). Workers in the plutonium plant where exposure to internal radiation was highest had a 3.5 times (C.I. 1.5, 8.5; P = 0.001) greater risk for p16 methylation in their tumors than controls. This increased probability for methylation approximated the 4-fold increase in relative risk for adenocarcinoma in this group of workers exposed to plutonium. In addition, a trend (P = 0.08) was seen for an increase in the number of genes methylated (> or =2 genes) with plutonium dose. Here we demonstrate that exposure to plutonium may elevate the risk for adenocarcinoma through specifically targeting the p16 gene for inactivation by promoter methylation.  相似文献   
184.
Summary: Hydrophilic polymeric films based on blends of hydroxyethylcellulose and maleic acid‐co‐methyl vinyl ether were produced by casting from aqueous solutions. The physicochemical properties of the blends have been assessed using Fourier transform infrared spectroscopy, thermal gravimetric analysis, differential scanning calorimetry, dielectric spectroscopy, etc. The pristine films exhibit complete miscibility due to the formation of intermacromolecular hydrogen bonding. The thermal treatment of the blend films leads to cross‐linking via intermacromolecular esterification and anhydride formation. The cross‐linked materials are able to swell in water and their swelling degree can be easily controlled by temperature and thermal treatment time. The formation of the crosslinks is apparent in the dynamic properties of the blends as observed through the mechanical relaxation and dielectric relaxation spectra. The dielectric characteristics of the material are influenced by the effects of change in the local structure of the blend on the ionic conduction processes and the rate of dipolar relaxation. Separation of these processes is attempted using the dielectric modulus method. Significant deviations from a simple additive rule of mixing on the activation energy are observed consistent with hydrogen bonding and crosslinking of the matrix. This paper indicates a method for the creation of films with good mechanical and physical characteristics by exposing the blends to a relatively mild thermal treatment.

Scheme of hydrogen bonding between hydroxyethylcellulose and maleic acid‐co‐methyl vinyl ether.  相似文献   

185.
The location of dominant pacemaker region in isolated rat sinoatrial node in the presence of different concentrations of norepinephrine is determined by intracellular recording of action potential. A linear relationship is revealed between the concentration of norepinephrine and the shift of pacemaker zone along the node axis within physiological concentrations of the transmitter. At high concentrations norepinephrine affects primarily the parameters of action potential in pacemaker cells. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 125, No. 3, pp. 337–339, March, 1998  相似文献   
186.

Background

Perioperative care of patients undergoing colon resection requires a multidisciplinary approach by the operating surgeon, residents, and nurses. Operations performed on Monday take full advantage of hospital resources throughout the week to meet expected discharge by Friday. In a current health care environment of diminishing means, improving the timing of surgery in relation to expected length of stay may play an important role in preserving health care resources.

Methods

A retrospective review of a prospectively collected colorectal surgical database identified all patients who underwent segmental colon resection at a single tertiary care referral center from 2004 to 2010. Length of stay for patients undergoing elective open and minimally invasive segmental colectomy was compared for Monday versus Tuesday through the weekend. Patient and surgeon demographics were recorded as well as postoperative outcomes and complications.

Results

A total of 868 segmental colectomies were performed during the study period. Length of stay was significantly decreased by .73 days (P < .01) for all segmental colectomies performed on Monday compared with those performed Tuesday through Sunday. There was also a significant decrease in length of stay looking independently at right (.96 days, P < .01) and left or sigmoid colectomies (.56 days, P < .01). There was no significant difference in patient or surgeon demographics to account for this difference.

Conclusions

Segmental colectomies have a significantly decreased length in stay when performed on Monday compared with the rest of the week. The decrease is independent of surgeon, comorbidities, and complications. This difference may be the result of patients' taking full advantage of hospital resources and ancillary support. Cost-effective measures may be evaluated and directed at adjustment of resources available throughout the week to reduce length of stay.  相似文献   
187.
AIDS and Behavior - Although HIV incidence is rising among gay, bisexual, and other men (MSM) and transgender people who have sex with men (TSM) in Kazakhstan, whether stigmatizing attitudes and...  相似文献   
188.
Conformational changes in adsorbed fibrinogen may enhance the exposure of platelet adhesive sites that are inaccessible in solution. To test this hypothesis, mass spectrometric methods were developed to quantify chemical modification of lysine residues following adsorption of fibrinogen to biomaterials. The quantitative method used an internal standard consisting of isotope-labeled fibrinogen secreted by human HepG2 cells in culture. Lysine residues in the internal standard were partially reacted with NHS-biotin. For the experimental samples, normal human fibrinogen was adsorbed to poly(ethylene terephthalate) (PET) particles. The adsorbed fibrinogen was reacted with NHS-biotin and then eluted from the particles. Constant amounts of internal standard were added to sample fibrinogen and analyzed by liquid chromatography/tandem mass spectrometry. Biotinylation of the lysine residue in the platelet-adhesive gamma chain dodecapeptide (GCDP) was quantified by comparison with the internal standard. Approximately 80% of the GCDP peptides were biotinylated when fibrinogen was reacted with NHS-biotin in solution or adsorbed onto PET. These results are generally consistent with previous antibody binding studies and suggest that other regions of fibrinogen may be crucial in promoting platelet adhesion to materials. The results do not directly address but are consistent with the hypothesis that only activated platelets adhere to adsorbed fibrinogen.  相似文献   
189.
The standard diagnosis of multiple myeloma by flow cytometry is based on selection of population of CD38+/CD138+ positives cells. As the result treatment with proteasome inhibitors, CD138 may be underexpressed on atypical plasma cells. Thus, in order to improve this strategy, recently new CD138-independent method, based on CD38 positivity of plasma cells was developed. We present an unusual case of CD138? negative multiple myeloma which had become double CD138?/CD38? negative after treatment with daratumumab by which we would like to illustrate potential pitfalls of both strategies.  相似文献   
190.
Rice husk is a large-tonnage waste left from rice production. It is not subject to humification and therefore becomes a serious environmental pollutant. Due to the presence of two essential elements—carbon and silicon—in its composition, rice husk is a promising organo-mineral raw material. The known methods for processing of rice husk are associated with the formation of even more aggressive waste. The creation of a waste-free technology for processing this plant material requires a detailed study. Rice husk of Kyzylorda oblast was studied using IR, SEM, TA, TPD-MS, EPR, and TEM methods. It was determined that under a temperature up to 500 °C, the ligno-carbohydrate component of rice husk decomposes almost completely. Three main peaks are recorded during the decomposition: hemicellulose at 200 °C, cellulose at 265 °C, and lignin at 350–360 °C. This process is endothermic. However, above of 300 °C the exothermic reactions associated with the formation of new substances and condensation processes in the solid residue begin to prevail. This explains the increase in the concentration of paramagnetic centers (PMCs) in products of rice husk carbonization in the range of up to 450 °C. Further increase in temperature leads to a decrease in the number of PMCs as a result of carbon graphite-like structures formation. The silicon–carbon product of rice husk carbonization (nanocomposite) is formed by interconnected nanoscale particles of carbon and silicon dioxide, the modification of which depends on the temperature of carbonization. The obtained data allow management of the rice husk utilization process while manufacturing products in demand based on ecofriendly technologies.  相似文献   
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