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91.
New bronchopulmonary dysplasia (BPD) has been suggested to be a maldevelopment sequence with reduced alveolarisation of the lungs; affected infants then would be predicted to have low lung volumes. The aim of this study was to test that hypothesis by comparing the lung volumes of infants who had had mild-moderate BPD with those without BPD of similar postmenstrual age. Lung volumes of 17 infants who had mild-moderate BPD (oxygen dependent beyond 28 days, but not past term) (BPD infants) were compared to those of 17 infants without BPD (non-BPD infants). All were born at less than 33 weeks of gestation and studied at postmenstrual ages of 33 to 39 weeks. Lung volume was assessed by measurement of functional residual capacity (FRC). The BPD infants had lower lung volumes (median 19.1 ml/kg) than the non-BPD infants (median 26.5 ml/kg) (p=0.0001). The BPD compared to the non-BPD infants were of greater postnatal age (p=0.0003), born at a lower gestational age (p=0.0001) and of lighter birthweight (p=0.0001). Regression analysis, however, demonstrated that lung volume was significantly related to BPD status (p=0.005), independently of postnatal age, birthweight and gestational age. It is concluded that the lower lung volumes of the infants who had had mild-moderate BPD support the hypothesis that new BPD is associated with poor alveolarisation.  相似文献   
92.

Purpose

The aim of this 10-year follow-up study was to determine changes in health-related quality of life (HRQoL) over time among ambulatory persons with MS (PwMS) at the baseline using generic and disease-specific instruments.

Methods

Of 109 independently walking PwMS included in a population-based study in 2002, 77 (70.6 %) were re-assessed in 2012. HRQoL was captured using the 36-Item Short Form Survey Instrument (RAND-36), 15D instrument (15D), and the Multiple Sclerosis Quality of Life-54 (MSQOL-54). Repeated-measures ANOVA and effect size (ES) calculations (Cohen’s d) were used in the statistical analysis.

Results

The RAND-36 physical health composite score (p = 0.003, ES = 0.26) and 15D total score (p = 0.012, ES = 0.25) declined from the baseline levels. In particular, lower scores were observed on the RAND-36 scales of physical functioning (p = 0.001, ES = 0.27), pain (p = 0.020, ES = 0.25), and general health perceptions (p = 0.002, ES = 0.36), on the MSQOL-54 scales of physical functioning (p = 0.001, ES = 0.27), pain (p = 0.040, ES = 0.21), sexual functioning (p = 0.003, ES = 0.43), and satisfaction with sexual functioning (p = 0.012, ES = 0.38), and in the 15D dimensions of mobility (p = 0.004, ES = 0.31) and sexual functioning (p ≤ 0.001, ES = 0.59). Improvement was observed on the RAND-36 scale of social functioning (p = 0.049, ES = 0.25). The other composite scores, scales, and dimensions remained unchanged.

Conclusion

The results of this study suggest that ambulatory PwMS at baseline reported reduced HRQoL in physical functioning after a 10-year follow-up period, while emotional well-being was maintained and social functioning improved. The scores in the other HRQoL dimensions and scales remained unchanged. More long-term population-based studies are needed to precisely determine the development of HRQoL among PwMS.
  相似文献   
93.
Purpose: The aim of this study was to investigate the ability of n-alkenyl succinic anhydrides (n-ASAs) to improve the film-forming characteristics of a novel coating polymer, potato starch acetate degree of substitution 2.8 (SA). n-ASAs were also applied to improve the otherwise brittle properties of ethyl cellulose (EC) aqueous dispersion (Aquacoat®) and EC solvent-based films. Methods: The effectiveness of two n-ASAs, 2-octenyl succinic anhydride (OSA) and 2-dodecen-1-ylsuccinic anhydride were evaluated as plasticizers. Mechanical properties, both water vapor and drug permeabilities, and glass transition temperatures of the cast free films were measured. Triethyl citrate and dibutyl sebacate were used as reference plasticizers. Results: The long hydrocarbon chain of n-ASA, with its accessible carbonyl groups, enabled a strong plasticization effect on the tested polymers. Due to the excellent mechanical properties (i.e., a tough film structure with considerable flexibility) and low permeability of the plasticized films, n-ASAs, and especially OSA proved to be an ideal plasticizer particularly for EC based coatings. Also, the EC aqueous dispersion plasticized with n-ASAs resulted in a markedly enhanced coalescence of the colloidal polymer particles, even at low drying temperatures. Conclusions: In applications where a coating with high flexibility is required, n-ASAs can be used as plasticizers at moderately high concentrations (up to 60–70%, w/w) without losing the high tensile strength, excellent toughness and low permeability of EC and SA films.  相似文献   
94.
95.
Background Irritable bowel syndrome is the most common diagnosis in gastroenterology. Trials suggest certain probiotics to be beneficial. Aim To investigate the effects of multispecies probiotic supplementation (Lactobacillus rhamnosus GG, L. rhamnosus Lc705, Propionibacterium freudenreichii ssp. shermanii JS and Bifidobacterium animalis ssp. lactis Bb12) on abdominal symptoms, quality of life, intestinal microbiota and inflammatory markers in irritable bowel syndrome. Methods Eighty‐six irritable bowel syndrome patients (Rome II criteria) participated in this randomized, placebo‐controlled 5‐month intervention. Patients were randomized to receive daily either multispecies probiotic supplementation or placebo. Irritable bowel syndrome symptoms, quality of life, microarray‐based intestinal microbiota stability (n = 20), serum cytokines and sensitive C‐reactive protein were monitored. Results The composite irritable bowel syndrome score had at 5 months decreased 14 points (95% CI: ?19 to ?9) from baseline with the multispecies probiotic vs. three points (95% CI: ?8 to 1) with placebo (P = 0.0083). Especially, distension and abdominal pain were affected. A stabilization of the microbiota was observed, as the microbiota similarity index increased with the probiotic supplementation (1.9 ± 3.1), while it decreased with placebo (?2.9 ± 1.7). No differences were seen in C‐reactive protein. Conclusions This multispecies probiotic seems to be an effective and safe option to alleviate symptoms of irritable bowel syndrome, and to stabilize the intestinal microbiota.  相似文献   
96.
This paper focuses on study of second and third ring cyclization in anthracycline biosynthesis by a heterologous gene expression. Firstly, anthracycline non-producing Streptomyces peucetius mutant, D2 was heterologously complemented to produce daunomycins with plasmids pSgs44 and pSYE66, which contain putative cyclase genes of S. galilaeus and S. nogalater, respectively. A point mutation in the cyclase gene dpsY of D2 has changed glycine to serine resulting inactivation of the enzyme. Secondly, the putative cyclase gene snoaM from S. nogalater, was expressed in a gene cassette in S. lividans TK24 and S. coelicolor CH999 to study the influence of the cyclase gene on auramycinone production and the impact of endogenous genes on production profiles. The results obtained confirms that a cyclase closing the second and third ring of a polyketide is essential in anthracycline biosynthesis.  相似文献   
97.
To determine the presence of perceptual sensitization and related brain responses we examined 15 patients with fibromyalgia syndrome and 15 healthy controls comparable in age and sex. Multichannel EEG recordings and pain ratings were obtained during the presentation of 800 painful electrical intramuscular and intracutaneous stimuli to the left m. erector spinae and the left m. extensor digitorum. The stimulus intensity was adjusted to 50% between pain threshold and tolerance. Detection and pain thresholds were significantly lower in the fibromyalgia syndrome group. Sensitization occurred for both groups during intramuscular stimulation. In the EEG data the fibromyalgia syndrome patients showed higher N80 amplitudes compared with the healthy controls. Arm stimulation and intramuscular stimulation yielded higher N80 and N150 amplitudes compared with intracutaneous stimulation or stimulation of the back. These results indicate lower pain thresholds in the fibromyalgia syndrome patients after electrical stimulation and a higher N80 amplitude both indicative of enhanced sensory processing in this group.  相似文献   
98.
99.
T Sugimoto  G J Bennett  K C Kajander 《Pain》1990,42(2):205-213
The lumbar and cervical spinal dorsal horns of adult rats with a chronic (8 days) constriction injury of the sciatic nerve on one side (and a sham operation on the other) were examined for signs of transsynaptic degeneration. The incidence of neurons with signs of degeneration (pyknosis and hyperchromatosis; 'dark neurons') was significantly increased in the lumbar dorsal horn on both sides. The ipsilateral lumbar increase was significantly greater than the contralateral increase. There was no increase in the incidence of dark neurons in the cervical dorsal horns of the same rats. The distribution of lumbar dark neurons was similar bilaterally. The majority of the dark neurons were found in the sciatic nerve's territory in laminae I-II. A second group of rats received the same surgery but in addition received a series of 7 daily subconvulsive doses of strychnine. Dark neurons were again found bilaterally (with ipsilateral predominance) in the sciatic nerve's territory in lumbar laminae I-II, but the incidence was significantly greater than that found in the group that did not receive strychnine. The same result was obtained in a third group of strychnine-treated rats when the sham operation was omitted. Thus the appearance of contralateral dark neurons is not dependent on unintentional nerve damage created by the sham procedure. An additional group of rats was sacrificed 8 days after receiving a unilateral sciatic nerve transection, a contralateral sham operation, and the 7 daily strychnine injections. There was no increase in the incidence of dark neurons in any of these rats.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
100.
Antibiotics can cause severe alterations in the gut microflora and promote diarrhoea and overgrowth of pathogenic bacteria. The present study investigated the potency of targeted recombinant beta-lactamase (TRBL) to degrade a beta-lactam antibiotic in the jejunum of fistula-operated beagles. We used different peroral doses of purified beta-lactamase (PenP) of Bacillus licheniformis in enteric-coated pellets together with intravenous ampicillin. Serum and jejunal samples were collected for ampicillin and beta-lactamase analysis. A dose-response effect of TRBL on ampicillin concentrations in the jejunal samples could be observed. The highest doses applied decreased the jejunal ampicillin concentrations to undetectable levels. In the serum samples, the ampicillin concentrations were not affected by the beta-lactamase dose used. Our results indicate that it may be possible to evolve a targeted treatment to degrade beta-lactam antibiotics intestinally and, thus, decrease antibiotic-induced adverse effects on the gut microflora.  相似文献   
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