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1.

Background  

The loss of perfluorocarbon (PFC) vapour in the expired gases during partial liquid ventilation should be minimized both to prevent perfluorocarbon vapour entering the atmosphere and to re-use the recovered PFC liquid.  相似文献   

2.

Background  

The aim of this study was to evaluate the biological and pharmaceutical activities of 14 amphiphilic liquid-crystalline compounds (LCs), i.e, phenylpyrimidine derivatives possessing D-glucamine and cyanobiphenyl derivatives with a terminal hydroxyl unit.  相似文献   

3.

Background  

Rejection of false positive peptide matches in database searches of shotgun proteomic experimental data is highly desirable. Several methods have been developed to use the peptide retention time as to refine and improve peptide identifications from database search algorithms. This report describes the implementation of an automated approach to reduce false positives and validate peptide matches.  相似文献   

4.

Background  

Somatropin is recombinant human growth hormone (GH) used for the treatment of growth failure in children and GH deficiency in adults. Two concentrations of a liquid formulation have been developed: 5.83 and 8.0 mg/mL. This trial compared the pharmacokinetics (PK), safety and tolerability of these two liquid concentrations against the freeze-dried (FD) formulation in healthy volunteers.  相似文献   

5.

Background  

The taxanes paclitaxel and docetaxel have traditionally been used in high doses every third week in the treatment of cancer. Lately there has been a trend towards giving weekly low doses to improve the therapeutic index. This article describes the development of high performance liquid chromatographic (HPLC) methods suitable for monitoring taxane levels in patients, focusing on patients receiving low-dose therapy.  相似文献   

6.

Background  

Successful application of growth inhibition techniques for quantitative determination of bacteriocins relies on the sensitivity of the applied indicator microorganism to the bacteriocin to which is exposed. However, information on indicator microorganisms' performance and comparisons in bacteriocin determination with bioassays is almost non-existing in the literature. The aim of the present work was to evaluate the parameter "indicator microorganism" in bioassays carried out on solid -agar diffusion assay- and liquid -turbidometric assay- substrates, applied in the quantification of the most studied bacteriocin nisin.  相似文献   

7.

Aims

The aim of the study was to develop an approach to enrich ionic liquid tolerant micro‐organisms that efficiently decompose lignocellulose in a thermophilic and high‐solids environment.

Methods and Results

High‐solids incubations were conducted, using compost as an inoculum source, to enrich for thermophilic communities that decompose switchgrass in the presence of the ionic liquid 1‐ethyl‐3‐methylimidazolium acetate ([C2mim][OAc]). Ionic liquid levels were increased from 0 to 6% on a total weight basis incrementally. Successful enrichment of a community that decomposed lignocellulose at 55°C in the presence of 6% [C2mim][OAc] was achieved, when the [C2mim][OAc] level was increased stepwise from 2% to 4% to 5% to 6%. Pyrosequencing results revealed a shift in the community and a sharp decrease in richness, when thermophilic conditions were applied.

Conclusions

A community tolerant to a thermophilic, high‐solids environment containing 6% [C2mim][OAc] was enriched from compost. Gradually increasing [C2mim][OAc] concentrations allowed the community to adapt to [C2mim][OAc].

Significance and Impact of the Study

A successful approach to enrich communities that decompose lignocellulose under thermophilic high‐solids conditions in the presence of elevated levels of [C2mim][OAc] has been developed. Communities yielded from this approach will provide resources for the discovery of enzymes and metabolic pathways relevant to biomass pretreatment and fuel production.  相似文献   

8.
We reportedchanges in alveolar-arterial PO2 gradient,ventilation-perfusion heterogeneity, and arterial-alveolarPCO2 gradient during partial liquid ventilation(PLV) in healthy piglets (E. A. Mates, P. Tarczy-Hornoch, J. Hildebrandt, J. C. Jackson, and M. P. Hlastala. In: OxygenTransport to Tissue XVII, edited by C. Ince. New York: Plenum,1996, vol. 388, p. 585-597). Here we develop two mathematicalmodels to predict transient and steady-state (SS) gas exchangeconditions during PLV and to estimate the contribution of diffusionlimitation to SS arterial-alveolar differences. In the simplest model,perfluorocarbon is represented as a uniform flat stirred layer and, ina more complex model, as an unstirred spherical layer in a ventilatedterminal alveolar sac. Time-dependent solutions of both models showthat SS is established for various inert and respiratory gases within5-150 s. In fluid-filled unventilated terminal units, all times toSS increased sometimes by hours, e.g., SF6 exceeded 4 h. SSsolutions for the ventilated spherical model predicted minorend-capillary disequilibrium of inert gases and significantdisequilibrium of respiratory gases, which could explain a largeportion of the arterial-alveolar PCO2 gradient measured during PLV (14). We conclude that, during PLV, diffusion gradients for gases are generally small, except for CO2.

  相似文献   

9.

Background  

Dual-axis swallowing accelerometry has recently been proposed as a tool for non-invasive analysis of swallowing function. Although swallowing is known to be physiologically modifiable by the type of food or liquid (i.e., stimuli), the effects of stimuli on dual-axis accelerometry signals have never been thoroughly investigated. Thus, the objective of this study was to investigate stimulus effects on dual-axis accelerometry signal characteristics. Signals were acquired from 17 healthy participants while swallowing 4 different stimuli: water, nectar-thick and honey-thick apple juices, and a thin-liquid barium suspension. Two swallowing tasks were examined: discrete and sequential. A variety of features were extracted in the time and time-frequency domains after swallow segmentation and pre-processing. A separate Friedman test was conducted for each feature and for each swallowing task.  相似文献   

10.

Background  

Stagonospora nodorum, a fungal ascomycete in the class dothideomycetes, is a damaging pathogen of wheat. It is a model for necrotrophic fungi that cause necrotic symptoms via the interaction of multiple effector proteins with cultivar-specific receptors. A draft genome sequence and annotation was published in 2007. A second-pass gene prediction using a training set of 795 fully EST-supported genes predicted a total of 10762 version 2 nuclear-encoded genes, with an additional 5354 less reliable version 1 genes also retained.  相似文献   

11.

Background  

Pituitary adenomas, the third most common intracranial tumor, comprise nearly 16.7% of intracranial neoplasm and 25%-44% of pituitary adenomas are prolactinomas. Prolactinoma represents a complex heterogeneous mixture of cells including prolactin (PRL), endothelial cells, fibroblasts, and other stromal cells, making it difficult to dissect the molecular and cellular mechanisms of prolactin cells in pituitary tumorigenesis through high-throughout-omics analysis. Our newly developed immuno-laser capture microdissection (LCM) method would permit rapid and reliable procurement of prolactin cells from this heterogeneous tissue. Thus, prolactin cell specific molecular events involved in pituitary tumorigenesis and cell signaling can be approached by proteomic analysis.  相似文献   

12.

Background

Repeated bronchoalveolar lavage (BAL) has been used in animals to induce surfactant depletion and to study therapeutical interventions of subsequent respiratory insufficiency. Intratracheal administration of surface active agents such as perfluorocarbons (PFC) can prevent the alveolar collapse in surfactant depleted lungs. However, it is not known how BAL or subsequent PFC administration affect the intracellular and intraalveolar surfactant pool.

Methods

Male wistar rats were surfactant depleted by BAL and treated for 1 hour by conventional mechanical ventilation (Lavaged-Gas, n = 5) or partial liquid ventilation with PF 5080 (Lavaged-PF5080, n = 5). For control, 10 healthy animals with gas (Healthy-Gas, n = 5) or PF5080 filled lungs (Healthy-PF5080, n = 5) were studied. A design-based stereological approach was used for quantification of lung parenchyma and the intracellular and intraalveolar surfactant pool at the light and electron microscopic level.

Results

Compared to Healthy-lungs, Lavaged-animals had more type II cells with lamellar bodies in the process of secretion and freshly secreted lamellar body-like surfactant forms in the alveoli. The fraction of alveolar epithelial surface area covered with surfactant and total intraalveolar surfactant content were significantly smaller in Lavaged-animals. Compared with Gas-filled lungs, both PF5080-groups had a significantly higher total lung volume, but no other differences.

Conclusion

After BAL-induced alveolar surfactant depletion the amount of intracellularly stored surfactant is about half as high as in healthy animals. In lavaged animals short time liquid ventilation with PF5080 did not alter intra- or extracellular surfactant content or subtype composition.  相似文献   

13.
14.

Background

Recent studies of Lactobacillus delbrueckii subsp. bulgaricus GLB44 plus a proton‐pump inhibitor (PPI) reported cures of more than 90% of patients with active Helicobacter pylori infections.

Aim

To confirm the high H. pylori cure rates reported previously.

Method

A pilot study was done in healthy H. pylori‐infected volunteers using 3‐gram sachet (3 billion cells) of L. delbrueckii GLB44 plus 22.3 mg of esomeprazole b.i.d., for 14 days. The result was determined by urea breath testing 4 weeks after therapy. Stopping rules required for ending enrollment if less than 3 of the first 10 subjects were cured.

Results

Nine subjects were entered and because all failed to achieve negative urea breath test, the stopping rule required the study to end.

Conclusion

We were unable to confirm reports of achieving a high H. pylori cure rate with L. delbrueckii GLB44 plus a PPI.  相似文献   

15.

Background

We evaluated whether menstrual cycle phase influences the assessment of tubal patency by hysterosalpingography (HSG) in baboons.

Methods

Retrospective analysis of baseline tubal patency studies and serum estradiol (E2) and progesterone (P4) values obtained from female baboons used as models for development of non‐surgical permanent contraception in women. The main outcome measure was bilateral tubal patency (BTP) in relationship with estradiol level.

Results

Female baboons (n = 110) underwent a single (n = 81), two (n = 26), or three (n = 3) HSG examinations. In 33/142 (23%) HSG examinations, one or both tubes showed functional occlusion (FO). The median E2 in studies with BTP (49 pg/mL) was significantly higher than in those studies with FO (32 pg/mL, P = .005). Among 18 animals with repeat examinations where serum E2 changed from <60 to ≥ 60 pg/mL, 13 results changed from FO to BTP (P = .0001). No sets showed a change from BTP to FO with an increase in estradiol.

Conclusion

In baboons, functional occlusion of the fallopian tube is associated with low estradiol levels, supporting a role for estrogen‐mediated relaxation of the utero‐tubal junction.  相似文献   

16.

Aims

Nine commercial DNA extraction kits were evaluated for the isolation of DNA from 10‐fold serial dilutions of Bacillus anthracis spores using quantitative real‐time PCR (qPCR). The three kits determined by qPCR to yield the most sensitive and consistent detection (Epicenter MasterPure Gram Positive; MoBio PowerFood; ABI PrepSeq) were subsequently tested for their ability to isolate DNA from trace amounts of B. anthracis spores (approx. 6·5 × 101 and 1·3 × 102 CFU in 25 ml or 50 g of food sample) spiked into complex food samples including apple juice, ham, whole milk and bagged salad and recovered with immunomagnetic separation (IMS).

Methods and Results

The MasterPure kit effectively and consistently isolated DNA from low amounts of B. anthracis spores captured from food samples. Detection was achieved from apple juice, ham, whole milk and bagged salad from as few as 65 ± 14, 68 ± 8, 66 ± 4 and 52 ± 16 CFU, respectively, and IMS samples were demonstrated to be free of PCR inhibitors.

Conclusions

Detection of B. anthracis spores isolated from food by IMS differs substantially between commercial DNA extraction kits; however, sensitive results can be obtained with the MasterPure Gram Positive kit.

Significance and Impact of the Study

The extraction protocol identified herein combined with IMS is novel for B. anthracis and allows detection of low levels of B. anthracis spores from contaminated food samples.  相似文献   

17.
Mates, Elisabeth A., Jacob Hildebrandt, J. Craig Jackson,Peter Tarczy-Hornoch, and Michael P. Hlastala. Shunt and ventilation-perfusion distribution during partial liquid ventilation inhealthy piglets. J. Appl. Physiol.82(3): 933-942, 1997.Replacing gas in the lung withperfluorocarbon fluids (PFC) and periodically ventilating with a gas[partial liquid ventilation (PLV)] has been shown toimprove oxygenation in models of respiratory distress syndrome. Wehypothesized that the addition of PFC to healthy lungs would result inshunt, diffusion impairment, and increased ventilation-perfusion(A/) heterogeneity.Previously, Mates et al. showed thatO2 shunt and arterial-alveolarCO2 difference increased linearlywith dose in piglets given graded intratracheal doses of PFC (10, 20, and 30 ml/kg followed by mechanical ventilation with 100%O2) (E. A. Mates, J. C. Jackson, J. Hildebrandt, W. E. Truog, T. A. Standaert, and M. P. Hlastala. In: Oxygen Transport to TissueXVI, 1994, p. 427-435). Here we reportA/ distribution inthe same animals, showing a 50% increase inA/ heterogeneity during PLV independent of PFC dose. Ventilation heterogeneity was themajor factor in this increase, and there was no significant change indead space ventilation. We also report on five animals given a single20 ml/kg dose of PFC and followed for 3 h. They showed an increase inshunt during PLV but no change in arterial-alveolar CO2 difference.

  相似文献   

18.

Aim

Whether intraspecific spatial patterns in body size are generalizable across species remains contentious, as well as the mechanisms underlying these patterns. Here we test several hypotheses explaining within-species body size variation in terrestrial vertebrates including the heat balance, seasonality, resource availability and water conservation hypotheses for ectotherms, and the heat conservation, heat dissipation, starvation resistance and resource availability hypotheses for endotherms.

Location

Global.

Time period

1970–2016.

Major taxa studied

Amphibians, reptiles, birds and mammals.

Methods

We collected 235,905 body size records for 2,229 species (amphibians = 36; reptiles = 81; birds = 1,545; mammals = 567) and performed a phylogenetic meta-analysis of intraspecific correlations between body size and environmental variables. We further tested whether correlations differ between migratory and non-migratory bird and mammal species, and between thermoregulating and thermoconforming ectotherms.

Results

For bird species, smaller intraspecific body size was associated with higher mean and maximum temperatures and lower resource seasonality. Size–environment relationships followed a similar pattern in resident and migratory birds, but the effect of resource availability on body size was slightly positive only for non-migratory birds. For mammals, we found that intraspecific body size was smaller with lower resource availability and seasonality, with this pattern being more evident in sedentary than migratory species. No clear size–environment relationships were found for reptiles and amphibians.

Main conclusions

Within-species body size variation across endotherms is explained by disparate underlying mechanisms for birds and mammals. Heat conservation (Bergmann's rule) and heat dissipation are the dominant processes explaining biogeographic intraspecific body size variation in birds, whereas in mammals, body size clines are mostly explained by the starvation resistance and resource availability hypotheses. Our findings contribute to a better understanding of the mechanisms behind species adaptations to the environment across their geographic distributions.  相似文献   

19.

Aim

In this study, the biological variation for improvement of the nutritive value of wheat straw by 12 Ceriporiopsis subvermispora, 10 Pleurotus eryngii and 10 Lentinula edodes strains was assessed. Screening of the best performing strains within each species was made based on the in vitro degradability of fungal‐treated wheat straw.

Methods and Results

Wheat straw was inoculated with each strain for 7 weeks of solid state fermentation. Weekly samples were evaluated for in vitro gas production (IVGP) in buffered rumen fluid for 72 h. Out of the 32 fungal strains studied, 17 strains showed a significantly higher (< 0·05) IVGP compared to the control after 7 weeks (227·7 ml g?1 OM). The three best Ceriporiopsis subvermispora strains showed a mean IVGP of 297·0 ml g?1 OM, while the three best P. eryngii and L. edodes strains showed a mean IVGP of 257·8 and 291·5 ml g?1 OM, respectively.

Conclusion

Ceriporiopsis subvermispora strains show an overall high potential to improve the ruminal degradability of wheat straw, followed by L. edodes and P. eryngii strains.

Significance and Impact of the Study

Large variation exists within and among different fungal species in the valorization of wheat straw, which offers opportunities to improve the fungal genotype by breeding.  相似文献   

20.

Aims

The objective was to determine the effect of the isoflavone biochanin A (BCA) on rumen cellulolytic bacteria and consequent fermentative activity.

Methods and Results

When bovine microbial rumen cell suspensions (n = 3) were incubated (24 h, 39°C) with ground hay, cellulolytic bacteria proliferated, short‐chain fatty acids were produced and pH declined. BCA (30 μg ml?1) had no effect on the number of cellulolytic bacteria or pH, but increased acetate, propionate and total SCFA production. Addition of BCA improved total digestibility when cell suspensions (n = 3) were incubated (48 h, 39°C) with ground hay, Avicel, or filter paper. Fibrobacter succinogenes S85, Ruminococcus flavefaciens 8 and Ruminococcus albus 8 were directly inhibited by BCA. Synergistic antimicrobial activity was observed with BCA and heat killed cultures of cellulolytic bacteria, but the effects were species dependent.

Conclusions

These results indicate that BCA improves fibre degradation by influencing cellulolytic bacteria competition and guild composition.

Significance and Impact of the Study

BCA could serve as a feed additive to improve cellulosis when cattle are consuming high‐fibre diets. Future research is needed to evaluate the effect of BCA on fibre degradation and utilization in vivo.  相似文献   

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