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Rotaviruses are the leading cause and coronaviruses are the major contributors of acute gastroenteritis in the young of various mammalian and avian species. Despite numerous trials and decades of research, vaccines have limited efficacy particularly for calves. As an alternative method of controlling infection, we have investigated broad spectrum antiviral agents that are not discriminatory among various viruses. This report involves testing a variety of adsorbent agents including charcoal, clay, and clay minerals to adsorb rotavirus and coronavirus in vitro. Results revealed that all the adsorbent agents had good to excellent capability of adsorbing rotavirus and excellent capability of adsorbing coronavirus. Percent adsorptions ranged from 78.74% to 99.89% for rotavirus and 99.99% for coronavirus; while sand (negative control) was < 0.01%. A high affinity binding was present as determined by a low percent desorption (0.06-3.09%). However, the adsorbent bound virus complex retained, and may have actually enhanced, infectivity.  相似文献   
13.
Activation of K-ras gene by point mutations, a common finding in lung adenocarcinomas, has been suggested to decrease patient survival. We investigated 109 lung adenocarcinomas, mostly small, peripheral, stage I tumours (81/109) for presence of K-ras gene mutations at codons 12 and 13. Mutations were detected by denaturing gradient gel electrophoresis analysis of specific sequences amplified by polymerase chain reaction from DNA extracted from archival pathological material. Thirty-three of 109 (30.3%) tumours showed mutations at codon 12 (28/33, 84.8%) or 13 (5/33, 15.2%) of the gene. Mutations and type of nucleotide substitutions were differently distributed among cytological subtypes, being more prevalent among less differentiated (G2 and G3) tumours and among bronchial than bronchiolo-alveolar type adenocarcinomas. Survival analysis showed an adverse effect of K-ras mutation on survival, restricted to stage I tumours. Median survival for 81 stage I patients was 30 months for non-mutated tumours versus 20 months for mutated tumours (p = 0.016). Multivariate analysis showed that age of patient (p = 0.001) and K-ras mutation status (p = 0.04) were the only independent factors influencing survival significantly. These data strengthen the hypothesis that K-ras gene mutations may be useful in identifying a subgroup of patients with poor outcome.  相似文献   
14.
Acute graft rejection and delayed function are considered to be the major risk factors of short-term as well as long-term graft survival. We studied the impact of these factors on graft outcome among 109 renal transplant recipients. All recipients were treated with triple drug protocol. The recipients were divided into two groups: I group included 57 patients with delayed graft function (DGF), II group included 52 patients with immediate graft function (IGF). We studied graft survival, incidence of acute rejection, serum creatinine levels and the cause of graft loss for patients in both groups. Acute rejection episodes occurred in 49% of patients from DGF group and 45% of patients from IGF group. Graft survival in IGF group was better than in DGF group. Actuarial graft survival at 1, 2, 3 and 4 years in examined groups was 84%, 82%, 72%, 65% vs. 92%, 86%, 84%, 84%, respectively. One-year graft survival in patients with acute rejection from DGF group and IGF group was significantly lower than in patients who remained rejection free (69%, 74% vs. 94%, 96%). We concluded that delayed graft function decreases long-term graft survival, while immediate graft function has an excellent impact on graft outcome. Acute graft rejection is the strongest risk factor of graft loss.  相似文献   
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Critics of Kohlberg's moral theory today focus on the content of his theory and more specifically on its justice-orientated moral concept. This has led to the well-known 'justice-care debate'. The purpose of this article is to critically examine the validity of Kohlberg's moral theory for research in nursing ethics from a caring perspective (referring to the content) as well as from a cognitive-structural perspective (referring to the basic assumptions of the model). The analysis points to the usefulness and value of the cognitive-structural model to empirically study nurses' ethical behaviour; the content of Kohlberg's model, however, needs to be adapted by adding a caring perspective as well as some personal and situational variables. An adjusted version of Kohlberg's model is proposed and discussed.  相似文献   
17.
We used melanophores, cells specialized for regulated organelle transport, to study signaling pathways involved in the regulation of transport. We transfected immortalized Xenopus melanophores with plasmids encoding epitope-tagged inhibitors of protein phosphatases and protein kinases or control plasmids encoding inactive analogues of these inhibitors. Expression of a recombinant inhibitor of protein kinase A (PKA) results in spontaneous pigment aggregation. alpha-Melanocyte-stimulating hormone (MSH), a stimulus which increases intracellular cAMP, cannot disperse pigment in these cells. However, melanosomes in these cells can be partially dispersed by PMA, an activator of protein kinase C (PKC). When a recombinant inhibitor of PKC is expressed in melanophores, PMA-induced pigment dispersion is inhibited, but not dispersion induced by MSH. We conclude that PKA and PKC activate two different pathways for melanosome dispersion. When melanophores express the small t antigen of SV-40 virus, a specific inhibitor of protein phosphatase 2A (PP2A), aggregation is completely prevented. Conversely, overexpression of PP2A inhibits pigment dispersion by MSH. Inhibitors of protein phosphatase 1 and protein phosphatase 2B (PP2B) do not affect pigment movement. Therefore, melanosome aggregation is mediated by PP2A.  相似文献   
18.
A psychrotrophic yeast, Rhodotorula glutinis KUJ 2731, isolated from soil, effectively produced an extracellular endo-beta-glucanase (EC 3.2.1.4). The enzyme was monomeric, and the molecular mass was about 40,000 Da. The N-terminal amino acid sequence was H-Ser-Leu-Pro- Lys-Leu-Gly-Gly-Val-Asp-Leu-Ala-Gly-Leu-Asp-Ile-Gly-Lys-Asp-Lys-Asn-. alpha-Helix content was calculated to be about 32.6%. The isoelectric point was 8.57. The activation energy was 20.9 kJ/mol, which was much smaller than that of mesophilic enzymes. The enzyme was active at temperatures from 0 to 70 degrees C, with a highest initial velocity at 50 degrees C similar to other psychrotrophic enzymes. The enzyme was inhibited by Hg2+. The enzyme catalyzed hydrolysis of carboxymethyl cellulose with an apparent K(m) of 1.1% and Vmax of 556 mumol/min/mg. Products from the enzymatic hydrolysis of carboxymethyl cellulose by the enzyme were glucose, cellobiose, and cellotriose. The enzyme also catalyzed the transglycosylation of p-nitrophenyl-beta-cellotrioside to cellotetraose.  相似文献   
19.
The medical management of Crohn's disease has changed in recent years, but the mainstay of treatment is still prednisone. A substantial fraction of steroid-treated patients are refractory to therapy and addition of azathioprine or methotrexate has a corticosteroid-sparing effect and increases duration of remission. Controlled ileal release budesonide (9 mg daily) induces clinical remission in 60-70% of patients with Crohn's ileitis or right-sided colitis, and continued budesonide treatment has a finite effect on the duration of remission. The efficacy of mesalazine in active Crohn's disease is limited and high doses are required (4000 mg/day). The role of mesalazine in Crohn's disease in remission is disputed, and there is no evidence of a corticosteroid-sparing effect.  相似文献   
20.
A method is proposed for analyzing the change in the relaxation parameters of polymers during deformation by the method of repeated drawing with holding at each step until relaxation occurs. It is shown that the stress relaxation curves for polypropylene fibre can be described by two Maxwellian components with variable parameters. The characteristics of the change in the relaxation parameters of polypropylene fibre during deformation are determined.  相似文献   
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