作物废料转变为运输用燃料的途径

生物燃料是指通过生物资源生产的燃料乙醇和生物柴油,可以替代由石油制取的汽油和柴油,是可再生能源开发利用的重要方向.而由木头、草或植物的不能吃的部分生产出的燃料称为"纤维质生物燃料"."纤维质生物燃料"来自于被废弃的植物部分,无需以种植方式来获得,因此,不会占用人类耕地,可以轻易地获得,十分的环保.     

Subacute atropine toxicity in a pygmy sperm whale, Kogia breviceps.

Atropine, an anticholinergic agent commonly used in human and veterinary medicine, is reported to cause toxicity associated with its antimuscarinic action. A juvenile pygmy sperm whale, Kogia breviceps, was treated with atropine in an attempt to relieve symptoms similar to pyloric stenosis, as has been used in humans. Two doses of 0.01 mg/kg were given i.m., 12 hr apart, followed by three doses of 0.005 mg/kg i.m. s.i.d. over the next 3 days. Symptoms associated with atropine toxicity developed gradually and included hyperexcitability, a generalized ascending paralysis of body musculature, shallow, rapid respiration, vomiting, aspiration of seawater, and pulmonary edema. Treatment with physostigmine salicylate (two doses of 2 mg i.m., I hr apart) was effective in counteracting the paralysis, as well as other symptoms, beginning in as little as 17 min after the first dose, and the whale was back to swimming on its own after 8 hr. All overt symptoms of atropine toxicity were gone in about 24 hr, but there were other possible sequella that lasted much longer.     

Steady-state plasma concentrations of itraconazole after oral administration in Kemp's ridley sea turtles, Lepidochelys kempi.

Pharmacokinetic studies of antifungal agents in reptiles are uncommon. Itraconazole, which has been used prophylactically in juvenile sea turtles suffering from hypothermia (cold stunning) on a regular basis, was evaluated for steady-state plasma concentrations. Five Kemp's ridley sea turtles (Lepidochelys kempi) receiving itraconazole at several dosages in a rehabilitation program had blood collected within 24 hr to estimate dosing frequency. Subsequently, serial blood samples of Kemp's ridley sea turtles that were given itraconazole at several dosages for 30 days to treat cold stunning were collected at various intervals to evaluate itraconazole plasma concentrations. Tissue samples were collected from one Kemp's ridley that died during rehabilitation. Plasma concentrations of itraconazole (and of hydroxyitraconazole [OH-ITRA], one of its major bioactive metabolites) were determined using a modified, validated reverse-phase high-performance liquid chromatography technique. Itraconazole concentrations in tissues were determined by bioassay to be far greater than the plasma concentrations measured in any of the turtles. At a 15-mg/kg dosage, the half-life (t1/2) was 75 hr for itraconazole and 55 hr for OH-ITRA. All dosages produced adequate concentrations in some turtles, but consistent therapeutic concentrations were produced only at 15 mg/kg q72hr and 5 mg/kg s.i.d., with the latter producing the highest plasma concentrations.     

Electrocardiography‐gated cardiac CT angiography can differentiate brachycephalic dogs with and without pulmonary valve stenosis and findings differ from transthoracic echocardiography

Pulmonary valve stenosis (PS) is one of the most commonly diagnosed congenital heart defects in dogs. Currently, transthoracic echocardiography (TTE) is the standard modality used to evaluate PS. Image acquisition by TTE can be challenging in some brachycephalic breeds of dogs. The use of echocardiographic‐gated CT angiography (ECG‐gated CTA) in veterinary medicine is limited. This retrospective method comparison study investigated right and left ventricular outflow diameters by sedated ECG‐gated CTA and unsedated TTE in 14 brachycephalic dogs with PS and 12 brachycephalic dogs without PS. Measurements of ventricular outflow structures were made in early systole and end diastole for both modalities and then compared for significance between systolic and diastolic phases, as well as between the two modalities. Ratios of the pulmonary trunk diameter to the aorta at different locations (aortic valve, aortic annulus, and ascending aorta) and in different planes (transverse, sagittal) were compared between dogs with PS and without PS, as well as within dogs, by both TTE and ECG‐gated CTA. Transthoracic echocardiography and ECG‐gated CTA both detected significantly greater pulmonary trunk to aorta ratios in dogs with PS at all aortic locations (P < 0.05). Pulmonary valve to aortic valve ratios were significantly smaller in dogs with PS (P < 0.05). Pulmonary trunk to aorta and pulmonary valve to aorta ratios were achieved with good anatomic detail using ECG‐gated CTA. Ratios of the pulmonary trunk and pulmonary valve relative to the aorta may be useful to evaluate for PS using a modality that is underutilized for cardiac assessment.     

国际蚜虫基因组联盟成功绘制出蚜虫基因组图谱

蚜虫是以植物的韧皮部流体为食物的小型昆虫,以群体形式吸取植物的养分并传播植物病毒,给全世界农作物带来巨大灾害.蚜虫对环境条件的变化适应性强,不断在单性繁殖和有性繁殖之间切换产生出各种表观形态.因其非常奇特的生物学特性成为基础生物学研究重要的模式生物.     

Use of human recombinant erythropoietin for the treatment of nonregenerative anemia in a rough-toothed dolphin (Steno bredanensis).

Erythropoietin, a glycoprotein growth hormone that is produced primarily in the kidneys, promotes mitosis and survival of erythroid progenitors. The recent synthesis of the human form of the hormone by recombinant technology has provided a new therapeutic option, which is being used in both human and veterinary medicine for treatment of various anemias. A mature male rough-toothed dolphin, Steno bredanensis, was treated with human recombinant erythropoietin in an attempt to resolve a nonregenerative anemia. Two i.m. injections 48 hr apart were associated with an almost immediate increase in circulating immature reticulocytes, total reticulocytes, and nucleated erythrocytes. Over the next several weeks, the hematocrit, hemoglobin, and erythrocyte counts returned to normal, and the animal was subsequently released back into the wild. Endogenous erythropoietin concentrations were determined for this animal as well as three other conspecifics by an enzyme-linked immunosorbent assay for human erythropoietin. These measurements showed circulating erythropoietin concentrations (5-20+ mU/ml) similar to those of most other mammals. This study suggests that human recombinant erythropoietin can be safely and effectively used in this species and may have applicability to other cetacean species for the treatment of nonregenerative anemia. Caution should be exercised during long-term use because production of antibodies to human recombinant and endogenous erythropoietin may lead to potentially serious side effects.     

科学家研究发现形成哺乳动物身上斑点条纹基因

科学家首次发现老虎身上的条纹、美洲豹身上的斑点和家猫身上的纹理至少和3种基因有关.该研究发表在2010年1月(相似文献   

The effects of protein level on cytokines and chemokines in the uterine environment of beef heifers during development

The development of replacement heifers is crucial for breeding success and herd efficiency. Nutritional management can affect not only reproductive development but also the inflammatory status of the uterine environment, which may impact reproductive functions such as pregnancy establishment and development. The study herein evaluated the concentration of cytokines and chemokines in the uterus of heifers supplemented with different levels of protein. Angus heifers (n = 60) were blocked by body weight (BW) and randomly assigned to 1 of 3 treatments based on protein supplementation level: control of 10% crude protein (CON), 20% crude protein (P20), or 40% crude protein (P40). BW, body condition score, and blood samples were taken every 2 wk for 140 d to monitor development. Uterine flushes were performed monthly and concentrations of cytokines (IL-1α, IL-1β, TNF-α, IFN-γ, IL-10, VEGF-α, IL-17A, and IL-36RA) and chemokines (IL-8, MCP-1, MIP-1α, and MIP-1β) were quantified via ELISA multiplex. To test if there were mean differences in cytokines between the treatment groups or over time, PROC GLIMMIX (SAS v 9.4) was utilized. Concentrations of all cytokines and chemokines, except IL-1α, changed throughout heifer development (P < 0.05). Heifers in the P40 treatment group displayed reduced concentrations of MCP-1 (P = 0.007) and tended to have decreased concentrations of IFN-γ (P = 0.06). Cytokine IL-36RA tended (P = 0.06) to be affected by protein level, with the lowest concentrations observed in CON heifers. Most cytokines and chemokines increased following the initial month of supplementation (P < 0.05). The increase in concentrations after 1 mo may indicate an adaptive response in the uterus to diet change. Cytokines and chemokines fluctuated due to physiological changes occurring during development. Further research is needed to determine the influence of nutrition on uterine inflammation and long-term impacts on reproductive function.