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Objective： This study aimed to provide the basis of quantity traceability for the analysis of amoxicillin residues in milk. At the same time, it can also provide quantity standards for ensuring the effective implementation of amoxicillin monitoring in milk and combating the abuse of amoxicillin in the country and regions. Methods： Two healthy middle-class dairy cows were injected with amoxicillin intramuscularly. After the natural metabolism of the drug for a period of time, the milk containing the target drug amoxicillin was collected and made into milk matrix reference material containing amoxicillin by vacuum freeze-drying technology. The uniformity test, stability test, fixed value and uncertainty evaluation of the prepared milk lyophilized powder matrix reference material were carried out. Results： In the uniformity test, the F value obtained is 0.05, The results showed that the preparation of the standard milk powder was homogeneous; In the stability test, the short-term stability test （25, 4, -20 ℃; 2 weeks） and long-term stability test （4, -20 ℃; 6 months） showed good stability;The reference materials were jointly calibrated by 8 laboratories, and the final calibration result was 4.05 μg/kg, the total uncertainty being 0.2 μg/kg. Conclusion： The prepared amoxicillin matrix reference material in milk freeze-dried powder has good uniformity and stability, which can be used as a carrier to trace the amount of amoxicillin in milk, and can be widely used in the methodology verification and quality control of amoxicillin detection in milk.

Stainless steel is widely used in many fields because of its excellent corrosion resistance, electrical and thermal conductivity and machining properties.In order to avoid the corrosion damage of stainless steel in use, the preparation of corrosion resistant coating on surface of substrate is the main protective measure.Firstly, combined with the research status of corrosion resistant coatings prepared by electrodeposition on surface of stainless steel in recent years, the research progress of single-layer corrosion resistant coating, multi-layer corrosion resistant coating and dopant-modified composite film on surface of stainless steel were summarized in this paper.On this basis, three main protection mechanisms of the corrosion resistant coating on the stainless steel substrate were summarized from one of the perspective of the protection mode of the coating on the substrate: conventional protection mechanism of single-layer coating, synergy mechanism of multi-layer coating and protection mechanism of second phase structure optimization.Also, the action modes and differences of these three mechanisms were compared.Finally, the research direction of corrosion resistant coating prepared by electrodeposition on surface of stainless steel was prospected, with the purpose to provide a useful reference for the research and development of high-quality corrosion-resistant coating on surface of stainless steel.

The article offers information on the effect of nucleic acid on immunization and antioxdative activity of infectious bursal disease (IBDV) infected chicken in China. It states that blood samples are collected for the detection of phagocytosis ability of leukocyte, transformation rate of T cell and glutathione peroxidase. It emphasizes that the supplemented different dosage of nucleic acid increases the percent coversion of T lymphocyte and T cell numbers.

Abnormal mechanical load, as seen in hypertension, is found to induce heart cell apoptosis, yet the signaling link between cell stretch and apoptotic pathways is not known. Using an in vitro stretch model mimicking diastolic pressure stress, here we show that Ca2+ signaling participates essentially in the early stage of stretch-induced apoptosis. In neonatal rat cardiomyocytes, the moderate 20% stretch resulted in tonic elevation of intracellular free Ca2+ ([Ca2+]i). Buffering [Ca2+]i by EGTA-AM, suppressing ryanodine-sensitive Ca2+ release, and blocking L-type Ca2+ channels all prevented the stretch-induced apoptosis as assessed by phosphatidylserine exposure and nuclear fragmentation. Notably, Ca2+ suppression also prevented known stretch-activated apoptotic events, including caspase-3/-9 activation, mitochondrial membrane potential corruption, and reactive oxygen species production, suggesting that Ca2+ signaling is the upstream of these events. Since [Ca2+]i did not change without activating mechanosensitive Ca2+ entry, we conclude that stretch-induced Ca2+ entry, via the Ca2+-induced Ca2+ release mechanism, plays an important role in initiating apoptotic signaling during mechanical stress. [Copyright &y& Elsevier]

Objective: To study the clinical value and operation skills of nasal endoscopy-assisted bulboprostatic anastomosis in the treatment of posterior urethral stricture., Methods: Between January 2012 and November 2014, we performed nasal endoscopy-assisted bulboprostatic anastomosis for 12 male patients with posterior urethral stricture. We recorded the operation time, blood loss, exposure of operation visual field, and success rate of anastomosis and summarized the operation skills., Results: Eight of the patients experienced first-stage recovery. Two underwent a urethral dilation at 3 months postoperatively, 1 received 10 urethral dilations within 5 months after surgery, and 1 underwent internal urethrotomy after failure in urethral dilation, but all the 4 cases were cured., Conclusion: Nasal endoscopy can significantly improve the operation field exposure, elevate the precision, reduce the difficulty, and enhance the efficiency of bulboprostatic anastomosis in the treatment of posterior urethral stricture.

Aim: To assess the blockade by CPU 86017 on the L-type calcium channels in the myocardium and on the Ca(2+)-related contractions of vascular smooth muscle., Methods: The whole-cell patch-clamp was applied to investigate the blocking effect of CPU 86017 on the L-type calcium current in isolated guinea pig myocytes and contractions by KCl or phenylephrine (Phe) of the isolated rat tail arteries were measured., Results: Suppression of the L-type current of the isolated myocytes by CPU 86017 was moderate, in time- and concentration-dependent manner and with no influence on the activation and inactivation curves. The IC(50) was 11.5 micromol/L. Suppressive effect of CPU 86017 on vaso-contractions induced by KCl 100 mmol/L, phenylephrine 1 micromol/L in KH solution (phase 1), Ca(2+) free KH solution ( phase 2), and by addition of CaCl(2) into Ca(2+)-free KH solution (phase 3) were observed. The IC(50) to suppress vaso-contractions by calcium entry via the receptor operated channel (ROC) and voltage-dependent channel (VDC) was 0.324 micromol/L and 16.3 micromol/L, respectively. The relative potency of CPU 86017 to suppress vascular tone by Ca(2+) entry through ROC and VDC is 1/187 of prazosin and 1/37 of verapamil, respectively., Conclusion: The blocking effects of CPU 86017 on the L-type calcium channel of myocardium and vessel are moderate and non-selective. CPU 86017 is approximately 50 times more potent in inhibiting ROC than VDC.

Aim: To study the effect of puerarin (Pue) on Na+ channel in rat ventricular myocytes., Methods: Whole-cell patch-clamp technique was applied on isolated cardiomyocytes from rats., Results: Pue inhibited cardiac INa in a positive rate-dependent and dose-dependent manner, with an IC(50) of 349 micromol/L. The kinetics of blockage of cardiac sodium channel by Pue resembled the ClassIa/Ic of antiarrhythmic agents. Pue 300 micromol/L did not alter the shape of the I-V curve of INa, but markedly shifted the steady-state inactivation curve of INa towards more negative potential by 15.9 mV, and postponed the recovery of INa inactivation state from (21.9+/-1.6) ms to (54.4+/-3.4) ms (P<0.01). It demonstrated that the steady state of inactivation was affected by Pue significantly., Conclusion: Pue protected ventricular myocytes against cardiac damage and arrhythmias by inhibiting recovery from inactivation of cardiac Na+ channels.

Aim: To study the blockade of paeoniflorin (Pae) on I(Na) in the acutely isolated hippocampus neurons of mice., Methods: The whole-cell patch clamp technique was used., Results: Pae inhibited I(Na) in frequency-dependent and concentration-dependent manners, with an IC50 of 271 micromol/L. Pae 0.3 mmol/L shifted the activation potential of the maximal I(Na) from -40 mV to -30 mV, shifted the steady-state activation and inactivation curves toward more positive and negative potentials by 10.8 mV, and 18.2 mV, respectively, and postponed the recovery of I(Na) inactivation state from (4.2+/-0.7) ms to (9.8+/-1.2) ms., Conclusion: Pae inhibited I(Na) in mouse hippocampus neurons.

This paper reports the construction of the database for Genomic Polymorphism of Chinese Ethnic Groups (GPCEG). GPCEG contains denomination and basic information of Chinese 56 ethnic groups, with introduction of their in geographic distribution, population quantity, spoken and written language, religious belief and physical characteristics. GPCEG collects the data of genomic polymorphism, cell lines, reference and links of other international related databases. The visualization, query and update system were also available. GPCEG laid the foundations of establishing a national database with Chinese characteristics.

The iron response element (IRE) is a highly conserved RNA stem loop structure. It is the binding site of iron regulatory protein (IRP). IRP binding to IRE is regulated by cellular iron. When cells are derived of iron, IRP binds IRE. If IRE is located at 5'UTR, IRP binding will inhibit translation initiation, else if IRE is at 3'UTR, IRP binding will stabilize mRNA and prevent it from degradation. So far all known IREs have C at the 1 position and G at the 5 position of the loop (C1G5 type). In vitro studies suggest that the U1A5 type IRE, which has U and A at the 1 and 5 loop position respectively, binds well to IRP. However, U1A5 type's in vivo existence is still elusive. IRE-IRP binding is involved in the regulation of iron metabolism, oxidative stress and possibly aging. Here we use an improved computation method performing a comprehensive search of IRE in human and mouse genes. We try to catalog potential human and mouse IRE containing genes, at the same time identify potential U1A5 IREs.

Females ofMyelois cribrella contain about 20 ng/gland of the primary sex pheromone components (Z)-9-tetradecenyl acetate, (9Z,12E)-9,12-tetradecadienyl acetate, and (Z)-11-hexadecenyl acetate in proportions of 4∶11∶5, respectively. These physiologically active components are accompanied by a number of related compounds such as (Z)-9-tetradecen-1-ol, hexadecyl acetate, (9Z,12E)-9,12-tetradecadien-1-ol, (Z)-11-hexadecen-1-ol, octadecyl acetate, octadecan-1-ol, and eicosyl and docosyl acetates. Octadecyl acetate, the most abundant component, represents about 42 ng/female moth; however, no physiological activity could be attributed to it. In field tests, a trap baited with a 1-mg mixture of (Z)-9-tetradecenyl acetate, (9Z,12E)-9,12-tetradecadienyl acetate, and (Z)-11-hexadecenyl acetate in a ratio of 1∶2∶1 caught more male moths than three live female moths.