屠宰猪关节液中红斑丹毒丝菌的分离与鉴定

检查了106头屠宰猪的关节液,从25头分离到红斑丹毒丝菌,阳性率为23.6％。对全部分离菌进行了系统鉴定,包括形态、染色、培养特性、生化特性、血清学反应、致病力、对抗菌剂的敏感性和血浆凝固酶试验等。结果表明,分离菌系统鉴定的各项指标均较复杂,72.0％的菌株对小鼠有致病力,但多数菌株的致病力较弱。     

Pharmacokinetics and ex vivo pharmacodynamics of cefquinome in porcine serum and tissue cage fluids

A tissue cage (TC) model was used to evaluate the pharmacokinetics and ex vivo pharmacodynamics of cefquinome after intravenous (IV) and intramuscular (IM) administration to piglets at 2 mg/kg bodyweight. The mean values of area under the concentration–time curve (AUC) were 21.28 (IV) and 21.37 (IM) μg h/mL for serum, and 17.40 (IV) and 16.57 (IM) μg h/mL for TC fluid (TCF), respectively. Values of maximum concentration (C_max) were 6.15 μg/mL (serum) and 1.15 μg/mL (TCF) after IM administration. The elimination half-lives (t_1/2β) in TCF (10.63 h IV and 11.81 h IM) were significantly higher than those in serum (2.33 h IV and 2.30 h IM) (P < 0.05). The values of AUC_TCF/AUC_serum (%) after IV and IM administration were 82.4% and 80.7%, respectively.The ex vivo time-kill curves were established for serum and TCF samples using Escherichia coli ATCC 25922. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration values of cefquinome against E. coli were 0.030 and 0.060 μg/mL in Mueller–Hinton broth, and 0.032 and 0.064 μg/mL in both serum and TCF, respectively. The ex vivo growth inhibition data of TCF after IM administration were fitted to the sigmoid E_max model; AUC_24h/MIC was 35.01 h for bactericidal activity and 44.28 h for virtual eradication, respectively. The findings from this study suggest that cefquinome may be therapeutically effective in diseases of pigs caused by E. coli when used at a dose rate of 1.33 mg/kg administered every 24 h for organisms with MIC₉₀ ⩽ 0.50 μg/mL.     

不同宿主源棘球蚴包囊液抗原的SDS—PAGE分析

本文利用ＳＤＳ－ＰＡＧＥ对不同宿主源棘球蚴囊液抗原的多肽组成进行了分析和比较,旨在为免疫诊断抗原的分离、鉴定和纯化奠定基础,为细粒棘球绦虫种内变异和株的鉴定提供参考指标。结果表明,在还原条件下,绵羊棘球蚴囊液抗原共有多肽带１９条,其中６６和５９ＫＤ多肽带为主带,４０、３４．５、３３、２４．５和１４ＫＤ多肽带次之。牛源囊液抗原共有多肽带１２条,６６和５９ＫＤ多肽带也为主带,２４．５ＫＤ多肽带次之。人源囊液抗原共有多肽带１３条,６６、４０、２０．５和１４ＫＤ多肽带为主带,５９ＫＤ多肽带近于缺乏,分子量在５９和２４ＫＤ之间的带明显偏少,而７１、６９、６８和２０．５ＫＤ多肽带为自身特有。３种不同宿主源棘球蚴囊液抗原其多肽组成均很复杂,羊、牛源囊液抗原的ＳＤＳ－ＰＡＧＥ图谱较相似,而人源与此差异明显。初步认为绵羊和牛源囊液抗原在免疫诊断中具有可替代性。     

Accuracy of Potassium Supplementation of Fluids Administered Intravenously

Background

Potassium (K⁺) supplementation of isotonic crystalloid fluids in daily fluid therapy is commonly performed, yet its accuracy in veterinary medicine is undetermined.

Objective

To investigate the accuracy of K⁺ supplementation in isotonic crystalloid fluids.

Animals

None.

Methods

Observational study. 210 bags of fluid supplemented with KCl being administered to hospitalized dogs and cats intravenously (IV) were sampled over a 3‐month period. Measured K⁺ concentration ([K⁺]) was compared to the intended [K⁺] of the bag. In a second experiment, 60 stock fluid bags were supplemented to achieve a concentration of 20 mmol/L K⁺, mixed well and [K⁺] was measured. In another 12 bags of 0.9% NaCl, K⁺ was added without mixing the bag, and [K⁺] of the delivered fluid was measured at regular time points during constant rate infusion.

Results

The measured [K⁺] was significantly higher than intended [K⁺] (mean difference 9.0 mmol/L, range 6.5 to >280 mmol/L, P < .0001). In 28% of clinical samples measured [K⁺] was ≥5 mmol/L different than intended [K⁺]. With adequate mixing, K⁺ supplementation of fluids can be accurate with the mean difference between measured and intended [K⁺] of 0.7 (95% CI −0.32 to 1.7) mmol/L. When not mixed, K⁺ supplementation of 20 mmol/L can lead to very high [K⁺] of delivered fluid (up to 1410 mmol/L).

Conclusions and Clinical Importance

Inadequate mixing following K⁺ supplementation of fluid bags can lead to potentially life threatening IV infused [K⁺]. Standard protocols for K⁺ supplementation should be established to ensure adequate mixing.     

Changes in colloid osmotic pressure as a function of anesthesia and surgery in the presence and absence of isotonic fluid administration in dogs

Objective  To determine how a combination of anesthetic drugs; including pre-medication, induction agents and inhalational agents; affect colloid osmotic pressure (COP) in the presence and absence of isotonic fluid administration. Secondarily, to determine if changes in total plasma protein (TPP) correlate with COP in anesthetized patients.
Study Design  Prospective, randomized clinical study.
Animals  Ten female dogs, 4 months to 4 years of age and >8 kg undergoing elective ovariohysterectomy.
Methods  All dogs were anesthetized in a similar fashion. After induction, five dogs received lactated ringer's solution (LRS) at 10 mL kg⁻¹ hour⁻¹ and five dogs received no fluid therapy during anesthesia. Blood samples were collected prior to pre-medication, prior to induction, immediately post-induction/prior to the inhalational agent, 30 minutes post-induction, at the time of recovery and 45 minutes post-discontinuation of inhalant. TPP and COP were measured from each sample.
Results  Administration of fluids resulted in a decrease in COP and TPP over time that did not return to baseline by 45 minutes after recovery. Anesthesia without the administration of fluids also resulted in a significant decrease in COP over time, that was rebounding by recovery (but still significantly less than baseline). TPP had variable correlation with COP at different time points with or without fluid administration.
Conclusions and clinical relevance  Anesthetic drugs alter COP similarly in the presence and absence of isotonic fluids. These changes in COP did not have a simple relationship to TPP and so the latter could not be used to predict COP in this patient population.     

鸡胚发育过程中胚胎液中几种游离氨基酸的动态变化

本实验旨在研究鸡胚发育过程中尿囊液和羊水中天冬氨酸、谷氨酸、精氨酸和亮氨酸浓度的动态变化。选用72枚6胚龄的三黄鸡鸡胚,按重量相近原则分为6组,每组12个重复,分别在孵化第7、8、11、13、14、18天采集尿囊液和羊水,并利用高效液相色谱法分析其氨基酸浓度。结果表明:尿囊液中,除8胚龄外,其他各胚龄精氨酸浓度均高于另外3种氨基酸(P<0.05),13胚龄精氨酸浓度显著低于其他胚龄(P<0.05),而18胚龄显则著高于其他胚龄(P<0.05)。羊水中,各胚龄精氨酸浓度均高于其他3种氨基酸;除11胚龄外,13胚龄精氨酸浓度显著高于其他胚龄(P<0.05);7胚龄天门冬氨酸浓度显著高于13、14、18胚龄(P<0.05);但18胚龄谷氨酸及亮氨酸浓度则显著升高(P<0.05)。以上结果说明,在尿囊液及羊水中,所测4种氨基酸浓度变化不尽相同,但总体精氨酸含量最丰富,这可能与鸡胚发育的营养与代谢有关。     

High‐sensitivity detection of short‐chain fatty acids in porcine ileal,cecal, portal and abdominal blood by gas chromatography‐mass spectrometry

Short‐chain fatty acids (SCFA), such as acetate, propionate and n‐butyrate, are the main end‐products of fermentation in the large intestine. SCFA are rapidly absorbed from the large intestinal mucosa to provide energy to the host. In this study, high‐sensitivity detection of SCFA was demonstrated in blood using the gas chromatometry with mass spectrometry (GC‐MS). Few studies have measured SCFA in porcine blood. Therefore, SCFA concentrations in the ileal (IV), cecal (CV), portal (PV) and abdominal (AV) vein blood, urine (Ur) and saliva (Sa) were measured by GC‐MS. All body fluids were collected from four 5‐month‐old pigs. Cecal (CD) and ileal (ID) digesta, and cecal (CM) and ileal (IM) mucosa were also collected and their corresponding SCFA concentrations were measured using ion‐exclusion high‐performance liquid chromatography. GC‐MS analyses were successful to determine the SCFA concentrations in the porcine body fluids. n‐Butyrate concentration was surprisingly high in CV and its proportion remained higher in CV than that in CD and CM. Acetate showed a constantly high proportion in all porcine body fluids. Propionate was detected at a relatively high proportion in CV, IV and PV, but was low in AV.     

苜蓿茎秆的拉伸力学特性试验

本研究对低含水率的苜蓿茎秆不同部位进行了拉伸力学特性试验。结果表明,同一植株不同位置的拉断载荷从顶部到根部呈明显增加趋势,一般根部的拉断载荷是顶部的2～4倍;抗拉强度变化趋势不明显;苜蓿茎秆试样上部、中部和下部的平均直径分别是1.72mm、2.03mm和2.21mm,平均壁厚分别是0.18mm、0.22mm和0.31mm,平均抗拉强度分别为77.06594MPa、96.24907MPa和75.27600MPa,平均载荷分别是59.50628N、105.68330N和121.33230N;验证分析表明,苜蓿茎秆中部和下部的抗拉强度与截面积的相关性较好,上部茎秆的相关性稍差。     

闲散未成年人犯罪的原因及对策

闲散未成年人是指达到法定入学年龄但没入学,或者结束某一阶段学业后并未升学或就业的未成年人。家庭教养的不当与缺失,学校应试教育的缺陷与失误,社会不良因素的影响是闲散未成年人犯罪的主要原因。要有效预防闲散未成年人犯罪就必须依靠和发挥整个社会的力量,形成齐抓共管的局面,把影响未成年人基本生存、健康成长的不利因素减少到最低限度,为未成年人营造一个良好的生存、成长与发展的空间。