体层低张静脉尿路造影术

用体层低张静脉尿路造影技术，对１１０例有泌尿系统疾病患者作了检查，成功率为９８％。本法的优点不但有效地解决了传统操作中因腹部加压不当造影易失败和给病人带来的痛苦，且对肾脏，膀胱像显示加清晰。本法对提高泌尿系统疾病的诊断水平有重要价值。     

Effect of intravenous propofol and remifentanil on heart rate, blood pressure and nociceptive response in acepromazine premedicated dogs

ObjectiveTo investigate the cardiorespiratory, nociceptive and endocrine effects of the combination of propofol and remifentanil, in dogs sedated with acepromazine.Study designProspective randomized, blinded, cross-over experimental trial.AnimalsTwelve healthy adult female cross-breed dogs, mean weight 18.4 ± 2.3 kg.MethodsDogs were sedated with intravenous (IV) acepromazine (0.05 mg kg^?1) followed by induction of anesthesia with IV propofol (5 mg kg^?1). Anesthesia was maintained with IV propofol (0.2 mg kg^?1 minute^?1) and remifentanil, infused as follows: R1, 0.125 μg kg^?1 minute^?1; R2, 0.25 μg kg^?1 minute^?1; and R3, 0.5 μg kg^?1 minute^?1. The same dogs were administered each dose of remifentanil at 1-week intervals. Heart rate (HR), mean arterial pressure (MAP), respiratory rate (f_R), end tidal CO₂ (Pe′CO₂), arterial hemoglobin O₂ saturation, blood gases, and rectal temperature were measured before induction, and 5, 15, 30, 45, 60, 75, 90, and 120 minutes after beginning the infusion. Nociceptive response was investigated by electrical stimulus (50 V, 5 Hz and 10 ms). Blood samples were collected for plasma cortisol measurements. Statistical analysis was performed by anova (p < 0.05).ResultsIn all treatments, HR decreased during anesthesia with increasing doses of remifentanil, and increased significantly immediately after the end of infusion. MAP remained stable during anesthesia (72–98 mmHg). Antinociception was proportional to the remifentanil infusion dose, and was considered satisfactory only with R2 and R3. Plasma cortisol concentration decreased during anesthesia in all treatments. Recovery was smooth and fast in all dogs.Conclusions and clinical relevanceInfusion of 0.25–0.5 μg kg^?1 minute^?1 remifentanil combined with 0.2 mg kg^?1 minute^?1 propofol produced little effect on arterial blood pressure and led to a good recovery. The analgesia produced was sufficient to control the nociceptive response applied by electrical stimulation, suggesting that it may be appropriate for performing surgery.     

Hormone interactions confer specific proliferative and histomorphogenic responses in the porcine mammary gland

Mammary gland growth and morphogenesis are regulated by interactions between hormones as much as by their individual actions. The effect of these interactions on the mammary gland phenotype in species other than rodents is relatively undefined. We investigated the individual and combined effects of estrogen (E), progestin (P), and prolactin (PRL) on mammary gland development in gilts. Pigs were shown to have a ductal-lobular parenchyma that underwent hormone-stimulated progression of terminal ductal lobular unit (TDLU) morphogenesis similar to that in the human breast. Ovariectomy plus hypoprolactinemia abolished mammary gland growth. Estrogen alone stimulated mammary epithelial cell proliferation, terminal bud formation, and the progression of TDLU1 structures to a TDLU2 morphotype. Maximal epithelial cell proliferation, DNA content, parenchymal area, and morphological development of the porcine mammary gland were realized following treatment with E + PRL or E + P + PRL. In contrast, P alone did not promote epithelial cell proliferation, TDLU type progression, mammary gland growth, or morphogenesis. These data indicate that interactions between E and PRL are the main determinants of growth and morphogenesis in the porcine mammary gland.     

贵州黑山羊胚胎移植手术不同麻醉方法比较

为了筛选适合于贵州黑山羊胚胎移植手术的麻醉方法,试验以贵州黑山羊为试验动物,比较了速眠新Ⅱ注射液2种麻醉方法（肌肉麻醉和静脉麻醉）对山羊生理指标,麻醉山羊的诱导期、麻醉期、苏醒期,麻醉苏醒后山羊的采食、反刍及精神状况的影响。结果表明：2种麻醉方法下,麻醉效果优、良的山羊数量和生理指标无明显差异;速眠新Ⅱ注射液静脉注射麻醉时,山羊的诱导期、麻醉期和苏醒期均较短,在苏醒后0.5 h,90.0%的山羊可以采食,83.3%的山羊可以反刍,93.3%的山羊精神状况良好;苏醒后1 h基本上全部可以恢复正常;采用静脉注射麻醉山羊进行胚胎移植手术,速眠新Ⅱ注射液用药剂量小,且安全、有效,明显优于肌肉注射。     

Lack of gender effect on the pharmacokinetics and pharmacodynamics of dexamethasone in the camel after intravenous administration

The pharmacokinetics and pharmacodynamics of dexamethasone were studied in six male and six female camels after a single intravenous dose (0.05 mgkg(-1) body weight) of dexamethasone. The pharmacokinetic parameters of the two-compartment pharmacokinetic model for female and male camels, respectively (mean+/-SEM) were as follows: terminal elimination half-lives were 8.02+/-1.15 and 7.33+/-0.80 h, total body clearances were 95.5+/-16.0 and 124.5+/-11.9 ml h(-1) per kg, volumes of distribution at steady state were 0.72+/-0.08 and 0.87+/-0.14 litre kg(-1), and the volumes of the central compartment were 0.12+/-0.02 and 0.17+/-0.02 litre kg(-1). There was no significant difference in any pharmacokinetic parameter between female and male camels. Pharmacodynamic effects were evaluated by measuring endogenous plasma cortisol, circulating lymphocytes and neutrophils numbers and were analysed using indirect pharmacokinetic/pharmacodynamic models. The estimated IC50 of dexamethasone for cortisol and lymphocytes for female and male camels were 3.74+/-0.99 and 2.28+/-1.09 and 2.63+/-0.71 and 2.41+/-0.79 ng ml(-1), respectively. The EC50 for neutrophils for female and male camels were 24.5+/-5.83 and 20.2+/-3.82 ng ml(-1), respectively. There was no significant difference in any pharmacodynamic parameter between female and male camels. Dexamethasone in urine could be detected for 4-5 days by enzyme-linked immunosorbent assay and for 3-4 days by liquid chromatography/mass spectrometry after an intravenous dose of 0.05 mg kg(-1) body weight.     

Pharmacokinetics of single-dose intravenous levetiracetam administration in normal dogs

Objective: To determine plasma pharmacokinetics of levetiracetam after a single intravenous dose (60 mg/kg) in normal dogs using a high‐performance liquid chromatography assay validated for canine plasma. Design: Pharmacokinetic study. Setting: A university‐based canine research facility. Animals: Six healthy adult dogs. Interventions: Intravenous drug administration, multiple blood sample procurement. Measurements and main results: There were no obvious adverse effects associated with the intravenous (IV) bolus administration of levetiracetam in any of the dogs. Plasma levetiracetam concentrations remained above or within the reported therapeutic range for humans (5–45 μg/mL) for all dogs, for all time periods evaluated. Mean and median (in parentheses) values for pharmacokinetic parameters included the following: maximum plasma concentration, 254 μg/mL (254 μg/mL); half‐life, 4.0 hours (4.0 hours); volume of distribution at steady state, 0.48 L/kg (0.48 L/kg); clearance, 1.4 mL/kg/min (1.5 mL/kg/min); and median residence time, 6.0 hours (6.0 hours). Conclusions: In normal dogs, a 60 mg/kg IV bolus dose of levetiracetam is well tolerated and achieves plasma drug concentrations within or above the therapeutic range reported for humans for at least 8 hours after administration. Based on the favorable pharmacokinetics and tolerability demonstrated for IV levetiracetam in this study, in addition to previously demonstrated efficacy of oral levetiracetam, IV levetiracetam may be a useful treatment option for emergency management of canine seizure activity.     

The pharmacokinetics of moxidectin following intravenous and topical administration to swine

The pharmacokinetic parameters of moxidectin (MXD) after intravenous and pour‐on (topical) administration were studied in sixteen pigs at a single dose of 1.25 and 2.5 mg/kg BW (body weight), respectively. Blood samples were collected at pretreatment time (0 hr) over 40 days. The plasma kinetics were analyzed by WinNonlin 6.3 software through a noncompartmental model. For intravenous administration (n = 8), the elimination half‐life (λ_Z), the apparent volume of distribution (V_z), and clearance (Cl) were 10.29 ± 1.90 days, 89.575 ± 29.856 L/kg, and 5.699 ± 2.374 L/kg, respectively. For pour‐on administration (n = 8), the maximum plasma drug concentration (C_max), time to maximum plasma concentration (T_max), and λ_Z were 7.49 ng/ml, 1.72, and 6.20 days, respectively. MXD had a considerably low absolute pour‐on bioavailability of 9.2%, but the mean residence time (MRT) for pour‐on administration 10.88 ± 1.75 days was longer than 8.99 ± 2.48 days for intravenous administration. These results showed that MXD was absorbed via skin rapidly and eliminated slowly. The obtained data might contribute to refine the dosage regime for topical MXD administration.