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31.
兔出血症是由兔出血症病毒引起的以呼吸系统出血、肝坏死、实质器官水肿、淤血及出血性变化为特征一种高度接触性传染病,具有潜伏期短、发病率和死亡率极高的特点。兔出血症病毒与大肠杆菌混合感染,大大增加了兔群的死亡率,给养兔业带来巨大的经济损失。本文以一起兔混合感染病例为题材,从发病情况、临床症状、剖检变化、实验室检查、防治等几个方面,做了详尽阐述。  相似文献   
32.
CASE DESCRIPTION: A healthy 6-year-old 28.5-kg (62.7-lb) spayed female Boxer undergoing surgical repair of a ruptured cranial cruciate ligament was inadvertently administered an overdose of morphine (1.3 mg/kg [0.59 mg/lb]) via subarachnoid injection. CLINICAL FINDINGS: 50 minutes after administration of the overdose, mild multifocal myoclonic contractions became apparent at the level of the tail; the contractions migrated cranially and progressively increased in intensity and frequency during completion of the surgery. TREATMENT AND OUTCOME: The myoclonic contractions were refractory to treatment with midazolam, naloxone, phenobarbital, and pentobarbital; only atracurium (0.1 mg/kg [0.045 mg/lb], IV) was effective in controlling the movements. The dog developed hypertension, dysphoria, hyperthermia, and hypercapnia. The dog remained anesthetized and ventilated mechanically; treatments included continuous rate IV infusions of propofol (1 mg/kg/h [0.45 mg/lb/h]), diazepam (0.25 mg/kg/h [0.11 mg/lb/h]), atracurium (0.1 to 0.3 mg/kg/h [0.045 to 0.14 mg/lb/h]), and naloxone (0.02 mg/kg/h [0.009 mg/lb/h]). Twenty-two hours after the overdose, the myoclonus was no longer present, and the dog was able to ventilate without mechanical assistance. The dog remained sedated until 60 hours after the overdose, at which time its mentation improved, including recognition of caregivers and response to voice commands. No neurologic abnormalities were detectable at discharge (approx 68 hours after the overdose) or at a recheck evaluation 1 week later. CLINICAL RELEVANCE: Although intrathecal administration of an overdose of morphine can be associated with major and potentially fatal complications, it is possible that affected dogs can completely recover with immediate treatment and extensive supportive care.  相似文献   
33.

Objective

To test the hypothesis that plasma propofol concentration (PPC) is associated with anesthetic effect in koi carp administered propofol by immersion.

Study design

Prospective study.

Animals

Twenty mature koi carp (mean ± standard deviation, 409.4 ± 83.7 g).

Methods

Fish were immersed in propofol (5 mg L–1). Physiological variables and induction and recovery times were recorded. In phase I, blood was sampled for PPC immediately following induction and at recovery. In phase II, following induction, fish were maintained with propofol (4 mg L–1) via a recirculating system for 20 minutes. Following established induction, blood was sampled at 1, 10 and 20 minutes. In phase III (n = 19), fish were anesthetized as in phase II with blood sampled nine times in a sparse sampling strategy. Simultaneously, a pharmacodynamics rubric was used to evaluate anesthetic depth. PPC was determined using high performance liquid chromatography with fluorescence detection. Following evaluation of normality, data were analyzed using paired t test or Spearman correlation test (significance was set at p < 0.05).

Results

In phase I, mean PPCs at induction (20.12 μg mL–1) and recovery (11.62 μg mL–1) were different (p < 0.001). In phase II, only mean PPCs at induction (17.92 μg mL–1) and 10 minutes (21.50 μg mL–1) were different (p = 0.013). In phase III, a correlation between PPCs and the pharmacodynamic rubric scores was found (p < 0.001, r = –0.93). There was no correlation between PPCs and recovery time (p = 0.057, r = 0.433). A two-compartment open model was chosen for the pharmacokinetic model. Absorption rate constant, elimination rate constant and intercompartmental rate constant were 0.48, 0.006 and 0.02 minute–1, respectively.

Conclusions and clinical relevance

Measurable PPCs were achieved in koi carp anesthetized with propofol by immersion. Anesthetic depth of fish was negatively correlated with PPCs, but recovery time was not.  相似文献   
34.
A double quantum dot device is a tunable two-level system for electronic energy states. A dc electron current was used to directly measure the rates for elastic and inelastic transitions between the two levels. For inelastic transitions, energy is exchanged with bosonic degrees of freedom in the environment. The inelastic transition rates are well described by the Einstein coefficients, relating absorption with stimulated and spontaneous emission. The most effectively coupled bosons in the specific environment of the semiconductor device used here were acoustic phonons. The experiments demonstrate the importance of vacuum fluctuations in the environment for quantum dot devices and potential design constraints for their use for preparing long-lived quantum states.  相似文献   
35.
The purpose of this study was to determine the pharmacokinetics of buprenorphine following intravenous (i.v.) and intramuscular (i.m.) administration in horses. Six horses received i.v. or i.m. buprenorphine (0.005 mg/kg) in a randomized, crossover design. Plasma samples were collected at predetermined times and horses were monitored for adverse reactions. Buprenorphine concentrations were measured using ultra-performance liquid chromatography with electrospray ionization mass spectrometry. Following i.v. administration, clearance was 7.97±5.16 mL/kg/min, and half-life (T(1/2)) was 3.58 h (harmonic mean). Volume of distribution was 3.01±1.69 L/kg. Following i.m. administration, maximum concentration (C(max)) was 1.74±0.09 ng/mL, which was significantly lower than the highest measured concentration (4.34±1.22 ng/mL) after i.v. administration (P<0.001). Time to C(max) was 0.9±0.69 h and T(1/2) was 4.24 h. Bioavailability was variable (51-88%). Several horses showed signs of excitement. Gut sounds were decreased 10±2.19 and 8.67±1.63 h in the i.v. and i.m. group, respectively. Buprenorphine has a moderate T(1/2) in the horse and was detected at concentrations expected to be therapeutic in other species after i.v. and i.m. administration of 0.005 mg/kg. Signs of excitement and gastrointestinal stasis may be noted.  相似文献   
36.
37.
Studies of the ground and excited states in semiconductor quantum dots containing 1 to 12 electrons showed that the quantum numbers of the states in the excitation spectra can be identified and compared with exact calculations. A magnetic field induces transitions between the ground and excited states. These transitions were analyzed in terms of crossings between single-particle states, singlet-triplet transitions, spin polarization, and Hund's rule. These impurity-free quantum dots allow "atomic physics" experiments to be performed in magnetic field regimes not accessible for atoms.  相似文献   
38.
39.
The aim of this study was to evaluate the effects of thyroxine administration on morphometric parameters, expression of vascular endothelial growth factor (VEGF) and vascularization in the uterus and placenta and reproductive parameters in gilts at 70 days of gestation. At 150 days of age, i.e., before first heat, 20 gilts were randomly divided into two experimental groups: treated (n = 10) and control (n = 10). The treated group received a daily dose of 400 μg of l ‐thyroxine (T4) in their diet until slaughter and the control group received only typical meals. Before artificial insemination, blood was collected to determine plasma total T4. The gilts were inseminated in the second oestrus and slaughtered at 70 days of gestation. The foetal thyroid follicular epithelium height, number, size and weight of foetuses; foetal myogenesis, corpora lutea number, embryonic mortality rate, uterine weight, placental weight and placental fluid volume were measured. Histomorphometric and immunohistochemical analysis of uterus and placenta were determined. The averages of all variables were compared by the Student’s t‐test. The gilts treated with thyroxine showed significant increase of plasma total T4. At 70 days of gestation, the heights of the trophoblastic epithelium, endometrial epithelium and endometrial gland epithelium were significantly higher in the group treated with T4. The expression of cytoplasmatic and nuclear VEGF in trophoblastic cells and the number of blood vessels per field in endometrial stroma were significantly higher in the gilts treated with T4. No other significant differences between groups were obtained with respect to other parameters (p > 0.05). We conclude that oral administration of T4 up to 70 days of pregnancy in gilts affects the morphometric parameters, the expression of placental VEGF and the uterine vascularization but does not affect reproductive parameters in gilts during early gestation.  相似文献   
40.
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