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11.
AIMS: To retrospectively evaluate the medical and surgical records of horses with acute small intestinal obstructions associated with Parascaris equorum infection; to describe the gastrointestinal lesions; and to determine the outcome of cases with such lesions.

METHODS: Records of 25 horses with acute small intestinal obstruction associated with P. equorum between 1985 and 2004 were reviewed to determine signalment, history, physical examination, surgical or post-mortem findings, and outcome.

RESULTS: All horses except one were less than 12 months old. Standardbreds were over-represented in the population studied. Sixteen horses (72%) had been administered anthelmintics, including pyrantel (n=8), ivermectin (n=7), and trichlorphon (n=1), within 24 h prior to the onset of colic. Of the 25 cases reviewed, 16 had simple obstructive ascarid impactions (SOAIs), and nine had complicated obstructive ascarid impaction (COAI) including volvulus (n=6) or intussusception (n=3), both concurrent with ascarid impaction of the small intestine. Short-term survival (discharge from hospital) occurred in 79% of horses treated for SOAI, and was 64% for all horses. Long-term survival (>1 year) occurred in 33% of horses with SOAI, and the overall long-term survival was 27% for all horses. Formation of adhesions was the most frequent finding associated with death for horses that did not survive long-term.

CONCLUSIONS AND CLINICAL RELEVANCE: The incidence of anthelmintic treatment within 24 h of the onset of colic in this study population (72%) was higher than that previously reported. Resistance of P. equorum to ivermectin recently reported in Ontario may be associated with increased ascarid burdens, predisposing horses to ascarid impaction. The long-term survival of these horses was better than that reported previously.  相似文献   
12.
The consumption of colostrum at a low level can compromise the survival and growth of piglets. Therefore, this study aimed to evaluate the effect of farrowing induction on colostrum yield, IgG concentration and the survival and performance of piglets until the weaning. Sows of parity 3 to 7 were assigned into two groups: Control (n = 48), sows with spontaneous farrowing; and induction (n = 48), sows induced to farrow on day 114 of gestation with a PGF2 analogue. Colostrum and blood samples were collected from the sows, at farrowing and 24 hr later. Blood samples from the piglets were collected at 24 hr after birth. The performance of the piglets was evaluated in a subsample of 28 litters from each group. All piglets were weighed at 7, 14 and 20 days of age. The farrowing length, the number of piglets born alive, stillborn piglets, weight at birth, litter weight at birth and colostrum yield were not significantly affected (p > .05) by farrowing induction. There was no difference between the groups (p > .05) in the percentage of sows with obstetric interventions. Serum IgG concentration, in both sows and piglets, and colostrum IgG concentration were similar between the groups (p > .05). Furthermore, survival rate, piglet weight and litter weight at 7, 14 and 20 days of age were also similar between the groups (p > .05). Therefore, it can be concluded that the farrowing induction performed on day 114 of gestation does not affect the colostrum yield, the IgG concentration in colostrum and serum of piglets, and the litter performance until the weaning.  相似文献   
13.
A tunable kondo effect in quantum dots   总被引:1,自引:0,他引:1  
A tunable Kondo effect has been realized in small quantum dots. A dot can be switched from a Kondo system to a non-Kondo system as the number of electrons on the dot is changed from odd to even. The Kondo temperature can be tuned by means of a gate voltage as a single-particle energy state nears the Fermi energy. Measurements of the temperature and magnetic field dependence of a Coulomb-blockaded dot show good agreement with predictions of both equilibrium and nonequilibrium Kondo effects.  相似文献   
14.
Deng L  Xiang LP  Liang YR 《茶叶》2013,(4):486-490
Aftertaste is a taste perceiption after a food or beverage is either swallowed or spat out.The primary taste processing area located in the insula was considered to be involved in aftertaste perception.The changes in chemical compositions lead to the changes in aftertaste of tea.Tea fermentation,in which tea catechins are transformed into thearubigins,lead to a strong,distinctive flavor but a plain aftertaste.Theanine has a sweet taste,with little or no aftertaste.The bitter aftertaste of transglucosylated steviosides was reduced when they were converted through transglucosylation of stevioside by α-amylase.Characteristics of aftertaste include quality,intensity,and duration.Foods that have lingering aftertastes typically have long sensation durations.A surface plasmon resonance (SPR) system immobilized β-cyclodextrin indicated larger responses for the gallate-type catechins in comparison to the non-gallate-type catechins.The β-cyclodextrin/SPR system can sense the bitter-astringent taste intensity of the green tea.The SPR system detected the stability of the complex between the gallate-type catechins and β-cyclodextrin,which can be interpreted as the aftertaste produced in humans by the gallate-type catechins.  相似文献   
15.
An epizootic of severe Cryptosporidium sp.-associated enteritis occurred in a group of 15 wild-caught juvenile rough green snakes (Opheodrys aestivus) at the Baltimore Zoo quarantine facility. All of the animals died with no premonitory signs. Histopathologic examination of the small and proximal large intestine of eight of the green snakes showed moderate to severe Cryptosporidium sp. infection and enteritis characterized by dense heterophilic and lymphocytic inflammatory infiltrates throughout the lamina propria with epithelial necrosis. Cryptosporidium sp. was also found in feces of an adult common garter snake (Thamnophis sirtalis) that was wild caught on zoo grounds and held in quarantine during the epizootic. After euthanasia, histologic examination of the garter snake showed a severe small intestinal Cryptosporidium sp. infection with only mild enteritis consisting of sparse heterophilic and lymphocytic infiltrates. There was no gross or histologic evidence of Cryptosporidium sp. gastritis in the nine snakes evaluated, and this is the first report of Cryptosporidium sp.-associated enteritis in snakes without gastric lesions.  相似文献   
16.
Human serological assays designed to detect brucellosis will miss infections caused by Brucella canis, and low levels of periodic bacteremia limit diagnosis by blood culture. Recent B. canis outbreaks in dogs and concomitant illnesses in caretakers suggest that unapparent human infections may be occurring. With more than a quarter of a million persons in occupations involving dogs, and nearly 80 million dog owners in the United States, this pathogen is an under‐recognized human health threat. To investigate occupational exposure to B. canis, we adapted a commercial canine serological assay and present the first controlled seroepidemiological study of human B. canis infections in recent years. 306 adults with occupational exposure to dogs and 101 non‐matched, non‐canine‐exposed subjects were enrolled. Antibodies were detected using the canine D‐Tec® CB rapid slide agglutination test (RSAT) kit with a secondary 2‐mercaptoethanol (ME)‐RSAT. Results were validated on a blinded subset of sera with an additional RSAT and indirect enzyme‐linked immunoassay at the National Administration of Laboratories and Health Institutes (ANLIS) in Argentina. Seroprevalence ranged from 10.8% (RSAT) to 3.6% (ME‐RSAT) among canine‐exposed subjects. Kennel employees were more likely to test RSAT seropositive compared with other canine exposures (OR = 2.7; 95% CI, 1.3–5.8); however, low seroprevalence limited meaningful occupational risk factor analyses. Two seropositive participants reported experiencing symptoms consistent with brucellosis and having exposure to B. canis‐infected dogs; however, temporality of symptom onset with reported exposure could not be determined. D‐Tec® CB results had substantial agreement with ANLIS assays (Cohen's kappa = 0.60–0.68). These data add to a growing body of literature suggesting that people occupationally exposed to dogs may be at risk of unapparent B. canis infection. It seems prudent to consider B. canis as an occupational public health concern and encourage the development of serological assays to detect human B. canis infections.  相似文献   
17.
A new spectrophotometric assay has been used to determine the gross concentration of cardiac glycoside in individual monarch butterflies. Adults sampled during the fall migration in four areas of eastern North America exhibited a wide variation in cardiac glycoside concentration. The correlation between spectrophotometrically measured concentrations and emetic dose determinations supports the existence of a broad palatability spectrum in wild monarch butterflies. The cardiac gylcoside concentration is greater in females than in males and is independent of the dry weight of the butterflies; contrary to prediction, both the concentration mean and variance decrease southward. The defensive advantage of incorporating cardiac glycosides may be balanced by detrimental effects on individual viability.  相似文献   
18.
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   
19.
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   
20.
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