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91.
Complications associated with equine castration are the most common cause of malpractice claims against equine practitioners in North America. An understanding of the embryological development and surgical anatomy is essential to differentiate abnormal from normal structures and to minimise complications. Castration of the normal horse can be performed using sedation and regional anaesthesia while the horse is standing, or under general anaesthesia when it is recumbent. Castration of cryptorchid horses is best performed under general anaesthesia at a surgical facility. Techniques for castration include open, closed and half-closed techniques. Failure of left and right testicles to descend occurs with nearly equal frequency, however, the left testicle is found in the abdomen in 75% of cryptorchid horses compared to 42% of right testicles. Bilateral cryptorchid and monorchid horses are uncommon. Surgical approaches described for the castration of cryptorchid horses include an inguinal approach with or without retrieval of the scrotal ligament, a parainguinal approach, or less commonly a suprapubic paramedian or flank approach. Laparoscopic castration of cryptorchid horses has recently been described but the technique has limited application in practice at this time. A definitive diagnosis of monorchidism can only be made after surgical exploration of the abdomen, removal of the normal testis and hormonal testing. Hormonal assays reported to be useful include analysis of basal plasma or serum testosterone or oestrone sulphate concentrations, testosterone concentrations following hCG stimulation, and faecal oestrone sulphate concentrations. Reported complications of castration include postoperative swelling, excessive haemorrhage, eventration, funiculitis, peritonitis, hydrocele, penile damage and continued stallion-like behaviour.  相似文献   
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Upper mantle xenoliths found in ocean island basalts are an important window through which the oceanic mantle lithosphere may be viewed directly. Osmium isotopic data on peridotite xenoliths from the Kerguelen Islands, an archipelago that is located on the northern Kerguelen Plateau in the southern Indian Ocean, demonstrate that pieces of mantle of diverse provenance are present beneath the Islands. In particular, peridotites with unradiogenic osmium and ancient rhenium-depletion ages (to 1.36 x 10(9) years old) may be pieces of the Gondwanaland subcontinental lithosphere that were incorporated into the Indian Ocean lithosphere as a result of the rifting process.  相似文献   
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A method for the characterization and quantitation of phyto-estrogenic lignans from pomegranate (Punica granatum L.) fruits and fruit-derived products by HPLC-DAD-MS(n) was developed. For this purpose, edible and nonedible parts of pomegranate (aril, peel, mesocarp, seed, and twigs), commercial juices, juices produced on pilot-plant scale, and encapsulated dietary supplements were analyzed. In addition to the peel, mesocarp, and twigs, lignans were detected in two juices obtained from entire fruits, four commercial juices, and three encapsulated pomegranate extracts. Isolariciresinol was the predominant lignan with contents of 5.0, 10.5, and 45.8 mg/kg dry matter in processed pomegranate mesocarp, peel, and twigs, respectively. In contrast, due to their low amounts, quantitation of lignans in pomegranate products was impossible. Therefore, contrary to previous assumptions, lignans were found to be less relevant in pomegranate-derived products. However, the byproduct from pomegranate processing may be used for lignan extraction. The method presented allows one to differentiate between pomegranate-derived products obtained from fruits without peels or by dejuicing applying low pressures, which were devoid of lignans, and those obtained from entire fruits applying high pressures, thus containing lignans. Consequently, this study helps to optimize process technology aiming at the recovery of preparations with well-desired compositions, which may reduce the risk of a wide range of diseases, such as certain types of cancer.  相似文献   
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The water balance of a certain soil profile in a certain time interval is subjected to changes of soil water content within the respective profile, and fluxes at its upper and lower boundary. Weighing lysimeters are valuable instruments for water‐balance studies. Typically, mass changes—thus, changes of soil profile water content—are detected by a weighing system, while seepage water outflow is measured by a tipping bucket, and precipitation data originate from a rain gauge. Hence, evapotranspiration as unknown component can be determined by solving a simple water‐balance equation. However, using separately measured precipitation data may cause implausible (negative) evapotranspiration. In this study, change of soil profile water content, seepage water, precipitation, and evapotranspiration were determined directly from 10‐min lysimeter data from 2011. Precipitation measured with the lysimeter was in total 20% greater than rain‐gauge values. Even dew formation was measured and considered as water‐balance component; however, its total amount was rather low. Evapotranspiration calculated on daily and hourly base indicated a sound correlation with measured data, but measured values were considerably smaller. Both calculated and measured dew amount were of the same magnitude. Comparison of lysimeter evapotranspiration with daily calculations (neglecting dew) and hourly computation (considering dew) delivered similar results. Generally, the utilized lysimeter facility and the specific data management provided sound water‐balance components with high accuracy and temporal resolution, respectively.  相似文献   
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Ohne ZusammenfassungMit 8 Abbildungen  相似文献   
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