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91.
The calcium carbonate in freshwater clam shells is simlilar in purity to that designated reagent grade. A simple reprecipitation of the shell extract results in a product having less Sr and Mg than reagent grade CaCO(3). Clams are harvested commercially, and discarded shells are a high-quality raw material for the production of CaCO(3).  相似文献   
92.
A paired-ion liquid chromatographic (LC) technique coupled with fluorometric detection to determine riboflavin in various food matrices is described. Chromatograms of many foods showed 2 peaks of interest due to presence of riboflavin and flavin mononucleotide (FMN). Relatively high levels of FMN were found in raw beef, corned beef, chicken liver, and canned mushrooms. When riboflavin and FMN contents were summed, LC values were comparable to those obtained by the AOAC standard procedures. The LC technique was sensitive, rapid, and simple, yielding a mean standard deviation of 3.1% which was comparable to the AOAC fluorometric method (3.0%) and better than the AOAC microbiological assay (9.6%). Mean spike recoveries were 91.8% for LC compared to 90.5% and 89.6% for the AOAC fluorometric and microbiological methods, respectively.  相似文献   
93.
Eight healthy mongrel dogs were treated with half-body irradiation (HBI) in a pilot study to evaluate the technique and radiotolerance of different organs. Cranial and caudal half-body fields were established using the 13th thoracic vertebra as the dividing point. Under general anesthesia, either 7 or 8 Gray (Gy) were delivered to one half of the body using opposing radiation portals. The other half of the body was similarly treated 28 days later. The dogs were monitored for 12 months. Significant radiation effects included transient bone marrow suppression and radiation sickness. There were no serious or life-threatening problems, but the 8 Gy group consistently showed more severe clinical signs and histologic changes than the 7 Gy group. Total body irradiation in two fractions of 7 or 8 Gy given 1 month apart appears to be a safe treatment that can be developed for therapy in veterinary oncology.  相似文献   
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In many instances, the cause for malassimilation can be determined with ease, but finding the cause sometimes can be elusive and require the use of sophisticated laboratory techniques not available to the general veterinary practitioner. In either case, the clinician, whether generalist or specialist, must make an informed decision based on the results of many different testing modalities, and not only on the results of the laboratory tests described here. A flow chart is provided to assist the diagnostician in selecting and applying the more clinically oriented laboratory tests useful in dealing with a patient with chronic diarrhea and weight loss.  相似文献   
97.
Truck-drivers and previous owners of sheep from 133 farms (lines of sheep) were asked for information on possible risk factors for inappetance during lot-feeding and for shipboard mortality during 5 voyages to the Middle East. There was no consistent association between a number of factors prior to trucking or during trucking to the feedlot and inappetance during lot-feeding or mortality aboard ship. The factors included: whether sheep were bred or purchased by the owner, whether sheep were mixed with sheep from another farm in the previous 2 or 6 months, previous experience of trucking, frequency of yarding, experience of supplementary feeding, age, rainfall zone of the farm of origin, distance trucked, time on the truck and time off feed on arrival at the feedlot. Inappetance during lot-feeding was significantly associated with total deaths aboard ship for individuals and for lines of sheep. Failure to eat late in the feedlot period was also a risk factor for individuals that died with inanition (relative risk = 6.9) or salmonellosis (relative risk = 5.9). In 2 voyages, there was no significant difference in shipboard death rate between groups that were previously lot-fed in sheds or in paddocks. This was despite significantly more non-feeders in the sheds than in the paddocks prior to one voyage. This finding suggested that some nonfeeders commenced eating pellets aboard the ship. Although inappetance in the feedlot was a risk factor for shipboard deaths, there was no difference in shipboard weight change between feedlot non-feeders and feeders in 2 voyages. It was concluded that most non-feeders began eating pelleted feed aboard ship.  相似文献   
98.
When erythrocytes from sheep experimentally infected with Eperythrozoon ovis were used in the titration of reagents for a standardised complement fixation test, increased amounts of both haemolysin and complement were required for erythrocyte lysis compared with preinfection titrations. The haemolysin requirement increased by up to 125% at 55 days post-infection and complement requirement increased by up to 40% at 40 days post-infection. These changes appeared to correlate with the development of a macrocytic anaemia in affected sheep rather than E. ovis parasitaemia. The results emphasise the need to carefully monitor the haematological parameters of sheep used as sources of erythrocytes for the complement fixation test.  相似文献   
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Interstitial lung diseases are a heterogeneous group of disorders with a variety of causes. In veterinary medicine, such lung diseases with a prominent fibrotic component of unknown etiology are often called idiopathic pulmonary fibrosis (IPF). In human medicine, this term is reserved for a distinct disease entity with specific histologic findings labeled as usual interstitial pneumonia (UIP). We identified 23 cats displaying histologic criteria of UIP The purpose of this retrospective study is to describe the presentation and response to therapy of these cats to better define this disease entity. All but 2 cats were middle aged to older (median 8.7 years), with no apparent sex or breed predisposition. Complaints included respiratory distress (n = 18) and cough (13). Duration of signs was less than 6 months in 17 cats. Physical-examination abnormalities included tachypnea, inspiratory or mixed inspiratory and expiratory effort, and adventitial lung sounds. No consistent hematologic or biochemical abnormalities, parasites, or positive serologic results for feline retroviruses, heartworms, or toxoplasmosis were present. Radiographic changes included dense patchy or diffuse interstitial, bronchiolar, and alveolar infiltrates. Analysis of bronchial lavage fluid revealed mild neutrophilic inflammation (n = 6) with no consistent pathogen growth. Clinical condition of 5 cats worsened after lavage. Coincident pulmonary neoplasia was identified in 6 cats. Response to therapy (corticosteroids, antibiotics, bronchodilators, and diuretics) was poor, and most cats died within days to months. Cats with histologic changes compatible with UIP had signs that mimicked many of the clinical findings of human IPF, and treatment response was similarly unrewarding.  相似文献   
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