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81.
Anaplasma (A.) phagocytophilum is a tick-transmitted obligate intracellular bacterium and has been identified in a wide range of mammalian species, causing febrile disease in some. Few reports show that it can also cause granulocytic anaplasmosis in cats. As data on the occurrence of A. phagocytophilum in cats from Germany is limited, a total of 326 serum and 306 EDTA-blood samples from cats from Germany were screened by direct (Giemsa-stained blood/buffy coat smears, real-time PCR) and indirect (IFAT) methods. Of 274 Giemsa-stained blood smears which could be evaluated none was positive for morulae, but one blood sample (< or =0.1%; 1/306) was positive for A. < or = phagocytophilum-DNA in PCR. Antibodies (cutoff > or = 1:64) were detected in 53 out of 326 samples (16.2%). Altogether, the results show a high seroprevalence rate of anti-A. phagocytophilum antibodies in cats in Germany while the low detection rate of this bacterial agent by direct methods is similar to those of other studies on A. phagocytophilum infections in cats.  相似文献   
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83.
In this study, we investigated how co-occurrence patters of ammonia and nitrite oxidizers, which drive autotrophic nitrification, are influenced by tree species composition as well as soil pH in different forest soils. We expected that a decline of ammonia oxidizers in coniferous forests, as a result of excreted nitrification inhibitors and at acidic sites with low availability of ammonia, would reduce the abundance of nitrite-oxidizing bacteria (NOB). To detect shifts in co-occurrence patterns, the abundance of key players was measured at 50 forest plots with coniferous respectively deciduous vegetation and different soil pH levels in the region Schwäbische Alb (Germany). We found ammonia-oxidizing archaea (AOA) and Nitrospira-like NOB (NS) to be dominating in numbers over their counterparts across all forest types. AOA co-occurred mostly with NS, while bacterial ammonia oxidizers (AOB) were correlated with Nitrobacter-like NOB (NB). Co-occurrence patterns changed from tight significant relationships of all ammonia and nitrite oxidizers in deciduous forests to a significant relationship of AOB and NB in coniferous forests, where AOA abundance was reduced. Surprisingly, no co-occurrence structures between ammonia and nitrite oxidizers could be determined at acidic sites, although abundances were correlated to the respective nitrogen pools. This raises the question whether interactions with heterotrophic nitrifiers may occur, which needs to be addressed in future studies.  相似文献   
84.
Since computed tomography (CT) was introduced to veterinary medicine in the beginnings of the 80s, the CT of the skull has mainly been used for the diagnosis of brain tumors. The present study includes 18 dogs and five cats, all patients of the Clinic of Small Animals of the School of Veterinary Medicine Hannover. After a CT of their skull was made, a primary intracranial neoplasm was confirmed by a pathomorphological and -histogical examination post mortem. Four of the five cats had a meningioma, one cat an astrocytoma. With five cases the meningioma also predominated in the dogs, followed by primary lymphoma with four cases. An astrocytoma, an oligodendroglioma and a choroid plexus papilloma were diagnosed respectively in two dogs. A pituitary gland tumor, a germ cell tumor and a medulloblastoma represented individual cases. Based on the pathomorphologically and -histologically confirmed diagnosis, characteristics of these primary brain neoplasms can be found in their CT image. However, changes are not pathognomonic for a certain type of tumor; a definitive diagnosis cannot be made from the CT image.  相似文献   
85.
In order to establish reference values for corneal sensitivity in ophthalmologically healthy persians (n = 40) and domestic short hair cats (n = 60) a prospective study was conducted. Furthermore corneal sensitivity in 48 cats with a corneal sequestrum was measured. Corneal sensitivity was recorded with the help of the aesthesiometer according to Cochet and Bonnet in five different corneal locations (central, nasal, dorsal, temporal, and ventral). The sensitivity for the central corneal region was recorded as amounting to 3.58 +/- 0.56 cm in ophthalmologically healthy domestic short hair cats and to 2.97 +/- 0.58 cm in healthy persian cats. The sensitivity of the central corneal area of a cat with a corneal sequester only amounts to 2.03 +/- 0.53 cm. Between the diseased and the healthy eyes no statistical difference could be demonstrated for any of the measured corneal locations. The sensitivity of the peripheral corneal locations is significantly lower than that of the central corneal region in all three groups examined.  相似文献   
86.
In order to investigate the way in which fibre properties affect the mechano-sorptive creep phenomenon in paper, single wood fibres were exposed to tensile stresses at a constant humidity of 80% relative humidity (RH) and in a cyclic humidity environment varying between 80 and 30% RH. Contrary to earlier claims, it was demonstrated that single wood fibres exposed to a cyclic RH show a considerably higher creep than that corresponding to the highest RH experienced in the cycle, i.e., a mechano-sorptive behaviour. The creep strain rate at cyclic humidity was shown to be a function of the creep rate at constant climate, and to be an apparent linear function of the applied stress.  相似文献   
87.
Regeneration patterns of Pinus sylvestris L. juveniles in central Siberian glades were studied in relation to cold-induced photoinhibition. Spatial distribution of seedlings in different height classes revealed higher seedling densities beneath the canopy than beyond the canopy, and significantly higher densities of seedlings < 50 cm tall on the north side of the trees. These patterns coincided with differences in light conditions. Compared with plants on the north side of canopy trees (north-exposed), photosynthetic photon flux (PPF) received by plants on the south side of canopy trees (south-exposed) was always higher, making south-exposed plants more susceptible to photoinhibition, especially on cool mornings. Chlorophyll fluorescence data revealed lower photochemical efficiency and increased non-photochemical quenching of small (20-50 cm in height), south-exposed seedlings from spring to early autumn, indicating increased excitation pressure on photosynthesis. Maximum rate of oxygen evolution was less in south-exposed plants than in north-exposed plants. Increased pools of xanthophyll cycle pigments and formation of the photoprotective zeaxanthin provided further evidence for the higher susceptibility to photoinhibition of south-exposed seedlings. A linear mixed model analysis explained many of the physiological differences observed in seedlings according to height class and aspect with early morning temperature and PPF as predictors. The link between photoinhibition and differential distribution of seedlings by height class suggests that photoinhibition, together with other environmental stresses, decreases the survival of small, south-exposed P. sylvestris seedlings, thereby significantly affecting the regeneration pattern of central Siberian pine glades.  相似文献   
88.
In a cohort study involving 62 cows from an experimental farm, the kinetics of the glutaraldehyde test (GAT) according to Sandholm (1974) was examined by testing samples of EDTA blood, lithium heparinate blood, serum, and plasma taken at various intervals. Total protein was measured in serum, and fibrinogen was determined in plasma. Gamma globulin was measured by electrophoresis. All glutaraldehyde tests were performed in duplicates, and the relation of the two results was used as measurement of precision. Optimal cut-off of the GAT time was determined as the zenith of the sum of sensitivity and specificity of various intervals for detecting combinations of gamma globulin and fibrinogen levels above 32 g/l. Precision was the best in EDTA blood. The relation between coagulation time and gamma globulin plus fibrinogen is best described by an exponential curve. The maximum value for the sum of sensitivity and specificity was found at 7 and 8 min. Seven days was the shortest interval observed between a negative test result (>15 min) and a strongly positive test result (<3 min). Twenty-one days was the shortest interval observed between a strongly positive test result and a negative test result. EDTA blood should be used for the GAT. A cut-off of 8 min yields the highest efficiency. Test results must be viewed in light of clinical findings.  相似文献   
89.
Objective— To compare analgesic efficacy of preoperative versus postoperative administration of carprofen and to determine, if preincisional mepivacaine epidural anesthesia improves postoperative analgesia in dogs treated with carprofen. Study Design— Blind, randomized clinical study. Animals— Dogs with femoral (n=18) or pelvic (27) fractures. Methods— Dogs were grouped by restricted randomization into 4 groups: group 1=carprofen (4 mg/kg subcutaneously) immediately before induction of anesthesia, no epidural anesthesia; group 2=carprofen immediately after extubation, no epidural anesthesia; group 3=carprofen immediately before induction, mepivacaine epidural block 15 minutes before surgical incision; and group 4=mepivacaine epidural block 15 minutes before surgical incision, carprofen after extubation. All dogs were administered carprofen (4 mg/kg, subcutaneously, once daily) for 4 days after surgery. Physiologic variables, nociceptive threshold, lameness score, pain, and sedation (numerical rating scale [NRS], visual analog scale [VAS]), plasma glucose and cortisol concentration, renal function, and hemostatic variables were measured preoperatively and at various times after surgery. Dogs with VAS pain scores >30 were administered rescue analgesia. Results— Group 3 and 4 dogs had significantly lower pain scores and amount of rescue analgesia compared with groups 1 and 2. VAS and NRS pain scores were not significantly different among groups 1 and 2 or among groups 3 and 4. There was no treatment effect on renal function and hemostatic variables. Conclusions— Preoperative carprofen combined with mepivacaine epidural anesthesia had superior postoperative analgesia compared with preoperative carprofen alone. When preoperative epidural anesthesia was performed, preoperative administration of carprofen did not improve postoperative analgesia compared with postoperative administration of carprofen. Clinical Relevance— Preoperative administration of systemic opioid agonists in combination with regional anesthesia and postoperative administration of carprofen provides safe and effective pain relieve in canine fracture repair.  相似文献   
90.
OBJECTIVE: To evaluate the influence of a tibial plateau leveling jig on osteotomy orientation, fragment reduction, and postoperative tibial plateau angle (TPA) during tibial plateau leveling osteotomy (TPLO). STUDY DESIGN: In vitro experimental study. ANIMALS: Large-breed canine cadavers (n=20). METHODS: TPLO was performed on 40 hindlimbs using 4 methods. Group 1: Jig; dogs in dorsal recumbency with the osteotomy parallel to the distal jig pin. Groups 2-4: No jig; dogs in lateral recumbency with the osteotomy in a vertical orientation (group 2: tibia parallel to the table top; group 3: controlled superimposition of the femoral condyles; group 4: internal rotation of the tibia). Postoperative TPA, fragment reduction, and osteotomy orientation relative to the tibial plateau were compared. Positive or negative values denoted deviation from parallel relative to the tibial plateau. RESULTS: Postoperative TPA, fragment reduction, and proximodistal osteotomy orientation were not significantly different between groups. Craniocaudal osteotomy orientation was significantly different (P<.005) from the tibial plateau. Median deviations were -4.0 degrees (group 1), 11.8 degrees (group 2), 11.2 degrees (group 3), and 0.2 degrees (group 4). Group 1 was not significantly different from group 4. CONCLUSIONS: A jig is not essential for osteotomy orientation, tibial plateau rotation, or fragment reduction. Comparable results were achieved performing a vertical osteotomy with the tibia slightly internally rotated (10 degrees -15 degrees) and parallel to the table surface. CLINICAL RELEVANCE: TPLO without use of a jig reduces surgical trauma, is less time consuming, and reduces cost.  相似文献   
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