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61.
We aimed to study the normal puerperium in the bitch. Ovariohysterectomy was performed in nine bitches, each at a different day after normal whelping; their genital tract was subject to gross anatomical examination, as well as to histological examination and electron microscopy scanning. Corpora albicans were evenly distributed in the left and right ovaries and placental sites were evenly distributed among left and right uterine horns. Placental sites were initially of dark green to grey colour, later becoming dark brown; their length and height progressively decreased. Height of the myometrium and diameter of the uterine glands progressively decreased. Trophoblast-like cells were consistently observed at the placental sites and on the surface of the interplacental areas, at all time points where hysterectomy had been performed. It is suggested that involution of the canine genital tract can last up to 3 months and is slow. Continuous (up to D84 post-partum) presence of prominent placental sites should be considered a normal feature of canine uterine post-partum involution.  相似文献   
62.
The quantitative role of sheep in the transmission of foot-and-mouth disease virus (FMDV) is not well known. To estimate the role of sheep in the transmission of FMDV, a direct contact transmission experiment with 10 groups of animals each consisting of 2 infected lambs and 1 contact calf was performed. Secretions and excretions (oral swabs, blood, urine, faeces and probang samples) from all animals were tested for the presence of FMDV by virus isolation (VI) and/or RT-PCR. Serum was tested for the presence of antibodies against FMDV. To estimate FMDV transmission, the VI, RT-PCR and serology results were used. The partial reproduction ratio R0p i.e. the average number of new infections caused by one infected sheep introduced into a population of susceptible cattle, was estimated using either data of the whole infection chain of the experimental epidemics (the transient state method) or the final sizes of the experimental epidemics (the final size method). Using the transient state method, R0p was estimated as 1.0 (95% CI 0.2 - 6.0) using virus isolation results and 1.4 (95% CI 0.3 - 8.0) using RT-PCR results. Using the final size method, R0p was estimated as 0.9 (95% CI 0.2 - 3.0). Finally, R0p was compared to the R0’s obtained in previous transmission studies with sheep or cattle only. This comparison showed that the infectivity of sheep is lower than that of cattle and that sheep and cattle are similarly susceptible to FMD. These results indicate that in a mixed population of sheep and cattle, sheep play a more limited role in the transmission of FMDV than cattle.  相似文献   
63.
AIM: To compare the rectal and I/V administration of tramadol in dogs, to assess both its pharmacokinetic properties and absolute bioavailability.

METHODS: After rectal administration via suppositories and I/V injection of tramadol (4 mg/kg), the concentration of tramadol and its main metabolites, O-desmethyl-tramadol (M1), N-desmethyl-tramadol (M2) and N,O-didesmethyl-tramadol (M5), were determined in plasma, using high-performance liquid chromatography (HPLC). A balanced cross-over study was used, involving six male Beagle dogs.

RESULTS: Plasma concentrations after rectal and I/V administration were fitted on the basis of mono- and bi-compartmental models, respectively. Following rectal administration tramadol was detected from 5 minutes up to 10 hours, in lesser amounts than M5 and M2, while M1 was detected in negligible amounts. Following I/V administration tramadol was detected up to 10 hours, M2 and M5 were detected at similar concentrations, and M1 was present at low concentrations. The area under the curve (AUC) of the three metabolites did not differ significantly after either route of administration of tramadol. The absolute bioavailability of tramadol via rectal administration was 10 (SD 4)%.

CONCLUSIONS: After rectal administration of tramadol suppositories, absorption of the active ingredient was rapid, but its metabolism quickly transformed the parent drug to high levels of M2 and M5.

CLINICAL RELEVANCE: In the dog, rectal pharmaceutical formulation of tramadol would have a different pharmacokinetic behaviour than in humans.  相似文献   
64.
The current study examined the protective effects of l ‐glutamine and cytochalasin B during vitrification of immature bovine oocytes. Oocyte vitrification solution (PBS supplemented with 10% FCS, 25% EG, 25% DMSO and 0.5 m trehalose) was the vitrification control. Treatments were the addition of 7 μg/ml cytochalasin B, 80 mm glutamine or both cytochalasin and glutaminine for 30 s. After warming, oocytes were matured in vitro for 24 h, fixed and stained with Hoechst (33342) for nuclear maturation evaluation. l ‐glutamine improved the vitrified/warmed immature bovine oocytes viability (32.8%), increasing the nuclear maturation rates compared to other treatments and the no treatment vitrified control (17.4%). There was, however, no effect of cytochalasin B on in vitro maturation (14.4%).  相似文献   
65.
The Sierra Madre fault, along the southern flank of the San Gabriel Mountains in the Los Angeles region, has failed in magnitude 7.2 to 7.6 events at least twice in the past 15,000 years. Restoration of slip on the fault indicated a minimum of about 4.0 meters of slip from the most recent earthquake and suggests a total cumulative slip of about 10.5 meters for the past two prehistoric earthquakes. Large surface displacements and strong ground motions resulting from greater than magnitude 7 earthquakes within the Los Angeles region are not yet considered in most seismic hazard and risk assessments.  相似文献   
66.
Central Greenland ice cores provide evidence of abrupt changes in climate over the past 100,000 years. Many of these changes have also been identified in sedimentary and geochemical signatures in deep-sea sediment cores from the North Atlantic, confirming the link between millennial-scale climate variability and ocean thermohaline circulation. It is shown here that two of the most prominent North Atlantic events-the rapid warming that marks the end of the last glacial period and the Bolling/Allerod-Younger Dryas oscillation-are also recorded in an ice core from Taylor Dome, in the western Ross Sea sector of Antarctica. This result contrasts with evidence from ice cores in other regions of Antarctica, which show an asynchronous response between the Northern and Southern Hemispheres.  相似文献   
67.
Community respiration (R) rates are scaled as the two-thirds power of the gross primary production (P) rates of aquatic ecosystems, indicating that the role of aquatic biota as carbon dioxide sources or sinks depends on its productivity. Unproductive aquatic ecosystems support a disproportionately higher respiration rate than that of productive aquatic ecosystems, tend to be heterotrophic (R > P), and act as carbon dioxide sources. The average P required for aquatic ecosystems to become autotrophic (P > R) is over an order of magnitude greater for marshes than for the open sea. Although four-fifths of the upper ocean is expected to be net heterotrophic, this carbon demand can be balanced by the excess production over the remaining one-fifth of the ocean.  相似文献   
68.
69.
A questionnaire regarding attitudes to undergraduate education in genetics and the subsequent use of that education was sent to 1000 veterinarians registered in New South Wales. Three hundred replies to the questionnaire were received and analysed. No significant difference in the perceived adequacy of courses at the four universities involved in teaching veterinary science was observed. Opinions on adequacy of education in genetics were not affected by age, sex or years since graduation. The major reason cited for lack of adequacy was that undergraduate genetics courses were not practical. Only 17 respondents stated that they were never approached for information on genetics or animal breeding, while 76 were approached more than 20 times annually for information. Eighty-three respondents claimed to deal with more than 20 cases annually that required some knowledge of genetics. The results of the questionnaire highlight the importance of genetics instruction in undergraduate veterinary education. The questionnaire responses also provide insight into how working veterinarians consider that courses in genetics could be improved.  相似文献   
70.
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