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161.
Abstract. Recent developments in in situγ ray spectrometry offer a new approach to measuring the activity of radionuclides such as 137Cs and 40K in soils, and thus estimating erosion or deposition rates and field moist bulk density (ρm). Such estimates would be rapid and involve minimal site disturbance, especially important where archaeological remains are present. This paper presents the results of a pilot investigation of an eroded field in Scotland in which a portable hyper pure germanium (HPGe) detector was used to measure γ ray spectra in situ. The gamma (γ) photon flux observed at the soil surface is a function of the 137Cs inventory, its depth distribution characteristics and ρm. A coefficient, QCs, derived from the forward scattering of 137Cs γ ray photons within the soil profile relative to the 137Cs full energy peak (662 keV), was used to correct the in situ calibration for changes in the 137Cs vertical distribution in the ploughed field, a function of tillage, soil accumulation and ρm. Based on only 8 measurements, the agreement between in situγ ray spectrometry and soil sample measurements of 137Cs inventories improved from a non significant r2=0.05 to a significant r2=0.62 (P<0.05). Erosion and deposition rates calculated from the corrected in situ137Cs measurements had a similarly good agreement with those calculated from soil cores. Mean soil bulk density was also calculated using a separate coefficient, QK, derived from the forward scattering γ photons from 40K within the soil relative to the 40K full energy peak (1460 keV). Again there was good agreement with soil core measurements (r2=0.64; P<0.05). The precision of the in situ137Cs measurement was limited by the precision with which QCs can be estimated, a function of the low 137Cs deposition levels associated with the weapons testing fallout and relatively low detector efficiency (35%). In contrast, the precision of the in situ ρm determination was only limited by the spatial variability associated with soil sampling. 相似文献
162.
In mid-September, 1 month before the insertion of intravaginal pessaries to induce sexual activity, blood samples were collected every 4 days from 16 ewe lambs aged 7 months, in order to determine the incidence of ovulations by measurement of plasma progesterone concentrations. It has been studied whether the response to a progestagen treatment of ewe lambs apparently close to puberty could be modified by the onset of the ovarian events preceding puberty. The effect of the presence or absence of ovulations prior to progestagen treatment on the potential reproductive performance (fertility, litter size and fecundity), embryo development [embryo quality and interferon-tau (IFNτ) secretion], luteal function (progesterone secretion in vitro ) and endometrial progesterone content was studied in seven ovulating (Ov+) and nine nonovulating ewe lambs (Ov−) on day 14 after mating. The best potential reproductive results were obtained with Ov+ animals, although these differences could not be initially attributed to either different progesterone secretion in vitro or concentration of endometrial progesterone. Irrespective of the experimental groups, secretion of progesterone by luteal tissue from ewe lambs with normal embryos was significantly greater (p<0.05) than that of animals with abnormal embryos or with no embryos. Normal embryos secreted a higher amount of IFN-τ than those embryos classified as abnormal (p<0.07). In conclusion, ewe lambs which exhibit luteal activity before puberty have the highest levels of reproductive performances after a progestagen treatment. Corpora lutea from ewe lambs with normal embryos had higher rates of progesterone secretion in vitro and their embryos had a higher IFN-τ production by the embryos, indicating greater capacity for subsequent development. 相似文献
163.
1966年在苏联弗拉基米尔州设立了“自然纪念林”固定标准地。该林分为Ⅰ_a地位级的单层混交天然林。组成为8松2云,林分年龄150年(松树),每公顷蓄积为927.1 m~3,其中用材占93.3%,木材剩余物占6.4%,薪材占0.3%。用材中98%可造锯材,2%造矿柱。经过15年,林分组成和地位级仍与期初相同。欧洲赤松平均树高增长1.3m;但云杉变化很小。欧洲赤松和云杉平均直径分别增长0.8和1.6 cm。林分内林木虽有枯死,但“自然纪念林”林分仍具有很高生产力,是俄罗斯珍贵的森林。 相似文献
164.
MICHAEL A. PRICHARD DVM RICHARD P. HACKETT DVM MS Diplomate ACVS HOLLIS N. ERB DVM PhD 《Veterinary surgery : VS》1992,21(2):145-149
The records of 61 horses undergoing tooth repulsion for treatment of alveolar periostitis were reviewed. Seventeen of 36 horses (47%) in which maxillary teeth were removed had serious postoperative complications, such as infection of a second tooth, bone sequestration, chronic sinusitis, draining tracts, retained dental packing, feed impaction of the alveolus or sinus, suture-line dehiscence, or skin-flap sloughs. Eight horses required at least one additional surgical procedure. Eight of 25 horses (32%) in which mandibular teeth were removed had serious postoperative complications, and four horses required an additional surgical procedure. Hospitalization lasted 2 to 61 days (median, 22 days) for maxillary teeth and 3 to 35 days (median, 8 days) for mandibular teeth. Long-term follow-up (at least 5 months) was possible in 47 horses. Twenty-four of 30 horses (80%) with maxillary tooth repulsion healed without further problems; six horses had persistent nasal discharge. Fourteen of 17 horses (82%) with mandibular tooth repulsion healed with no further problems or with only minor complications; three horses had a chronic draining tract. 相似文献
165.
Meat regulations also involve game inspection. This publication deals with the regulations concerning furred game intended for slaughter and furred game hunted for food. 相似文献
166.
The sera of 188 lambs from seven breed groups were analyzed for the concentrations of IgG1, IgG2, IgM and IgA by radial immunodiffusion using monospecific antibodies. From each lamb, 14 blood samples were drawn before and 5 samples after weaning. The following results were obtained: 1. Immunoglobulins could not be detected in sera drawn before the first intake of colostrum. 2. In normally suckling lambs, the peak concentrations of maternal immunoglobulins are attained at 0-18 hrs after birth. They can be assessed in a single blood sample drawn between 18 and 24 hrs. 3. The half-life times of maternal immunoglobulin in lamb sera are 11 days for IgG1, 7 days for IgG2, 6 days for IgM and 18 hours for IgA. 4. The absolute peak heights relate to the amounts of colostrum ingested before 12-18 hrs after birth. 5. The decline of maternal immunoglobulins in lamb sera over-laps with the onset of lamb immunoglobulin synthesis. Renewed rises of concentrations are observed for IgG2 after week 2, for IgM after week 3 and for IgG1 after week 7. The concentrations of IgA remain at the low levels characteristic for the serum of grown sheep. 6. The role of immunoglobulin synthesis in suckling lambs is only briefly and to a small extent reduced after weaning. 相似文献
167.
168.
Evaluation of an enzyme-linked immunosorbent assay for detection of antibodies to bovine virus diarrhoea virus in milk 总被引:3,自引:0,他引:3
R Niskanen S Alenius B Larsson N Juntti 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1989,36(2):113-118
The present study shows that milk is an appropriate source for detection of seroreactors to bovine virus diarrhoea virus (BVDV). There was close agreement between antibody titres in serum and in skim milk, as determined by an indirect enzyme-linked immunosorbent assay. The antibody titres were usually lower in skim milk than in serum, but all seropositive cows (n = 84) were also skim milk-positive and all but one seronegative cow (n = 55) proved negative in skim milk. During lactation, the level of antibodies to BVDV in milk showed an inverse relationship to the amount of milk produced. However, there was a sufficient level of antibodies in milk throughout lactation to permit an adequate determination of BVDV antibody status in dairy cows. There was a mutual good agreement between milk antibody titre in the four mammary quarters, irrespective of milk cell count. Milk can be used to detect seroreactors to BVDV. Milk is preferable to blood in large-scale epidemiological studies, since the sampling procedure is much simpler. 相似文献
169.
In our experience the camel (Camelus dromedarius) seems to be affected more commonly by dermoid cysts as compared to other cutaneous cysts. However, apart from one reference (Monteverde, 1935), the dermoid cyst has not been reported in the camel. This report documents dermoid cysts in identical locations in 11 camels with two camels having bilateral dermoid cysts at the similar site. 相似文献
170.
W M Kuzon Jr J D Rosenblatt B R Pynn P J Marchetti M J Plyley N H McKee 《Canadian journal of veterinary research》1989,53(2):125-132
The purpose of this study was to determine whether there were differences in skeletal muscle properties in the hindlimb muscles of different types of dogs. Muscle samples were obtained from the gracilis, sartorius cranial head, sartorius caudal head and tibialis anterior muscles of mixed-breed and hound-type dogs and Beagles. Fiber type, fiber size and capillary morphometry determinations of each muscle from each dog were made from sections stained for myofibrillar ATPase activity. Individual animals were bilaterally symmetric for all measured variables. Fiber type, fiber size and capillary geometry varied between dogs of a given type and muscles within a given dog. There were no differences between dog types for fiber type or fiber size; significant variation in log(muscle)/log(body) mass ratios between dog types was observed for all muscles. The results indicate that for a given muscle, significant variation can occur in skeletal muscle characteristics between different types of dogs and that these differences can be independent of differences in exercise history. 相似文献