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111.
Distribution of thiobacillus ferrooxidans and leptospirillum ferrooxidans: implications for generation of acid mine drainage 总被引:1,自引:0,他引:1
MO Schrenk KJ Edwards RM Goodman RJ Hamers JF Banfield 《Science (New York, N.Y.)》1998,279(5356):1519-1522
Although Thiobacillus ferrooxidans and Leptospirillum ferrooxidans are widely considered to be the microorganisms that control the rate of generation of acid mine drainage, little is known about their natural distribution and abundance. Fluorescence in situ hybridization studies showed that at Iron Mountain, California, T. ferrooxidans occurs in peripheral slime-based communities (at pH over 1.3 and temperature under 30 degreesC) but not in important subsurface acid-forming environments (pH 0.3 to 0.7, temperature 30 degrees to 50 degreesC). Leptospirillum ferrooxidans is abundant in slimes and as a planktonic organism in environments with lower pH. Thiobacillus ferrooxidans affects the precipitation of ferric iron solids but plays a limited role in acid generation, and neither species controls direct catalysis at low pH at this site. 相似文献
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Abstract CASE HISTORIES: Three dogs, aged between 11 and 20 weeks, were presented with unilateral forelimb lameness, with an associated bony prominence on the lateral elbow. CLINICAL FINDINGS AND DIAGNOSIS: Radiographs revealed a caudolateral luxation of the radial head in all cases, consistent with a diagnosis of suspected congenital luxation of the radial head. Surgical reduction and stabilisation involved open reduction of the radial head, and in two cases the use of a trans articular pin. CLINICAL RELEVANCE: Congenital luxation of the radial head is an uncommon condition that has conflicting reports in the literature regarding its cause, heritability, breed predisposition, treatment and prognosis. The three cases here occurred in young dogs of English Bull Terrier, Jack Russell Terrier, and Staffordshire Bull Terrier breeds. Surgical reduction and stabilisation provided successful outcomes, in all cases. Only six cases of congenital luxation of the radial head managed surgically have previously been reported in the literature. 相似文献
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AIMS: To quantify the range of attitudes and perceptions of cattle practitioners to painful procedures and conditions in cattle, to identify some of the demographic factors affecting those attitudes and perceptions, and to compare results from veterinarians based in New Zealand with those from the United Kingdom (UK) and Europe. METHODS: A questionnaire, based on one used for similar surveys in Europe, was sent to all 455 members of the Society of Dairy Cattle Veterinarians (DCV) of the New Zealand Veterinary Association. This questionnaire included a section on demographic data, e.g. gender, year of graduation, and preveterinary school background, and a section which asked the respondents to rate on a scale of 1 to 10 how painful they thought 24 procedures and conditions would be without any analgesia. RESULTS: A total of 166 questionnaires were returned, a response rate of 37%. From the range of procedures and conditions outlined in the questionnaire, those perceived as most painful were claw amputation, then Caesarean section, followed by surgery for left-displaced abomasum (LDA). The two least painful were mastitis with milk clots only, and the effect on a calf of dystocia. There were significant differences between the pain scores assigned by men and women and by respondents who had graduated in different decades. Female respondents and more recent graduates tended to give a higher pain score for most conditions. These effects remained, even after the potential interaction between age and gender had been assessed. The effect on pain score of either background or time spent treating cattle was much less marked than the effect of age and gender. Overall, the results were very similar to results from similar surveys undertaken in the UK and Europe. CONCLUSIONS: The responses to this survey indicate that, as in the UK and Europe, dairy cattle practitioners in New Zealand have a wide range of attitudes to pain in cattle. The estimates of the severity of pain were subjective, but such a survey allows the majority opinion of a considerable number of informed assessors to be quantified. CLINCAL RELEVANCE: The wide range of results suggests that more needs to be done to disseminate up-to-date knowl- edge of pain in cattle to veterinarians to ensure they provide appropriate levels of analgesia. In particular, the baseline data from this study can be used by practitioners to identify whether they are underestimating pain in cattle and, if they are, to assess whether they are using analgesia appropriately. Additionally, this dataset provides an informed and independent assessment of the pain associated with husbandry procedures, and could be used to better guide legislation concerning pain control of such procedures. 相似文献
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The synchronization of follicular waves with medroxyprogesterone acetate (MAP) and oestradiol‐17β (E2‐17β) prior to ovarian superstimilation in anoestrous ewes reduces the variability in superovulatory responses by an unknown mechanism. Follicle stimulating hormone (FSH) is a primary promoter of antral follicular development, but the relevance of circulating FSH concentrations to the superovulation performance in ewes has not been examined. Eighteen anoestrous Rideau Arcott ewes (May–June) were superovulated with Folltropin®‐V (porcine FSH), with (n = 8; treated ewes) or without (n = 10; control ewes) a single i.m. dose of 350 μg of E2‐17β, given on the sixth day of a 14‐day treatment with MAP‐releasing intravaginal sponges (60 mg). The superovulatory treatment, begun 6 days after E2‐17β injection, consisted of six i.m. applications of Folltropin®‐V given twice daily (at 08:00 and 16:00 h), followed by an i.m. injection of GnRH (50 μg). Blood samples collected every 8 h throughout the 3‐day treatment, were analysed by radioimmunoassays for concentrations of ovine and porcine FSH, using species‐specific standards and primary antibodies. Serum concentrations of oFSH were greater (p < 0.05) in the controls compared to treated ewes at 40, 64 and 72 h and the variability in mean oFSH concentrations was greater (p < 0.05) in control ewes at 40, 48, 64 and 72 h after the 1st Folltropin®‐V injection. There were no differences (p > 0.05) between the two groups in serum concentrations of pFSH. Significant correlations were recorded between the number of corpora lutea (CL) and oFSH concentrations at 8 h (r = 0.72, p < 0.05), 16 h (r=0.63, p < 0.05) and 64 h (r = 0.84, p < 0.01) after the 1st Folltropin®‐V injection. The total number of recovered embryos was positively correlated to oFSH concentrations at 56 h (r = 0.69, p < 0.05). We concluded that changes in endogenous FSH concentrations during ovarian superstimulation with pFSH might contribute to the variability in superovulatory responses in ewes. 相似文献
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MA Hayes BA Quinn ND Keirstead P Katavolos RO Waelchli KJ Betteridge 《Reproduction in domestic animals》2008,43(S2):232-237
A critical period of early gestation in the mare involves the immobilization (fixation) of the encapsulated conceptus at around days 16–17. We compared the major proteins in the normal equine embryonic capsule and endometrial secretions around the period of fixation with those from pregnancies in the process of termination induced by administration of an analogue of prostaglandin F2α (PGF2α ). Uterocalin and β2 -microglobulin (β2 M) associated with the embryonic capsule were proteolytically converted to smaller forms during the fixation period. These conversions were similar in conceptuses from control and treated mares. A 17 kDa cationic protein identified as a secretory phospholipase A2 (sPLA2) type IIA was detected bound to normal capsules but increased substantially in response to PGF2α . Two forms of uteroglobin were distinguished by partial amino acid sequences of ∼6 kDa bands in flush fluids from normal pregnant uteri. After administration of PGF2α one immunoreactive form of uteroglobin was preferentially increased. These studies demonstrate that failure of pregnancy in this model is associated with an increase in secretory phospholipase in the capsule and a change in the forms of uteroglobin in the uterine secretions. 相似文献
119.
Summary
Current projects of biological control of introduced forest insects. (Third report on the activities of the European Station, Commonwealth Institute of Biological Control).The report covers the period of 1965 to 1970 dealing briefly with nine forest pests of European origin introduced into North America or East Africa. Research in Europe on the natural enemies of these pests is described and the present status of biological control operations is dicussed. The pest species dealt with are: the larch sawfly (Pristiphora erichsonii Htg.), the European pine sawfly (Neodiprion sertiferGeoff.), the birch leaf-mining sawfly (Fenusa pusilla Lep.), the birch case-bearer (Coleophora fuscedinella Hb.), the larch case-bearer (Coleophora laricella Zell.), the pine shoot moth (Rhyacionia buoliana Den. & Schiff.), the elm bark beetle (Scolytus multistriatus Marsh.) and the woolly aphidsDreyfusia piceae Ratz. andPineus spp. 相似文献
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