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111.
The metal content of bryophytes (Fontinalis antipyretica), invertebrates (Asellus aquaticus, Sialis lutaria, Libellulidae) and fish (Perca fluviatilis, Esux lucius) was measured along an aquatic concentration gradient of Zn, Cu, Cd, Pb, As, Hg, generated by air emissions from the Rönnskär smelters. The separation of pH effects on metal uptake, was facilitated by metal and pH vectors being mostly well separated from each others. The interpretation was facilitated by seasonal small variations in water metal content, which improved the calculation of bioconcentration factors (BCF) as a strict measure of bioavailability. It was found that BCF varied as function of element and taxon. When pH decreased, BCF also did so for Zn, Cd, Ni, Co in bryophytes, while BCF increased for Pb, Cu in in fish. We conclude and agree that one-sided focusing on total concentrations may overlook shifts in speciation due to pH in moderately acidified waters for elements like Cu and Pb.  相似文献   
112.
Dust plumes were generated by farm equipment during standard field preparations and harvest operations. Light detection and ranging (lidar) measurements of dust particle concentrations in the plumes were censored by an upper detection limit. The nonstandardized Gaussian curve, with range values as the argument, was used as a model for the one-dimensional plume profile. Maximum likelihood estimates for the Gaussian plume equation were found in order to make inferences concerning plume characteristics.  相似文献   
113.
A post‐breeding migration of leucocytes (PMN) into the uterus is considered to be an important reason for sperm losses. Minimizing such effects may be necessary for successful insemination with low sperm numbers, as required with sex‐sorted spermatozoa. We examined the magnitude of PMN influx 3 h after pre‐ or post‐ovulatory insemination with various combinations of seminal plasma (SP), semen extender Androhep? (AH; Minitüb, Tiefenbach, Germany) and sperm preparations (S). Pre‐ovulatory inseminations with preparations containing 98% AH caused a massive influx of PMN, independent of whether spermatozoa were present (628 ± 189 × 106 leucocytes/uterine horn) or not (580 ± 153 × 106). Post‐ovulatory, 98% AH caused a comparable immigration only in the absence of sperm cells (AH: 569 ± 198 × 106, AH+S: 162 ± 102 × 106). The presence of SP significantly dampened the numbers of recruited uterine leucocytes. The reaction to all inseminates containing 98% SP both with and without spermatozoa, used before ovulation (SP: 14 ± 6 × 106, SP+S: 73 ± 27 × 106) and after ovulation (SP: 60 ± 32 × 106, SP+S: 51 ± 33 × 106) did not differ significantly from controls using phosphate buffered saline (PBS) (pre‐ovulatory: 1 ± 1 × 106, post‐ovulatory: 11 ± 9 × 106). Quantitative in vitro transmigration assays with blood‐derived PMN proved that AH‐induced leucocyte migration into the uterus to be not as a result of direct chemotaxis, because, on account of the chelator citrate, AH significantly inhibited the transmigration towards recombinant human Interleukin‐8 (rhCXCL8) (AH: 14 ± 5% migration rate vs controls: 37 ± 6%, p < 0.05). Supernatants of spermatozoa incubated in PBS for 1, 12 or 24 h showed neither chemoattractive nor chemotaxis‐inhibiting properties. SP at ≥0.1% [v/v] significantly inhibited the in vitro transmigration of PMN. With respect to in vivo migration of neutrophils, the striking difference in the results between semen extender and seminal plasma suggests that adaptation of extender composition is needed to reflect more closely the in vivo regulatory potential of natural seminal plasma.  相似文献   
114.
Abstract It is a challenge to obtain the appropriate protein concentration in cereals for the intended end‐use. This study examined ambient temperature effects on two spring malting barley cultivars (Henley and Tipple) grown in soil or in solution culture with controlled nitrogen supply in daylight chambers with low temperature (day 18 °C, night 12 °C), and high temperature (23 °C/17 °C) to/after anthesis. In soil‐grown plants, high temperature to anthesis resulted in higher grain nitrogen amount (GNA), grain nitrogen concentration (GNC) and straw nitrogen concentration (SNC). In plants grown in solution, high temperature to anthesis resulted in lower GNA and higher GNC. A temperature rise of 1 °C during the growing period in solution cultivation increased GNC, root nitrogen concentration (RNC) and SNC, by 1.20, 1.35 and 0.33 mg g?1, respectively. In solution culture, GNC was positively correlated with RNC and SNC (P < 0.01). Cv. Henley had higher GNC but lower SNC than cv. Tipple. Cv. Henley was more stable in grain size and cv. Tipple in GNC. The results showed that temperature has a direct effect on GNC. Accounting for temperature fluctuations up to the latest possible nitrogen fertilisation occasion can therefore help when deciding appropriate nitrogen supply for intended end‐use.  相似文献   
115.
116.
Acute pancreatitis in dogs   总被引:1,自引:0,他引:1  
Objective: To summarize current information regarding severity assessment, diagnostic imaging, and treatment of human and canine acute pancreatitis (AP). Human‐based studies: In humans, scoring systems, advanced imaging methods, and serum markers are used to assess the severity of disease, which allows for optimization of patient management. The extent of pancreatic necrosis and the presence of infected pancreatic necrosis are the most important factors determining the development of multiple organ failure (MOF) and subsequent mortality. Considerable research efforts have focused on the development of inexpensive, easy, and reliable laboratory markers to assess disease severity as early as possible in the course of the disease. The use of prophylactic antibiotics, enteral nutrition, and surgery have been shown to be beneficial in certain patient populations. Veterinary‐based studies: The majority of what is currently known about naturally occurring canine AP has been derived from retrospective evaluations. The identification and development of inexpensive and reliable detection kits of key laboratory markers in dogs with AP could dramatically improve our ability to prognosticate and identify patient populations likely to benefit from treatment interventions. Treatment remains largely supportive and future studies evaluating the efficacy of surgery, nutritional support and other treatment modalities are warranted. Data sources: Current human and veterinary literature. Conclusions: Pancreatitis can lead to a life‐threatening severe systemic inflammatory condition, resulting in MOF and death in both humans and dogs. Given the similarities in the pathophysiology of AP in both humans and dogs, novel concepts used to assess severity and treat people with AP may be applicable to dogs.  相似文献   
117.
Clinical, hematologic, and immunologic findings for 14 dogs with Ehrlichia canis monoclonal gammopathy were studied retrospectively. Epistaxis, anemia, thrombocytopenia, hypoalbuminemia, hypergammaglobulinemia, and proteinuria were documented in the majority of these dogs. The serum protein electrophoresis pattern was characterized by a distinct narrow-base monoclonal spike, by a broad-base monoclonal spike, or by a monoclonal spike superimposed on a polyclonal gammopathy. The monoclonal spike disappeared following tetracycline treatment for ehrlichiosis. The long-term prognosis following treatment was generally good. The diagnostic features of monoclonal gammopathy due to myeloma were compared with those of E. canis monoclonal gammopathy. Owing to numerous similarities in clinical, hematologic, and immunologic findings, we conclude that an E. canis antibody titer should be determined in all dogs in which a diagnosis of benign monoclonal gammopathy is contemplated or definitive evidence of myeloma, leukemia, or macroglobulinemia is lacking.  相似文献   
118.
Host-response patterns of intramammary infections in dairy cows   总被引:2,自引:0,他引:2  
Many different bacterial species have the ability to cause an infection of the bovine mammary gland and the host response to these infections is what we recognize as mastitis. In this review we evaluate the pathogen specific response to the three main bacterial species causing bovine mastitis: Escherichia coli, Streptococcus uberis and Staphylococcus aureus. In this paper we will review the bacterial growth patterns, host immune response and clinical response that results from the intramammary infections. Clear differences in bacterial growth pattern are shown between bacterial species. The dominant pattern in E. coli infections is a short duration high bacteria count infection, in S. aureus this is more commonly a persistent infection with relative low bacteria counts and in S. uberis a long duration high bacteria count infection is often observed. The host immune response differs significantly depending on the invading bacterial species. The underlying reasons for the differences and the resulting host response are described. Finally we discuss the clinical response pattern for each of the three bacterial species. The largest contrast is between E. coli and S. aureus where a larger proportion of E. coli infections cause potentially severe clinical symptoms, whereas the majority of S. aureus infections go clinically unnoticed. The relevance of fully understanding the bovine host response to intramammary infection is discussed, some major gaps in our knowledge are highlighted and directions for future research are indicated.  相似文献   
119.
120.
Precise calving monitoring is essential for minimizing the effects of dystocia in cows and calves. We conducted two studies in healthy cows that compared seven clinical signs (broad pelvic ligaments relaxation, vaginal secretion, udder hyperplasia, udder edema, teat filling, tail relaxation, and vulva edema) alone and in combination in order to predict the time of parturition. The relaxation of the broad pelvic ligaments combined with teat filling gave the best values for predicting either calving or no calving within 12 h. For the proposed parturition score (PS), a threshold of 4 PS points was identified below which calving within the next 12 h could be ruled out with a probability of 99.3% in cows (95.5% in heifers). Above this threshold, intermitted calving monitoring every 3 h and a progesterone rapid blood test (PRBT) would be recommended. By combining the PS and PRBT (if PS ≥ 4), the prediction of calving within the next 12 h improved from 14.9% to 53.1%, and the probability of ruling out calving was 96.8%. The PRBT was compared to the results of an enzyme immunoassay (sensitivity, 90.2%; specificity, 74.9%). The standard operating procedure developed in this study that combines the PS and PRBT will enable veterinarians to rule out or predict calving within a 12 h period in cows with high accuracy under field conditions.  相似文献   
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