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91.
In humans it has been estimated that for each 2.5 g L–1 decrease in serum albumin, risk of death increases by 24–56%. Clinical impression suggests this may be similar in veterinary patients. Species‐specific albumin (plasma) is often unavailable and concentrated solutions are not. Our experience using 25% human serum albumin (HSA) in critically ill dogs suggests a positive effect (results submitted), however it is expensive. Bovine serum albumin (BSA) may be a more cost effective and readily available alternative. The purpose of this study was to assess the immediate and long‐term safety of an intravenous dose (500 mg kg–1) of bovine albumin administered to healthy dogs. Ten mature dogs (eight males, two females, 28 ± 6 kg) were to receive BSA (250 mg mL–1) twice (BSA1 and BSA2) with 14 days between treatments. Temperature, blood pressure, and pulse and respiration rate were continuously monitored to identify a reaction to BSA. All dogs received BSA1. One dog immediately developed mild urticaria and pruritus, otherwise the infusion was well tolerated. No immediate reaction was noted in the other nine dogs. Two dogs received BSA2. One dog developed a mild immediate reaction similar to that occurring with BSA1, and one dog (the dog immediately reacting to BSA1) developed a severe anaphylactic reaction. Due to these reactions, no other dogs received BSA2. During a two‐week observation of the remaining eight dogs given BSA1, five developed a mild or severe generalized type‐III hypersensitivity reaction. The dog experiencing a mild reaction during BSA2 administration also developed a generalized type‐III hypersensitivity reaction. Delayed reactions occurred 15 ± 2.7 days after BSA exposure. Three dogs did not develop a reaction. All reacting dogs recovered fully. The severity of reactions, and the number of dogs affected, suggests prior (natural) exposure and immunological sensitization to bovine albumin. Bovine serum albumin is not suitable for therapeutic use in dogs.  相似文献   
92.
The green iguana, Iguana iguana, is used as a model in reptile anesthesia research because of its size, availability, and the body of knowledge characterizing its physiology. Arterial blood gas values in nonanesthetized green iguanas have not been determined because of the technical difficulty involved. Vascular access port (VAP) placement to facilitate blood sampling has been described in other species, but not lacertilians. This abstract describes the technique for placement of VAPs and the values for arterial blood gas parameters in seven 1 kg adult green iguanas. Using sterile technique, a 1.5 cm incision was made on the lateral side of the neck. Blunt dissection ventral to the external jugular vein revealed the internal and external carotid arteries near their bifurcation. The catheter was inserted into the internal carotid artery and then guided to the common carotid artery. The other end of the catheter was tunneled below the skin to a subcutaneous location, caudal‐dorsal to the iSPSilateral scapula. The skin was closed and the port was flushed twice a week with heparinized saline. Post‐operatively, the VAPs were well tolerated by the iguanas. Difficulties included port disconnection (n = 1), inability to aspirate blood after a few weeks (n = 2), and infection (n = 1). The iguanas were breathing room air prior to and during blood collection. From the five functional VAPs, the blood pH, PCO2, PO2, HCO3, and BE (measured at 37 °C) were 7.45 ± 0.06; 37.5 ± 7.0 mm Hg, 99.0 ±16.6 mm Hg, 25.4 ± 2.5 mmol L–1, and 1.5 ±2.4 mmol L–1 respectively (mean ± SD). VAPs can be successfully used to facilitate collection of arterial blood gas samples in green iguanas. These values are similar to those reported for most mammalian species. This technique should facilitate research in anesthesiology and respiratory physiology of iguanas and other lacertilians.  相似文献   
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Objective— To describe a tenoscopic approach to the carpal sheath for desmotomy of the accessory ligament of the superficial digital flexor tendon. Study Design— The surgical procedure was developed with use of normal forelimbs from equine cadavers and experimental horses. Animals or Sample Population— Twelve equine cadaveric forelimbs, 4 forelimbs from 2 horses anesthetized for terminal surgical laboratories, and 10 forelimbs from five experimental horses were used. Methods— The limbs were positioned lateral side up with the carpus slightly flexed. After distention of the carpal sheath, a portal was made approximately 2 cm proximal to the distal radial physis for arthroscope insertion. An instrument portal was made approximately 0.2 cm proximal to the distal radial physis. After flexion of the limb to 90°, the accessory ligament of the superficial digital flexor tendon was palpated and desmotomy was performed. Cadaveric limbs were dissected to confirm complete desmotomy. Experimental horses were monitored for short- (perioperative) and long- (4 weeks) term postoperative complications. Results— A tenoscopic approach to the carpal sheath provided adequate surgical access to the accessory ligament of the superficial digital flexor tendon for desmotomy. Most of the accessory ligament of the superficial digital flexor tendon could be easily seen within the sheath, except for the proximal 2 cm that could be readily palpated and subsequently transected. Important technical considerations were location of the arthroscope portal, adequate sheath distention, limb flexion to 90°, and desmotomy location. It was beneficial, but apparently not essential, to avoid the proximal perforating vessel. Postoperatively, some horses had swelling but were not lame and had normal range of motion of the carpus. Conclusions— Desmotomy of the accessory ligament of the superficial digital flexor tendon could be performed by using a lateral tenoscopic approach to the carpal sheath. Clinical Relevance— Desmotomy of the accessory ligament of the superficial digital flexor tendon by using a tenoscopic approach to the carpal sheath is an alternative technique to the medial incisional approach.  相似文献   
96.
通过简化培养基成分,去除有机物,可抑制在长期继代培养中被茵类污染的试管苗;采用液体培养,可降低试管苗成本;用自然光代替日光灯,并结合黑暗培养,可减少设备投入,简化培养室条件,有利于工厂化育苗生产.  相似文献   
97.
Brazil nut (Bertholletia excelsa), has emerged as the cornerstone of the extractive economy in much of the Amazon, but the debate continues as to whether or not current harvest levels have a detrimental effect on Brazil nut seedling recruitment. While regeneration studies to date have been conducted solely within mature forest, our study provides further insight into current Brazil nut regeneration dynamics, with a unique first look at regeneration in swidden fallows within two multiple-use areas in Acre, Brazil. Recruitment of individuals ≤10 cm diameter at breast height (dbh) was evaluated within three 9 ha mature forest plots and six fallows of 0.5–1.0 ha each. Higher mean densities of B. excelsa seedlings (individuals <1.5 m in height) were observed in fallow than in mature forest (12.7 and 5.3 individuals ha−1, respectively). A generalized linear mixed model analysis revealed that in addition to forest type, proximity to seed sources also explained seedling densities. Height and diameter growth of young B. excelsa individuals was positively related to light availability. Photosynthetic photon flux density levels were over three times higher in fallows versus mature forest during peak sunlight hours. Results suggest that fallow environments may provide favorable conditions for B. excelsa regeneration. Not only can anthropogenic disturbance in the form of shifting cultivation play a positive role in B. excelsa regeneration, its historic presence on the landscape could explain current Brazil nut densities and distributions. Finally, swidden fallows could potentially be managed for enhanced Brazil nut densities, which may provide an opportunity for greater income for extractive families while contributing to the sustainability of Brazil nut extraction and forest conservation in the long term.  相似文献   
98.
美国黑核桃组织培养技术   总被引:19,自引:12,他引:7  
采用组织培养方法对美国黑核桃进行组织培养研究。结果表明:获得外植体的最佳方法是用新鲜且经层积处理的种子育苗.再用其实生苗的顶芽或茎段;适合黑核桃茎尖(段)培养的培养基为1/2MS(、其中大量元素用量减半,微量元素用量不变).且培养基中其他物质的含量为.VB15mg/L.VB62mg/L.烟酸2mg/L.腺素2mg/L.肌醇按1/2MS量.6-BA1.5mg/L.NAA0.05mg/L;外植体接种用流水冲洗.适当缩短转瓶周期(每10~l5d转瓶一次).可减轻褐变现象。  相似文献   
99.
ABSTRACT

Aims: To determine the presence of infection and co-infection of Plasmodium lineages in introduced birds at translocation sites for the North Island saddleback (Philesturnus rufusater), to investigate their role as Plasmodium spp. reservoirs.

Methods: Blood samples were collected from introduced bird species, with a special focus on blackbirds (Turdus merula) and song thrushes (Turdus philomelos), at six locations in the North Island of New Zealand that were the origin, or translocation sites, for North Island saddleback. Where available, blood smears were examined, and blood samples were tested using nested PCR with subsequent sequence analysis, for the presence of Plasmodium spp.

Results: Of the 55 samples tested using PCR analysis, 39 (71%) were positive for Plasmodium spp., and 28/40 (62%) blood smears were positive for Plasmodium spp. Overall, 31 blood samples were from blackbirds with 28/31 (90%) samples positive for Plasmodium spp. Six distinct avian Plasmodium lineages were identified, including three cosmopolitan lineages; Plasmodium vaughani SYAT05 was detected in 16 samples, Plasmodium matutinum Linn1 in 10 samples and Plasmodium elongatum GRW6 in eight samples. Mixed infections with more than one lineage were detected in 12 samples. Samples from two Australian magpies (Gymnorhina tibicen) were positive for Plasmodium. sp. lineage MYNA02, previously not identified in New Zealand.

Conclusions and clinical relevance: This is the first report from New Zealand in which specific Plasmodium spp. mixed infections have been found in introduced birds. Co-infections with several cosmopolitan Plasmodium lineages were identified, as well as the first report in New Zealand of an exotic avian Plasmodium sp. lineage, in Australian magpies. Whilst the role of introduced birds in maintaining and spreading pathogenic avian malaria in New Zealand is unclear, there is a potential infection risk to native birds, especially where distributions overlap.  相似文献   
100.
The South Equatorial Counter Current (SECC) strongly influences the American Samoa Exclusive Economic Zone (EEZ) and changes strength on a seasonal and ENSO cycle. A strong SECC is associated with a predominantly anticyclonic eddy field as well as increased micronekton biomass and catch-per-unit-effort (CPUE) for albacore tuna, the economically important target species of the local longline fishery. A strong SECC carries chlorophyll a -rich waters from upwelling regions at the north coast of New Guinea towards the EEZ, most likely resulting in the observed increase in micronekton biomass, forage for albacore. Relatively stable anticyclonic eddies show a further increase in micronekton biomass, apparently advected from neighboring SECC waters. The presence of forage presumably concentrates albacore, thus resulting in the observed increase in CPUE. High shear regions of neither anticyclonic nor cyclonic eddies correlate with increased micronekton biomass. Areas characterized by South Equatorial Current (SEC) waters correspond to areas with the lowest micronekton biomass and the highest number of aggregative structures, which are most likely small pelagic fish shoals. Micronekton composition in SEC waters differs from that in the SECC. During El Niños, the seasonal signals at the north shore of New Guinea and in the SECC are exceptionally strong and correspond to higher albacore CPUE in the EEZ. My results suggest that the strength of upwelling and the resulting increase in chlorophyll a at New Guinea, as well as the Southern Oscillation Index, could be used to predict the performance of the local longline fishery for albacore tuna in the American Samoa EEZ.  相似文献   
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