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71.
Mackay DA 《Science (New York, N.Y.)》1927,65(1688):446-447
These experiments would seem to prove that no special spiracles are used for inhaling and others used for exhaling, but rather that all are alike in this respect, as the abdomen expands air is taken in and as the body contracts the gases are exhaled. 相似文献
72.
H. I. Schiff G. I. Mackay C. Castledine G. W. Harris Q. Tran 《Water, air, and soil pollution》1986,30(1-2):105-114
A highly sensitive, lightweight, portable instrument has been developed for continuous monitoring of N02 in air. It operates by detecting the chemiluminescence produced when N02 encounters a surface wetted with a specially formulated solution containing luminol. Unlike other chemiluminescent instruments it measures N02 directly and does not require prior conversion of N02 to NO. It does not respond to H202, NO, HNO3, NH3, CO, C02, S02 or organic nitrates. The only interferences encountered to date are from 03 and PAN with the response to 03 being less than 0.2% of its response to N02. The response time of the instrument is less than 1 s and its sensitivity is better than 5 pptv. The instrument shows a negative temperature dependence of about 2% °C?1 which is compensated electronically. Measurements have been made with the instrument during a number of field missions in polluted urban and relatively clean rural air. The relative influences of photochemistry and transport from local sources has been observed. Simultaneous measurements made with this instrument and the unequivocal tunable diode laser absorption spectroscopy method have shown excellent agreement. 相似文献
73.
Summary This paper reviews investigations into the application of protoplast fusion to the genetic and agronomic improvement of potato. Fusion studies involving Solanum tuberosum are reviewed under the categories of: fusion with wild relatives, dihaploid fusion and asymmetric strategies. The selection and characterisation of putative somatic hybrid material is identified as a critical stage in the process and certain specific aspects of this technology are identified. Future prospects for the wider uptake and integration of these techniques into breeding programmes are also discussed. 相似文献
74.
75.
The efficiency of between and within family selection in a full-sib family recurrent selection programme was investigated
using data from three cycles of recurrent selection. Correlations between mid-parent values and offspring were high for sugar
content and juice purity characters, but low for root weight and sugar yield. This suggests that single root selection within
full-sib families is effective in the improvement of sugar content and juice purity, but ineffective for root weight and sugar
yield. Root weight and sugar yield will respond better to between full-sib family selection.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
76.
NS Matthews SW Erickson GS Light MR Slater SM Hartsfield 《Veterinary anaesthesia and analgesia》1995,22(1):25-30
The effects of tolazoline (4.0 mg/kg iv) antagonism of detomidine (0.02 mg/kg iv) were evaluated in isoflurane-anaesthetised, ventilated ponies. Each of 6 ponies received both tolazoline and saline treatment during separate anaesthetic episodes only (no surgery was performed). Detomidine administration produced an increase in blood pressure, decrease in heart rate and decrease in PaO2 Tolazoline treatment transiently increased heart rate while blood pressure returned to baseline after both treatments. Arterial oxygenation decreased further after tolazoline treatment while oxgenation recovered towards baseline with saline treatment. No other cardiopulmonary effects were detected. Recovery from anaesthesia tended to be more rapid when detomidine was antagonized. The potential benefit of antagonizing detomidine-induced bradycardia with tolazoline, during isoflurane anaesthesia should be weighed against the potential to produce a decrease in arterial oxygenation. The mechanism for this effect is not clear. 相似文献
77.
KC Silva‐Santos GMG Santos C Koetz Júnior F Morotti LS Siloto TN Marcantonio MR Urbano RL Oliveira DCM Lima MM Seneda 《Reproduction in domestic animals》2014,49(2):228-232
Interest in indicus–taurus cattle has been increasing, as these animals are likely to present the best characteristics of Zebu and European bovine breeds. The aim of this study was to compare the embryo production of indicus–taurus donors with high vs low antral follicle counts obtained by ovum pickup/in vitro production (OPU/IVP) and superovulation (SOV)/embryo collection. Braford females at weaning age (3/8 Nelore × 5/8 Hereford, n = 137, 9 ± 1 month old) were subjected to six serial ovarian ultrasonographs and were assigned to two groups according to the number of antral follicles ≥3 mm as follows: G‐High antral follicular count (AFC, n = 20, mean ≥40 follicles) and G‐Low AFC (n = 20, mean ≤10 follicles). When the females (n = 40) reached 24 months of age, they were subjected to both OPU/IVP and SOV/embryo collection. The average number of follicles remained highly stable throughout all of the ultrasound evaluations (range 0.90–0.92). The mean number of COCs recovered (36.90 ± 13.68 vs 5.80 ± 3.40) was higher (p < 0.05) for females with high AFC, resulting in higher (p < 0.05) numbers of total embryos among females with high vs low AFC (6.10 ± 4.51 vs 0.55 ± 0.83). The mean number of embryos per collection was also higher (p < 0.05) for G‐High vs G‐Low (6.95 ± 5.34 vs 1.9 ± 2.13). We conclude that a single ultrasound performed at pre‐pubertal ages to count antral follicles can be used as a predictor of embryo production following IVP and SOV/embryo collection in indicus–taurus females. 相似文献
78.
The farrowing rates resulting from matings on different days of the week were determined for a 2800-sow intensive piggery in both 1983 and 1984. The results showed that sows mated early in the week achieved a significantly higher farrowing rate than sows mated late in the week (P less than 0.0001). During the seasonal (summer to autumn) infertility period, Wednesday matings resulted in a poor farrowing rate whereas for the rest of the year farrowing rates following Wednesday matings were similar to those for Sunday Monday and Tuesday matings. Consistent results were obtained for data from both years. It is proposed that the stress of regrouping unmated sows on Wednesday to accommodate newly weaned sows is responsible for this decrease in fertility. This study illustrates how detailed analysis of farrowing rates on a day of mating basis can identify a problem which is otherwise masked by weekly data. 相似文献
79.
CASE HISTORY An 18-month clinical course of chronic ill-thrift, weight loss and emaciation, and eventual death occurred in a group of 520 translocated elk of mixed age and sex. Trans-location was carried out without regard to animal welfare or health risks associated with the translocation. Mortality was approximately 84% (436/520) despite supportive nutritional and medical treatment. PATHOLOGICAL FINDINGS: General clinical and post-mortem examinations indicated only Se and Cu imbalances and nutritional inadequacy. Additional purposeful post-mortem examination and histological evaluation of tissue sections from four of the affected adult elk demonstrated elevated abomasal pH and proliferative abomasal lesions as the most significant findings, consistent with Type-II ostertagiosis; intra-lesional nematodes were seen in the abomasum of two animals. DIAGNOSIS: Fading elk syndrome, or abomasal parasite syndrome in elk. CLINICAL RELEVANCE: Abomasal parasite syndrome initiated by Type-II ostertagiosis should be considered as a differential diagnosis in cases of ill-thrift and wasting in elk or elk-red deer hybrids. Changes to the architecture and secretory function of the abomasal wall lead to apparently irreversible digestive pathophysiology and nutritional disease. 相似文献
80.