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51.
讨论干燥参数及物性参数,建立其关系式;给出表示颗粒农产品深床干燥特性的诸解析式;采用计算方法,示出解析结果以及这一方法的应用  相似文献   
52.
The exposure of freesia corms to ethylene (C2H4) at ca. 10 μl/l air for only 5 h was sufficient to promote sprouting, either under a closed system in which corms were treated in a sealed space of 3–10 1 or under a flow system in which corms were exposed to a continuous flow of air containing C2H4. Under the closed system, little change in corm response to C2H4 was found with increasing duration of exposure from 5 to 48 h, and the C02 concentration reached nearly 4% after 48 h. On the other hand, under the flow system, in which CO2 did not accumulate above 0.1%, the promotive effect of C2H4 was diminished by extended exposure from 5 to 48 h.Repeated treatment with C2H4 for 23 h daily on 4 successive days resulted in the lowering of the promotive effect as compared with a single treatment, but repeated application of C2H4 for 5 h daily showed the same effect as a single application and gave a high sprouting rate similar to smoke treatment, independent of ambient temperature ranging from 25 to 35° C.Corms exposed to C2H4 for 5 h daily, or to smoke for 4 days, exhibited a better chilling response and advanced flowering.  相似文献   
53.
We investigated the profiles of circulating levels of inhibin A and total inhibin in beef cows with follicular cysts in relation to the patterns of follicular development and circulating gonadotropins and steroid hormones. Turnover of follicular waves was monitored in five cows every 2 days for 70 days from 10 days after detection of estrus without ovulation. The mean interwave intervals were 19.6 ± 1.0 days (n = 18 waves with cysts from the five cows). Circulating levels of inhibin A were approximately 170 pg/ml before emergence of follicular waves with cysts and increased (P < 0.05) concomitantly with follicle emergence. High concentrations of inhibin A (greater than 300 pg/ml) were noted for 7 days during the growth phase of cystic follicles, but inhibin A levels decreased gradually when development of the cysts reached a plateau. This profile of inhibin A was similar to those of total inhibin and estradiol, but was inversely related to the changes in plasma FSH concentrations. LH pulse frequency and mean concentrations of LH in cows with cysts were higher than those observed in the luteal phase of normal cyclic cows. These results indicate that the capacity to secrete inhibin, as well as estradiol, is maintained in cystic follicles, the growth of which is extended by LH secretion at levels greater than those seen in the normal luteal phase. Inhibin A plays an important role in the extension of interwave intervals by suppressing recruitment of a new cohort of follicles.  相似文献   
54.
Decreased apoptotic polymorphonuclear leukocyte rate in dogs with pyometra   总被引:1,自引:0,他引:1  
Polymorphonuclear neutrophil (PMN) apoptosis was examined in three dogs with pyometra by TUNEL assay in a 24-hr incubation period and compared with that in healthy control dogs (n=5). The incidence of apoptotic PMNs in dogs with pyometra was 26.4 +/- 5% and that in healthy dogs was 54.3 +/- 7%. The results indicated that apoptotic PMN rates in dogs with pyometra were significantly lower than those in control dogs (p<0.05), suggesting the prolongation of PMN survival.  相似文献   
55.
We investigated the efficacy of a controlled internal drug release (CIDR) device in the reproductive management of an embryo donor beef herd. Superovulation of embryo donors was routinely induced by a combination of FSH and prostaglandin F(2)alpha analogue (PGF(2)alpha) at intervals of a few months, and after embryo recovery estrus of the donors was synchronized with PGF2(2)alpha. Between 1996 and 1998, approximately 20% of donors were diagnosed as having follicular cysts every year. Twenty-eight cases of follicular cysts recorded between 1997 and 1998 were treated with a CIDR device for 14 days to evaluate the efficacy of CIDR in resolving follicular cysts in donor herds. Initial recovery was defined as the occurrence of ovulation with estrous behavior and subsequent formation of a corpus luteum after removal of the CIDR. Initial recovery was recognized in all cases (n=28). Follicular cysts did not recur after repeated embryo recovery in 64% of the initially recovered donors, but in 36% of affected donors cysts recurred after the next embryo recovery. Subsequently, with a CIDR device instead of PGF(2)alpha, we synchronized estrus after embryo recovery in the same herd from 1999 to 2000, to investigate the ability of CIDR to prevent the initiation of follicular cysts. Of the donors used between 1999 and 2000, approximately 30% had a history of follicular cysts. Use of CIDR for estrous synchronization after embryo recovery lowered the incidence of follicular cysts to 3% in 1999 and 0% in 2000. Treatment with CIDR proved effective at resolving follicular cysts in the embryo donor beef herd and enabled re-use of donors affected with follicular cysts. CIDR is also likely to be efficacious in lowering the occurrence of follicular cysts in donor herds when it is used for estrous synchronization after embryo recovery.  相似文献   
56.
57.
Hemoglobin aggregation in single red blood cells of sickle cell anemia   总被引:6,自引:0,他引:6  
A laser light scattering technique was used to observe the extent of hemoglobin aggregation in solitary red blood cells of sickle cell anemia. Hemoglobin aggregation was confirmed in deoxygenated cells. The light scattering technique can also be applied to cytoplasmic studies of any biological cell.  相似文献   
58.
59.
Extensive and deep root systems have been recognized as one of the most important traits for improving chickpea (Cicer arietinum L.) productivity under progressively receding soil moisture conditions. However, available information on the range of variation for root traits is still limited. Genetic variability for the root traits was investigated using a cylinder culture system during two consecutive growth seasons in the mini-core germplasm collection of ICRISAT plus several wild relatives of chickpea. The largest genetic variability was observed at 35 days after sowing for root length density (RLD) (heritability, h 2 = 0.51 and 0.54) across seasons, and followed by the ratio of plant dry weight to root length density with h 2 of 0.37 and 0.50 for first and second season, respectively. The root growth of chickpea wild relatives was relatively poor compared to C. arietinum, except in case of C. reticulatum. An outstanding genotype, ICC 8261, which had the largest RLD and one of the deepest root system, was identified in chickpea mini-core germplasm collection. The accession ICC 4958 which was previously characterized as a source for drought avoidance in chickpea was confirmed as one with the most prolific and deep root system, although many superior accessions were also identified. The chickpea landraces collected from the Mediterranean and the west Asian region showed a significantly larger RLD than those from the south Asian region. In addition, the landraces originating from central Asia (former Soviet Union), characterized by arid agro-climatic conditions, also showed relatively larger RLD. As these regions are under-represented in the chickpea collection, they might be interesting areas for further germplasm exploration to identify new landraces with large RLD. The information on the genetic variability of chickpea root traits provides valuable baseline knowledge for further progress on the selection and breeding for drought avoidance root traits in chickpea.  相似文献   
60.
In leaves pretreated with an indole derivative [indole-3-acetic acid (IAA) tryptamine, or tryptophan], blast lesion formation was suppressed compared to those treated with distilled water (DW) as a control. Phenylalanine ammonia-lyase (PAL) activity and PAL expression were significantly enhanced in the IAA- or tryptophan-pretreated leaves, but not in tryptamine-pretreated leaves. This induction of resistance was inhibited by pretreatment with a PAL inhibitor, α-aminooxyacetic acid, in IAA- and in tryptophan-treated leaves, but not in tryptamine-treated leaves. This study strongly shows that the indole derivatives IAA tryptamine and tryptophan can enhance a disease resistance mechanism that is supported by different metabolic pathways.  相似文献   
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