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681.
Summary We have confirmed that the LLA-15 polypeptide ofLilium longiflorum is (a) tapetum specific with some expression possible in the adjacent middle layer cells and (b) relatively abundant as evidenced by the high density of gold particles localized to the tapetal cells. We have established that the protein is cytoplasmic and not associated with organelles, membranes, extracellular matrix or wall. We also report an amino acid composition of the molecule and a partial sequence which bears no resemblance to any protein yet described.Abbreviations BSA bovine serum albumin - PMSF phenyl methyl sulfonyl fluoride  相似文献   
682.
The dimeric and monomeric forms of the acetylcholine receptor from Torpedo californica electroplax have been purified in the presence of lipids and reconstituted. A spectroscopic method was applied to study the rapid kinetics of cation transport mediated by each of the reconstituted AcChR oligomers. Both the AcChR dimer and monomer responded to carbamylcholine by mediating cation transport on the time scale of a few milliseconds. The responses to carbamylcholine were blocked by histrionicotoxin and by desensitization, demonstrating that both forms manifest pharmacological properties observed in vivo. Analysis of the fast ion transport produced by various agonist concentrations yielded estimated rates of transport through a single receptor channel. These were comparable for the monomer and dimer and in agreement with those obtained for a preparation containing a mixture of both oligomers.  相似文献   
683.
Fallows improve soil fertility and allow sustainable agriculture. Soil fertility was assessed under different types of fallow through pH, nutrient concentrations and particulate organic matter (POM) quantity and quality. The two year-fallows were under Chromolaena odorata, Calliandra calothyrsus and Pueraria phaseoloides on a Typic Kandiudult. Soils were sampled from 0–10 cm and 10–20 cm depth. The weight of POM was 2 mg g−1 of soil under Calliandra, 3.9 mg g−1 under Chromolaena and 3.7 mg g−1 under Pueraria in the 0–10 cm layer. The tPOM-C (proportion of C in the total POM) and tPOM-N (proportion of N in total POM) were 26.1% and 14.5% under Calliandra, 39.6% and 18.8% under Chromolaena and 37.0% and 16.7% under Pueraria. However, despite the improvement of soil fertility under Pueraria as compared to planted Calliandra, the effect of Pueraria on nutrient concentration and POM status remained similar to that of Chromolaena. Calliandra increased soil acidity and allowed a deterioration of nutrient concentration (Ca, K), ECEC and an impoverishment of POM status.  相似文献   
684.
In this study, we analyzed 93 whole genomes from Chinese spot-billed ducks (CSB), meat-type ducks (MET), and egg and dual purpose-type ducks (EDT) to characterize the genetic material flowing between the CSB and modern ducks. Using a frequency of shared identical-by-descent method, approximately 10.9 Mb introgression segments containing 140 genes were identified showing the signatures of introgression between CSB and EDT. Meanwhile, nearly 10.6 M introgression regions containing 149 genes were identified between CSB and MET. Based on the haplotypes tree of each segment, we found that the introgression between CSB and domesticated ducks was asymmetric with a high level of gene flow from domestic to CSB and a low level of migration in the opposite direction. Moreover, we identified several genes that were introgressions from CSB and showed the signature of positive selection, which may contribute to the breeding of modern ducks. Our results provide new insight into the evolution and breeding history of domestic ducks and may be useful for the future management of wild and domestic duck populations.  相似文献   
685.
Summary Human alcohol dehydrogenase ADH2 and ADH3 were investigated in liver and stomach specimens of Chinese and Indians from West Malaysia. Eight-nine percent of the Chinese carry the atypical ADH2 type, a proportion very similar to that reported in Japanese. However, among 43 Indian specimens there was not a single case of atypical ADH2. In Indians, the gene frequency of ADH3 1 is 0.64 and of ADH3 2 0.36, similar to the frequencies in Caucasians, whereas in Chinese, the gene frequency for ADH3 1 and ADH3 2 is 0.91 and 0.09, respectively. We also report some unusual enzymatic characteristics in the course of our study.  相似文献   
686.
What information should be provided to a female patient suffering from a psychotic disorder or a bipolar disorder prior to the birth of her child? Pregnancy is a time of intense psychological reshuffles that may weaken parents-to-be. The couple or the mother-to-be will seek the support of their loved ones. In this particular time, the involvement of professionals may be necessary when difficulties arise for the couple in relation to the psychological adjustment required by a child??s arrival. In case of a pregnancy contemplated in women affected by a mental illness, information related to potential risks carried by treatments and also by the impact of the pregnancy itself, the eventuality of the inability, for a more or less long period of time, to look after the child as well as the occurrence of possible distortions of the interactions in this context must be discussed in each parental project. This consists of a reflection on the benefits/risks by the patient, if possible her partner, also involving the referring psychiatrist, the general practitioner, the obstetricians and the paediatricians. This information is not always easy for the referring psychiatric to deliver. A tight cooperation between the Department of General Psychiatry and the Departments of Infant-Juvenile Psychiatry is important from a perspective of prevention, as it is required to deal with the perinatal/prenatal issues which arise out of the formation of a quality bond between mentally ill parents and a baby, that is sometimes difficult to set in place by the professionals involved and also by the patients themselves at the time of the birth. Thus, Cico was set up at the Saint Anne Hospital, non sectored, dealing with child psychiatric and adult psychiatric approaches. It allows patients to reflect on their desire for a child and provides information on the course of pregnancy to patients. It also assesses the capacity of the patient to form a bond with the child.  相似文献   
687.
688.
In this paper, the authors propose a short overview of image fusion techniques in nuclear medicine. First, the methodological concepts of image fusion are discussed. Then, a sample of applications in nuclear medicine is presented. These applications ranging from diagnosis to guided therapy and monitoring clearly exemplify the challenges of image fusion in nuclear medicine.  相似文献   
689.
The applicability of a chlorophyll fluorescence assay for kanamycin (Km) resistance screening in transgenic tobacco (Nicotiana tabacum) and Arabidopsis thaliana plants was investigated. In wild-type leaves incubated in the presence of 200 mg/l Km, a decrease in maximum variable fluorescence ((Fv)m) and a significant increase in constant fluorescence (Fo) were observed. Using (Fv)m/Fo as a screening parameter, we were able to distinguish Km-treated samples from untreated samples within 4 days. This parameter was applied to Km resistance screening using tobacco plants transformed with the nptII gene via Agrobacterium. Among 74 shoots selected on medium containing 200 mg/l Km, 37 plants were scored as Km sensitive by the chlorophyll fluorescence assay. These 74 scorings proved to be accurate, as reconfirmed by (1) polymerase chain reaction amplification of the transgene, (2) enzymatic assay of neomycin phosphotransferase and (3) leaf disc assay. Using the chlorophyll fluorescence assay, we could also screen 3-week old Arabidopsis plants carrying the nptII gene. These results clearly demonstrate the reliability and efficiency of this nondestructive assay for Km resistance screening of transgenic plants. Received: 27 November 1995 / Revision received: 18 April 1997 / Accepted: 28 July 1997  相似文献   
690.
 The report describes a system for somatic embryogenesis and direct plant regeneration from the embryos of Manihot glaziovii. Somatic embryos were obtained by culturing young leaf lobes (3–6 mm long) adjacent to the apex in Murashige and Skoog medium containing 18 μm 2,4-dichlorophenoxy acetic acid for 20 days and then transferring them to a maturation medium with 0.5 μm 6-benzylaminopurine. Secondary embryogenesis was induced from cotyledonary segments of somatic embryos by using the same protocol as that for primary embryogenesis. For regeneration, somatic embryos were cultured in medium supplemented with 10−4m kinetin and 53.4% of them developed into plantlets. Linamarin and linamarase were not detected in calli or in somatic embryos. Linamarin content was found to be highest in leaves of regenerated plantlets, followed by stem and root tissues. Levels of linamarase activity were almost the same in leaves and stem tissues and very low in roots. Received: 19 April 1999 / Revision received: 11 August 1999 / Accepted: 17 August 1999  相似文献   
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