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Summary DNA sequences of the human, mouse, and rabbit immunoglobulin kappa-gene (J-C regions) are compared with respect to various DNA patterns, including dyad symmetry pairings, runs of nucleotides, repeat clusters, and repeats that occur with unusually high frequency. The significant dyad symmetry pairings within each of the sequences emphasize the two control-enhancer elements of the J5-C intron. Dyad symmetry pairs between the J-C region and a number of kappa variable (V)-gene domains suggest differences in the affinities between the V and J segments. It is the consensus heptamer rather than the consensus nonamer that embodies the longest V-J dyad symmetry combinations. In the rabbit there are long runs and repeat clusters of the sequences that identify regions of high duplication; these regions are absent in the human and mouse sequences. High-frequency oligonucleotides feature the consensus nonamer 5 to the J segments, especially in the mouse sequence.  相似文献   
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Background

Systemic sclerosis, or scleroderma, is a chronic and rare connective tissue disease with negative physical and psychological implications. Sources of emotional distress and the impact they have on the lives of people with scleroderma are not well understood.

Objectives

To gain an in-depth understanding of the emotional experiences and sources of emotional distress for women and men living with scleroderma through focus group discussions.

Methods

Three semi-structured focus group discussions were conducted (two in English, one in French) with a total of 22 people with scleroderma recruited through the Scleroderma Society of Ontario in Hamilton, Ontario and a scleroderma clinic in Montreal, Canada. Interviews were recorded, transcribed, and then coded for emerging themes using thematic inductive analysis.

Results

Core themes representing sources of emotional distress were identified, including: (a) facing a new reality; (b) the daily struggle of living with scleroderma; (c) handling work, employment and general financial burden; (d) changing family roles; (e) social interactions; and (f) navigating the health care system. Collectively, these themes refer to the stressful journey of living with scleroderma including the obstacles faced and the emotional experiences beginning prior to receiving a diagnosis and continuing throughout the participants’ lives.

Conclusion

Scleroderma was portrayed as being an unpredictable and overwhelming disease, resulting in many individuals experiencing multiple sources of emotional distress. Interventions and supportive resources need to be developed to help individuals with scleroderma and people close to them manage and cope with the emotional aspects of the disease.  相似文献   
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Plutella xylostella is an important pest of cruciferous crops worldwide. However, information regarding the age‐stage, two‐sex life parameters of P. xylostella, which is vital for designing more effective control methods, is currently lacking. The present study reports age‐stage, two‐sex life table parameters for P. xylostella on napa cabbage (Brassica oleracea var. napa), white cabbage (B. oleracea var. capitata), and cauliflower (B. oleracea var. botrytis) under laboratory conditions at 25 ± 2°C, 50–60% relative humidity, and a 16‐h light : 8‐h dark photoperiod. The time for development from an egg to a male or female adult P. xylostella on white cabbage (mean [± SE] 41.15 ± 0.54 and 39.50 ± 0.54 days, respectively) was significantly longer than that on cauliflower and napa cabbage. Furthermore, P. xylostella fecundity on cauliflower (261.90 ± 4.53 eggs female) was significantly highest than on napa cabbage and white cabbage. Intrinsic rate of increase (r) and finite rate of increase (λ) were highest on cauliflower 0.182 day?1 and 1.199 day?1 respectively as comparison to napa cabbage and white cabbage. The highest gross reproductive rate (GRR) and net reproductive rates (R0) of P. xylostella 65.87 and 52.58 respectively on cauliflower then those of other hosts. The findings of the present study indicate that cauliflower is the most suitable cultivar (host) for the development of P. xylostella. Based on these findings, crops like cauliflower can be used as trap crops when napa cabbage and white cabbage are the main crops.  相似文献   
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Dear Editor, Hepatocellular carcinoma (HCC) is the second most deadly cancer worldwide.1 Cirrhosis of different causes predisposes patients to HCC,increasing th...  相似文献   
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The detailed mechanical properties of various layers of the coronary artery are important for understanding the function of the vessel. The present article is focused on the determination of the incremental modulus in different layers and directions in the neighborhood of the in vivo state. The incremental modulus can be defined for any material subjected to a large deformation if small perturbations in strain lead to small perturbations of stresses in a linear fashion. This analysis was applied to the porcine coronary artery, which was treated as a two-layered structure consisting of an inner intima-media layer and an outer adventitia layer. We adopted a theory based on small-perturbation experiments at homeostatic conditions for determination of incremental moduli in circumferential, axial, and cross directions in the two layers. The experiments were based on inflation and axial stretch. We demonstrate that under homeostatic conditions the incremental moduli are layer- and direction dependent. The incremental modulus is highest in the circumferential direction. Furthermore, in the circumferential direction, the media is stiffer than the whole wall, which is stiffer than the adventitia. In the axial direction, the adventitia is stiffer than the intact wall, which is stiffer than the media. Hence, the coronary artery must be treated as a composite, nonisotropic body. The data acquire physiological relevance in relation to coronary artery health and disease.  相似文献   
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The branching pattern of the coronary arteries and veins is asymmetric, i.e., many small vessels branch off of a large trunk such that the two daughter vessels at a bifurcation are of unequal diameters and lengths. One important implication of the geometric vascular asymmetry is the dispersion of blood flow at a bifurcation, which leads to large spatial heterogeneity of myocardial blood flow. To document the asymmetric branching pattern of the coronary vessels, we computed an asymmetry ratio for the diameters and lengths of all vessels, defined as the ratio of the daughter diameters and lengths, respectively. Previous data from silicone elastomer cast of the entire coronary vasculature including arteries, arterioles, venules, and veins were analyzed. Data on smaller vessels were obtained from histological specimens by optical sectioning, whereas data on larger vessels were obtained from vascular casts. Asymmetry ratios for vascular areas, volumes, resistances, and flows of the various daughter vessels were computed from the asymmetry ratios of diameters and lengths for every order of mother vessel. The results show that the largest orders of arterial and venous vessels are most asymmetric and the degree of asymmetry decreases toward the smaller vessels. Furthermore, the diameter asymmetry at a bifurcation is significantly larger for the coronary veins (1.7-6.8 for sinus veins) than the corresponding arteries (1.5-5.8 for left anterior descending coronary artery) for orders 2-10, respectively. The reported diameter asymmetry at a bifurcation leads to significant heterogeneity of blood flow at a bifurcation. Hence, the present data quantify the dispersion of blood flow at a bifurcation and are essential for understanding flow heterogeneity in the coronary circulation.  相似文献   
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