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1.
Abstract:  The influence of four abiotic factors (temperature, soil type, compaction, moisture) on the pupation depth of the wild Bactrocera ( Dacus ) oleae (Gmel.) larvae was studied using soils sampled in the field. Two temperatures (25 and 12°C), three different soil types (alluvial deposits, soil from decaying of limestone, soil from decaying of flysch), two compaction levels (low and high) and two moisture levels (10 and 50% field capacity) were tested in a factorial experiment with a total of 96 experimental units. Five larvae were placed on the soil surface of each test container and when burrowing was completed pupae were retrieved and pupation depth was recorded. The majority of larvae pupated in the top 3 cm and the mean depth of all units was 1.16 cm. The means differed significantly depending on soil type, moisture, the temperature–soil type interaction and the soil type–moisture interaction. Larvae pupated at a greater depth in limestone than in the other two soils. Depths were greater in soils at 50% field capacity than in those at 10% field capacity. In limestone and flysch the depth was greater at 25°C whereas no differences were found in alluvial soil. Different moisture levels had diverse effects in the three soil types; in alluvial soil and in flysch the increased moisture resulted in greater values but in limestone these were slightly lower. These results can be used in developing non chemical control measures and designing efficient sampling techniques for the insect in the ground.  相似文献   
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Hydroponically grown wheat seedlings of two prominent Bulgarian cultivars (Katya and Prelom) were subjected to 48 h osmotic stress with PEG 8000 and were then rehydrated. The degree of stress was evaluated by monitoring relative water content, lipid peroxidation level, and accumulation of free proline and hydrogen peroxide in the leaves. Anatomy and ultrastructure of leaf tissue were observed under light microscopy. After imposition of stress, drought tolerant cultivar Katya displayed higher free proline content and significantly lower malondialdehyde and peroxide concentration in leaves than in the leaves of susceptible cultivar Prelom. After 24 h of rehydration Katya showed better ability to restore leaf water status and an apparent tendency towards recovery, whereas Prelom sustained higher levels of hydrogen peroxide, lipid peroxidation products and free proline and markedly low relative water content. Here, we have uncovered some of the characteristics displayed by cultivar Katya that enable it to survive and recover from severe osmotic stress. Interestingly, there was congruence between our results and the high level of cultivar Katya drought tolerance observed in the field.  相似文献   
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A novel human dual-specific protein phosphatase (DSP), designated DUSP27, is here described. The DUSP27 gene contains three exons, rather than the predicted 4-14 exons, and encodes a 220 amino acid protein. DUSP27 is structurally similar to other small DSPs, like VHR and DUSP13. The location of DUSP27 on chromosome 10q22, 50 kb upstream of DUSP13, suggests that these two genes arose by gene duplication. DUSP27 is an active enzyme, and its kinetic parameters and were determined. DUSP27 is a cytosolic enzyme, expressed in skeletal muscle, liver and adipose tissue, suggesting its possible role in energy metabolism.  相似文献   
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Cell therapy has been intensely studied for over a decade as a potential treatment for ischaemic heart disease. While initial trials using skeletal myoblasts, bone marrow cells and peripheral blood stem cells showed promise in improving cardiac function, benefits were found to be short‐lived likely related to limited survival and engraftment of the delivered cells. The discovery of putative cardiac ‘progenitor’ cells as well as the creation of induced pluripotent stem cells has led to the delivery of cells potentially capable of electromechanical integration into existing tissue. An alternative strategy involving either direct reprogramming of endogenous cardiac fibroblasts or stimulation of resident cardiomyocytes to regenerate new myocytes can potentially overcome the limitations of exogenous cell delivery. Complimentary approaches utilizing combination cell therapy and bioengineering techniques may be necessary to provide the proper milieu for clinically significant regeneration. Clinical trials employing bone marrow cells, mesenchymal stem cells and cardiac progenitor cells have demonstrated safety of catheter based cell delivery, with suggestion of limited improvement in ventricular function and reduction in infarct size. Ongoing trials are investigating potential benefits to outcome such as morbidity and mortality. These and future trials will clarify the optimal cell types and delivery conditions for therapeutic effect.  相似文献   
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Introduction

A subgroup of patients with primary Sjögren''s Syndrome (SS) and positive anticentromere antibodies (ACA) were recognized as having features intermediate between SS and systemic sclerosis (SSc). Our goal was to describe this group clinically and serologically and define its tendency to evolve to full blown SSc.

Methods

Among 535 patients with primary SS we identified 20 ACA positive (ACA+/SS). We compared them to 61 randomly selected ACA negative SS patients (ACA-/SS), 31 ACA positive SSc patients with sicca manifestations [SSc/(+) sicca] and 20 ACA positive SSc patients without sicca manifestations [SSc/(-) sicca].

Results

Prevalence of ACA among SS patients was 3.7%. Cases and controls did not differ in sex ratio and age at disease onset. ACA+/SS patients had a lower prevalence of dry eyes, hypergammaglobulinaemia, anti-Ro and anti-La antibodies and a higher prevalence of Raynaud''s phenomenon and dysphagia compared to ACA-/SS patients. They also had lower prevalence of telangiectasias, puffy fingers, sclerodactyly, Raynaud''s phenomenon, digital ulcers and gastroesophageal reflux in comparison to both of the SSc subgroups and a lower prevalence of dyspnoea and lung fibrosis compared to the SSc/(+) sicca subgroup. Two patients originally having ACA+/SS evolved to full blown SSc. Four deaths occurred, all among SSc patients. Kaplan Meier analysis showed a significant difference between cases and controls in time from disease onset to development of gastroesophageal reflux, telangiectasias, digital ulcers, arthritis, puffy fingers, xerostomia, hypergammaglobulinaemia and dysphagia.

Conclusions

ACA+/SS has a clinical phenotype intermediate between ACA-/SS and SSc and shows little tendency to evolve to SSc.  相似文献   
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Human sperm DNA damage may have adverse effects on reproductive outcome. Infertile men possess substantially more spermatozoa with damaged DNA compared to fertile donors. Although the extent of this abnormality is closely related to sperm function, the underlying etiology of ensuing male infertility is still largely controversial. Both intra-testicular and post-testicular events have been postulated and different mechanisms have been proposed to explain the presence of damaged DNA in human spermatozoa. Three among them, i.e. abnormal chromatin packaging, oxidative stress and apoptosis, are the most studied and discussed in the present review. Furthermore, results from numerous investigations are presented, including our own findings on these pathological conditions, as well as the techniques applied for their evaluation. The crucial points of each methodology on the successful detection of DNA damage and their validity on the appraisal of infertile patients are also discussed. Along with the conventional parameters examined in the standard semen analysis, evaluation of damaged sperm DNA seems to complement the investigation of factors affecting male fertility and may prove an efficient diagnostic tool in the prediction of pregnancy outcome.  相似文献   
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