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71.
A functional polymorphism in the promoter region of the human serotonin transporter gene (SLC6A4) has been associated with several dimensions of neuroticism and psychopathology, especially anxiety traits, but the predictive value of this genotype against these complex behaviors has been inconsistent. Serotonin [5- hydroxytryptamine, (5-HT)] function influences normal fear as well as pathological anxiety, behaviors critically dependent on the amygdala in animal models and in clinical studies. We now report that individuals with one or two copies of the short allele of the serotonin transporter (5-HTT) promoter polymorphism, which has been associated with reduced 5-HTT expression and function and increased fear and anxiety-related behaviors, exhibit greater amygdala neuronal activity, as assessed by BOLD functional magnetic resonance imaging, in response to fearful stimuli compared with individuals homozygous for the long allele. These results demonstrate genetically driven variation in the response of brain regions underlying human emotional behavior and suggest that differential excitability of the amygdala to emotional stimuli may contribute to the increased fear and anxiety typically associated with the short SLC6A4 allele.  相似文献   
72.
Cystic fibrosis is caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR). The most common mutation, DeltaF508, results in the production of a misfolded CFTR protein that is retained in the endoplasmic reticulum and targeted for degradation. Curcumin is a nontoxic Ca-adenosine triphosphatase pump inhibitor that can be administered to humans safely. Oral administration of curcumin to homozygous DeltaF508 CFTR mice in doses comparable, on a weight-per-weight basis, to those well tolerated by humans corrected these animals' characteristic nasal potential difference defect. These effects were not observed in mice homozygous for a complete knockout of the CFTR gene. Curcumin also induced the functional appearance of DeltaF508 CFTR protein in the plasma membranes of transfected baby hamster kidney cells. Thus, curcumin treatment may be able to correct defects associated with the homozygous expression of DeltaF508 CFTR.  相似文献   
73.
A 6.2‐year‐old 28‐kg (61.7 lb) intact female Golden Retriever was referred due to persistent and multiple cytopenias noted on a routine CBC prior to a mature ovariohysterectomy procedure. The patient's physical examination was unremarkable, and staging of the thorax and abdomen identified no abnormalities. At the referral hospital, moderate hypercalcemia, borderline anemia, and neutropenia were noted. Assessment of bone marrow samples by cytology, histology, immunohistochemistry, and flow cytometry indicated a T‐cell neoplasm. The patient was treated with a multi‐agent chemotherapy protocol for 6 months, which induced remission. Nine months after diagnosis, she relapsed with recurrence of hypercalcemia, cytopenias, and clinical illness. Single‐agent anthracycline (mitoxantrone) in combination with prednisone therapy was initiated for 3 months. Two months after completion, the patient relapsed again, and palliative therapy with prednisone was elected. The patient was euthanized 16 months after diagnosis due to progressive disease. Post‐mortem histopathologic evaluation showed extensive replacement of bone marrow by neoplastic cells, and infiltrates in multiple organs. The neoplasm was diagnosed as lymphoma rather than leukemia due to the lack of abnormal circulating cells throughout the course of disease. The neoplasm was detected only in marrow at the time of initial diagnosis, and the marrow was the most extensively effaced organ at the time of death. Therefore, leukemia or stage V lymphoma was considered unlikely. In patients with a cytopenia and lack of neoplastic leukocytosis or solid tissue masses, primary bone marrow lymphoma should be considered among the differential diagnoses.  相似文献   
74.
Journal of Pest Science - Biological control, or biocontrol, is the exploitation of living agents (incl. viruses) to combat pestilential organisms (incl. pathogens, pests, and weeds) for diverse...  相似文献   
75.
Journal of Pest Science - A correction to this paper has been published: https://doi.org/10.1007/s10340-021-01386-z  相似文献   
76.
We investigated the diversity of rhizobia isolated from different indigenous legumes in Flanders (Belgium). A total of 3810 bacterial strains were analysed originating from 43 plant species. Based on rep-PCR clustering, 16S rRNA gene and recA gene sequence analysis, these isolates belonged to Bradyrhizobium, Ensifer (Sinorhizobium), Mesorhizobium and Rhizobium. Of the genera encountered, Rhizobium was the most abundant (62%) and especially the species Rhizobiumleguminosarum, followed by Ensifer (19%), Bradyrhizobium (14%) and finally Mesorhizobium (5%). For two rep-clusters only low similarity values with other genera were found for both the 16S rRNA and recA genes, suggesting that these may represent a new genus with close relationship to Rhodopseudomonas and Bradyrhizobium. Primers for the symbiotic genes nodC and nifH were optimized and a phylogenetic sequence analysis revealed the presence of different symbiovars including genistearum, glycinearum, loti, meliloti, officinalis, trifolii and viciae. Moreover, three new nodC types were assigned to strains originating from Ononis, Robinia and Wisteria, respectively. Discriminant and MANOVA analysis confirmed the correlation of symbiosis genes with certain bacterial genera and less with the host plant. Multiple symbiovars can be present within the same host plant, suggesting the promiscuity of these plants. Moreover, the ecoregion did not contribute to the separation of the bacterial endosymbionts. Our results reveal a large diversity of rhizobia associated with indigenous legumes in Flanders. Most of the legumes harboured more than one rhizobial endosymbiont in their root nodules indicating the importance of including sufficient isolates per plant in diversity studies.  相似文献   
77.
78.
Shallow Radar soundings from the Mars Reconnaissance Orbiter reveal a buried deposit of carbon dioxide (CO(2)) ice within the south polar layered deposits of Mars with a volume of 9500 to 12,500 cubic kilometers, about 30 times that previously estimated for the south pole residual cap. The deposit occurs within a stratigraphic unit that is uniquely marked by collapse features and other evidence of interior CO(2) volatile release. If released into the atmosphere at times of high obliquity, the CO(2) reservoir would increase the atmospheric mass by up to 80%, leading to more frequent and intense dust storms and to more regions where liquid water could persist without boiling.  相似文献   
79.
ABSTRACT

This study examined if dwarf French bean (Phaseolus vulgaris L.) grown at northern latitudes develop seeds with superior yielding potential compared with plants grown at more southern latitudes. Two lines (BND3085 and BND3106) were grown at four sites across latitudes ranging from 52°N to 3°S. BND3085 and BND3106 seeds from Saskatoon grown plants (52°N) had the least damaged seed coats but the highest degree of electrolyte leakage from the seed and the lowest maximum germination rates. The Saskatoon (BND3085 and BND3106) and Nunhem (BND3106) seed lots had the lowest maximum germination rates when germinated at 28°C, 12°C, or when exposed to saline (100?mM NaCl) conditions. Saskatoon BND3085 seed produced plants with the lowest aboveground vegetative and total seed dry matter as well as the lowest pod number per plant. In contrast, plants grown from Saskatoon BND3106 seed produced 1.5-fold more total pods, 1.3-fold more total pods and 1.4-fold higher seed dry matter per plant as compared to plants grown from the Nunhem (51°N) or Arusha seed sources. This resulted in a 2.4–4.5% higher harvest index. These results suggest cultivar-specific dwarf French bean seed propagation at more northern sites may increase the productivity of the resulting crop.  相似文献   
80.
The aim of this study was to assess the effect of the Chilean rodeo exercise on some blood constituents, classically used to assess welfare, during rest; training with and without steer; and before and after official competitions. During the training season, 13 horses were assessed at their farms of origins, and samples were taken at rest and after training with and without a steer; then during the competition season, 16 horses were assessed at four different times, one before and three after the competition. The blood constituents assessed were packed cell volume (PCV), total proteins, fibrinogen, cortisol, neutrophil:lymphocyte ratio, creatine phosphokinase, aspartate transaminase, glutathione peroxidase, and serum amyloid A. Analysis of variance for repeated measures was applied using the Statistix 8.0 software, and a significance level of P < .05 was applied. For horses assessed during exercise with and without a steer, significant differences were observed for PCV, which were significantly lower at rest than after both exercises, and total proteins, which showed a significant increase only after exercise with steer. In the case of official competitions, PCV was significantly higher immediately after rodeo, and the lowest value for cortisol was observed the evening after competition (P < .05); among the enzymes assessed, creatine phosphokinase plasma concentrations immediately after rodeo and the evening after competition were significantly higher than concentrations the next morning. The use of physiological indicators did not seem to be sufficient to assess the overall effect of rodeo on the welfare of these horses, and other types of indicators should be considered in future studies.  相似文献   
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