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11.
In B-cell chronic lymphocytic leukemia (B-CLL) the Rai and Binet staging criteria are not always able to accurately predict the prognosis of each patient. Rapidly evolving, violent disease is often seen in the so-called "good-prognosis" group, which highlights the need of additional and more refined prognostic markers. Several of these markers are described in the literature, with varying abilities to predict patient survival. Among the promising prognostic markers is flowcytometric analysis of CD38 on the monoclonal B cells in CLL. Several studies have shown that expression of CD38 is associated with a decreased overall-, or progression free survival. CD38 expression may be analyzed as percentage positive cells or as antibodies bound per cell. Addition of CD38 to the flow cytometry antibody panel for B-CLL analysis is a relatively easy way to obtain important prognostic information.  相似文献   
12.
13.
Three sulphur containing compounds, carbon disulphide, dimethyl disulphide and dimethyl sulphide were bioassayed for preference after admixing them in cereal base as ready bait block for use against commensal rat, R. rattus (wild type) in four way choice chamber system. Rat preference for different baits was also studied with automatic recording animal activity meter. Rats exhibited attractancy to the baits at 0.005% concentration of all the three compounds while at 0.01% concentration they have showed repellency. Dimethyl sulphide at 0.005% concentration showed better attractancy towards both sexes of rat.  相似文献   
14.
Road map to metastasis   总被引:9,自引:0,他引:9  
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15.
Approximately 0.5%-1% of the general population has been estimated to be heterozygous for a germline mutation in the ATM gene. Mutations in the ATM gene are responsible for the autosomal recessive disorder ataxia-telangiectasia (A-T) (MIM 208900). The finding that ATM-heterozygotes have an increased relative risk for breast cancer was supported by some studies but not confirmed by others. In view of this discrepancy, we examined the frequency of ATM germline mutations in a selected group of Dutch patients with breast cancer. We have analyzed ATM germline mutations in normal blood lymphocytes, using the protein-truncation test followed by genomic-sequence analysis. A high percentage of ATM germline mutations was demonstrated among patients with sporadic breast cancer. The 82 patients included in this study had developed breast cancer at age <45 and had survived >/=5 years (mean 15 years), and in 33 (40%) of the patients a contralateral breast tumor had been diagnosed. Among these patients we identified seven (8.5%) ATM germline mutations, of which five are distinct. One splice-site mutation (IVS10-6T-->G) was detected three times in our series. Four heterozygous carriers were patients with bilateral breast cancer. Our results indicate that the mutations identified in this study are "A-T disease-causing" mutations that might be associated with an increased risk of breast cancer in heterozygotes. We conclude that ATM heterozygotes have an approximately ninefold-increased risk of developing a type of breast cancer characterized by frequent bilateral occurrence, early age at onset, and long-term survival. The specific characteristics of our population of patients may explain why such a high frequency was not found in other series.  相似文献   
16.

Background

The objective of this study was to assess the effect of a web-based audit and feedback (A&F) intervention with outreach visits to support decision-making by multidisciplinary teams.

Methods

We performed a multicentre cluster-randomized trial within the field of comprehensive cardiac rehabilitation (CR) in the Netherlands. Our participants were multidisciplinary teams in Dutch CR centres who were enrolled in the study between July 2012 and December 2013 and received the intervention for at least 1 year. The intervention included web-based A&F with feedback on clinical performance, facilities for goal setting and action planning, and educational outreach visits. Teams were randomized either to receive feedback that was limited to psychosocial rehabilitation (study group A) or to physical rehabilitation (study group B). The main outcome measure was the difference in performance between study groups in 11 care processes and six patient outcomes, measured at patient level. Secondary outcomes included effects on guideline concordance for the four main CR therapies.

Results

Data from 18 centres (14,847 patients) were analysed, of which 12 centres (9353 patients) were assigned to group A and six (5494 patients) to group B. During the intervention, a total of 233 quality improvement goals was identified by participating teams, of which 49 (21%) were achieved during the study period. Except for a modest improvement in data completeness (4.5% improvement per year; 95% CI 0.65 to 8.36), we found no effect of our intervention on any of our primary or secondary outcome measures.

Conclusions

Within a multidisciplinary setting, our web-based A&F intervention engaged teams to define local performance improvement goals but failed to support them in actually completing the improvement actions that were needed to achieve those goals. Future research should focus on improving the actionability of feedback on clinical performance and on addressing the socio-technical perspective of the implementation process.

Trial registration

NTR3251
  相似文献   
17.
Both the development and relief of stress-related psychiatric conditions such as major depression (MD) and post-traumatic stress disorder (PTSD) have been linked to neuroplastic changes in the brain. One such change involves the birth of new neurons (neurogenesis), which occurs throughout adulthood within discrete areas of the mammalian brain, including the dorsal hippocampus (HIP). Stress can trigger MD and PTSD in humans, and there is considerable evidence that it can decrease HIP neurogenesis in laboratory animals. In contrast, antidepressant treatments increase HIP neurogenesis, and their efficacy is eliminated by ablation of this process. These findings have led to the working hypothesis that HIP neurogenesis serves as a biomarker of neuroplasticity and stress resistance. Here we report that local alterations in the expression of Sprouty2 (SPRY2), an intracellular inhibitor of growth factor function, produces profound effects on both HIP neurogenesis and behaviors that reflect sensitivity to stressors. Viral vector-mediated disruption of endogenous Sprouty2 function (via a dominant negative construct) within the dorsal HIP of adult rats stimulates neurogenesis and produces signs of stress resilience including enhanced extinction of conditioned fear. Conversely, viral vector-mediated elevation of SPRY2 expression intensifies the behavioral consequences of stress. Studies of these manipulations in HIP primary cultures indicate that SPRY2 negatively regulates fibroblast growth factor-2 (FGF2), which has been previously shown to produce antidepressant- and anxiolytic-like effects via actions in the HIP. Our findings strengthen the relationship between HIP plasticity and stress responsiveness, and identify a specific intracellular pathway that could be targeted to study and treat stress-related disorders.  相似文献   
18.
Single-molecule imaging of proteins in a 2D environment like membranes has been frequently used to extract diffusive properties of multiple fractions of receptors. In a 3D environment the apparent fractions however change with observation time due to the movements of molecules out of the depth-of-field of the microscope. Here we developed a mathematical framework that allowed us to correct for the change in fraction size due to the limited detection volume in 3D single-molecule imaging. We applied our findings on the mobility of activated glucocorticoid receptors in the cell nucleus, and found a freely diffusing fraction of 0.49±0.02. Our analysis further showed that interchange between this mobile fraction and an immobile fraction does not occur on time scales shorter than 150 ms.  相似文献   
19.
Streptococcus (S.) pneumoniae is the most common causative pathogen in community-acquired pneumonia. Nucleotide-binding oligomerization domain-containing (NOD) 2 is a pattern recognition receptor located in the cytosol of myeloid cells that is able to detect peptidoglycan fragments of S. pneumoniae. We here aimed to investigate the role of NOD2 in the host response during pneumococcal pneumonia. Phagocytosis of S. pneumoniae was studied in NOD2 deficient (Nod2 -/-) and wild-type (Wt) alveolar macrophages and neutrophils in vitro. In subsequent in vivo experiments Nod2 -/- and Wt mice were inoculated with serotype 2 S. pneumoniae (D39), an isogenic capsule locus deletion mutant (D39Δcps) or serotype 3 S. pneumoniae (6303) via the airways, and bacterial growth and dissemination and the lung inflammatory response were evaluated. Nod2 -/- alveolar macrophages and blood neutrophils displayed a reduced capacity to internalize pneumococci in vitro. During pneumonia caused by S. pneumoniae D39 Nod2 -/- mice were indistinguishable from Wt mice with regard to bacterial loads in lungs and distant organs, lung pathology and neutrophil recruitment. While Nod2 -/- and Wt mice also had similar bacterial loads after infection with the more virulent S. pneumoniae 6303 strain, Nod2 -/- mice displayed a reduced bacterial clearance of the normally avirulent unencapsulated D39Δcps strain. These results suggest that NOD2 does not contribute to host defense during pneumococcal pneumonia and that the pneumococcal capsule impairs recognition of S. pneumoniae by NOD2.  相似文献   
20.
Many mammalian herbivores show a temporal diet variation between graminoid-dominated and browse-dominated diets. We determined the causes of such a diet shift and its implications for conservation of a medium-sized ungulate—the bharal Pseudois nayaur. Past studies show that the bharal diet is dominated by graminoids (>80%) during summer, but the contribution of graminoids declines to about 50% in winter. We tested the predictions generated by two alternative hypotheses explaining the decline: low graminoid availability during winter causes bharal to include browse in their diet; bharal include browse, with relatively higher nutritional quality, in their diet to compensate for the poor quality of graminoids during winter. We measured winter graminoid availability in areas with no livestock grazing, areas with relatively moderate livestock grazing, and those with intense livestock grazing pressures. The chemical composition of plants contributing to the bharal diet was analysed. The bharal diet was quantified through signs of feeding on vegetation at feeding locations. Population structures of bharal populations were recorded using a total count method. Graminoid availability was highest in areas without livestock grazing, followed by areas with moderate and intense livestock grazing. The bharal diet was dominated by graminoids (73%) in areas with highest graminoid availability. Graminoid contribution to the bharal diet declined monotonically (50, 36%) with a decline in graminoid availability. Bharal young to female ratio was 3 times higher in areas with high graminoid availability than areas with low graminoid availability. The composition of the bharal winter diet was governed predominantly by the availability of graminoids in the rangelands. Our results suggest that bharal include more browse in their diet during winter due to competition from livestock for graminoids. Since livestock grazing reduces graminoid availability, creation of livestock-free areas is necessary for the conservation of grazing species such as the bharal and its predators including the endangered snow leopard in the Trans-Himalaya.  相似文献   
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