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21.
Our continued effort toward the development of the imidazo[1,2-a]pyrazine scaffold as Aurora kinase inhibitors is described. Bioisosteric approach was applied to optimize the 8-position of the core. Several new potent Aurora A/B dual inhibitors, such as 25k and 25l, were identified.  相似文献   
22.
Kerekes  J.  Tordon  R.  Nieuwburg  A.  Risk  L. 《Hydrobiologia》1994,(1):57-61
Aquatic bird population data in 40 oligotrophic lakes and ponds in Nova Scotia, Canada indicates that only lakes > 20 ha support territorial pairs of Common Loon (Gavia immer) and only lakes 40 ha produce their young. Broods of Common Merganser (Mergus merganser americanus) occurred in lakes > 25 ha and loon and merganser broods together occurred only in lakes 80 ha. The fish production in the lakes was estimated from the total phosphorus vs fish yield relationship obtained in similar, oligotrophic lakes in Ontario. Considering the fish consumption and mergansers until fledging along with the maintenance of the adults during the same period (about 200 and 130 kg fish respectively) and the estimated fish production in these lakes, there is a close balance between the size of water body and its fish production to the occupancy and production of piscivorous birds.  相似文献   
23.
Correct segregation of chromosomes is particularly challenging during the rapid nuclear divisions of early embryogenesis. This process is disrupted by HorkaD, a dominant-negative mutation in Drosophila melanogaster that causes female sterility due to chromosome tangling and nondisjunction during oogenesis and early embryogenesis. HorkaD also renders chromosomes unstable during spermatogenesis, which leads to the formation of diplo//haplo mosaics, including the gynandromorphs. Complete loss of gene function brings about maternal-effect lethality: embryos of the females without the HorkaD-identified gene perish due to disrupted centrosome function, defective spindle assembly, formation of chromatin bridges, and abnormal chromosome segregation during the cleavage divisions. These defects are indicators of mitotic catastrophe and suggest that the gene product acts during the meiotic and the cleavage divisions, an idea that is supported by the observation that germ-line chimeras exhibit excessive germ-line and cleavage function. The gene affected by the HorkaD mutation is lodestar, a member of the helicase-related genes. The HorkaD mutation results in replacement of Ala777 with Thr, which we suggest causes chromosome instability by increasing the affinity of Lodestar for chromatin.  相似文献   
24.

Introduction

We studied the effect of rosuvastatin on endothelial and macrovascular function, cardiovascular risk factors and the complement pathway in patients with systemic sclerosis (SSc).

Methods

Altogether 28 patients with SSc underwent laboratory and complex vascular assessments before and after six months of 20 mg rosuvastatin treatment. Flow-mediated dilation (FMD) of the brachial artery, as well as carotid artery intima-media thickness (ccIMT), carotid-femoral and aorto-femoral pulse wave-velocity (PWV) were analyzed by ECG-synchronized ultrasound. Ankle-brachial index (ABI) was determined by Doppler, and forearm skin microcirculation was assessed by Laser Doppler perfusion monitoring.

Results

Brachial artery FMD significantly improved upon rosuvastatin therapy (2.2% ± 3.3% before versus 5.7% ± 3.9% after treatment, P = 0.0002). With regard to patient subsets, FMD significantly improved in the 21 lcSSc patients (from 2.1% to 5.6%, P = 0.001). In the seven dcSSc patients, we observed a tendency of improvement in FMD (from 3% to 6%, P = 0.25). Changes in PWV, ccIMT and ABI were not significant. Mean triglyceride (1.7 ± 0.97 versus 1.3 ± 0.46 mmol/l, P = 0.0004), total cholesterol (5.3 ± 1.6 mmol/l versus 4.2 ± 1.3 mmol/l, P = 0.0003), low density lipoprotein cholesterol (3.0 ± 1.3 versus 2.2 ± 1.0 mmol/l, P = 0.005) and C-reactive protein levels (CRP) (5.1 ± 5.2 versus 3.4 ± 2.7, P = 0.01) levels significantly decreased after rosuvastatin treatment. Mean C3, C4 and IC levels also decreased significantly as compared to pretreatment values.

Conclusions

Six-month rosuvastatin therapy improves endothelial function and lowers CRP, C3, C4 and IC levels indicating possible favourable effects of this statin on the cardiovascular and immune system in SSc.  相似文献   
25.

Background

In this prospective study, mentally disordered perpetrators of severe violent and/or sexual crimes were followed through official registers for 59 (range 8 to 73) months. The relapse rate in criminality was assessed, compared between offenders sentenced to prison versus forensic psychiatric care, and the predictive ability of various risk factors (criminological, clinical, and of structured assessment instruments) was investigated.

Method

One hundred perpetrators were consecutively assessed between 1998 and 2001 by a clinical battery of established instruments covering DSM-IV diagnoses, psychosocial background factors, and structured assessment instruments (HCR-20, PCL-R, and life-time aggression (LHA)). Follow-up data was collected from official registers for: (i) recidivistic crimes, (ii) crimes during ongoing sanction.

Results

Twenty subjects relapsed in violent criminality during ongoing sanctions (n = 6) or after discharge/parole (n = 14). Individuals in forensic psychiatric care spent significantly more time at liberty after discharge compared to those in prison, but showed significantly fewer relapses. Criminological (age at first conviction), and clinical (conduct disorder and substance abuse/dependence) risk factors, as well as scores on structured assessment instruments, were moderately associated with violent recidivism. Logistic regression analyses showed that the predictive ability of criminological risk factors versus clinical risk factors combined with scores from assessment instruments was comparable, with each set of variables managing to correctly classify about 80% of all individuals, but the only predictors that remained significant in multiple models were criminological (age at first conviction, and a history of substance abuse among primary relatives).

Conclusions

Only one in five relapsed into serious criminality, with significantly more relapses among subjects sentenced to prison as compared to forensic psychiatric care. Criminological risk factors tended to be the best predictors of violent relapses, while few synergies were seen when the risk factors were combined. Overall, the predictive validity of common risk factors for violent criminality was rather weak.  相似文献   
26.
Activated T cells secrete Fas ligand (FasL)-containing vesicles (secreted vesicles) that induce death of target cells. We provide evidence that secreted vesicles from culture supernatants (Csup) of various origins are able to generate both Fas-dependent apoptotic and Fas-independent, nonapoptotic cell death. In the absence of Fas, the nonapoptotic, Fas-independent pathway could still induce cell death. In contrast to RIP-independent classical Fas-induced cell death triggered by cross-linked or membrane-bound FasL, CSup-derived stimuli-induced apoptosis exhibited unique molecular and enzymatic characteristics. It could be partially inhibited by blocking cathepsin D enzyme activity and required the presence of RIP. Whereas stimulation with CSup, derived from both FasL-overexpressing Jurkat cells and PBMC, could induce cell death, the requirements for Fas-associated death domain protein and caspase-9 were different between the two systems. Our study highlights an important distinction between cell contact-mediated and secreted vesicle-generated activation-induced cell death and also demonstrates that the type of the secreted vesicles can also modify the cell death route. We propose that besides cell-to-cell interaction-mediated Fas triggering, stimuli induced by secreted vesicles can mediate important additional cell death signals regulating activation-induced cell death under physiological conditions.  相似文献   
27.
28.
Annual planktonic primary production in five small oligotrophic lakes in Newfoundland, as measured at maximum depth (P-area) ranged from 5.6 to 12.0 g C/m2/year. Production per unit surface area representative of the whole lake basin (P-area ) was considerably lower in the shallower lakes (3.3 to 6.4 g C/m2/yr), while production expressed per unit volume representative of the whole lake basin (P-vol ) was the higher in the shallower lakes (0.6 to 4.1 g C/m3/yr). Production efficiency varied from lake to lake and throughout the year, but it remained fairly stable in a shorter term. Production efficiency and insolation was used to estimate annual production. Lakes with higher summer concentration of total phosphorus had higher rates of carbon assimilation.  相似文献   
29.
In the present study, the costly signaling theory (CST) is used to examine the effect of an offer of charity on social recognition. On behalf of a charitable organization, 186 students enrolled in 16 different courses were asked to offer support to unfamiliar persons in need. In accordance with our predictions, the results show that significantly more subjects are willing to give assistance if they make charity offers in the presence of their group members than when the offers are made in secret. In accordance with CST—but not with the prevailing explanations in social psychology—the likelihood of charity service was strongly influenced by the expected cost of altruistic behavior. Publicly demonstrated altruistic intentions yielded long-term benefits: Subjects who were willing to participate in a particular charity activity gained significantly higher sociometry scores (as a sign of social recognition) than did others. The cost of volunteerism correlated with social recognition in the case of a charity act judged as the most expensive (giving assistance to mentally retarded children), but not for the other categories of charity offer. Our results suggest that public generosity towards strangers as a costly signal may convey reliable information about subjects' personality traits, such as cooperativeness, but our data do not support the hypothesis that the signaling mechanism is related to sexual selection and mate choice.  相似文献   
30.

Objective

The aim of study was to analyze the accuracy of TRUS (transrectal ultrasound) vs. MRI (magnetic resonance imaging) and clinical gynecological examination estimation in the evaluation of tumor dimensions.

Methods

The patients inclusion criterion included primarily pathologically squamous cell carcinoma, but excluded were patients who had not undergone BT (brachytherapy) and treated with palliative intent. We offer two types of treatment for locally advanced cervical cancer: (a) radiochemotherapy followed by surgery and (b) exclusive radiochemotherapy. Imaging tests follow the presence of tumor and tumor size (width and thickness). Each examination was performed by a different physician who had no knowledge of the others’ findings. All patients underwent MRI prior to EBRT (external beam radiation therapy) while 18 of them also at the time of the first brachytherapy application. For the analysis we used the r-Pearson correlation coefficient.

Results

In 2013, 26 patients with cervical cancer were included. A total of 44 gynecological examinations were performed, 44 MRIs and 18 TRUSs. For the comparisons prior to EBRT the correlation coefficient between TRUS vs. MRI was r = 0.79 for AP and r = 0.83 for LL, for GYN vs. MRI was r = 0.6 for AP and r = 0.75 for LL. Prior to BT for GYN vs. MRI, r values were 0.60 and 0.63 for AP and LL, respectively; for GYN vs. TRUS, r values were 0.56 and 0.78 for AP and LL, respectively.

Conclusions

A high correlation between the three examinations was obtained. As such, TRUS can be considered a suitable method in the evaluation of tumor dimensions.  相似文献   
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