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431.
Biological Cybernetics - 相似文献
432.
433.
Claus B. Jørgensen Anne Katrine Winterø Martine Yerle Merete Fredholm 《Mammalian genome》1997,8(6):423-427
Complementary DNA sequences were selected from a resource of tentatively identified clones from a porcine small intestine
cDNA library. Forty PCR primer pairs were designed to amplify 101–309 base pairs of the 3′ untranslated region of the genes.
The PCR conditions were optimized by altering both formamide and magnesium concentrations on samples of pig, mouse, and hamster
DNA. Twenty primer pairs that, under stringent conditions, were pig-specific and amplified the expected fragments were chosen
for regional assignment in a pig/rodent hybrid cell panel. Furthermore, 22 primer pairs were chosen to amplify DNA from the
parental animals of the PiGMaP shared reference families in order to detect possible polymorphisms. Primer pairs that generated
polymorphisms were used for genetic mapping. A total of 22 porcine expressed sequence tags (ESTs) were cytogenetically or
genetically mapped by this approach. Twelve of the mapped ESTs could be added to the human–porcine comparative map.
Received: 8 December 1996 / Accepted: 31 January 1997 相似文献
434.
Marie Starzer Helene Gjervig Hansen Carsten Hjorthøj Nikolai Albert Merete Nordentoft Trine Madsen 《World psychiatry》2023,22(3):424-432
This study aimed to identify the 20-year trajectories of positive and negative symptoms after the first psychotic episode in a sample of patients with an ICD-10 diagnosis of schizophrenia spectrum disorder, and to investigate the baseline characteristics and long-term outcomes associated with these trajectories. A total of 373 participants in the OPUS trial were included in the study. Symptoms were assessed at baseline and after 1, 2, 5, 10 and 20 years using the Scales for the Assessment of Positive and Negative Symptoms. We used latent class growth mixture modelling to identify trajectories, and multinominal regression analyses to investigate predictors of membership to identified trajectories. Five trajectories of positive symptoms were identified: early continuous remission (50.9% of the sample), stable improvement (18.0%), intermittent symptoms (10.2%), relapse with moderate symptoms (11.9%), and continuous severe symptoms (9.1%). Substance use disorder (odds ratio, OR: 2.83, 95% CI: 1.09-7.38, p=0.033), longer duration of untreated psychosis (OR: 1.02, 95% CI: 1.00-1.03, p=0.007) and higher level of negative symptoms (OR: 1.60, 95% CI: 1.07-2.39, p=0.021) were predictors of the relapse with moderate symptoms trajectory, while only longer duration of untreated psychosis (OR: 1.01, 95% CI: 1.00-1.02, p=0.030) predicted membership to the continuous severe symptoms trajectory. Two trajectories of negative symptoms were identified: symptom remission (51.0%) and continuous symptoms (49.0%). Predictors of the continuous symptoms trajectory were male sex (OR: 3.03, 95% CI: 1.48-6.02, p=0.002) and longer duration of untreated psychosis (OR: 1.01, 95% CI: 1.00-1.02, p=0.034). Trajectories displaying continuous positive and negative symptoms were linked to lower neurocognition, as measured by the Brief Assessment of Cognition in Schizophrenia (BACS) (z-score: –0.78, CI: –1.39 to –0.17, for continuous positive symptoms; z-score: –0.33, CI: –0.53 to –0.13, for continuous negative symptoms). The same trajectories were also linked to higher use of antipsychotic medication at 20-year follow-up (continuous positive symptoms: 78%; continuous negative symptoms: 67%). These findings suggest that the majority of patients with first-episode schizophrenia spectrum disorder have a trajectory with early stable remission of positive symptoms. Long duration of untreated psychosis and comorbid substance abuse are modifiable predictors of poor trajectories for positive symptoms in these patients. In about half of patients, negative symptoms do not improve over time. These symptoms, in addition to being associated with poor social and neurocognitive functioning, may prevent patients from seeking help. 相似文献
435.
Influence of early life characteristics on psychiatric admissions and impact of psychiatric disease on inflammatory biomarkers and survival: a Danish cohort study
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437.
Niels Møller Israelsen Mette Mogensen Mikkel Jensen Merete Haedersdal Ole Bang 《Journal of biophotonics》2021,14(11):e202100083
Bedside diagnosis of skin cancer remains a challenging task. The real-time noninvasive technology of optical coherence tomography (OCT) masters a high diagnostic accuracy in basal cell carcinoma (BCC) but a lower specificity in recognizing imitators and other carcinomas. We investigate the delicate signal of papillary dermis using an in-house developed ultrahigh resolution OCT (UHR-OCT) system with shadow compensation and a commercial multi-focus high resolution OCT (HR-OCT) system for clinical BCC imaging. We find that the HR-OCT system struggled to resolve the dark band signal of papillary dermis where the UHR-OCT located this in all cases and detected changes in signal width. UHR-OCT is able to monitor extension and position of papillary dermis suggesting a novel feature for delineating superficial BCCs in pursuit of a fast accurate diagnosis. Comprehensive studies involving more patients are imperative in order to corroborate results. 相似文献
438.
Intercalibration of assessment methods for macrophytes in lowland streams: direct comparison and analysis of common metrics 总被引:3,自引:3,他引:0
The results of four macrophyte assessment methods (French Indice Biologique Macrophytique en Rivière, German Reference Index,
British Mean Trophic Rank and Dutch Macrophyte Score) were compared, based on plant survey data of medium-sized lowland streams
in Central Europe. To intercalibrate the good quality class boundaries two alternative methods were applied: direct comparison
and the use of “common metrics”. While the French and British methods were highly related (R2>0.75), the German RI showed less (0.20<R2<0.55) and the Dutch DMS least correlation (R2<0.10) with other methods. Of 70 macrophyte metrics tested only Ellenberg_N was considerably related to three of the national
assessment methods, thus representing a potential common metric for intercalibration. Comparison of quality class boundaries
via regression analysis using both intercalibration approaches revealed major differences between classifications of the French,
German and British methods, which are, in addition, related in a nonlinear way. 相似文献
439.
440.
John R. Birk 《Biological cybernetics》1972,10(4):201-203
A model is formulated for the conversion of a motoneuron's spike train to tension in a muscle. This model demonstrates that
a spike train whose adjacent interspike intervals are negatively correlated results in a steady-state tension which fluctuates
less about its mean value than if the interspike intervals are randomly arranged. The ability of a spike train to develop
more distinguishable levels of tension by negative correlation between adjacent interspike intervals is more significant for
interspike interval distributions with greater dispersion. The number of distinguishable tension levels increases by about
33 percent when a typical set of neuromuscular parameters are used. These results may be generalized to the smoothing of postsynaptic
potentials and the regulation of blood pressure. 相似文献