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81.
Drying is one of the standard unit operations in the pharmaceutical industry and it is important to become aware of the circumstances
that dominate during the process. The purpose of this study was to test microcapsulated thermochromic pigments as heat indicators
in a fluid bed drying process. The indicator powders were manually granulated with α-lactose monohydrate resulting in three
particle-size groups. Also, pellets were coated with the indicator powders. The granules and pellets were fluidized in fluid
bed dryer to observe the progress of the heat flow in the material and to study the heat indicator properties of the indicator
materials. A tristimulus colorimeter was used to measure CIELAB color values. Color indicator for heat detection can be utilized
to test if the heat-sensitive API would go through physical changes during the pharmaceutical drying process. Both the prepared
granules and pellets can be used as heat indicator in fluid bed drying process. The colored heat indicators give an opportunity
to learn new aspects of the process at real time and could be exploded, for example, for scaling-up studies. 相似文献
82.
Kristina Laaksonen Liisa Helle Lauri Parkkonen Erika Kirveskari Jyrki P. M?kel? Satu Mustanoja Turgut Tatlisumak Markku Kaste Nina Forss 《PloS one》2013,8(4)
Amplitude or frequency alterations of spontaneous brain oscillations may reveal pathological phenomena in the brain or predict recovery from brain lesions, but the temporal evolution and the functional significance of these changes is not well known. We performed follow-up recordings of spontaneous brain oscillations with whole-head MEG in 16 patients with first-ever stroke in the middle cerebral artery territory, affecting upper limb motor function, 1–7 days (T0), 1 month (T1), and 3 months (T2) after stroke, with concomitant clinical examination. Clinical test results improved significantly from T0 to T1 or T2. During recovery (at T1 and T2), the strength of temporo–parietal ∼10-Hz oscillations in the affected hemisphere (AH) was increased as compared with the unaffected hemisphere. Abnormal low-frequency magnetic activity (ALFMA) at ∼1 Hz in the AH was detected in the perilesional cortex in seven patients at T0. In four of these, ALFMA persisted at T2. In patients with ALFMA, the lesion size was significantly larger than in the rest of the patients, and worse clinical outcome was observed in patients with persisting ALFMA. Our results indicate that temporo–parietal ∼10-Hz oscillations are enhanced in the AH during recovery from stroke. Moreover, stroke causes ALFMA, which seems to persist in patients with worse clinical outcome. 相似文献
83.
Most studies that have evaluated the association between anti-diabetic medication and cancer risk have suffered from methodological drawbacks. To avoid time-related biases, we evaluated the effect of treatment duration on the cancer risk among naive users of anti-diabetic medication as compared to non-users. In addition, we addressed the influence of common risk factors such as smoking and BMI. The study population comprised 23,394 participants of FINRISK surveys. Data on cancer and anti-diabetic medication were linked with the study cohorts. We applied Lexis tabulation to the data and analyzed split records by using Poisson regression. Changes in cancer incidence in relation to treatment duration were examined by modeling the rate ratio (RR). After a median follow-up of 9 years, 53 cancer cases among users of anti-diabetic medication and 1,028 among non-users were diagnosed. No significant difference in cancer risk between users and non-users was observed after adjustment. The RR for all medication regardless of its duration was 1.01 [95% CI 0.75–1.33], and 1.37 [0.94–1.94] for period of 1–4 years. The results were similar for metformin, sulfonylurea, and insulin. This study demonstrates that evaluation of the variation in cancer risk in relation to treatment duration is of particular importance for enhancing the accuracy of conclusions on the link between exposure to anti-diabetic medication and cancer risk. 相似文献
84.
85.
Introduced species, which establish in novel environments, provide an opportunity to explore trait evolution and how it may contribute to the distribution and spread of species. Here, we explore trait changes of the perennial herb Lupinus polyphyllus based on 11 native populations in the western USA and 17 introduced populations in Finland. More specifically, we investigated whether introduced populations outperformed native populations in traits measured in situ (seed mass) and under common garden conditions during their first year (plant size, flowering probability, and number of flowering shoots). We also explored whether climate of origin (temperature) influenced plant traits and quantified the degree to which trait variability was explained collectively by country and temperature as compared to other population‐level differences. Three out of four plant traits differed between the native and introduced populations; only seed mass was similar between countries, with most of its variation attributed to other sources of intraspecific variation not accounted for by country and temperature. Under common garden conditions, plants originating from introduced populations were larger than those originating from native populations. However, plants from the introduced range flowered less frequently and had fewer flowering shoots than their native‐range counterparts. Temperature of a population''s origin influenced plant size in the common garden, with plant size increasing with increasing mean annual temperature in both native and introduced populations. Our results of the first year reveal genetic basis for phenotypic differences in some fitness‐related traits between the native and introduced populations of L. polyphyllus. However, not all of these trait differences necessarily contribute to the invasion success of the species and thus may not be adaptive, which raises a question how persistent the trait differences observed in the first year are later in individuals’ life for perennial herbs. 相似文献
86.
87.
Alison M. Mondul Steven C. Moore Stephanie J. Weinstein Satu Männistö Joshua N. Sampson Demetrius Albanes 《Metabolomics : Official journal of the Metabolomic Society》2014,10(5):1036-1041
Although prostate cancer is the most commonly diagnosed cancer among men in developed populations, recent recommendations against routine prostate-specific antigen screening have cast doubt on its utility for early detection. We compared the metabolomic profiles of prospectively collected fasting serum from 74 prostate cancer cases and 74 controls selected from the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study cohort of male smokers. Circulating 1-stearoylglycerol (1-SG, or 1-monostearin) was statistically significantly inversely associated with risk of prostate cancer after Bonferroni correction for multiple comparisons (i.e., 420 identified metabolites) (OR 0.34, 95 % CI 0.20–0.58, p 6.3 × 10?5). The magnitude of this association did not differ by disease aggressiveness and was observed for cases diagnosed up to 23 years after blood collection. Similar but somewhat weaker prostate cancer risk signals were also evident for glycerol and alpha-ketoglutarate. In this population, men with higher serum 1-SG were less likely to develop prostate cancer, supporting a role for dysregulation of lipid metabolism in this malignancy. Additional studies are needed to retest the association and to examine 1-SG for its potential as a prostate cancer early detection marker. 相似文献
88.
Satu Mikkola Izabela Zagorowska Harri Lönnberg 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):1267-1268
Abstract The Zn2+ promoted hydrolysis of phosphodiester bonds of RNA has been studied by using a series of model compounds from dinucleoside monophosphates to oligo- and polynucleotides. The results will be discussed with respect to complex formation between the metal ion catalysts and substrates. 相似文献
89.
A major challenge in ecology is to understand how populations are affected by increased climate variability. Here, we assessed the effects of observed climate variability on different organismal groups (amphibians, insects, mammals, herbaceous plants and reptiles) by estimating the extent to which interannual variation in the annual population growth rates (CVλ) and the absolute value of the long-term population growth rate (|log λ|) were associated with short-term climate variability. We used empirical data (≥ 20 consecutive years of annual abundances) from 59 wild populations in the Northern Hemisphere, and quantified variabilities in population growth rates and climatic conditions (temperature and precipitation in active and inactive seasons) calculated over four- and eight-year sliding time windows. We observed a positive relationship between the variability of growth rate (CVλ) and the variability of temperature in the active season at the shorter timescale only. Moreover, |log λ| was positively associated with the variability of precipitation in the inactive season at both timescales. Otherwise, the direction of the relationships between population dynamics and climate variability (if any) depended largely on the season and organismal group in question. Both CVλ and |log λ| correlated negatively with species' lifespan, indicating general differences in population dynamics between short-lived and long-lived species that were not related to climate variability. Our results suggest that although temporal variation in population growth rates and the magnitude of long-term population growth rates are partially associated with short-term interannual climate variability, demographic responses to climate fluctuations might still be population-specific rather than specific to given organismal groups, and driven by other factors than the observed climate variability. 相似文献
90.
Do R Xie C Zhang X Männistö S Harald K Islam S Bailey SD Rangarajan S McQueen MJ Diaz R Lisheng L Wang X Silander K Peltonen L Yusuf S Salomaa V Engert JC Anand SS;INTERHEART investigators 《PLoS medicine》2011,8(10):e1001106