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991.
The effect of sampling site and proximity of malignant tumor on the relative fatty acid composition of human breast adipose tissue was studied in 10 cases of breast cancer. The four anatomic quadrants of breast did not statistically significantly differ from each other in relation to any of the 30 fatty acids studied. Proximity of the malignant tumor did not affect the relative fatty acid composition of fat when compared with more distant sampling sites. Representative samples of breast adipose tissue for fatty acid composition analysis can be obtained from tissue adjacent to the tumor.  相似文献   
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The objective of this study was to assess the performance of the chemometric model to predict the proportion of the recrystallized polymorphs of nimodipine from the cosolvent formulations. Ranging from 100% to 0% (w/w) of polymorph I, the two polymorphs mixtures were prepared and characterized spectroscopically using Fourier transformed infrared spectroscopy (FTIR), near-infrared spectroscopy (NIR), and Raman spectroscopy. Instrumental responses were treated to construct multivariate calibration model using principal component regression (PCR) and partial least square regression approaches. Treated data showed better model fitting than without treatment, which demonstrated higher correlation coefficient (R2) and lower root mean square of standard error (RMSE) and standard error (SE). Multiple scattering correction and standard normal variate exhibited higher R2 and lower RMSE and SE values than second derivative. Goodness of fit for FTIR and NIR (R2 ~ 0.99) data was better than Raman (R2 ~ 0.95). Furthermore, the models were applied on the recrystallized polymorphs obtained by storing nimodipine-cosolvent formulations at selected stability conditions. The relative composition of the polymorphs differed with storage conditions. NIR-chemical imaging on recrystallized sample of nimodipine at 15°C qualitatively corroborated the model-based prediction of the two polymorphs. Therefore, these studies strongly suggest the importance of the potential utility of the chemometric model in predicting nimodipine polymorphs.  相似文献   
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The general microscopic characteristics of nerves are described in several textbooks of histology, but the specific microanatomies of most nerves that can be blocked by anesthesiologists are usually less well known. Our objective was to evaluate the 3D reconstruction of nerve fascicles from optical projection tomography images (OPT) and the ability to undertake an internal navigation exploring the morphology in detail, more specifically the fascicular interconnections. Median and lingual nerve samples were obtained from five euthanized piglets. OPT images of the samples were acquired and 3D reconstruction was performed. The OPT technique revealed the inner structure of the nerves at high resolution, including large and small fascicles, perineurium, interfascicular tissue, and epineurium. The fascicles were loosely packed inside the median nerve and more densely so in the lingual nerve. Analysis of the 3D models demonstrated that the nerve fascicles can show six general spatial patterns. Fascicular interconnections were clearly identified. The 3D reconstruction of nerve fascicles from OPT images opens a new path for research into the microstructure of the inner contents of fascicular nerve groups and their spatial disposition within the nerve including their interconnections. These techniques enable 3D images of partial areas of nerves to be produced and could became an excellent tool for obtaining data concerning the 3D microanatomy of nerves, essential for better interpretation of ultrasound images in clinical practice and thus avoiding possible neurological complications. Clin. Anat. 31:424–431, 2018. © 2017 Wiley Periodicals, Inc.  相似文献   
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Aim

The aim of our study was to describe right atrial (RA) and right ventricular (RV) function, assessed by Doppler tissue imaging and 2D speckle tracking echocardiography (2DSTE), in women with signs of early impaired left ventricular diastolic function (DD).

Methods and Results

In a cross‐sectional trial, standard parameters of diastolic and right heart function were investigated in 438 women of the Berlin Female Risk Evaluation (BEFRI) study. In a subset of women, average peak systolic RA strain (RAS), as well as the average peak systolic RV strain of the free wall (RVS free wall) and of all RV segments (average RV strain; RVS Avg), was analyzed using 2DSTE. Compared to women with normal diastolic function (DD0), RAS, RVS free wall and RVS Avg were significantly reduced in DD (43.1% ± 11.9%, ?26.7% ± 5.6%, and ?23.3% ± 3.5% in DD0; vs 35.1% ± 10.4%, ?23.9% ± 5.5%, and ?20.6% ± 3.8% in DD; P < .01). Peak RV myocardial velocity (RV‐IVV) and acceleration during isovolumetric contraction (RV‐IVA) were markedly higher in DD (15.0 ± 3.9 cm/s and 3.1 ± 1.0 m/s² in DD vs 11.9 ± 3.2 cm/s and 2.8 ± 0.8 m/s² in DD0; P < .05). RAS and RV‐IVV were significantly associated with DD after adjustment to age, BMI, and left atrial strain in multivariate regression analysis.

Conclusion

Systolic right heart function is significantly altered in DD. DTI as well as 2DSTE constitute sensitive echocardiographic tools that enable the diagnosis of impaired right heart mechanics in early‐staged DD.  相似文献   
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