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51.

Introduction  

It has been well documented that the pineal hormone, melatonin, which plays a major role in the control of reproduction in mammals, also plays a role in the incidence and growth of breast and mammary cancer. The curative effect of melatonin on the growth of dimethylbenz [a]anthracene-induced (DMBA-induced) mammary adenocarcinoma (ADK) has been previously well documented in the female Sprague-Dawley rat. However, the preventive effect of melatonin in limiting the frequency of cancer initiation has not been well documented.  相似文献   
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BACKGROUND: To review the outcome of subsequent pregnancies in conservatively managed cases of uterine rupture. METHODS: Charts of patients with full thickness uterine rupture in the past 25 years were reviewed and information on subsequent pregnancies was extracted from maternal and neonatal charts. RESULTS: Thirty-seven patients with uterine rupture were identified; the uterus was scarred in 62.2%. Ruptures were repaired in 26 (70.3%). Twelve patients subsequently conceived (24 pregnancies), with recurrence in 8/24 (33.3%) pregnancies or 5/12 (41.7%) patients. Patients with recurrence had a shorter median interval from previous rupture (2 versus 5 years), a higher incidence of previous longitudinal ruptures (60.0% versus 0.0%), and the median gestational age at the preceding rupture was lower without reaching statistical significance (34 versus 38 weeks; p = 0.209). CONCLUSIONS: Longitudinal ruptures and short intervals between rupture and subsequent pregnancy predispose to recurrence of uterine rupture.  相似文献   
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Journal of Neurology - Evidence of immune-mediated neurological syndromes associated with the severe acute respiratory syndrome coronavirus (SARS-CoV-2) infection is limited. We therefore...  相似文献   
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OBJECTIVE: The objective of our study was to illustrate the imaging findings of Budd-Chiari syndrome, including CT, MRI, sonographic, and angiographic findings. CONCLUSION: The key imaging findings in Budd-Chiari syndrome are occlusion of the hepatic veins, inferior vena cava, or both; caudate lobe enlargement; inhomogeneous liver enhancement; and the presence of intrahepatic collateral vessels and hypervascular nodules. Awareness of these findings is important for early diagnosis and appropriate treatment.  相似文献   
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Magnetic fields with quasi-symmetry are known to provide good confinement of charged particles and plasmas, but the extent to which quasi-symmetry can be achieved in practice has remained an open question. Recent work [M. Landreman and E. Paul, Phys. Rev. Lett. 128, 035001, 2022] reports the discovery of toroidal magnetic fields that are quasi-symmetric to orders-of-magnitude higher precision than previously known fields. We show that these fields can be accurately produced using electromagnetic coils of only moderate engineering complexity, that is, coils that have low curvature and that are sufficiently separated from each other. Our results demonstrate that these new quasi-symmetric fields are relevant for applications requiring the confinement of energetic charged particles for long time scales, such as nuclear fusion. The coils’ length plays an important role for how well the quasi-symmetric fields can be approximated. For the longest coil set considered and a mean field strength of 1 T, the departure from quasi-symmetry is of the order of Earth’s magnetic field. Additionally, we find that magnetic surfaces extend far outside the plasma boundary used by Landreman and Paul, providing confinement far from the core. Simulations confirm that the magnetic fields generated by the new coils confine particles with high kinetic energy substantially longer than previously known coil configurations. In particular, when scaled to a reactor, the best found configuration loses only 0.04% of energetic particles born at midradius when following guiding center trajectories for 200 ms.  相似文献   
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Commercial α-cellulose was compression-molded to produce 1A dog-bone specimens under various operating conditions without any additive. The resulting agromaterials exhibited a smooth, plastic-like surface, and constituted a suitable target as replacement for plastic materials. Tensile and three-points bending tests were conducted according to ISO standards related to the evaluation of plastic materials. The specimens had strengths comparable to classical petroleum-based thermoplastics. They also exhibited high moduli, which is characteristic of brittle materials. A higher temperature and higher pressure rate produced specimens with higher mechanical properties while low moisture content produced weaker specimens. Generally, the strong specimen had higher specific gravity and lower moisture content. However, some parameters did not follow the general trend e.g., thinner specimen showed much higher Young’s Modulus, although their specific gravity and moisture content remained similar to control, revealing a marked skin-effect which was confirmed by SEM observations.  相似文献   
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