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991.
Eric C. Ip 《Bioethics》2019,33(8):931-936
This article will explore whether the law should allow people with anorexia nervosa to refuse nutrition and hydration with special reference to the English decision in Re E (Medical Treatment: Anorexia). It argues that the judge in that case made the correct decision in holding that the patient, who suffered from severe anorexia nervosa, lacked capacity to make valid advance directives under the Mental Capacity Act 2005 of the United Kingdom, and that medical procedures that are apparently against her wishes should be carried out for the sake of preserving her life. The law should generally not permit patients with anorexia nervosa to decline nutrition and hydration, precisely because their autonomous ability to make such decisions has been substantially circumscribed by this psychiatric condition.  相似文献   
992.
The neurohypophysial hormone arginine vasopressin (AVP) plays important roles in fluid regulation and vascular resistance. Differences in AVP receptor expression, particularly mediated through variation in the noncoding promoter region of the primary receptor for AVP (AVPR1a), may play a role in social phenotypes, particularly social monogamy, in rodents and humans. Among primates, social monogamy is rare, but is common among New World monkeys (NWM). AVP is a nonapeptide and generally conserved among eutherian mammals, although a recent paper demonstrated that some NWM species possess a novel form of the related neuropeptide hormone, oxytocin. We therefore characterized variation in the AVP and AVPR1a genes in 22 species representing every genus in the three major platyrrhine families (Cebidae, Atelidae and Pitheciidae). For AVP, a total of 16 synonymous substitutions were detected in 15 NWM species. No non-synonymous substitutions were noted, hence, AVP is conserved in NWM. By contrast, relative to the human AVPR1a, 66 predicted amino acids (AA) substitutions were identified in NWM. The AVPR1a N-terminus (ligand binding domain), third intracellular (G-protein binding domain), and C-terminus were variable among species. Complex evolution of AVPR1a is also apparent in NWM. A molecular phylogenetic tree inferred from AVPR1a coding sequences revealed some consensus taxonomic separation by families, but also a mixed group composed of genera from all three families. The overall dN/dS ratio of AVPR1a was 0.11, but signals of positive selection in distinct AVPR1a regions were observed, including the N-terminus, in which we identified six potential positive selection sites. AA substitutions at positions 241, 319, 399 and 409 occurred uniquely in marmosets and tamarins. Our results enhance the appreciation of genetic diversity in the mammalian AVP/AVPR1a system, and set the stage for molecular modeling of the neurohypophyseal hormones and social behavior in primates.  相似文献   
993.
This paper extends the multilevel survival model by allowing the existence of cured fraction in the model. Random effects induced by the multilevel clustering structure are specified in the linear predictors in both hazard function and cured probability parts. Adopting the generalized linear mixed model (GLMM) approach to formulate the problem, parameter estimation is achieved by maximizing a best linear unbiased prediction (BLUP) type log‐likelihood at the initial step of estimation, and is then extended to obtain residual maximum likelihood (REML) estimators of the variance component. The proposed multilevel mixture cure model is applied to analyze the (i) child survival study data with multilevel clustering and (ii) chronic granulomatous disease (CGD) data on recurrent infections as illustrations. A simulation study is carried out to evaluate the performance of the REML estimators and assess the accuracy of the standard error estimates.  相似文献   
994.
Articular cartilage is a heterogeneous tissue, with cell density and organization varying with depth from the surface. The objectives of the present study were to establish a method for localizing individual cells in three-dimensional (3D) images of cartilage and quantifying depth-associated variation in cellularity and cell organization at different stages of growth. Accuracy of nucleus localization was high, with 99% sensitivity relative to manual localization. Cellularity (million cells per cm3) decreased from 290, 310, and 150 near the articular surface in fetal, calf, and adult samples, respectively, to 120, 110, and 50 at a depth of 1.0 mm. The distance/angle to the nearest neighboring cell was 7.9 microm/31 degrees , 7.1 microm/31 degrees , and 9.1 microm/31 degrees for cells at the articular surface of fetal, calf, and adult samples, respectively, and increased/decreased to 11.6 microm/31 degrees , 12.0 microm/30 degrees , and 19.2 microm/25 degrees at a depth of 0.7 mm. The methodologies described here may be useful for analyzing the 3D cellular organization of cartilage during growth, maturation, aging, degeneration, and regeneration.  相似文献   
995.
Before its worldwide famous awakening in 1991, Mt Pinatubo volcano erupted between 800 and 500 year BP. The impacts of this little known eruption are progressively coming to light with the discovery of archaeological sites and the study of oral and geographical records. Recent archaeological excavations have shown that pyroclastic flows and lahar onslaughts have probably led to the abandonment of major settlements on both sides of Mt. Pinatubo. The location of these archaeological sites and the toponyms on the east flanks of the volcano suggest a general redistribution of the population downstream toward lands reclaimed on the sea due to heavy lahar material deposition. These population movements did not occur on the west side of the mountain despite similar land reclamation. Such topographic and socio-demographic changes have deeply disturbed the economic environment since it is hypothesized that extensive trade with China and other foreign “countries” profited from the easy penetration of commercial vessels into the bays that would have been filled up by lahar deposits. Finally oral memory records, such as legends and epics, help define the ethnic groups that have suffered from the eruption (e.g. Aetas, Kapampangans and Sambals). Understanding what happened 500 years ago turns very useful to anticipate the consequences of future events.  相似文献   
996.
We implemented both structure-based drug design and the concept of polyvalency to discover a series of potent and unsymmetrical Schistosoma japonicum glutathione S-transferase (SjGST) inhibitors 10-12. This strategy achieved not only an excellent enhancement (10- to 490-fold) in the inhibitory potency, compared to the monofunctional analogues 1-5, but was also an effective modification by selecting a hydrophobic moiety with a flexible linker. The designed compounds with a low micromolar hit demonstrate special values in refining the new generation of SjGST inhibitors. The stoichiometry of the binding is one inhibitor molecule per SjGST monomer via isothermal titration calorimetric measurement.  相似文献   
997.
998.
To assess the in vivo influence of the systemic immune system upon microglia, six defined brain regions of adult SCID mice (n = 10) lacking functional T- and B-lymphocytes have been analyzed by NDPase histochemistry, morphometry and immunohistochemistry. Despite absence of neuropathology and lack of microglial activation, microglial numerical density was significantly increased in SCID mice. Elevation was most marked in the cerebellar granular layer (by 32.6%; 95% confidence interval: 9.9-58.7%), followed by the fimbria hippocampi and the molecular layer of hippocampal CA1/CA3 region. These data need to be taken into account when using SCID mice as a model for microglial reaction in immunodeficient mice.  相似文献   
999.
Protein kinase C (PKC) is involved in signaling that modulates the proliferation and differentiation of many cell types, including mammary epithelial cells. In addition, changes in PKC expression or activity have been observed during mammary carcinogenesis. In order to examine the involvement of specific PKC isoforms during normal mammary gland development, the expression and localization of PKCs alpha, delta, epsilon and zeta were examined during puberty, pregnancy, lactation, and involution. By immunoblot analysis, expression of PKC alpha, delta, epsilon and zeta proteins was increased in mammary epithelial organoids during the transition from puberty to pregnancy. In mammary gland frozen sections, PKCs alpha, delta, epsilon and zeta were stained in the luminal epithelium and myoepithelium, in varying isoform-and developmental stage-specific locations. PKC alpha was found in a punctate apical localization in the luminal epithelium during pregnancy. During lactation, PKC epsilon was present in the nucleus, and PKC zeta was concentrated in the subapical region of the luminal epithelium. Additionally, marked staining for PKCs alpha, delta, epsilon, and zeta was observed in the myoepithelial cells at the base of ducts and alveoli. This basal ductal and alveolar staining differed in intensity in a developmentally-specific fashion. During most time points (virgin, pregnant, lactating, and early involution), myoepithelial cells of the duct were more intensely stained than those lining the alveoli for PKCs alpha, delta, epsilon and zeta. During late involution (days 9-12), the preferential staining of ducts was lost or reversed, and the myoepithelial cells lining the regressing alveolar structures stained equally (PKCs epsilon and zeta) or more intensely (PKCs alpha and delta), coincident with the thickening of the myoepithelial cells surrounding the regressing alveoli. The increased PKC isoform staining at the base of alveoli during involution suggests that alveolar regression may be influenced by alterations in signaling in the alveolar myoepithelium.  相似文献   
1000.
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