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71.
72.
A bioprocess for machine washable wool, combining the advantages of both protease and transglutaminase in a simultaneous enzymatic treatment has been developed. This process reduced the felting tendency of woven wool fabrics by 9% at the expense of only 2% weight and tensile strength loss. In contrast to previously described protease-based processes for shrink resistant wool, the anti-felting properties achieved in the simultaneous enzymatic treatment produced insignificant fibre damage, confirmed also by scanning electron images of the fabrics.  相似文献   
73.
The differential ability of various mu-opioid receptor (MOP) agonists to induce rapid receptor desensitization and endocytosis of MOP could arise simply from differences in their efficacy to activate G proteins or, alternatively, be due to differential capacity for activation of other signaling processes. We used AtT20 cells stably expressing a low density of FLAG-tagged MOP to compare the efficacies of a range of agonists to 1) activate G proteins using inhibition of calcium channel currents (ICa) as a reporter before and after inactivation of a fraction of receptors by beta-chlornaltrexamine, 2) produce rapid, homologous desensitization of ICa inhibition, and 3) internalize receptors. Relative efficacies determined for G protein coupling were [Tyr-D-Ala-Gly-MePhe-Glyol]enkephalin (DAMGO) (1) > or = methadone (0.98) > morphine (0.58) > pentazocine (0.15). The same rank order of efficacies for rapid desensitization of MOP was observed, but greater concentrations of agonist were required than for G protein activation. By contrast, relative efficacies for promoting endocytosis of MOP were DAMGO (1) > methadone (0.59) > morphine (0.07) > or = pentazocine (0.03). These results indicate that the efficacy of opioids to produce activation of G proteins and rapid desensitization is distinct from their capacity to internalize mu-opioid receptors but that, contrary to some previous reports, morphine can produce rapid, homologous desensitization of MOP.  相似文献   
74.
Autoimmune polyglandular syndrome type 1 (APS1), also known as autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED), is an autosomal recessive disorder characterized by the failure of several endocrine glands as well as nonendocrine organs. The autoimmune regulator (AIRE) gene responsible for APS1 on chromosome 21q22.3 has recently been identified. Here, we have characterized mutations in the AIRE gene by direct DNA sequencing in 16 unrelated APS1 families ascertained mainly from the USA. Our analyses identified four different mutations (a 13-bp deletion, a 2-bp insertion, one nonsense mutation, and one potential splice/donor site mutation) that are likely to be pathogenic. Fifty-six percent (9/16) of the patients contained at least one copy of a 13-bp deletion (1094–1106del) in exon 8 (seven homozygotes and two compound heterozygotes). A nonsense mutation (R257X) in exon 6 was also found in 31.3% (5/16) of the USA patients. These data are important for genetic diagnosis and counseling for families with autoimmune endocrine syndromes. Received: 24 August 1998 / Accepted: 29 September 1998  相似文献   
75.
The Smith-Lemli-Opitz syndrome (SLOS) is a multiple malformation/mental retardation syndrome caused by a deficiency of the enzyme 7-dehydrocholesterol Delta(7)-reductase. This enzyme converts 7-dehydrocholesterol (7-DHC) to cholesterol in the last step in cholesterol biosynthesis. The pathology of this condition may result from two different factors: the deficiency of cholesterol itself and/or the accumulation of precursor sterols such as 7-DHC. Although cholesterol synthesis is defective in cultured SLOS cells, to date there has been no evidence of decreased whole body cholesterol synthesis in SLOS and only incomplete information on the synthesis of 7-DHC and bile acids. In this first report of the sterol balance in SLOS, we measured the synthesis of cholesterol, other sterols, and bile acids in eight SLOS subjects and six normal children. The diets were very low in cholesterol content and precisely controlled. Cholesterol synthesis in SLOS subjects was significantly reduced when compared with control subjects (8.6 vs. 19.6 mg/kg per day, respectively, P < 0.002). Cholesterol precursors 7-DHC, 8-DHC, and 19-nor-cholestatrienol were synthesized in SLOS subjects (7-DHC synthesis was 1.66 +/- 1.15 mg/kg per day), but not in control subjects. Total sterol synthesis was also reduced in SLOS subjects (12 vs. 20 mg/kg per day, P < 0.022). Bile acid synthesis in SLOS subjects (3.5 mg/kg per day) did not differ significantly from control subjects (4.6 mg/kg per day) and was within the range reported previously in normals. Normal primary and secondary bile acids were identified.This study provides direct evidence that whole body cholesterol synthesis is reduced in patients with SLOS and that the synthesis of 7-DHC and other cholesterol precursors is profoundly increased. It is also the first reported measure of daily bile acid synthesis in SLOS and provides evidence that bile acid supplementation is not likely to be necessary for treatment. These sterol balance studies provide basic information about the biochemical defect in SLOS and strengthen the rationale for the use of dietary cholesterol in its treatment.  相似文献   
76.
Terrestrial vertebrate embryos face a risk of low oxygen availability (hypoxia) that is especially great during their transition to air‐breathing. To better understand how fetal brains respond to hypoxia, we examined the effects of low oxygen availability on brain activity in late‐stage chick embryos (day 18 out of a 21‐day incubation period). Using cFos protein expression as a marker for neuronal activity, we focused on two specific, immunohistochemically identified cell groups known to play an important role in regulating adult brain states (sleep and waking): the noradrenergic neurons of the Locus Coeruleus (NA‐LC), and the Hypocretin/Orexin (H/O) neurons of the hypothalamus. cFos expression was also examined in the Pallium (the avian analog of the cerebral cortex). In adult mammalian brains, cFos expression changes in a coordinated way in these areas. In chick embryos, oxygen deprivation simultaneously activated NA‐LC while deactivating H/O‐producing neurons; it also increased cFos expression in the Pallium. Activity in one pallial primary sensory area was significantly related to NA‐LC activity. These data reveal that at least some of the same neural systems involved in brain‐state control in adults may play a central role in orchestrating prenatal hypoxic responses, and that these circuits may show different patterns of coordination than seen in adults. © 2014 Wiley Periodicals, Inc. Develop Neurobiol 74: 1030–1037, 2014  相似文献   
77.
Hung CC  Carlson ET  Connor CE 《Neuron》2012,74(6):1099-1113
The basic, still unanswered question about visual object representation is this: what specific information is encoded by neural signals? Theorists have long predicted that neurons would encode medial axis or skeletal object shape, yet recent studies reveal instead neural coding of boundary or surface shape. Here, we addressed this theoretical/experimental disconnect, using adaptive shape sampling to demonstrate explicit coding of medial axis shape in high-level object cortex (macaque monkey inferotemporal cortex or IT). Our metric shape analyses revealed a coding continuum, along which most neurons represent a configuration of both medial axis and surface components. Thus, IT response functions embody a rich basis set for simultaneously representing skeletal and external shape of complex objects. This would be especially useful for representing biological shapes, which are often characterized by both complex, articulated skeletal structure and specific surface features.  相似文献   
78.
79.
Objectives To estimate the proportion of advertised non-consultant hospital posts that do not conform to nationally recognised terms and conditions of service and to investigate why these posts exist, who fills them, and what the doctors in such jobs do.Design Analysis of job advertisements and a cross sectional survey of advertisers.Setting Job advertisements in one of the leading UK publications listing hospital doctor vacancies (BMJ Careers).Results Nearly a quarter of non-consultant posts advertised in the two study periods (23% and 21%) were for non-standard grade posts. A questionnaire was sent to the medical staffing officer for each post. Of 430 questionnaires sent out 192 (45%) were returned. 98 trusts said they advertised non-standard grades because there was no more funding from the deanery for approved posts and 75 because service needs could not be met by doctors in training grades. In 132 posts (69%) the post holder would be required to do on-call work, and 50 advertisers (26%) required on-call duty for 1 in 5 or more frequently, which would conflict with the European Working Time Directive. 131 advertisers (68%) expected the posts to be filled by doctors from outside the European Economic Area.Conclusions Non-standard grade posts are mostly being created to meet service requirements when there is no more funding for standard training posts and are expected to be filled by doctors from overseas. Doctors in such posts can be more easily exploited and their careers hindered. The Department of Health''s annual census should include non-standard grade doctors.  相似文献   
80.
The study of wildlife activity patterns is an effective approach to understanding fundamental ecological and evolutionary processes. However, traditional statistical approaches used to conduct quantitative analysis have thus far had limited success in revealing underlying mechanisms driving activity patterns. Here, we combine wavelet analysis, a type of frequency‐based time‐series analysis, with high‐resolution activity data from accelerometers embedded in GPS collars to explore the effects of internal states (e.g., pregnancy) and external factors (e.g., seasonal dynamics of resources and weather) on activity patterns of the endangered giant panda (Ailuropoda melanoleuca). Giant pandas exhibited higher frequency cycles during the winter when resources (e.g., water and forage) were relatively poor, as well as during spring, which includes the giant panda's mating season. During the summer and autumn when resources were abundant, pandas exhibited a regular activity pattern with activity peaks every 24 hr. A pregnant individual showed distinct differences in her activity pattern from other giant pandas for several months following parturition. These results indicate that animals adjust activity cycles to adapt to seasonal variation of the resources and unique physiological periods. Wavelet coherency analysis also verified the synchronization of giant panda activity level with air temperature and solar radiation at the 24‐hr band. Our study also shows that wavelet analysis is an effective tool for analyzing high‐resolution activity pattern data and its relationship to internal and external states, an approach that has the potential to inform wildlife conservation and management across species.  相似文献   
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