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11.
Physician perception of medication adherence may alter prescribing patterns. Perception of patients has been linked to readily observable factors, such as race and age. Obesity shares a similar stigma to these factors in society. We hypothesized that physicians would perceive patients with a higher BMI as nonadherent to medication. Data were collected from the baseline visit of a randomized clinical trial of patient–physician communication (240 patients and 40 physicians). Physician perception of patient medication adherence was measured on a Likert scale and dichotomized as fully adherent or not fully adherent. BMI was the predictor of interest. We performed Poisson regression analyses with robust variance estimates, adjusting for clustering of patients within physicians, to examine the association between BMI and physician perception of medication adherence. The mean (s.d.) BMI was 32.6 (7.7) kg/m2. Forty‐five percent of patients were perceived as nonadherent to medications by their physicians. Higher BMI was significantly and negatively associated with being perceived as adherent to medication (prevalence ratio (PrR) 0.76, 95% confidence interval (CI): 0.64–0.90; P = 0.002; per 10 kg/m2 increase in BMI). BMI remained significantly and negatively associated with physician perception of medication adherence after adjustment for patient and physician characteristics (PrR 0.80, 95% CI: 0.66–0.96; P = 0.020). In this study, patients with higher BMI were less likely to be perceived as adherent to medications by their providers. Physician perception of medication adherence has been shown to affect prescribing patterns in other studies. More work is needed to understand how this perception may affect the care of patients with obesity.  相似文献   
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The eight class I, set 1 super-suppressor genes, SUP2, SUP3, SUP4, SUP5, SUP6, SUP7, SUP8 and SUP11 are not closely linked and map at distinct loci throughout the genome of yeast. Each of these suppressors causes the production of 5 to 10% of the normal amount of iso-1-cytochrome c when it is individually coupled to the ochre (UAA) mutant cy1-2. All eight iso-1-cytochromes c contain a residue of tyrosine at position 20 which corresponds to the site of the ochre codon. Several of these super-suppressors also were shown to act on cy1-9, but at a much lower efficiency. It was shown that iso-1-cytochrome c from one of the suppressed cy1-9 strains contains a tyrosine at position 2, which corresponds to the site of the ochre codon in this mutant. It is suggested that the gene product of the eight super-suppressors is tyrosine transfer RNA.  相似文献   
14.
Neodryinus typhlocybae (Hymenoptera: Dryinidae) is a natural enemy of the planthopper Metcalfa pruinosa, which was introduced from North America into Europe and has become established in various regions as a pest species. Vibrational signals play a crucial role in the communication of M. pruinosa, which appears to be exploited by N. typhlocybae. Scanning and transmission electron microscopy have shown that the antennae of N. typhlocybae females have peculiar and complex sensory structures: deep longitudinal grooves that house long sensilla trichodea, termed here “Antennal Dorsal Organs.” Such structures were not present on male antennae. These sensilla extend for the length of the grooves, without contact with the groove cuticle. Their hair shaft is empty and aporous, and inserted into a specialized socket, underneath which there is a cuticular ampulla‐like chamber. Each sensillum is associated with two sensory neurons: one terminates at the proximal end of the dendritic sheath; the other continues into the sensillum sinus and is enclosed in the dendritic sheath. This second sensory neuron then enters the ampulla‐like chamber through the circular opening, and then terminates with a conspicuous tubular body at the shaft base. The possible involvement of this peculiar structure in the context of host recognition mechanism is discussed. J. Morphol. 277:128–137, 2016. © 2015 Wiley Periodicals, Inc.  相似文献   
15.
We interact with the world through the assessment of available, but sometimes imperfect, sensory information. However, little is known about how variance in the quality of sensory information affects the regulation of controlled actions. In a series of three experiments, comprising a total of seven behavioral studies, we examined how different types of spatial frequency information affect underlying processes of response inhibition and selection. Participants underwent a stop-signal task, a two choice speed/accuracy balance experiment, and a variant of both these tasks where prior information was given about the nature of stimuli. In all experiments, stimuli were either intact, or contained only high-, or low- spatial frequencies. Overall, drift diffusion model analysis showed a decreased rate of information processing when spatial frequencies were removed, whereas the criterion for information accumulation was lowered. When spatial frequency information was intact, the cost of response inhibition increased (longer SSRT), while a correct response was produced faster (shorter reaction times) and with more certainty (decreased errors). When we manipulated the motivation to respond with a deadline (i.e., be fast or accurate), removal of spatial frequency information slowed response times only when instructions emphasized accuracy. However, the slowing of response times did not improve error rates, when compared to fast instruction trials. These behavioral studies suggest that the removal of spatial frequency information differentially affects the speed of response initiation, inhibition, and the efficiency to balance fast or accurate responses. More generally, the present results indicate a task-independent influence of basic sensory information on strategic adjustments in action control.  相似文献   
16.
Morphological studies were carried out with peach flower buds collected monthly in 1989 and 1990, from two months before leaf fall (7 March) until two to three weeks before bloom (7/8 August). Chilled (2–4°C for 30 days) and unchilled buds were exposed to 20 to 25°C, 100% RH and continuous light. Gibberellin A3 (3 ng or 30 ng) was applied to some of the non-chilled cuttings at three days intervals. Then, 12, 19, and 26 days after they were planted, the buds were sampled and processed for histological studies. Cultured flower buds (chilled or unchilled) had accelerated anther and gynoecium morphogenesis after 12 days under controlled conditions, compared to buds processed immediately after collection from the field. Chilling treatment augmented the bud culture effect, while Gibberellin A3 applications to the excised buds retarded bud morphogenesis to a stage comparable to that of buds collected directly from the field. This, suggests that the comparatively high levels of Gibberellin A1/3 we previously found in mid winter [15, 18] could be at least one of the factors that controls floral bud dormancy by retarding anther and gynoecium development.  相似文献   
17.
Aim The seagrass, Posidonia oceanica is a clonal angiosperm endemic to the Mediterranean Sea. Previous studies have suggested that clonal growth is far greater than sexual recruitment and thus leads to low clonal diversity within meadows. However, recently developed microsatellite markers indicate that there are many different genotypes, and therefore many distinct clones present. The low resolution of markers used in the past limited our ability to estimate clonality and assess the individual level. New high‐resolution dinucleotide microsatellites now allow genetically distinct individuals to be identified, enabling more reliable estimation of population genetic parameters across the Mediterranean Basin. We investigated the biogeography and dispersal of P. oceanica at various spatial scales in order to assess the influence of different evolutionary factors shaping the distribution of genetic diversity in this species. Location The Mediterranean. Methods We used seven hypervariable microsatellite markers, in addition to the five previously existing markers, to describe the spatial distribution of genetic variability in 34 meadows spread throughout the Mediterranean, on the basis of an average of 35.6 (± 6.3) ramets sampled. Results At the scale of the Mediterranean Sea as a whole, a strong east–west cleavage was detected (amova) . These results are in line with those obtained using previous markers. The new results showed the presence of a putative secondary contact zone at the Siculo‐Tunisian Strait, which exhibited high allelic richness and shared alleles absent from the eastern and western basins. F statistics (pairwise θ ranges between 0.09 and 0.71) revealed high genetic structure between meadows, both at a small scale (about 2 to 200 km) and at a medium scale within the eastern and western basins, independent of geographical distance. At the intrameadow scale, significant spatial autocorrelation in six out of 15 locations revealed that dispersal can be restricted to the scale of a few metres. Main conclusions A stochastic pattern of effective migration due to low population size, turnover and seed survival is the most likely explanation for this pattern of highly restricted gene flow, despite the importance of an a priori seed dispersal potential. The east–west cleavage probably represents the outline of vicariance caused by the last Pleistocene ice age and maintained to this day by low gene flow. These results emphasize the diversity of evolutionary processes shaping the genetic structure at different spatial scales.  相似文献   
18.
Monoclonal antibodies reacting with the A59 strain of mouse hepatitis virus (MHV-A59) were characterized and those specific to the E2 major envelope glycoprotein were studied in detail. Antibodies were tested for their ability to neutralize viral infectivity (N+ characteristic) and prevent viral-induced cell-to-cell fusion (F+ characteristic). All four possible combinations of activities reflecting E2 functions were found, i.e., N+F+, N-F-, N+F-, and N-F+. In addition, competitive binding studies with these monoclonal antibodies revealed two nonoverlapping antigenic regions. The first region, designated A, was recognized by antibodies which included each of the four functional types. Region B was identified by a single monoclonal antibody with N-F- activities. The existence of antibodies which only neutralize virus or only block viral-induced fusion implies that the structures on E2 which serve as targets for neutralization and which induce fusion are not identical. The critical determinants for neutralization and fusion must be closely related topographically on E2 since both N+F- and N-F+ antibodies recognize the same antigenic region.  相似文献   
19.
Summary The massa caudalis of the subcommissural organ-Reissner's fiber complex of lamprey larvae (Geotria australis) was studied immunocytochemically at the ultrastructural level by use of the immunoperoxidase-silver methenamine procedure. An antiserum raised against bovine Reissner's fiber was utilized as primary antibody.The caudalmost portion of the central canal and its ampulla caudalis communicate, via wide intercellular spaces in their dorsal wall, with large cavities or lacunae. In addition, distinct openings in the dorsal wall of the ampulla establish an open communication between the latter and the lacunae. The lacunae are lined by slender processes of cells of unknown nature. No junctional complexes can be observed between these cells, which lack a basal lamina. The lacunae communicate with structures resembling blood capillaries, however, they are devoid of a basal lamina. These peculiar vessels, in turn, are in direct communication with characteristic blood capillaries.Reissner's fiber (RF) and its massa caudalis are strongly immunoreactive with the antiserum used. The wide intercellular spaces in the dorsal wall of the central canal and the ampulla, as well as the lumina of the (i) lacunae, (ii) modified vessels and (iii) blood capillaries are filled with a flocculent, strongly immunoreactive material. No immunoreactive material was found outside these structures. Thus, the blood capillaries appear to represent the only final target of RF-material arriving at the ampulla caudalis.Supported by Grant I 38259 from the Stiftung Volkswagenwerk, Federal Republic of Germany, Grant S-85-39 from the Dirección de Investigaciones, Universidad Austral de Chile, and Grant 6027 from Fondo Nacional de Desarrollo Científico y Tecnológico, Chile. The authors express their gratitude to Mrs. Elizabeth Santibáñez and Mr. Julio Lamilla for providing the lamprey larvae and to Mr. Humberto Molina for preparing the three-dimensional drawing  相似文献   
20.
To determine whether human B cells can be triggered to secrete interleukin 2 (IL-2), 19 tumor cell lines derived from patients with undifferentiated lymphomas of Burkitt's and non-Burkitt's types and 6 normal lymphoblastoid cell lines were tested. Cells were grown in the presence or absence of the new tumor promoter teleocidin, and culture supernatants were assayed for IL-2 activity using the standard CTLL-2 assay. Teleocidin (10 ng/ml) triggered IL-2 secretion in 7/8 (87%) EBV-negative lymphoma cell lines of American origin and in 6/6 (100%) normal lymphoblastoid cell lines, but in only 1/6 (16%) EBV-positive tumor cell lines of American origin. Teleocidin had no effect on 5/5 (0%) African Burkitt's cell lines. IL-2 secretion was not detected in control supernatants. IL-2 secretion correlated with the induction of IgM secretion and was linked to both EBV status and karyotype. The following similarities in the functional biological characteristics of T cell and B cell IL-2 suggest that B cell IL-2 is not a factor which mimics IL-2 activity in the CTLL-2 assay: (i) neutralization of IL-2 by anti-IL-2 monoclonal antibody (DMS-1); (ii) elution of IL-2 following its adsorption to CTLL-2 cells; (iii) determination of the MW of IL-2 by SDS-PAGE and Western blot analysis; and (iv) ability of B cell IL-2 to support T cell proliferation and blocking of this activity by anti-tac monoclonal antibody. cDNA probes for T cell IL-2, however, did not detect IL-2 mRNA in B cells. The cell lines were also found to constitutively express IL-2 receptors detected by anti-tac monoclonal antibody, and to secrete soluble IL-2 receptors measured by ELISA. Our results imply that under certain circumstances, B cells can be triggered to secrete IL-2 or an IL-2-like molecule and thus influence T cell activation and proliferation.  相似文献   
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