The rostral epithelium of a newly metamorphosed juvenile of Branchiostoma floridae was examined at the EM level to confirm previous reports on its sensory cells. The majority of the sensory cells are of three types: two type I variants, with simple collars of unbranched microvilli surrounding their cilia, and one kind of type II cell, with an extended collar of repeatedly branched microvilli. The two type I variants differ in the structure and arrangement of the microvilli, basal body and rootlet, and the length of the cilium. Both variants are probably primary sensory cells (i.e. each has its own axon), but the data supporting this conclusion are much better for one variant than for the other. Type II cells are secondary sensory cells, with synaptic terminals borne on short extensions of the cell body. The presence of degenerating type II cells suggests that they may be subject to a regular process of loss and renewal. The results do not resolve the evolutionary issue of how amphioxus sensory cells relate to the epithelial sensory and receptor cells of vertebrates. Being primary, the type I cells resemble the supposed ancestral type more closely than do type II cells. Type II cells may be chemosensory, however, and should not be ruled out a priori as possible homologues of either primary or secondary chemosensory cells in vertebrates.
BackgroundThe hierarchical medical system (HMS) refers to the classification of treatment according to disease priorities based on severity and difficulty to promote the fairness of medical services for residents, which is regarded as the key to the success of medical reform in China.MethodsIn the past decade of “New Medical Reform,” the efficiency of HMS, including secondary and tertiary hospitals and primary healthcare centers (PHCs), was measured horizontally and vertically by employing the combination of an output-oriented superefficiency slack-based model-data envelopment analysis (SE-SBM-DEA) model with the Malmquist total factor productivity index (MTFP). In the second stage, the overall technical efficiency (OTE) scores were regressed against a set of environmental characteristics and several managerial factors through bootstrapping truncated regression.ResultsOn average, the OTE score in tertiary hospitals was 0.93, which was higher than that in secondary hospitals and PHCs (0.9 and 0.92, respectively). In terms of trend, the OTE of tertiary hospitals declined at first and then increased. The opposite was true of secondary hospitals, in which the APC of the OTE was 10.82 and −3.11% in early and late 2012, respectively. The PHCs generally showed a fluctuating downward trend. In the aspects of productivity, all institutions showed a downturn by an annual average rate of 2.73, 0.51, and 2.70%, respectively. There was a significant negative relationship between the ratio of outpatients to inpatients and tertiary hospitals. Additionally, the medical technical personnel per 1,000 population negatively affected PHCs. In contrast, the GDP per capita had a significantly positive effect on tertiary hospitals, and the number of beds per 1,000 population positively influenced PHCs.ConclusionThe efficiency of medical institutions at various levels in HMS was unbalanced and took the form of an “inverted pyramid.” Multilateral factors influence the efficiency of HMS, and to address it, multi-intervention packages focusing on sinking high-quality medical resources and improving healthcare capacity, and guiding hierarchical medical practice should be adopted.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.