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41.
Role of midwives     
Dr. Alfano (New England Journal of Medicine 296: 1126, 1977) is certainly entitled to his personal opinions, but when they appear in a major publication in a setting that calls for factual information, they cannot go unchallenged. Midwives have played and continue to play a major part in maternal-infant services in many advanced European countries. Combined midwife-physician services in Sweden, Finland, Japan, Netherlands, Denmark, Norway, and Switzerland produced infant mortality rates in 1972 superior to those reported by Dr. Alfano for the Commonwealth of Massachusetts in 1974. Even in 1967 Sweden and the Netherlands (where most infants are delivered by midwives) had infant mortality rates, respectively, of 12.9 and 13.4/100 live births. These numbers, of course, do not mean that midwives are superior to doctors, but they do not seem to prove them inferior when they are employed in an appropriate setting. In Oregon (where certified nurse-midwives have been employed for some years) the professional midwife is found mainly in the "expensive" practices, so that if there is a "3rd-level of care," it is delivered to the well-to-do rather than the indigent. It is a little early to tell, but the impression around here is that although the quality of the birth experience may be changed by addition of midwives to an upper-middle-class practice, the outcome in terms of numbers of live babies is no different. This finding may not apply when 1 is dealing with the economically disadvantaged. A striking study from California demonstrated a definite improvement in fetal outcome when certified midwives were added to an established program and a tendency for the infant mortality rate to rise again when their services were discontinued for lack of funds. A similar program is under way in Oregon, but it is much too early for results to be apparent. This letter is not written in defense of midwives - it is a plea for balance and rationality. Medicine is no place for a territorial imperative. Only by calling on the expertise of all qualified members of a society can one hope to progress and to improve the human condition.  相似文献   
42.
In this work, the authors studied the morphology of the axillary and mediastinal lymph nodes and their efferent branches in the white rat (Rattus norvegicus). The main characteristics observed were: The presence of two groups of axillary lymph nodes, one in the lateral and the other in the medial portion, and the presence of two groups of mediastinal lymph nodes, one being ventrolateral and the other dorsoventral relating to cranial precava veins. Usually, in both sides, there is a lymphatic plexus dorsally to the jugulsubclavian angle, formed by reunion of internal jugular and subclavian trunks and the thoracic duct (to the left) or the right lymphatic trunk (to the right). From this plexus, one or two branches run off and flow into the venous jugulosubclavian angle. The subclavian trunk begins in the medial axillar lymph nodes and joins to the lymphatic plexus at the internal jugular trunk or at the thoracic duct or yet at the right lymphatic trunk according to the site, and finally it may link itself directly to the venous system. The mediastinal lymph nodes at the side send branches forming the right lymphatic trunk and branches adhering to the lymphatic plexus; the left lymph nodes join to the plexus or the thoracic duct.  相似文献   
43.
Co-encapsulated microcapsules containing three lipophilic bioactive components (LBCs) including fish oil, phytosterols and limonene were studied and compared with those containing only fish oil. Milk proteins (whey protein isolate and sodium caseinate in a ratio of 4:1) were used as wall materials. Results show that good quality microcapsules can be obtained at inlet temperature of 170 °C and outlet temperature of 70 °C, with the wall to core ratio of 4:1. There was no significant different (p > 0.05) in the microencapsulation efficiency and the oxidation indicators (PV and AV) after the accelerated storage for both types of microcapsules. However, the retention of EPA and DHA in the LBCs-microcapsules was significantly higher (p < 0.05) than the fish oil microcapsules. The phytosterols content was unchanged but loss of limonene occurred after storage. The LBCs-microcapsules had better flavor/odour profile than the fish oil microcapsules after drying and storage.  相似文献   
44.
    
International Journal on Software Tools for Technology Transfer - Formal methods have become a recommended practice in safety-critical software engineering. To be formally verified, a system should...  相似文献   
45.
    
By combining X‐ray and ultraviolet photoelectron spectroscopy, X‐ray excited Auger electron spectroscopy, and inverse photoemission spectroscopy, a detailed characterization of the chemical and electronic structure at the CdTe/(Zn,Mg)O interface is presented. In doing so, a novel approach to characterize the electronic structure of transparent conductive oxides, namely, to distinguish between optically and transport‐relevant states is presented. Consequently, “optical” and “electronic” band offsets at the CdTe/(Zn,Mg)O interface are derived and it is demonstrated that the “electronic” band offset is suitable for electron transport across the interface (a flat conduction band alignment of 0.02 ± 0.20 eV), while the “optical band offset” is not (a significant 0.48 ± 0.20 eV spike). The new approach can easily be applied to many other transparent conductive oxides and is thus of relevance for a large variety of optoelectronic applications involving transparent electrical contacts.  相似文献   
46.
    
β-Thalassemia is one of the most common genetically inherited disorders worldwide, and it is characterized by defective β-globin chain synthesis leading to reduced or absent β-globin chains. The excess α-globin chains are the key factor leading to the death of differentiating erythroblasts in a process termed ineffective erythropoiesis, leading to anemia and associated complications in patients. The mechanism of ineffective erythropoiesis in β-thalassemia is complex and not fully understood. Autophagy is primarily known as a cell recycling mechanism in which old or dysfunctional proteins and organelles are digested to allow recycling of constituent elements. In late stage, erythropoiesis autophagy is involved in the removal of mitochondria as part of terminal differentiation. Several studies have shown that autophagy is increased in earlier erythropoiesis in β-thalassemia erythroblasts, as compared to normal erythroblasts. This review summarizes what is known about the role of autophagy in β-thalassemia erythropoiesis and shows that modulation of autophagy and its interplay with apoptosis may provide a new therapeutic route in the treatment of β-thalassemia. Literature was searched and relevant articles were collected from databases, including PubMed, Scopus, Prospero, Clinicaltrials.gov, Google Scholar, and the Google search engine. Search terms included: β-thalassemia, ineffective erythropoiesis, autophagy, novel treatment, and drugs during the initial search. Relevant titles and abstracts were screened to choose relevant articles. Further, selected full-text articles were retrieved, and then, relevant cross-references were scanned to collect further information for the present review.  相似文献   
47.
    
NX210c is a disease-modifying dodecapeptide derived from the subcommissural organ-spondin that is under preclinical and clinical development for the treatment of neurological disorders. Here, using whole-cell patch-clamp recordings, we demonstrate that NX210c increased α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR)- and GluN2A-containing N-methyl-D-aspartate receptor (GluN2A-NMDAR)-mediated excitatory postsynaptic currents in the brain. Accordingly, using extracellular field excitatory postsynaptic potential recordings, an enhancement of synaptic transmission was shown in the presence of NX210c in two different neuronal circuits. Furthermore, the modulation of synaptic transmission and GluN2A-NMDAR-driven signaling by NX210c restored memory in mice chronically treated with the NMDAR antagonist phencyclidine. Overall, by promoting glutamatergic receptor-related neurotransmission and signaling, NX210c represents an innovative therapeutic opportunity for patients suffering from CNS disorders, injuries, and states with crippling synaptic dysfunctions.  相似文献   
48.
A smart and greener microwave approach to the selective oxidation of cyclohexene is reported whereby, depending on the reaction conditions, the epoxide (65% conversion, 75% selectivity), the enol (70% conversion, 80% selectivity) or the enone (>99% conversion, 89% selectivity) can be obtained in a short period of time ranging from 1 to 20 min. A cobalt-salen-SBA-15 material was employed as catalyst. The reported solventless microwave protocol was simple, greener and more efficient compared to any other reported cyclohexene oxidations.  相似文献   
49.
    
In this article are reviewed the principal oxygenated products that can be produced exclusively from synthesis gas either by a straight-run process or through the use of methanol that can be easily obtained from CO and H2. A comparison is made between the synthesis processes, the different catalysts and their performances. An approach of the mechanistic aspects is undertaken by considering the various mechanistic routes proposed for these reactions. It already now appears that such ways of obtaining these oxygenated products would allow to replace processes using olefins by processes using methanol and synthesis gas.  相似文献   
50.
G. Stanley Hall influenced several social movements that had great implications for child wellbeing: the Child Study, Parent Education, and Child Welfare Movements. However, while Hall laid much of the foundation for the field of scientific child study and policy-relevant research, his legacy is virtually nonexistent. The current article reviews the life and contributions of G. Stanley Hall, and the dual role Hall played in history as a revered leader of the Child Study Movement and a controversial figure in the landscape of early child psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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