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1.
Self-selected food intake of 15 reduced-obese women living in a metabolic ward was studied for 14 consecutive days to determine the effect of exercise and other metabolic and behavioral variables on energy intake. A choice of prepared food items were offered at breakfast, lunch and dinner, and a variety of additional food items were available continuously 24 h/day. Subjects performed either moderate intensity aerobic exercise (A-EX) (n = 8) expending 354 +/- 76 kcal/session or low intensity resistance weight training (R-EX)(n =7) expending 96 +/- kcal/session, 5 days/week. Mean energy intakes (kcal/day, +/- SEM) of the exercise groups were similar: 1867 +/- 275 for A-EX, 1889 +/- 294 for R-EX. Mean energy intakes of individuals ranged from 49 to 157% of the predetermined level required for weight maintenance. Resting metabolic rate per kg 0.75 and the Eating Inventory hunger score contributed significantly to the between subject variance in energy intake, whereas exercise energy expenditure did not. Regardless of exercise, eight women consistently restricted their energy intake (undereaters), and seven other consumed excess energy (overeaters). Overeaters were distinguished by higher Eating Inventory disinhibition (P = 0.023) and hunger (p = 0.004) scores. The overeaters' diet had a higher fat content 34 +/- 1% (p = 0.007). Also, overeaters took a larger percentage of their daily energy, than that of undereaters, 27 +/- 1 energy intake in the evening, 13 +/- 2%, compared to undereaters, 7 +/- 1% (p = 0.005). We conclude that the Eating Inventory is useful for identifying reduced-obese women at risk of overeating, and these individuals may benefit from dietary counseling aimed at reducing fat intake and evening snacking.  相似文献   
2.
We investigated the synaptic terminals of fibers originating in the ventroposteromedial thalamic nucleus (VPM) and projecting to the main input layers (IV/III) of the rat posteromedial barrel subfield. It was our aim to determine whether or not the subpopulation of vasoactive intestinal polypeptide (VIP)-immunoreactive neurons in these layers are directly innervated by the sensory thalamus. Anterograde tracing with Phaseolus vulgaris leucoagglutinin (PHA-L) and immunohistochemistry for VIP were combined for correlated light and electron microscopic examination. Columns of cortical tissue were well defined by barrel-like patches of PHA-L-labeled fibers and boutons in layers IV and III. Within these columns VIP-immunoreactive perikarya were located mainly in supragranular layers. Marked perikarya were also seen in infragranular layers, but their immunoreactivity was often weaker. Granular layer IV, which is the main terminal field for thalamic fibers, contained fewer VIP neurons than supragranular layers. In the light microscope, however, PHA-L-labeled fibers appeared to contact the somata or proximal dendrites of 60-86% of the layer IV VIP neurons . By contrast, only 18-35% of the VIP neurons in the supragranular layers, which receive a moderately dense projection from the VPM, appeared to be contacted. PHA-L-labeled boutons were seen close to 13-25% of infragranular VIP-positive cells. Electron microscopy showed that thalamic fibers formed at most four asymmetric synapses on a single layer IV, VIP-positive neuron. Although the proportion of VIP-positive neurons with labeled synapses was lower in supragranular layers, most of them shared multiple asymmetric synapses with labeled thalamic fibers. Up to six labeled synapses were seen on individual VIP neurons in layer III. We conclude that subpopulations of VIP-immunoreactive neurons, located in layers IV, III, and II are directly innervated by the VPM. These neurons may be involved in the initial stages of cortical processing of sensory information from the large, mystacial vibrissae. Since VIP is known to be colocalized with the inhibitory transmitter GABA, it is likely that VIP neurons participate in the shaping of the receptive fields in the barrel cortex.  相似文献   
3.
Over the past seven years, Columbia-Presbyterian Medical Center has been planning and implementing an integrated academic information management system. Accomplishments to date include establishing an institutional information architecture, installing a campus-wide network of workstations, recruiting the staff needed to develop and implement the system, and developing various applications. This paper presents the rationale and steps involved in these accomplishments, as well as data on use of the system so far.  相似文献   
4.
While abundant clinical and angiographic data are available regarding features of acute or abrupt closure at the site of balloon angioplasty, little morphologic information is available. This study discusses morphologic-histologic causes for acute closure after angioplasty in 130 necropsy patients. Intimal-medial flaps, elastic recoil, and primary thrombosis were the three leading morphologic causes for closure. Data were subdivided into time categories: abrupt (< 1 day), acute (< 1 week), and early (< 1 month). Intimal-medial flaps remained the most common cause for angioplasty closure despite time from angioplasty to documented occlusion. Morphologic recognition of types and frequencies of angioplasty closure are discussed, and specific mechanical, pharmacologic, or combined treatments are reviewed.  相似文献   
5.
Ku is a heterodimeric protein composed of 86 and 70 kDa subunits that binds preferentially to the double-stranded ends of DNA. Recent molecular characterization of ionizing-radiation sensitive (IRs) mutants belonging to the XRCC5 complementation group demonstrated the involvement of Ku in DNA double-strand break (DSB) repair and lymphoid V(D)J recombination. Here, we describe the isolation of a full-length hamster cDNA encoding the large subunit of the Ku heterodimer and demonstrate that the stable expression of this cDNA can functionally restore IR, Ku DNA end-binding activity and V(D)J recombination proficiency in the Chinese hamster IRs sxi-3 mutant. Moreover, we also demonstrate that sxi-3 cells are hypersensitive to etoposide, a DNA topoisomerase II inhibitor, and that resistance to this drug was restored by the Ku86 cDNA. These experiments suggest that a defect in the large subunit of the heterodimeric Ku protein is the sole factor responsible for the known defects of sxi-3 cells and our data of further support the role of Ku in DNA DSB repair and V(D)J recombination.  相似文献   
6.
A total of 1010 dry cows and pregnant heifers was randomly selected from 25 dairy farms near Guelph, Ontario, Canada to receive either a controlled-release capsule of monensin or a placebo at 3 wk prior to expected calving. Serum samples were obtained at the time of treatment administration, and both serum and milk samples were collected at wk 1, 2, 3, 6, and 9 postcalving. The threshold used to define subclinical ketosis was selected a priori at a concentration of > or = 1200 mumol/L of beta-hydroxybutyrate. Using this threshold, the prevalence and incidence of subclinical ketosis were significantly reduced (50%) by monensin treatment. The duration of subclinical ketosis for cows that had been treated with monensin was also shorter than that for cows treated with the placebo. Monensin treatment significantly reduced the incidence of subclinical ketosis when the threshold was defined using higher concentrations of serum beta-hydroxybutyrate (1400 and 2000 mumol/L). In addition, monensin significantly reduced the prevalence of positive milk ketone tests.  相似文献   
7.
BACKGROUND: Clinical manifestations and course of sickle-cell anemia are variable. Knowledge about the factors, possibly geographic, that influence prognosis are still scanty. POPULATION AND METHODS: Data of hospitalization and management of children with sickle-cell disease were studied during two years (1992-1993) in the Pediatric Unit of Libreville Hospital. They concerned 205 admissions of 171 children and 131 outpatients. RESULTS: The main causes of hospitalization were: acute anemia (36 cases before the age of 5 years); painful crisis whose frequency increased with age (23% before 5 years, 35% between 5 and 10, 42% after 10 years); infections, essentially pulmonary occurring early, and bone infections at any age. Eight children died (because a complication of their disease). Among the 131 outpatients, half were detected because pyrexia, anemia and/or more often "hand-foot syndrome". More than 60% had hepatomegaly, one third still had splenomegaly after five years of age and more than one third was icteric. More than half children older than ten years had growth disorders. Mean hemoglobin level was 7 g/dL. 21 of the 83 tested children for HBsAg were positive and only one out of 79 was positive for HIV. CONCLUSIONS: Clinical manifestations and course of sickle-cell anemia in our patients are similar to those reported in Congolese children. Genetic and environmental factors may be responsible for differences with children from other, in particular French, cohorts.  相似文献   
8.
手机测试中一个主要关心的问题是它在很宽动态范围内的响应情况。与模拟或TDMA手机比较而言,CDMA手机尤其如此。因为CDMA手机在很宽的带宽范围内具有80dB动态范围,这种大动态范围是CDMA技术的一个独特优点,CDMA手机和基站的发射功率平均起来要比其他技术都低。由于这种手机能收到-104dBm以下的信号,因此,规定频谱内的噪声会影响最低性能标准,如TIA/EIA-98C中列出的多项测试,所以了解干扰对CDMA手机接收机测试的影响是非常重要的。手机测试易受噪声影响在考查噪声对手机测试的影响之前首先应了解手机的结构。手机里既有…  相似文献   
9.
In the realm of soft nanotechnology, hydrogel micro‐ and nanoparticles represent a versatile class of responsive materials. Over the last decade, our group has investigated the synthesis and physicochemical properties of a variety of synthetic hydrogel particles. From these efforts, several particle types have emerged with potentially enabling features for biological applications, including nanogels for targeted drug delivery, microlenses for biosensing, and coatings for biomedical devices. For example, core/shell nanogels have been used to encapsulate and deliver small interfering RNA to ovarian cancer cells; nanogels used in this fashion may improve therapeutic outcomes for a variety of macromolecular therapeutics. Microgels arranged as multilayers on implantable biomaterials greatly minimize the host inflammatory response to the material. Furthermore, the triggered release of drugs (i.e., insulin) has been demonstrated from similar assemblies. The goal of this feature article is to highlight developments in the design of responsive microgels and nanogels in the context of our recent efforts and in relation to the community that has grown up around this fascinating class of materials.  相似文献   
10.
The course of two neonates and one 4-month-old infant with laboratory and clinical evidence of central hypothyroidism is described. All three presented with failure to thrive and improved after L-T4 therapy. Early recognition and treatment of newborns and infants with central hypothyroidism is important to maximize the potential for growth and development. Two of the three infants have been documented to have transient central hypothyroidism of hypothalamic origin, not previously reported.  相似文献   
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