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131.
132.
Peripheral nerve depends on glucose oxidation to energize the repolarization of excitable axonal membranes following impulse conduction, hence requiring high-energy demands by the axon at the node of Ranvier. To enter the axon at this site, glucose must be transported from the endoneurial space across Schwann cell plasma membranes and the axolemma. Such transport is likely to be mediated by facilitative glucose transporters. Although immunohistochemical studies of peripheral nerves have detected high levels of the transporter GLUT1 in endoneurial capillaries and perineurium, localization of glucose transporters to Schwann cells or peripheral axons in vivo has not been documented. In this study, we demonstrate that the GLUT1 transporter is expressed in the plasma membrane and cytoplasm of myelinating Schwann cells around the nodes of Ranvier and in the Schmidt-Lanterman incisures, making them potential sites of transcellular glucose transport. No GLUT1 was detected in axonal membranes. GLUT3 mRNA was expressed only at low levels, but GLUT3 polypeptide was barely detected by immunocytochemistry or immunoblotting in peripheral nerve from young adult rats. However, in 13-month-old rats, GLUT3 polypeptide was present in myelinated fibers, endoneurial capillaries, and perineurium. In myelinated fibers, GLUT3 appeared to be preferentially expressed in the paranodal regions of Schwann cells and nodal axons, but was also present in the internodal aspects of these structures. The results of the present study suggest that both Schwann cell GLUT1 and axonal and Schwann cell GLUT3 are involved in the transport of glucose into the metabolically active regions of peripheral axons.  相似文献   
133.
Pediatric acquired immunodeficiency syndrome (AIDS) is becoming more common. Moreover, human immunodeficiency virus (HIV) positive status in multiple family members is common and complicates disease management. Practitioners treating these children are often unaware of the effect of the virus on the child's psychological, cognitive, and emotional functioning. In addition, children with AIDS frequently come from families facing pressing social problems, including homelessness, poverty, and drug addiction. HIV-positive children thus confront such diverse issues as the deterioration of developmental skills, social ostracism, and the possibility of imminent death, placing them in a socioemotional crisis. This paper presents a comprehensive psychotherapeutic intervention for such children.  相似文献   
134.
OBJECTIVE: The aim of this study was to determine the feasibility of a novel saliva-activated bioadhesive drug delivery system of lidocaine hydrochloride as a viable alternative to infiltration anesthesia in dentistry. STUDY DESIGN: The study was carried out in three stages. First, the drug delivery system (DDS) was subjectively evaluated for adherence to the gingival mucosa and peak effect of anesthesia. In the second stage, a comparative subjective and objective evaluation of the DDS with a marketed topical gel preparation was carried out. Finally an open label, nonblinded clinical trial was carried out using the exodontia model. A total of 49 extractions were attempted in 41 patients. The effect of the following variables was investigated in the study: (1) jaw (maxillary and mandibular), (2) overall mobility, (3) position-notation of tooth (1, 2, 3, 4 ...). The positive extractions were statistically analyzed by the t test comparison of means of two independent variables. RESULTS: Subjective evaluation revealed that the DDS adheres to the gingiva within a minute and produces peak effect in 15 minutes. Comparative study revealed that the DDS produces greater depth of anesthesia than the marketed topical gel. Of 49 extractions attempted with the DDS, 40 were successful, giving an efficacy of 81.63%. CONCLUSION: The novel saliva-activated bioadhesive drug delivery system of lidocaine hydrochloride exhibits potential as a feasible alternative to infiltration anesthesia in dentistry.  相似文献   
135.
OBJECTIVES: We hypothesized that depressive symptoms not meeting full standard criteria for Major Depression would be associated with significant functional impairment among older adults over the course of a 13-year follow-up interval. Specifically, we developed criteria for a form of depression whose core symptoms did not include sadness or dysphoria. DESIGN: Population-based 13-year follow-up survey. SETTING: Community-dwelling adults living in East Baltimore in 1981. PARTICIPANTS: Subjects were the 1612 participants of the Baltimore sample of the Epidemiologic Catchment Area Program aged 50 years and older at the initial interview in 1981. MEASUREMENTS: The subjects were sorted into four categories based on their responses at baseline: (1) persons meeting standard criteria for Major Depression; (2) persons meeting alternative criteria for depression with dysphoria or (3) without dysphoria; and (4) a comparison category of persons not meeting any criteria for depression ("noncases"). The mortality and functional status of each group were compared after a 13-year follow-up interval. RESULTS: Compared with non-cases, participants aged 50 years and older who reported depressive symptoms but who denied sadness or dysphoria (nondysphoric depression) were at increased risk for death (relative risk (RR) = 1.70; 95% confidence interval (CI) (1.09, 2.67)), impairment in activities of daily living (RR = 3.76; 95% CI (1.73, 8.14)), impairment in instrumental activities of daily living (RR = 5.07; 95% CI (2.24, 11.44)), psychologic distress (RR = 3.68; 95% CI (1.47, 9.21)), and cognitive impairment (RR = 3.00; 95% CI (1.31, 6.89)) after a 13-year follow-up interval. The findings were not wholly explained by potentially influential baseline characteristics such as age, education, selected comorbid medical conditions, and functional status. CONCLUSION: Among adults aged 50 years and older, nondysphoric depression may be as important as Major Depression in relation to the development of functional disability and other long-term outcomes.  相似文献   
136.
Two subunits of the yeast ATP synthase have been isolated. Subunit e was found loosely associated to the complex. Triton X-100 at a 1% concentration removed this subunit from the ATP synthase. The N-terminal sequencing of subunit i has been performed. The data are in agreement with the sequence of the predicted product of a DNA fragment of Saccharomyces cerevisiae chromosome XIII. The ATP18 gene encodes subunit i, which is 59 amino acids long and corresponds to a calculated mass of 6687 Da. Its pI is 9.73. It is an amphiphilic protein having a hydrophobic N-terminal part and a hydrophilic C-terminal part. It is not apparently related to any subunit described in other ATP synthases. The null mutant showed low growth on nonfermentable medium. Mutant mitochondria display a low ADP/O ratio and a decrease with time in proton pumping after ATP addition. Subunit i is associated with the complex; it is not a structural component of the enzyme but rather is involved in the oxidative phosphorylations. Similar amounts of ATP synthase were measured for wild-type and null mutant mitochondria. Because 2-fold less specific ATPase activity was measured for the null mutant than for the wild-type mitochondria, we make the hypothesis that the observed decrease in the turnover of the mutant enzyme could be linked to a proton translocation defect through F0.  相似文献   
137.
In this study,we report on the realization of ultraviolet response enhancement in PV cells through the structure of ITO/SiO2/np-Silicon frame(named as SINP),which was fabricated by the state of the art processing.The fabrication process consists of thermal diffusion of phosphorus element into p-type texturized crystal Si wafer,thermal deposition of an ultra-thin silicon dioxide layer(15—20) at low temperature,and subsequent deposition of thick In2O3:SnO2(ITO) layer by RF sputtering.The structure,morphology...  相似文献   
138.
139.
To elucidate the effect of feeding of butyric acid on disaccharidase activities, the specific activities of the disaccharidases were measured in the intestinal mucosa and kidney cortex of control and diabetic rats. Diabetes was induced in rats using streptozotocin. Rats were fed with basal diet containing wheat bran (5%) as a source of insoluble dietary fiber and guar gum (2.5%) as a source of soluble dietary fiber. The experimental group received butyric acid at 250, 500 and 750 mg/kg body weight/day. Increased activities of intestinal maltase, sucrase and lactase in diabetic rats were significantly reduced in fiber-fed diabetic group. Supplementation of butyric acid at 500 mg/kg body weight/day showed a further decrease in their activities. The activity of disaccharidases in renal tissue was decreased in diabetic rats and was significantly improved in fiber-fed diabetic group. Butyric acid feeding at 500 mg/kg body weight/day showed further improvement in their activities.  相似文献   
140.
Additional energy expenses due to stretching of the elastic elements of anti-loading suit (ALS) "Penguin" as a whole (shoulders-feet) or only its lower part (waist-feet) in the course of cyclic leg movements were measured in five female and five male volunteers. ALS design enabled tensometric monitoring of efforts applied to specific elastic elements, and total efforts applied to the shoulder or pelvic girdles separately. Energy spend were determined with the indirect calorimetric techniques from the data of the expired air analysis. Registered were electromyograms of m. longus spinae, femoral extensor (m. biceps femoris) and femoral flexor (m. rectus femoris), and m. gastrocnemius. On the first stage, bicycle ergometer was pedaled w/o loading with a frequency of 60 cycles/min. The next stage included testing by incremental loading in which pedaling ceased at the pulse rate of 150/min. Results of the experiments that did not require stretching elastic parts of the suit and in which the total strain effort made up 20 to 25 kg and 15 to 16 kg by males and females, respectively, were compared. It was ascertained that ALS enhanced metabolism during motion by 20 to 30%; however, there was no significant difference in energy expenses when loaded by the whole suit or only its lower part.  相似文献   
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