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81.
A pilot presented with a 2-month history of dysgeusia following treatment for sinusitis. This was accompanied by a 30-lb weight loss due to the abnormal taste of most foods. An extensive evaluation failed to demonstrate a cause for the malady. The clinical course and diagnostic evaluation were consistent with a diagnosis of idiopathic dysgeusia. The clinical presentation, evaluation, and diagnosis of a pilot with dysgeusia are discussed.  相似文献   
82.
83.
Incidence of primary and secondary female infertility is analyzed from results of 10-year follow-up of 3478 couples married in Ryazan, a city in Central Russia. Data of sociohygienic studies of epidemiology of sterility should be taken into consideration when planning measures aimed at prevention of reproductive disorders in various sociodemographic strata of population.  相似文献   
84.
A surgeon has many options available to aid in the closure of abdominal wall defects in the elective setting. In the emergent setting, active infection or contamination increases the likelihood of infection of permanent prosthetic material and limits the surgical options. In such settings, we have used absorbable mesh (Dexon) as an adjunct to fascial closure until the acute complications resolve. To evaluate the effectiveness of this technique, we reviewed the outcome of such closures in 26 critically ill patients. Between July 1987 and June 1993, 26 patients were identified who had placement of absorbable mesh as part of an emergent laparotomy at a major urban trauma center. Through a retrospective chart review, the incidence of complications and outcome of the closure were tabulated. Seven patients were initially operated on for trauma. Two of the patients had mesh placement at their initial procedure secondary to fascial loss from trauma. The remainder of the patients hd mesh placement during a subsequent laparotomy for complications related to their initial procedure. Indications for these laparotomies included combinations of wound dehiscence, intra-abdominal abscess, anastomotic disruption, and perforation. Mesh placement in patients with intra-abdominal infection created effectively open abdominal wounds that allowed continued abdominal drainage, but required extensive wound care. Despite the absorbable nature of the mesh and often prolonged hospital stay in these ill patients, none of them required reoperation for dehiscence, recurrence of intra-abdominal abscess, or infection of the mesh.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
85.
When stimulating the peripheral and of the right n. vagus in anesthetised cats, the sinus arrhythmia occurred in case the vagal bursts were beyond the limits of the controlled bradycardia range. I. v. administration of met-enkephaline suppressed the arrhythmia immediately but the latter reappeared within 15-20 minutes. The data obtained suggests a biphasic effect of met-enkephaline upon the vagal sinus arrhythmia.  相似文献   
86.
The paper aims to give an extensive overview of the energy constraints in Wireless Sensor Networks and the power management strategies used in the literature as power efficiency is considered as the most challenging issue in WSNs. The paper opted for an investigative study of the adaptive systems that represent efficient solutions to deal with environmental and context changes in wireless sensor Networks. It provides thorough insights about how change has brought about the use of adaptive systems in WSNs. It proposes a new adaptation technique inspired from combining adaptation in different layers and can be more efficient and performing. This paper fulfills an identified need to study reconfigurable systems to achieve power efficiency, as a sensor node is power constrained.  相似文献   
87.
Tumor necrosis factor-alpha (TNFalpha)-induced cell death involves a diverse array of mediators and regulators including proteases, reactive oxygen species, the sphingolipid ceramide, and Bcl-2. It is not known, however, if and how these components are connected. We have previously reported that GSH inhibits, in vitro, the neutral magnesium-dependent sphingomyelinase (N-SMase) from Molt-4 leukemia cells. In this study, GSH was found to reversibly inhibit the N-SMase from human mammary carcinoma MCF7 cells. Treatment of MCF7 cells with TNFalpha induced a marked decrease in the level of cellular GSH, which was accompanied by hydrolysis of sphingomyelin and generation of ceramide. Pretreatment of cells with GSH, GSH-methylester, or N-acetylcysteine, a precursor of GSH biosynthesis, inhibited the TNFalpha-induced sphingomyelin hydrolysis and ceramide generation as well as cell death. Furthermore, no significant changes in GSH levels were observed in MCF7 cells treated with either bacterial SMase or ceramide, and GSH did not protect cells from death induced by ceramide. Taken together, these results show that GSH depletion occurs upstream of activation of N-SMase in the TNFalpha signaling pathway. TNFalpha has been shown to activate at least two groups of caspases involved in the initiation and "execution" phases of apoptosis. Therefore, additional studies were conducted to determine the relationship of GSH and the death proteases. Evidence is provided to demonstrate that depletion of GSH is dependent on activity of interleukin-1beta-converting enzyme-like proteases but is upstream of the site of action of Bcl-2 and of the execution phase caspases. Taken together, these studies demonstrate a critical role for GSH in TNFalpha action and in connecting major components in the pathways leading to cell death.  相似文献   
88.
Methylcobalamin (MeCbl) and adenosylcobalamin (AdoCbl) are coenzymes for methionine synthase and methylmalonyl‐CoA mutase, respectively. Hydroxylcobalamin (HOCbl) and cyanocobalamin (CNCbl) are frequently used for supplementation. MeCbl and AdoCbl have recently emerged as alternative forms in supplements. In the light of metabolic transformation of Cbl into its cofactor forms, this review discusses current evidence on efficacy and utility of different Cbl forms in preventing or treating Cbl deficiency. Cbl‐transporting proteins bind and mediate the uptake of all aforementioned forms of Cbl. After internalization and lysosomal release, Cbl binds to the cytosolic chaperon MMACHC that is responsible for (i) flavin‐dependent decyanation of [CN‐Co3+]Cbl to [Co2+]Cbl; (ii) glutathione‐dependent dealkylation of MeCbl and AdoCbl to [Co2+/1+]Cbl; and (iii) glutathione‐dependent decyanation of CNCbl or reduction of HOCbl under anaerobic conditions. MMACHC shows a broad specificity for Cbl forms and supplies the Cbl2+ intermediate for synthesis of MeCbl and AdoCbl. Cobalamin chemistry, physiology, and biochemistry suggest that MeCbl and AdoCbl follow the same route of intracellular processing as CNCbl does. We conclude that supplementing MeCbl or AdoCbl is unlikely to be advantageous compared to CNCbl. On the other hand, there are obvious advantages of high parenteral doses (1–2 mg) of HOCbl in treating inborn errors of Cbl metabolism.  相似文献   
89.
OBJECTIVE: To compare the effect of tropicamide alone and tropicamide-phenylephrine on anterior chamber flare and cell measurements obtained with a laser flare-cell meter. DESIGN: Prospective study. SETTING: Gimbel Eye Centre, Calgary. SUBJECTS: Twenty white subjects (10 with blue irides and 10 with brown irides) aged 24 to 45 (mean 30.2) years without any known systemic or ocular disease. INTERVENTIONS: Laser flare-cell measurements were obtained 30 minutes after pupillary dilation with 1% tropicamide in one eye and a combination drop of 0.8% tropicamide and 5% phenylephrine in the other eye. The average of five readings was taken for each eye. OUTCOME MEASURES: Flare and cell measurements. RESULTS: There was no statistically significant difference in flare photon count or cell count between the eyes dilated with tropicamide and those dilated with tropicamide-phenylephrine. In addition, iris colour was not found to have a significant effect on flare and cell measurements. CONCLUSIONS: Our results suggest that pupillary dilation for laser flare-cell measurements can be done with either mydriatic agent in healthy white subjects of any eye colour without significant effects on the measurements. Further study is needed to determine whether the same is true in older subjects.  相似文献   
90.
The objective of this study was to determine the number of Sertoli cells per boar, daily sperm production, and germ cell yield per type A spermatogonium in mature Whitecross, Meishan, and West African boars. The paired parenchymal mass was greatest in the Whitecross boars and greater in Meishan than in West African boars. Daily sperm production per boar (x 10(9)) differed significantly (P < 0.05) among breeds (Whitecross: 12.5 +/- 1.5; Meishan: 6.0 +/- 0.5; West African: 2.9 +/- 0.3). Daily sperm production per boar was positively (P < 0.01) correlated with parenchymal mass (r = 0.97), number of A spermatogonia per testis (r = 0.88), and Sertoli cells per testis (r = 0.87). Daily sperm production per gram of testis was similar among breeds. Number of Sertoli cells and number of type A spermatogonia per boar were greater for the Whitecross but similar in the Meishan and West African boars. The number of Stage VII germ cells per Sertoli cell was greater (P < 0.05) in the Meishan (39.08 +/- 5.07), but similar in the Whitecross (19.91 +/- 1.62) and West African boars (15.81 +/- 2.43). The number of type A spermatogonia per testis was highly and positively (P < 0.01) correlated with number of Sertoli cells per testis (r = 0.95), and parenchymal mass (r = 0.88). There was a trend for the spermatid yield per type A spermatogonium to be greater in the Meishan boars, and this ratio was positively correlated with spermatid:Sertoli cell ratio (r = 0.62) but not with daily sperm production per boar or Sertoli cells per testis. No significant germ cell degeneration occurred during the long meiotic prophase, but the loss of progeny during postprophase of meiosis averaged 32.62% across all breeds. Germ cell degeneration was similar (P > 0.05) across breeds during spermiogenesis, and on average amounted to 8.6%. The increased number of type A spermatogonia and of Sertoli cells associated with larger testes for the Whitecross over West African or Meishan boars is sufficient to explain the higher sperm production in the Whitecross. However, the lower index of degeneration and more efficient Sertoli cell function in Meishan boars results in the daily sperm production being intermediate between that of the Whitecross and West African boars.  相似文献   
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