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991.
Twenty-three patients with infective endocarditis received intramuscular clindamycin (Cleocin) for treatment. Thirteen had acute Staphylococcus (S.) aureus endocarditis but none had involvement of the aortic valve. Eleven of these 13 infections were heroin-related and involved the tricuspid valve.Twenty-one patients were successfully treated. Two patients with heroin-related S. aureus infection failed to respond to intramuscularly administered clindamycin, but responded to retreatment with methicillin. There have been 34 reported cases of endocarditis treated with clindamycin. Although 80 percent of all cases due to staphylococci responded favorably, almost all were heroin-related tricuspid valve infections. In addition 91 percent of cases due to aerobic streptococci responded but, surpisingly, treatment failed in three of four cases of anaerobic endocarditis. Although clindamycin can be useful in streptococcal endocarditis and in some cases of heroin-related S. aureus tricuspid endocarditis, caution should be exercised in its use. It is "less" bactericidal than the penicillins or cephalosporins, and organisms have become resistant during treatment. Furthermore, patients with anaerobic endocarditis have not responded well, and data are not available to recommend administration of clindamycin for acute S. aureus infections engrafted on the aortic or mitral valve.  相似文献   
992.
Cross infection has become a serious risk to hospitalized patients. Potential sources of infection by anaesthetic apparatus and equipment and the danger arising from disregard of proper asepsis are discussed. Prophylactic and hygienic measures to minimize these hazards are reviewed. Since patients receiving intensive therapy are particularly are risk very high hygienic standards are a "must" in these units. The need for thoroughly and regularly checking all equipment for contamination is emphasized.  相似文献   
993.
Three cases of middle ear and mastoid neoplasms are reported as "adenomatous tumors" since in their search of the literature the authors did not find any previously described lesions with a similar histologic appearance and benign biologic behavior. Microscopically, all three tumors are similarly composed of solid cords and nests of closely-packed small cells having an epithelial appearance. Two distinct cell types are present: cuboidal cells, arranged in a rudimentary gland-like pattern, and angular cells forming irregular nests with no distinct pattern. All three tumors developed in patients in their 20's, over a period of months with minimal symptoms; yet in all of the lesions the tympanic membrane was intact at the time of initial examination. None of the neoplasms was diagnosed preoperatively, and, once removed, all three tumors were pathologic enigmas and therapeutic problems in view of the initial and subsequent consultant pathologic opinions; nevertheless, total local excision with preservation of the tympanic membrane would appear to be safe treatment in these cases. The term "adenomatous tumor" is applied to these three neoplasms because: 1. a true glandular epithelial origin warranting the term adenoma or adenocarcinoma cannot be proven; and 2. the biologic behavior and prognosis is not necessarily reflected by the histologic appearance. A more specific term reflecting the origin and behavior of these tumors does not appear possible without the study of further cases.  相似文献   
994.
995.
In this paper, we present a nonray‐tracing technique for evaluating the three dimensional distribution of the refractive index values inside polymeric fibres. This technique, named ‘single‐frame computed‐tomography (SFCT)’, is applied to digital holography. A comparative study between the calculated optical phase values using ordinary tomography and SFCT is carried out, and a negligible deviation is detected. The proposed technique is used to determine the three‐dimensional refractive index profile of isotactic Polypropylene fibres, IPP. The variation of the optical properties is measured before, during and after the formation of the necking phenomenon. In addition, SFCT technique is applied to the online determination of the change of the optical properties of IPP fibres. Holograms are given for illustration.  相似文献   
996.
Since Type 1 diabetes (T1DM) occurs when β-cells mass is reduced to less than 20% of the normal level due to autoimmune destruction of cells resulting in the inability to secrete insulin, preservation or replenishment of the functional β-cells mass has become a major therapeutic focus for this diabetic type treatment. Thus, this 4-week work plan was designed to determine which mesenchymal stem cells (MSCs) type is more appropriate to alleviate pancreatic hazards resulting from diabetes induction; via tracking a comparative study between MSCs derived from adipose tissue (AD-MSCs) and from bone marrow (BM-MSCs) in management of T1DM considering their immunomodulatory, anti-apoptotic and antioxidative roles. Rats were divided randomly into 4 groups; control, STZ-diabetic (D), D+AD-MSCs, and D+BM-MSCs groups. Both stem cells types in this study were allogenic. Herein, both oxidative stress and antioxidant markers were evaluated using colorimetric analysis, while inflammatory, immune and apoptotic markers were assessed through flow cytometric analysis. Results showed that diabetic rats treated with either AD-MSCs or BM-MSCs exhibited marked pancreatic antioxidant and anti-inflammatory activities that were able to initiate pancreatic immunomodulation and reducing β-cells apoptotic death, thus, help to restore their normal insulin secretion and hypoglycemic abilities. However, AD-MSCs injection was shown to be superior as a pancreatic regenerative tool in overcoming diabetes; owing to their marked antioxidant, anti-inflammatory, immunomodulatory, and anti-apoptotic characteristics over BM-MSCs treatment.  相似文献   
997.
本文研究了环境温度恒定为25℃、相对湿度为49%、体积为0. 01 m L的液滴在-20℃裸铜底板的冻结实验,发现在附加交流磁场强度分别为2. 0×10-3、2. 5×10-3、3. 0×10-3、3. 5×10-3、4. 0×10-3、4. 5×10-3、5. 0×10-3、5. 5×10-3、6. 0×10-3T的作用下,液滴结晶过冷度增大,最大过冷度提高了2. 08℃;但附加磁场会减小成核驱动力;相比无磁场情况下,液滴冷凝时间减少,凝结粒径相比无磁场下较小。通过对在相同温湿度下自然对流条件的冷铜底板结霜可视化研究发现,由于附加磁场使极性水分子有序的在底板排列,较无磁场下液滴结晶过程熵增更小,在宏观上呈现液滴有序排列。此外,实验发现在0~6×10-3T的磁场强度范围,随着磁场强度的增大,平板单位面积结霜量减小,单位面积结霜量与交流磁场强度有较高的相关性,得到了拟合关...  相似文献   
998.
The use of carbon fibre‐based polymeric composites in bicycle components has dramatically increased in the last few decades. This paper presents the results of fatigue and impact testing on bicycle forks that are known to have quality‐related manufacturing defects. In the investigation performed, acoustic emission testing is used to monitor crack growth during fatigue loading and impact. The results show three distinct stages in composite fatigue failure related to initiation, propagation and final growth. Implications of the results on design and testing of composite bicycle components are addressed pointing to a greater need in understanding current design procedures.  相似文献   
999.
OBJECTIVES: This study describes the development status of 127 homeless and 91 low-income housed infants and toddlers. METHODS: The Bayley Scales of Infant Development and the Vineland Screener were used to gather data. RESULTS: There were no differences between homeless and low-income housed children. However, younger children in both groups performed better than the older children on most summary scores. CONCLUSIONS: Homeless and low-income housed children did not differ in their cognitive and motor skills. However, older children scored lower than younger children on most measures of development status, suggesting that the cumulative effects of poverty may increase with time.  相似文献   
1000.
The transport mechanisms of Ambystoma proximal tubule that mediate transcellular Cl- absorption linked to Na+ were investigated in isolated perfused tubules using Cl--selective and voltage-recording microelectrodes. In control solutions intracellular activity of Cl- (aiCl) is 11.3 +/- 0.5 mm, the basolateral (V1), apical (V2), and transepithelial (V3) potential differences are -68 +/- 1.2 mV, +62 +/- 1.2 mV and -6.4 +/- 0.3 mV, respectively. When Na+ absorption is decreased by removal of organic substrates from the lumen, aiCl falls by 1.3 +/- 0.3 mm and V2 hyperpolarizes by +11.4 +/- 1.7 mV. Subsequent removal of Na+ from the lumen causes aiCl to fall further by 2.3 +/- 0.4 mm and V2 to hyperpolarize further by +15.3 +/- 2.4 mV. The contribution of transporters and channels to the observed changes of aiCl was examined using ion substitutions and inhibitors. Apical Na/Cl or Na/K/2Cl symport is excluded because bumetanide, furosemide or hydrochlorothiazide have no effect on aiCl. The effects of luminal HCO-3 removal and/or of disulfonic stilbenes argue against the presence of apical Cl-base exchange such as Cl-HCO3 or Cl-OH. The effects of basolateral HCO-3 removal, of basolateral Na+ removal and/or of disulfonic stilbenes are compatible with presence of basolateral Na-independent Cl-base exchange and Na-driven Cl-HCO3 exchange. Several lines of evidence favor conductive Cl- transport across both the apical and basolateral membrane. Addition of the chloride-channel blocker diphenylamine-2-carboxylate to the lumen or bath, increases the aiCl by 2.4 +/- 0.6 mm or 2.9 +/- 1.0 mm respectively. Moreover, following inhibition by DIDS of all anion exchangers in HCO-3-free Ringer, the equilibrium potential for Cl- does not differ from the membrane potential V2. Finally, the logarithmic changes in aiCl in various experimental conditions correlate well with the simultaneous changes in either basolateral or apical membrane potential. These findings strongly support the presence of Cl- channels at the apical and basolateral cell membranes of the proximal tubule.  相似文献   
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