首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   8篇
  免费   1篇
机械仪表   1篇
轻工业   1篇
无线电   1篇
一般工业技术   2篇
冶金工业   4篇
  2018年   1篇
  2017年   2篇
  2012年   1篇
  2006年   1篇
  1999年   1篇
  1998年   2篇
  1996年   1篇
排序方式: 共有9条查询结果,搜索用时 15 毫秒
1
1.
This study was undertaken to determine the usefulness of magnetic resonance imaging (MRI) in the diagnosis of flexor tendon rupture in patients who had prior surgery. Magnetic resonance imaging scans were performed on 11 digits (16 tendons) with the clinical diagnosis of flexor tendon rupture. Clinical suspicion correlated with MRI and surgical findings. Clinical examination yielded a 60% accuracy in diagnosis. MRI differentiated rupture from adhesions with a 100% accuracy rate. The MRI scan is a valuable tool in diagnosing tendon ruptures and may help reduce the incidence of unnecessary tendon explorations.  相似文献   
2.
This case report describes the use of a single lateral arm flap sequentially transferred to two defects in a bilateral hand injury. We believe this is a novel approach in reconstructing defects in bilateral hands when a staged reconstruction is planned.  相似文献   
3.
This paper investigates the role of variable lead time, learning in production and screening errors in a vendor–buyer supply chain with defective items. The vendor–buyer supply chain is modelled for supplying a single item considering that the lots from vendor may contain some defective items. It is assumed that demand during lead time follows a normal distribution. Moreover, the production time at vendor’s facility is assumed to follow learning whereas buyer’s screening for defective items is prone to errors as well. Numerical examples are presented to illustrate the impact of different variables in the model. The analysis shows that delay in transportation lead time forces the buyer to carry more inventories to avoid shortages. Further, Type I error has a major impact on this cost. It was found that learning in production keeps on reducing the total cost of the supply chain up to a threshold.  相似文献   
4.
We have recently reported that in vitro low dose of ultraviolet B radiation (UVB, 100-200 J per m2) directly impaired the antigen-presenting function of human Langerhans cells. In this study, we analyzed the effect of UVB irradiation on the Langerhans cells expression of several accessory molecules, namely CD54, CD80, and CD86. Langerhans cells phenotype was determined either immediately after UVB exposure (100 J per m2) or after a 2 d culture. No modification in cell surface antigen levels was observed immediately after irradiation. Prior UVB exposure did not modify the levels of CD80 at the Langerhans cells surface after a 2 d culture. In contrast, CD54 and, above all, CD86 expression were significantly decreased. Addition of exogenous anti-CD28 monoclonal antibodies partly restored the allostimulatory property of irradiated Langerhans cells in mixed epidermal cell-lymphocyte reaction, demonstrating that impairment of CD86 upregulation contributes to the UVB-induced immunosuppressive effect. Furthermore, we found that UVB irradiation at 200 J per m2 significantly reduced the number of viable Langerhans cells after 2 d of culture. UVB-induced cytotoxicity was due to apoptotic cell death, as demonstrated by typical morphologic alterations and by DNA fragmentation yielding a classical ladder pattern on gel electrophoresis. Interestingly, interaction of Langerhans cells with CD40-ligand transfected L cells improved the viability of irradiated Langerhans cells, counteracted the inhibition of CD86 expression, and efficiently reduced the number of apoptotic cells after a 2 d culture. Collectively, these results demonstrate that in vitro UVB exposure affects Langerhans cells via at least two distinct pathways: (i) decreased CD86 costimulatory molecule upregulation; and (ii) induction of Langerhans cells apoptosis, a phenomenon partly prevented by CD40 triggering.  相似文献   
5.
This paper considers the impact of forecasting methods on the bullwhip effect for a simple replenishment system in which a first-order autoregressive process describes the customer demand and an order-up-to inventory policy characterizes the replenishment decision. The impact of exponential smoothing and minimum mean squared error forecasting is measured for both the bullwhip effect and inventory variances. Previous similar studies have focused on investigating the impact of forecasting methods on bullwhip effect. However, little research has been carried out to explore the impact of forecasting methods for both bullwhip effect and inventory variances. Through simulation experiments, it has been found that depending on the structure of the demand process, the appropriate selection of forecasting technique can reduce, or even eliminate (i.e., “dewhip”) the bullwhip effect. However, in terms of inventory variances it has been shown that the inventory variances for the exponential smoothing are greater than the minimum mean squared error forecasting method and that gap increases as lead time increases. These findings will help companies to choose the appropriate forecasting technique depending on the nature of demand. These guidelines can help companies to reduce the bullwhip effect and inventory variances across supply chain.  相似文献   
6.
Bile salts containing vesicles (bilosomes) represent a portentous vesicular carrier that showed prosperous results in delivering active moieties in the gastrointestinal tract (GIT). In this study, bilosomes were exploited to deliver sulfated polysaccharide–protein complexes of Enteromorpha intestinalis (EHEM) and enhance its activity against hepatocellular carcinoma as well as resist harsh GIT conditions. Bilosomes were prepared using the sodium salt of three different bile acids (cholic, deoxycholic, taurodeoxycholic) and two different nonionic surfactants (Span 40 and 65). The effects of experimental variables were thoroughly studied to obtain an optimum formulation loading EHEM. The selected formulation (EH-Bilo-2) prepared with sodium cholate and Span 65 displayed nano-sized (181.1?±?16.80?nm) spherical vesicles with reasonable entrapment efficiency (71.60?±?0.25%) and controlled release properties; and thus was investigated as anti-hepatocarcinogenic candidate for in vivo studies. Treatment of hepatocellular carcinoma (HCC) bearing rats with EH-Bilo-2 experienced significant decrease in serum α-fetoprotein, endoglin, lipocalin-2, and heat shock protein 70 levels vs. the untreated counterparts. Furthermore, the photomicrographs of their liver tissue sections showed focal area of degenerated pleomorphic hepatocytes with fine fibrosis originating from the portal area. Thus, the optimized bilosomal formulation is a promising delegate for tackling hepatocellular carcinoma owing to its powerful anti-cancer and anti-angiogenic activity.  相似文献   
7.
8.
We consider zero-delay joint source-channel coding of individual source sequences for a general known channel. Given an arbitrary finite set of schemes with finite-memory (not necessarily time-invariant) decoders, a scheme is devised that does essentially as well as the best in the set on all individual source sequences. Using this scheme, we construct a universal zero-delay joint source-channel coding scheme that is guaranteed to achieve, asymptotically, the performance of the best zero-delay encoding-decoding scheme with a finite-state encoder and a Markov decoder, on all individual sequences. For the case where the channel is a discrete memoryless channel (DMC), we construct an implementable zero-delay joint source-channel coding scheme that is based on the "follow the perturbed leader" scheme of Gyoumlrgy for lossy source coding of individual sequences. Our scheme is guaranteed to attain asymptotically the performance of the best in the set of all encoding-decoding schemes with a "symbol-by-symbol" decoder (and arbitrary encoder), on all individual sequences  相似文献   
9.
Nitric oxide (NO) synthase (NOS)-containing cerebrocortical neurons degenerate in patients with amyotrophic lateral sclerosis (ALS) and dementia, and in transgenic mice expressing a mutated superoxide dismutase gene (G93A) associated with familial ALS. The cerebral cortex of transgenic mice displayed decreased NOS activity (p<0.001) and cGMP levels (p<0.01), but no changes in NOS content indicating that less NO is produced. Therefore, NOSN degeneration is not caused by elevated NO.  相似文献   
1
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号