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1.
OBJECTIVE: Our objective was to determine the interest of laparoscopic assisted vaginal hysterectomy. STUDY DESIGN: Between January 1991 to december 1994, 80 patients had laparoscopically assisted vaginal hysterectomy. We reviewed with particular emphasis characteristic indications, complications. RESULTS: Eighty were performed as laparoscopically assisted vaginal hysterectomy. 14 patients (17.5%) had laparotomy conversion; because of size of uterus in 3 cases, suspected ovarian tumor in 3 cases. Pelvic adherences in 4 cases, urinary tract injuries in 1 case, hypercapnia in 1 case, hemorrhage in 2 cases. 9 patients experienced febrile morbidity and 1 urinary infection. 1 patient received 2 units of packed red blood cells. The hospital stay was 5 days for laparoscopically assisted vaginal hysterectomy versus 5.9 for laparotomic hysterectomy. CONCLUSION: Laparoscopically assisted vaginal hysterectomy offers a technique to convert certain abdominal hysterectomies into vaginal hysterectomies with a 17.5% laparoconversion rate.  相似文献   
2.
Investigations into probiotics have focused on their health benefits thus far, with some of the findings finally reaching the food and pharmaceutical industries, which have used them for commercial purposes. In biocontrol research some microbes, mainly isolated from plants, have shown antagonism towards both enteric and plant pathogens, and some of them represent probiotic species. Fresh fruits and vegetables are regarded as health‐promoting dietary constituents, and if probiotics could be used to control the pathogens on them then they could turn out to be even healthier. The fresh produce industry still depends on agrochemicals and the increase in the demand for high‐priced organically grown produce indicates consumer concerns regarding the use of agrochemicals. If the potential of probiotic organisms to serve as biocontrol agents for fresh produce is exploited, all fresh produce can be made as safe as organically grown produce, and much more wholesome. This review appraises the feasibility of such a move by evaluating how research has progressed in both disciplines (probiotic and biocontrol) and suggests sharing results from research via information technology, efficient collaboration, and the use of novel molecular biological tools to achieve the objective of probiotic antagonists. © 2018 Society of Chemical Industry  相似文献   
3.
The Grüneisen parameter (γ) is of considerable importance to Earth scientists because it sets limitations on the thermo elastic properties of the lower mantle and core. However, there are several formulations of the Grüneisen parameter in frequent use which not only give different values for Grüneisen parameter at ambient pressure but also predict a varying dependence of Grüneisen parameter as a function of compression. The Grüneisen parameter is directly related to the equation of state (EOS), yet it is often the case that both the form of and the EOS are chosen independently of each other and somewhat arbitrarily. In this paper we have assessed some of the more common definitions of the Grüneisen parameter and the EOS's, and have applied them to test the validity of EOS for six different bulk metallic glasses.  相似文献   
4.
the steady state behaviour of non-circular worn journal bearings is analysed for various wear depth parameters (δ0), following Constantinescu's turbulent lubrication theory. Computed results are compared with published results. It is observed that geometric change caused by wear has a significant effect on the steady state characteristics of bearings.  相似文献   
5.
Gel time and Brookfield viscosity studies of epoxy resins containing varying concentrations of cellulose, periodate oxidized cellulose, chromic acid oxidized cellulose, and ethylene glycol were carried out at 120°C using the tertiary amine hexamethylene tetramine as catalyst. It was found that the hydroxyl groups of cellulose and oxidized cellulose did not only act as accelerators for the tertiary amine catalyzed polymerization of the epoxy resin, but evidence was also found which pointed to the actual participation of the cellulosic fillers in the crosslinking reaction leading to the thermoset epoxy polymer. The gel times of the epoxy curing reaction decreased as the concentrations of the cellulosic fillers increased. The change in viscosity with time (curing characteristics) curves for 40 parts of cellulose or oxidized cellulose per hundred parts of resin (phr) were similar to that of 10 phr ethylene glycol, while the curve for 20 phr cellulose-filled epoxy resin was almost identical to the curve for 10 phr periodatefilled resin. These differences are explained on the basis of the percentage of hydroxyl groups in the various filler molecules that are available for their role as accelerators. The possibility of greater participation of oxidized cellulose in the network formation with the epoxy resin than ordinary cellulose has also been surmised on the basis of its increased viscosity build-up after the gel time is achieved.  相似文献   
6.
A five-axis machine is presently one of the most versatile machine tools available and they are becoming increasingly common. To increase the accuracy capabilities of such machines, it is crucial to be able to study the geometric errors of the components and its effect on the quality of machined products. In five-axis machine tools, all linear axes are theoretically perpendicular (dot product, cos 90°=0) to each other and directed along or around the X, Y and Z of the cartesian coordinate system; but in working machines, the axes are nearly perpendicular (cos89.90°≠0) because of manufacturing error and assembly error or quasi-static error. The present paper discusses the development of a generalised error model for the effects of geometric errors of the components of the kinematic chain of a machine in the workspace and the results obtained by this model have been verified experimentally. The effect of geometric error has been studied further for cam profile generation using a five-axis machining centre and an improvement in the profile has been obtained.  相似文献   
7.
The ectopic pregnancy (EP) could be treated by spontaneous resolution, or medical treatment or laparoscopic treatment. Spontaneous resolution of EP with beta hCG < 1,000 mUl/ml, plasmatic progesterone < 5 ng/ml had 74% success rate. Methotrexate (MTX) injection is the common Medical treatment of EP with beta hCG < or = 5,000 mUl/ml and mean diameter of EP < or = 3 cm: a single dose of 50 mg/m2 or 1 mg/kg intramuscular injection had 93.4% success rate; local injection under sonographic control (1 mg/kg) had 80.2% success rate. The surgical conservative treatment by laparoscopy had 94% success rate.  相似文献   
8.
Intervertebral disc (IVD) degeneration can cause chronic lower back pain (LBP), leading to disability. Despite significant advances in the treatment of discogenic LBP, the limitations of current treatments have sparked interest in biological approaches, including growth factor and stem cell injection, as new treatment options for patients with chronic LBP due to IVD degeneration (IVDD). Gene therapy represents exciting new possibilities for IVDD treatment, but treatment is still in its infancy. Literature searches were conducted using PubMed and Google Scholar to provide an overview of the principles and current state of gene therapy for IVDD. Gene transfer to degenerated disc cells in vitro and in animal models is reviewed. In addition, this review describes the use of gene silencing by RNA interference (RNAi) and gene editing by the clustered regularly interspaced short palindromic repeats (CRISPR) system, as well as the mammalian target of rapamycin (mTOR) signaling in vitro and in animal models. Significant technological advances in recent years have opened the door to a new generation of intradiscal gene therapy for the treatment of chronic discogenic LBP.  相似文献   
9.
The production of lysine by fermentation was studied, using a homoserine-deficient and aminoethylcysteine-resistant strain of Corynebacterium glutamicum, in 1-dm3 shake flasks and a 14-dm3 laboratory fermentor. Molasses was used as substrate. Superphosphate-treated black strap molasses gave better lysine production. Lysine production, residual sugar and dry cell mass were measured as a function of fermentation time. It was observed that 1 g of cell mass produced 3.36 g of lysine.  相似文献   
10.
Suspicious mass traffic constantly evolves, making network behaviour tracing and structure more complex. Neural networks yield promising results by considering a sufficient number of processing elements with strong interconnections between them. They offer efficient computational Hopfield neural networks models and optimization constraints used by undergoing a good amount of parallelism to yield optimal results. Artificial neural network (ANN) offers optimal solutions in classifying and clustering the various reels of data, and the results obtained purely depend on identifying a problem. In this research work, the design of optimized applications is presented in an organized manner. In addition, this research work examines theoretical approaches to achieving optimized results using ANN. It mainly focuses on designing rules. The optimizing design approach of neural networks analyzes the internal process of the neural networks. Practices in developing the network are based on the interconnections among the hidden nodes and their learning parameters. The methodology is proven best for nonlinear resource allocation problems with a suitable design and complex issues. The ANN proposed here considers more or less 46k nodes hidden inside 49 million connections employed on full-fledged parallel processors. The proposed ANN offered optimal results in real-world application problems, and the results were obtained using MATLAB.  相似文献   
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