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1.
A bulky, necrotic cervix with parametrial thickening often elicits an initial diagnostic impression of carcinoma of the cervix. A case is presented in which such a lesion proved to be tuberculosis of the cervix with combined genitourinary tuberculosis.  相似文献   
2.
Physical gaming is a genre of computer games that has recently been made available for the home. But what does it mean to bring games home that were originally designed for play in the arcade? This paper describes an empirical study that looks at physical gaming and how it finds its place in the home. We discuss the findings from this study by organizing them around four topics: the adoption of the game, its unique spatial needs, the tension between visibility and availability of the game, and what it means to play among what we describe as the gaming circle, or players and non-players alike. Finally, we discuss how physical gaming in the home surfaces questions and issues for householders and researchers around adoption, gender and both space and place.  相似文献   
3.
Tissue plasminogen activator (tPA) is a serine protease that has been shown to be involved in neuronal degeneration. Recently, elevated cerebellar tPA has been reported in a naturally occurring mutant mouse, weaver. Weaver mice suffer extensive degeneration of cerebellar granular neurons during development, leading to severe malformation of the cerebellum as well as abnormal behavior (ataxia). The observations that the developing weaver cerebellum displays a 10-fold increase in tPA activity over wild-type and that a serine protease inhibitor was able to rescue weaver granule cells from premature death in culture suggested that tPA might mediate the death of these mutant neurons. We tested this possibility by introducing the weaver mutation into tPA-deficient mice and comparing the weaver phenotype in the presence or absence of tPA. Analysis at 28 days after birth indicates that tPA-deficient weaver mice are indistinguishable from tPA-containing weaver mice in behavior, cerebellar anatomy, histology, and laminin expression (also reported to be increased in weaver). These results suggest that removal of tPA activity from weaver mice does not protect against neuronal degeneration in the cerebellum and, thus, tPA does not appear to mediate this form of cell death.  相似文献   
4.
1. The adaptational changes induced after chronic desipramine treatment on functional responsiveness of alpha 2-adrenoceptor activation were investigated in prostatic portions of the rat vas deferens. 2. For this purpose, clonidine and xylazine were studied for their effects on twitch contractions elicited by electrical field stimulation of prostatic portions removed 48 h after the last injection to the animals of vehicle or desipramine (10 mg kg-1, i.p.; 14 days). Operational model-fitting and the nested hyperbolic method were used to analyse the effects of irreversible receptor alkylation by N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ, 300 nM) on the alpha 2-adrenoceptor-mediated effects of clonidine, either in vehicle- or in desipramine-treated animals. 3. Treatment with desipramine decreased the potency (increased the EC50) of clonidine and xylazine by about 12 and 9 fold respectively. However, the treatment did not modify the maximal effect (alpha) elicited by either agonist. The estimates of apparent affinity for clonidine did not depend on the method of calculation as the 'null' method and the 'operational' method gave similar answers. Estimates of tau values for both agonists revealed that chronic desipramine treatment resulted in significant decreases in the efficacy of agonists. However, desipramine treatment was not associated with significant changes in the affinity constant for clonidine while for xylazine, the operational model provided a higher estimate of KA (lower affinity) after desipramine treatment. 4. The results indicate a large receptor reserve at prejunctional alpha 2-adrenoceptors which is modulated by chronic desipramine treatment. 5. The comparison of results obtained after chronic desipramine exposure with those by using EEDQ suggests that chronic desipramine treatment is not a useful experimental intervention for the purpose of estimating agonist affinities and efficacies.  相似文献   
5.
Rejoinder     
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6.
This is an innovative study of wood wool used for building insulation and the reported results could be important for improving the cooling and the heating efficiency of buildings. Wood fibre boards are non-grey, absorbing and scattering media. The radiative properties of the wood wool (albedo, optical thickness and phase function coefficients) were identified using an inverse method based on infrared experimental measurements of reflection and transmission. The radiative part was then found negligible with respect to the phonic part in steady state for the material tested. Transient one-dimensional coupled radiative and conductive heat transfer was solved in a wood wool material. The transient numerical results were validated by comparing them with fluxmeter measurements when temperatures were fixed at the boundaries. The temperatures and the heat capacity had strong influence on the transient numerical results. Finally, our computations showed that a purely conductive model gives the same fluxes at the boundary as the coupled radiative-conductive model.  相似文献   
7.
This paper presents a new method to design pressurized branched irrigation networks. This method is called recursive design and is based on application of the problem-solving technique known as backtracking to the problem of the optimum design of pressurized branched irrigation networks with a known delivery piezometric head (pipe-sizing). Recursive design is a heuristic optimizer, like genetic algorithms, and has been implemented in a fast, versatile computer application. After presenting and precisely defining the design problem, the writers review the theoretical foundations of some of the main existing design methods: maximum velocity, recommended velocity, Mougnie velocity, constant hydraulic slope, Lagrange multipliers, linear programming, Labye’s method, and genetic algorithms. Next, the writers explain what recursive design consists of and apply its methodology in detail to a simple network. In the results section, the solutions obtained by recursive design are compared with those obtained by the other design methods, giving satisfactory results. For example, in an analyzed standard network, genetic algorithms take more than 20?minutes to offer a solution, whereas recursive design offers a cheaper solution with less than 3?seconds of computation time.  相似文献   
8.
The authors report the results of a six months survey about the low weight of birth (L.W.B.) in the district of Guédiawaye, suburb of Dakar. The purpose is to determine the rate of L.W.B. in two main maternity hospitals of that locality and the associated risk factors. It is a survey with a control group. This survey results in a 10.7% rate, according to the data of another retrospective survey in the same maternity hospitals in 1992 (10.03%). The risk factors are mainly: celibacy, primiparity, an associated pathology with the pregnancy, the physical strain of mothers correlated to the income and to the previous L.W.B.  相似文献   
9.
Physically loading aspects of work may have adverse effects on the health of both the pregnant woman and the unborn child. Improving the fit between the pregnant woman and the workplace layout contributes to minimizing the load associated with given tasks. The aim of this paper is to evaluate two layout aspects for standing manual work, namely working surface height and working surface areas, for the condition of pregnancy. Two approaches were used. (1) The effects of changed body dimensions were evaluated with regard to (a) fit problems while working at a workplace in accordance with common guidelines and (b) the validity of assumptions of these guidelines. (2) The appreciation of relevant aspects of workplace layout at a specific manual task was assessed. Twenty-seven women were examined in pregnant and non-pregnant conditions. The first approach showed that fit problems are likely: guideline working surface height is just (2-7 cm) under the most protruding abdominal point, and areas based on non-pregnant abdominal depth are relatively large in pregnant condition. Further, existing methods to assess working surface areas have various assumptions that are not valid in pregnant condition. The second approach showed that at a specific manual task, women in late pregnancy preferred a considerably lower table height than the common guideline heights. Possibly, abdominal height becomes a relevant design factor with regard to working surface height during pregnancy. The task position on the working surface at which effort started became closer to the table edge due to pregnancy. Both approaches show that common guideline working surface heights for manual work, and working surface areas assessed in non-pregnant condition seem not suitable in pregnant condition.  相似文献   
10.
Herein, we report on tin monosulfide (SnS) thin films elaborated by the Chemical Spray Pyrolysis (CSP) technique onto various substrates as simple glass, ITO-, and Mo-coated glasses in order to study the influence of substrates on the physical and chemical properties of Sns thin films. Structural analysis revealed that all films crystallize in orthorhombic structure with (111) as the sole preferential direction without secondary phases. In addition, film prepared onto pure glass exhibits a better crystallization compared to films deposited onto coated glass substrates. Raman spectroscopy analysis confirms the results obtained by X-ray diffraction with modes corresponding well to SnS single-crystal orthorhombic ones (47, 65, 94, 160, 186, and 219 cm ?1) without any additional parasite secondary phase like Sn2S3 or SnS2. Field emission scanning electron microscope revealed that all films have a cornflake-like particles surface morphology, and energy dispersive X-ray spectroscopy analysis showed the presence of sulfur and tin with a nearly stoichiometric ratio in films deposited onto pure glass. High surface roughness and large grains are observable in film deposited onto glass. From optical spectroscopy, it is inferred that band gap energy of SnS/glass and SnS/ITO were 1.64 and 1.82 eV, respectively.  相似文献   
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