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91.
PURPOSE: This study investigated the pathogenesis of tractional retinal detachment associated with proliferative vitreoretinopathy in an experimental model, using immunohistochemical staining. METHODS: To produce tractional retinal detachment in rabbit eyes, homologous cultured fibroblasts obtained from the gluteal muscle fascia were injected intravitreously. Right eyes of 20 rabbits in the study group, and 7 rabbits in the control group were followed for 26 days at weekly intervals with indirect ophthalmoscopy and fundus photographs. RESULTS: During the follow-up period grade III tractional retinal detachment developed in 11 eyes, grade II in six, and grade 1 in three eyes. The spindle-shaped cells contributed predominantly to the development of epiretinal membrane, and a smaller number of round small and large cells. In 10/17 grade II and III eyes, spindle-shaped cells had vimentin, 7/10 had actin, 5/17 had GFAP, 4/17 had S-100 protein immunoreactivity. Round small and large cells expressed S-100 protein, GFAP and actin in 5/17 eyes. Epiretinal membrane appeared to be formed by spindle-shaped fibroblast-like cells and small and large round glia-like cells. Actin positivity of spindle-shaped and round cells was taken as a marker of contractile elements of the cells and their locomotional features. CONCLUSIONS: These features are believed to be involved in contraction of the membrane and retinal detachment.  相似文献   
92.
The degree and nature of patient involvement in consultations with health professionals influences problem and needs recognition and management, and public accountability. This paper suggests a framework for understanding the scope for patient involvement in such consultations. Patients are defined as co-producers of formal health services, whose potential for involvement in consultations depends on their personal rights, responsibilities and preferences. Patients' rights in consultations are poorly defined and, in the National Health Service (NHS), not legally enforceable. The responsibilities of patients are also undefined. I suggest that these are not to deny, of their own volition, the rights of others, which in consultations necessitate mutuality of involvement through information-exchange and shared decision-making. Preferences should be met insofar as they do not militate against responsibilities and rights.  相似文献   
93.
Depression is one of the most common reasons for using complementary and alternative therapies. The aim of this article is to provide an overview of the evidence available on the treatment of depression with complementary therapies. Systematic literature searches were performed using several databases, reference list searching, and inquiry to colleagues. Data extraction followed a predefined protocol. The amount of rigorous scientific data to support the efficacy of complementary therapies in the treatment of depression is extremely limited. The areas with the most evidence for beneficial effects are exercise, herbal therapy (Hypericum perforatum), and, to a lesser extent, acupuncture and relaxation therapies. There is a need for further research involving randomized controlled trials into the efficacy of complementary and alternative therapies in the treatment of depression.  相似文献   
94.
PURPOSE: To determine the role of SPARC (secreted protein, acidic, and rich in cysteine) in cataractogenesis by examining mice deficient in a matricellular protein SPARC. METHODS: Mice were rendered SPARC-deficient by a targeted disruption of the gene. Slit-lamp microscopy and histology were used to examine the eyes of SPARC-null and wild-type mice from birth to 14 months of age. RESULTS: SPARC-null mice developed opacities in the posterior cortex of the eye as early as 1.5 months after birth. The diffuse cataracts appeared to progress toward the anterior cortex and reached maturity in many animals by 3.5 months of age. Early stages of cataractogenesis in SPARC-null mice included inhibition of normal lens fiber cell differentiation, degeneration of fiber cells, vacuole formation at the equator, and liquefaction of the cortex. No cataracts were detected in wild-type mice up to the age of 8 months. CONCLUSIONS: The early onset of cataracts in SPARC-null mice establishes that the gene is essential to the maintenance of lens transparency.  相似文献   
95.
A new assay termed the dome disappearance method for classical swine fever virus (CSFV) using FS-L3 cells with serum-free culture medium was developed. The CSFV live vaccine GPE- strain grows well and shows a slight cytopathic effect (CPE) in FS-L3 cells. This CPE results in the disappearance of the unique fluid-filled multicellular domes on a single monolayer of FS-L3 cells. By using this phenomenon, dome disappearance, as a marker of infection, it was possible to determine the titers of CSFV and its neutralizing antibody. The virus titer determined by this method shows a good correlation with that determined by immunochemical and interference methods. Furthermore, the amount of neutralizing antibody measured by this method also correlated with that measured by the Exaltation of Newcastle Disease Virus (END) neutralizing method. The dome disappearance method developed in this experiment is a simple and safe procedure and has the great advantage that bovine serum, which may contain antibody against bovine viral diarrhea virus, is not necessary for the cultivation of FS-L3 cells.  相似文献   
96.
This article is based on research into patients' perceptions of being in hospital. Time, ordinarily taken for granted, becomes a significant problem for people in hospital. Patients seek control over time that they do not seem to have during their stay in hospital. They try to keep track of time and find ways of passing it, while believing that precious personal time is lost to them. The insight gained into differing perceptions of time and how patients coped with these can be used to reduce some of the tensions and negative aspects of the way time is experienced in hospital.  相似文献   
97.
Quinine and quinidine are reported to potentiate the behavioural effects of serotonergic agents and monoamine uptake inhibitors. We have therefore investigated the presynaptic actions of quinine and quinidine on monoamine uptake and release in rat brain tissue in vitro. Quinidine evoked the release of [3H]5-HT, [3H]noradrenaline and [3H]dopamine from pre-loaded rat brain slices in a concentration dependent manner with EC50 values of 175, 486 and 150 microM, respectively. Quinine induced [3H]monoamine release with similar potencies. Both quinine and quinidine also inhibited the active uptake of [3H]5-HT, [3H]noradrenaline and [3H]dopamine into rat brain synaptosomes with IC50 values in the range 0.13-12.4 microM. The potency of each drug to inhibit [3H]5-HT uptake was significantly higher than that for [3H]noradrenaline or [3H]dopamine. The relative potency of quinidine compared to quinine was more marked in the case of [3H]5-HT (58-fold) than for [3H]noradrenaline (3-fold) or [3H]dopamine (4-fold). The inhibition of [3H]5-HT uptake by quinine and quinidine was competitive in nature and corresponded with the potencies of these drugs to inhibit [3H]paroxetine binding. No correlation was observed between the potencies of quinine and quinidine to induce the release of [3H]monoamines and to inhibit their uptake, suggesting that these effects are mediated by two distinct mechanisms. We conclude that the presynaptic actions of quinine and quinidine on monoamine uptake and release may be implicated in their potentiation of the effects of serotonergic agents and uptake blockers.  相似文献   
98.
99.
This paper concerns the stability analysis problem of discrete linear systems with state saturation using a saturation-dependent Lyapunov functional.We introduce a free matrix characterized by the sum of the absolute value of each elements for each row less than 1,which makes the state with saturation constraint reside in a convex polyhedron.A saturation-dependent Lyapunov functional is then designed to obtain a sufficient condition for such systems to be globally asymptotically stable.Based on this stability criterion,the state feedback control law synthesis problem is also studied.The obtained results are formulated in terms of bilinear matrix inequalities that can be solved by the presented iterative linear matrix inequality algorithm.Two numerical examples are used to demonstrate the effectiveness of the proposed method.  相似文献   
100.
从人类运用艺术来表达感情和生活始,装饰与艺术便如影随形。波普艺术作为重要的艺术流派,其中的装饰语言值得人们探究。本文以波普艺术为切入点,重点从装饰图案的角度解析波普艺术中的装饰语言。结合产生的背景,分析波普艺术采用装饰图案的产生原因;再以色彩、形式等方面分析波普风格装饰图案的特征,寻求波普艺术视觉审美中的亮点,以期能对中国当代设计艺术有所启发与帮助。  相似文献   
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