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31.
BACKGROUND: The emergence of psychogenic seizures after surgery for epilepsy is not well recognized. OBJECTIVES: To identify the frequency of psychogenic seizures in an 11-year surgical experience and to characterize the patients with this complication. METHODS: Ninety-six patients underwent surgery for epilepsy between 1985 and 1996. The surgical database was reviewed and all patients who experienced postoperative psychogenic seizures were identified. Patients were characterized by sex, age, psychopathologic conditions, full-scale IQ, duration of epilepsy, surgical procedure, and operative complications. Patients were compared with the surgical group as a whole for these variables. SETTING: A comprehensive epilepsy center. RESULTS: Five patients were identified: 3 men and 2 women. Mean full-scale IQ was 73 (range, 66-82). Mean age was 29.8 years (range, 22-36 years). Three patients were diagnosed as having psychosis, 1 with borderline personality disorder and 1 with generalized anxiety. Operations included 4 anterior temporal lobectomies and 1 occipital lobectomy. Two patients experienced operative complications. Compared with the surgical cohort, patients had a higher frequency of preoperative psychopathologic conditions, lower mean full-scale IQ, and a greater occurrence of operative complications. CONCLUSIONS: (1) Patients can develop new-onset psychogenic seizures after surgery for epilepsy. (2) Low full-scale IQ, serious preoperative psychopathologic conditions, and major surgical complications may be risk factors. (3) Atypical postoperative seizures should be evaluated with video electroencephalographic monitoring before concluding that they are epileptic.  相似文献   
32.
Androgens repress expression of many genes, yet the mechanism of this activity has remained elusive. The cytokine, interleukin-6, is active in a variety of biological systems, and its expression is repressed by androgens. Accordingly we dissected the mechanism of androgen's ability to inhibit interleukin-6 expression at the molecular level. In a series of co-transfection assays, we found that 5alpha-dihydrotestosterone, through the androgen receptor, repressed activation of the interleukin-6 promoter, in part, by inhibiting NFkappaB activity. It did not appear that 5alpha-dihydrotestosterone inhibited NFkappaB by activating the androgen receptor to compete for the NFkappaB response element as we could not detect androgen receptor binding to the IL-6 promoter by DNase I footprinting assay. However, by electrophoretic mobility shift assay we found that 5alpha-dihydrotestosterone repressed formation of NFkappaB middle dotNFkappaB response element complex formation. In LNCaP prostate carcinoma cells, 5alpha-dihydrotestosterone achieved this effect through maintenance of IkappaBalpha protein levels in the face of phorbol ester, a stimulus that results in IkappaBalpha degradation. Finally, we confirmed that IkappaBalpha inhibits NFkappaB-mediated activation of the interleukin-6 promoter. These data suggest that maintenance of IkappaBalpha levels may represent the first identified mechanism for androgen-mediated repression of a natural androgen-regulated gene.  相似文献   
33.
BACKGROUND AND PURPOSE: Norway has the highest reported incidence of hip fractures in western Europe. Little is known about the epidemiology of falls in Norway where the winter season is long and dark. The objective of this work was to study reported falls and their consequences among elderly Norwegians living at home. METHODS: A cross-sectional design was used for the study. Interviews were performed in the homes of 431 subjects, aged 67-97 years, living at home. Information on falling was gathered through six questions: whether the subject had fallen during the last six months, and if so, how many falls they had, where the last fall occurred, its perceived reason, the activity the subject had been engaged in when the fall occurred, and the resulting injury. RESULTS: In all, 24.1% of subjects reported falling during the last six months, and 9.5% had suffered more than one fall. Falls were most frequently linked to external events (63.1%). Outdoor falls were more frequent (59.0%; 95% CI = 51.2-82.0) than indoor falls. Older subjects were associated with more frequent indoor falls (p < 0.05), but gender was not significant. Fifty-one per cent of subjects had fallen while walking and 53% had suffered an injury from the last fall. In 13.4% of the women and 16.2% of the men, the last fall had resulted in a fracture. CONCLUSIONS: Compared to the results of other studies from industrialized Western countries, a similar crude fall rate, similar frequency and similar type of injury were found. However, in contrast to other studies, no gender difference was observed with regard to falling, place of falling and fracture rate.  相似文献   
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35.
This article aims to link the mainstream subject of chain-folded polymer crystallization with the rather speciality field of extended-chain crystallization, the latter typified by the crystallization of polyethylene (PE) under pressure. Issues of wider generality are also raised for crystal growth, and beyond for phase transformations. The underlying new experimental material comprises the prominent role of metastable phases, specifically the mobile hexagonal phase in polyethylene which can arise in preference to the orthorhombic phase in the phase regime where the latter is the stable regime, and the recognition of thickening growth as a primary growth process, as opposed to the traditionally considered secondary process of thickening. The scheme relies on considerations of crystal size as a thermodynamic variable, namely on melting-point depression, which is, in general, different for different polymorphs. It is shown that under specifiable conditions phase stabilities can invert with size; that is a phase which is metastable for infinite size can become the stable phase when the crystal is sufficiently small. As applied to crystal growth, it follows that a crystal can appear and grow in a phase that is different from that in its state of ultimate stability, maintaining this in a metastable form when it may or may not transform into the ultimate stable state in the course of growth according to circumstances. For polymers this intermediate initial state is one with high-chain mobility capable of thickening growth which in turn ceases (or slows down) upon transformation, when and if such occurs, thus locking in a finite lamellar thickness. The complete situation can be represented by a P, T, 1/l (l crystal thickness) phase-stability diagram which, coupled with kinetic considerations, embodies all recognized modes of crystallization including chain-folded and extended-chain type ones. The task that remains is to assess which applies under given conditions of P and T. A numerical assessment of the most widely explored case of crystallization of PE under atmospheric pressure indicates that there is a strong likelihood (critically dependent on the choice of input parameters) that crystallization may proceed via a metastable, mobile, hexagonal phase, which is transiently stable at the smallest size where the crystal first appears, with potentially profound consequences for the current picture of such crystallization. Crystallization of PE from solution, however, would, by such computations, proceed directly into the final stage of stability, upholding the validity of the existing treatments of chain-folded crystallization. The above treatment, in its wider applicability, provides a previously unsuspected thermodynamic foundation of Ostwald's rule of stages by stating that phase transformation will always start with the phase (polymorph) which is stable down to the smallest size, irrespective of whether this is stable or metastable when fully grown. In the case where the phase transformation is nucleation controlled, a ready connection between the kinetic and thermodynamic considerations presents itself, including previously invoked kinetic explanations of the stage rule. To justify the statement that the crystal size can control the transformation between two polymorphs, a recent result on 1 -4-poly-trans-butadiene is invoked. Furthermore, phase-stability conditions for wedge-shaped geometries are considered, as raised by current experimental material on PE. It is found that inversion of phase stabilities (as compared to the conditions pertaining for parallel-sided systems) can arise, with consequences for our scheme of polymer crystallization and with wider implications for phase transformations in tapering spaces in general. In addition, in two of the Appendices two themes of overall generality (arising from present considerations for polymers) are developed analytically; namely, the competition of nucleation-controlled phase growth of polymorphs as a function of input parameters, and the effect of phase size on the triple point in phase diagrams. The latter case leads, inter alia to the recognition of previously unsuspected singularities, with consequences which are yet to be assessed.  相似文献   
36.
Single crystals of poly(hydroxybutyrate), and copolymers of hydroxybutyrate and hydroxyvalerate, have been grown from a variety of solvents and their morphology studied. In all cases the crystals appear elongated, with the crystallographic a axis along the long axis of the crystals. Screw dislocations (which act as branch points and can lead to large crystal aggregates) have been observed, and solvents, e.g. octanol in which more of these dislocations occur, have been identified. Decoration of the crystals with polyethylene shows that the fold plane is the (0 1 0) plane, while crystallographic and crystallinity arguments require successive adjacent folds to be along 1 1 0 directions. It is argued that folding is along [1 1 0] on the top, and [1 ¯1 0] on the bottom surface of a crystal.  相似文献   
37.
In July 1996, Tennessee initiated a managed mental health and substance abuse program called TennCare Partners. This publicly funded "carve-out" experiment started chaotically and soon deteriorated into a crisis. Many patients did not receive care or lost continuity of care, and the traditional "safety net" mental health system nearly disintegrated. This qualitative case study sought to ascertain the impact of the TennCare Partners program. It points out that the program's difficulties stemmed directly from a flawed design that spread funds previously earmarked for severely mentally ill patients across the entire Medicaid population. States contemplating similar reforms should strive to protect vulnerable patients by risk-adjusting capitation payments and by focusing resources on care for severely mentally ill persons. States should also minimize program complexity and ensure the accountability of managed care networks for their patients' behavioral health care needs.  相似文献   
38.
To investigate possible biochemical mechanisms underlying the "toxic gain of function" associated with polyglutamine expansions, the ability of guinea pig liver tissue transglutaminase to catalyze covalent attachments of various polyamines to polyglutamine peptides was examined. Of the polyamines tested, spermine is the most active substrate, followed by spermidine and putrescine. Formation of covalent cross links between polyglutamine peptides and polyamines yields high-M(r) aggregates--a process that is favored with longer polyglutamines. In the presence of tissue transglutaminase, purified glyceraldehyde-3-phosphate dehydrogenase (a key glycolytic enzyme that binds tightly to the polyglutamine domains of both huntingtin and dentatorubral-pallidoluysian atrophy proteins) is covalently attached to polyglutamine peptides in vitro, resulting in the formation of high-M(r) aggregates. In addition, endogenous glyceraldehyde-3-phosphate dehydrogenase of a Balb-c 3T3 fibroblast cell line overexpressing human tissue transglutaminase forms cross-links with a Q60 polypeptide added to the cell homogenate. Possibly, expansion of polyglutamine domains (thus far known to occur in the gene products associated with at least seven neurodegenerative diseases) leads to increased/aberrant tissue transglutaminase-catalyzed cross-linking reactions with both polyamines and susceptible proteins, such as glyceraldehyde-3-phosphate dehydrogenase. Formation of cross-linked heteropolymers may lead to deposition of high-M(r) protein aggregates, thereby contributing to cell death.  相似文献   
39.
OBJECTIVES: An understanding of the validity and usefulness of self-reported measures (as distinct from clinically determined measures) of oral health is emerging. These self-reported measures include self-rated oral health (SROH). Three objectives were to: (1) describe self-rated oral health in dentate adults, (2) quantify associations between self-rated oral health and other measures of oral health (oral disease and tissue damage, pain and discomfort, functional limitation, and disadvantage), and (3) assess the construct validity of a model of oral health proposed herein. METHODS: The Florida Dental Care Study is a longitudinal study of oral health, which included at baseline 873 subjects who had at least one tooth, were 45 years or older, and who participated for an interview and clinical examination. RESULTS: The prevalence of self-rated oral health decrements was substantial; approximately one fourth of subjects reported their oral health as only fair or poor. Bivariate and multivariate results provided consistent evidence of the construct validity of the proposed model of oral health. Additionally, the salience of one measure of dental appearance suggests that persons may use esthetic cues when rating their oral health. CONCLUSIONS: The proposed multidimensional model of oral health has construct validity. Self-rated oral health is affected by oral disease and tissue damage, oral pain and discomfort, oral functional limitation, and oral disadvantage. These self-reported measures and the proposed model should provide useful information for dental care effectiveness research. General health status has been disaggregated into the "physical" and the "mental;" an additional separation into the "oral" aspects of health seems warranted.  相似文献   
40.
The hormone-binding domain of the glucocorticoid receptor must be bound to heat shock protein (hsp) 90 for it to have a high-affinity steroid-binding conformation. Cell-free assembly of a glucocorticoid receptor-hsp90 heterocomplex is brought about in reticulocyte lysate by a preformed protein-folding complex containing hsp90, hsp70, and other proteins [Hutchison, K.A., Dittmar, K. D., & Pratt, W.B. (1994) J. Biol. Chem. 269, 27894-27899]. In this "foldosome" system, hsp70 is required for assembly of the receptor-hsp90 complex and concomitant activation of steroid-binding activity [Hutchison, K.A., Dittmar, K.D., Czar, M.J., & Pratt, W.B. (1994) J. Biol. Chem. 269, 22157-22161]. All previous experiments involving cell-free assembly of both receptor-hsp90 and protein kinase-hsp90 heterocomplexes have been carried out with the protein-folding system in rabbit reticulocyte lysate. In this work, we show that concentrated lysates of receptor-free mouse (L cells) and insect (Sf9) cells and also a plant (wheat germ) lysate fold the immunopurified glucocorticoid receptor into a functional (i.e., steroid binding) heterocomplex with hsp90. Receptor heterocomplex formation in animal lysates and in the plant lysate are not identical in that the dynamics of complex assembly are different, but both systems produce a functional complex that binds steroid. Also, in contrast to animal and insect complexes, receptor-plant hsp90 complexes are not stabilized by molybdate. When added to the other lysate, purified plant and animal hsp90s show partial complementarity, in that a receptor-hsp90 complex is formed but the receptor is not converted to the steroid-binding conformation. When added to rabbit reticulocyte lysate that has been depleted of endogenous hsp70, purified wheat germ and mouse hsp70's are equally active in promoting both assembly of receptor-hsp90 heterocomplexes and conversion of receptor to the steroid-binding conformation. Thus, hsp70 from the plant kingdom has conserved the ability to interact functionally with chaperone proteins of the animal kingdom to cooperate in protein folding as evidenced by formation of a functional receptor-hsp90 heterocomplex.  相似文献   
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