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91.
PURPOSE: To evaluate whether the position of the central retinal vessel trunk exit on the lamina cribrosa spatially correlates with the location of parapapillary atrophy in glaucoma. METHODS: Color stereo optic disc photographs of 79 patients with primary or secondary open-angle glaucoma and 53 normal subjects were morphometrically evaluated. We determined the position of the central retinal vessel trunk exit on the lamina cribrosa surface and measured the area of parapapillary atrophy in four 90 degrees quadrants. RESULTS: After correction for normal values, the beta zone area of parapapillary atrophy in the glaucoma eyes was significantly larger, when measured in the disc quadrant most distant to the central retinal vessel trunk exit than as if measured in the quadrant containing the vessel trunk exit. CONCLUSIONS: Position of the central retinal vessel trunk exit on the lamina cribrosa influences the location of parapapillary atrophy in glaucoma. The longer the distance to the central retinal vessel trunk exit, the more enlarged is parapapillary atrophy.  相似文献   
92.
AIM: To evaluate prospectively in an experimental model of chronic high pressure glaucoma whether the concept of a mainly diffuse pattern of optic nerve damage holds true for high pressure glaucoma. METHODS: The study comprised nine eyes of nine rhesus monkeys (Macaca mulatta) with a mean age of 17.7 (SD 3.1) years (range 13-23 years). Experimental glaucoma was produced by multiple applications of argon laser to the trabecular meshwork. Applanation tonometry was regularly performed and fundus photographs, which were taken serially, were used for retinal nerve fibre layer (RNFL) assessment and morphometric optic disc analysis. Six monkeys, in which arterial hypertension and atherosclerosis had additionally been induced several years before elevation of intraocular pressure, did not show any sign of diffuse loss or localised defects of the RNFL before initiation of glaucoma. RESULTS: Compared with the same eyes at baseline, localised RNFL defects had developed in eight (89%) eyes. It included all three eyes (100%) of the monkeys without arterial hypertension/arteriosclerosis, and five of the six monkeys (83%) with arterial hypertension/arteriosclerosis. Four eyes had multiple localised RNFL defects. In all eyes, diffuse RNFL loss was additionally present. CONCLUSIONS: Besides diffuse loss of RNFL, localised RNFL defects were present in almost all eyes of monkeys with chronic experimental high pressure glaucoma. Challenging the concept that a mostly diffuse type of optic neuropathy occurs in high pressure glaucoma, the results suggest that, in high pressure glaucoma, at least a mixture of localised and diffuse pattern of optic nerve damage prevails.  相似文献   
93.
We describe the postnatal development of the electroretinogram (ERG) receptoral response in the guinea pig. In addition, the time course and nature of maturation was compared between albino and pigmented strains to consider the role that melanogenesis might have in this process. Electroretinograms were collected on groups of albino and pigmented animals from postnatal day (PD) PD1 to PD60. A-wave amplitudes and implicit times were extracted from filtered data (0–75 Hz). Receptoral components were modelled using the delayed gaussian model of Hood and Birch [1] fitted as an ensemble to the raw data. Guinea pigs show saturated amplitudes (RmP3) that are 50% of adult values at birth, these mature by PD12. Receptoral delay (td) also undergoes some postnatal maturation, while phototransduction gain (log S) is adult-like at birth. Albino animals had significantly (p<0.05) larger RmP3 and log S across all ages. Guinea pigs have significant postnatal development in their receptoral response. Maturation of RmP3 implies a postnatal increase in rod outer segment length. Whereas the adult values of log S implies a mature phototransduction process at birth. We argue that the likely cause for the larger log S of albino eyes is compatible with theories of increased levels of internal light. Whereas the larger RmP3, even after allowing for increased light effectiveness, may reflect a lower ocular resistance in albino eyes due to their lower levels of melanin. Furthermore, decreased RmP3 and log S with age is observed in the pigmented group only and is consistent with increased ocular resistance due to melanin development in this strain. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
94.
In the present study we investigated a panel of human breast cancer cell lines which were sensitive or resistant to the cytotoxic drug doxorubicin, for their abilities to synthesize and bind hyaluronan. We found that MDA-231 and HS-578T cells which express very low amounts of estrogen and progesterone receptors, both synthesized hyaluronan and expressed hyaluronan binding sites on the cell surface as did their doxorubicin-adapted counterparts MDA-231 Dox and HS-578T Dox. The binding was highly specific with a K-d of 0.48x10(-9) M. Most of the hyaluronan binding activity was blocked by mAbs against Hermes-l antigen indicating that the adhesion molecule CD44 is responsible for hyaluronan binding. Only 0.5% of the total amount of labeled hyaluronan added to the cultures was degraded during a period of 16 h. The hormone positive receptor cell lines, MCF-5, Zr-5-1 and Zr-5-1 Dox synthesized only minute amounts of hyaluronan and did not bind hyaluronan or express CD44 receptors. Expression of CD44-related hyaluronan receptors and synthesized hyaluronan may endow hormone receptor negative cells with a highly hydrated environment that facilitates cell motility and invasiveness. The lack of CD44 and thereby the lack of ability to bind hyaluronan in the extracellular matrix may contribute to the non-invasive behavior of hormone positive cell lines.  相似文献   
95.
The purpose of this study was to compare Doppler color flow mapping with angiography and surgical observation for detection of multiple ventricular septal defects (VSDs). Only patients with elevated pulmonary ventricular pressure were included. Among 137 patients with VSDs, 38 multiple defects were identified in 25 patients echocardiographically, 34 multiple defects in 24 patients angiographically, and 21 multiple defects in 17 patients surgically. Using surgical observation as the reference standard, the sensitivity of echocardiography for identifying patients with multiple VSDs was 17 of 17 (100%) and for angiography 15 of 17 (88%). The sensitivity of echocardiography for identifying all multiple VSDs seen at operation was 19 of 21 (90%) and of angiography was also 19 of 21 (90%). In many patients, use of both techniques may no longer be necessary.  相似文献   
96.
A lumped compartmental model has been derived to predict methotrexate concentration as a function of time for L1210 cells in BD2F 1 female mice at doses ranging from 3 mg/kg to 400 mg/kg. Using standard methods of parameter estimation as well as experimental determinations, an integrated approach was derived to account for the differences between the subcutaneous (s.c.) and intraperitoneal (i.p.) modes of injection. It was found that a single generalized forcing function can be used to fit plasma concentration after s.c. injection for all doses. Adequate fits (average error<20% while the standard deviation of experimental determinations was±22%) of L1210 cell data after s.c. injection were obtained. The best results were for a maximum facilitated influx constant Vmax of 0.424 g/min/ml, a Michaelis influx constant Km of 1,42 g/ml, and a first-order efflux constant of 0.047 min–1.The model simulations were not sensitive to Vmax, Km,and so long as the ratio Vmax/was approximately 9g/ml. The values of V max ,K m ,and which were obtained from our analysis of the in vivodata can be explained on the basis of previously performed in vitroexperiments. The parameters obtained from modeling the s.c. data were then applied for i.p. injection data. The resulting fits were adequate (average error<20% while the standard deviation of experimental determinations was±22%). A single generalized forcing function for drug concentration in the peritoneal cavity after i.p. injection for all doses was derived. The application of these results enables the prediction of methotrexate concentration in neoplastic cells at other doses after either s.c. or i.p. injection.  相似文献   
97.
After studying the historical importance of the domestic animal through the ages and the role of the "pet" animal in the contemporary world, the authors present an analysis of the literature dealing with the function of the animal in child development and the use of animals as therapeutic "tools". The author's then consider, based on a series of observations, the relationship certain mentally ill patients may establish with one or several pet animals and the significance this object relation may have for the patient : animals become invested as counter depressive or delusional objects, auxiliary means for identification and projection, symbiotic relationship, as well as encouraging feeling of security and responsibility.  相似文献   
98.
Summary The distribution of cytarabine in the ventricular CSF was studied after lumbar intrathecal administration. In the ventricular fluid peak concentrations up to 1.5×10–4 M (37 g/ml) were achieved 4–8 h after lumbar injection of cytarabine of 45 mg/m2. The concentration of cytarabine decreased slowly with a half-time of 2.16 h thus providing therapeutic concentrations in the cerebral ventricles for more than 24 h.
Zusammenfassung Die Verteilung von Cytosinarabinosid nach lumbaler intrathekaler Injektion im ventrikulären Liquor cerebrospinalis wurde untersucht.Nach lumbaler intrathekaler Injektion von 45 mg Cytosinarabinosid (Alexan®) pro m2 Körperoberfläche wurde im ventrikulären Liquor eine Höchstkonzentration von 1,5×10–4 M (37 g/ml) 4–8 h nach Applikation erreicht. Die Konzentration von Cytosinarabinosid im ventrikulären Liquor fiel langsam mit einer Halbwertszeit von 2,16 h ab. Bei lumbaler Applikation wurden bei dieser Untersuchung therapeutische Konzentrationen von Cytosinarabinosid in den cerebralen Ventrikeln für mehr als 24 h erreicht.
  相似文献   
99.
Summary Interferon-alpha (IFN-) and interleukin-2 (Il-2) are effective as single agents in metastatic renal cell cancer (RCC) with response rates of 15–30%. Additionally, IFN- is assumed to act synergistically with Il-2 in the induction of lymphokine-activated killer cells. (LAK cells) in vitro. With the aims of increasing the response rate by combining both cytokines and of reducing side effects, we started a clinical trial with a daily alternating schedule of 10×106 units/m2 s.c. rIFN-2b (Essex, Munich, FRG) and 3×106 Cetus units/m2 rIL-2 (EuroCetus, Frankfurt, FRG) in the form of 1 h infusions over a period of 14 days. Patients found to have progressive disease after two cycles of therapy were withdrawn from the study; patients with stable disease or better received two further cycles.Of the 27 patients included in the study, 22 (16 male, 6 female) are evaluable for response. In 1 patient with multiple pulmonary metastases complete remission was achieved, in 5 patients partial remission, and in 2 a minor response. The schedule was practicable; the main side effects were influenza-like symptoms, fatigue and hypotension. Some patients suffered from arthralgias and erythemas up to 3 weeks after finishing the therapy cycle. On the whole, the side effects seem to be less severe than those arising from schedules using continuous Il-2 infusions.This work was supported by Grant No. 01GA8802 of the Bundesministerium für Forschung und Technologie (BMFT)  相似文献   
100.
The purpose of this study was to investigate seniors' comparative music preference for four generic styles including art music, country music, popular music of today, and traditional jazz. The study also attempted to identify certain variables that have an effect on preference. Sixty-three subjects with a mean age of 82.5 from four nursing homes in the South Central Michigan area participated in the study. An interview and musical preference test were administered to the subjects individually. The listening test consisted of 16 music selections, four from each style. The seniors judged how much they liked the selections on a scale from 1 to 5, with 5 indicating greatest preference. Results indicated that country music style was preferred the most, followed by traditional jazz, art music, and lastly popular music. Variables that were found to affect preference were education level, community size in which the seniors grew up, and music training outside the school setting.  相似文献   
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