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Any reasoning concerning the brain must face two different objects: the organ-brain, and the metaphoric-brain. Because we know so little about the true nature of brain/mind relations, we have to be extremely careful and humble when coping with brain and mind. It is necessary above all to make a clear distinction between reality and fantasies, between organ-brain and metaphoric-brain. 相似文献
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MJ Tassignon V De Groot F Vervecken Y Van Tenten 《Canadian Metallurgical Quarterly》1998,24(10):1333-1338
PURPOSE: To observe the posterior continuous curvilinear capsulorhexis (PCCC) after cataract surgery in control eyes and eyes with an increased risk for postoperative inflammation. SETTING: Department of Ophthalmology, University Hospital Antwerp, Belgium. METHODS: After phacoemulsification, a PCCC was performed before intraocular lens (IOL) implantation in 20 eyes of 18 patients with ocular or systemic conditions that predisposed them for increased postoperative inflammation; e.g., diabetes, uveitis, retinitis pigmentosa (inflammation group). These eyes were compared with 20 eyes of 16 patients who had the same surgical procedure but did not present a history of medical or ocular pathology (control group). The postoperative follow-up was 6 months to 3 years. Reclosure of the PCCC was evaluated by anterior segment photographs. The reclosure was classified as partial when newly formed tissue was present at the PCCC margin and total when the proliferation covered the entire PCCC area. RESULTS: Three types of PCCC reclosure were found: fibrotic, Elschnig pearl or multilayer, and monolayer. All 3 were seen within or at the margin of the PCCC area. Reclosure (total and partial) occurred in 8 eyes (40%) in the control group and 10 (50%) in the inflammation group. Total reclosure was more frequent in the inflammation group (4 eyes [20%]) than in the control group (1 eye [5%]). Monolayered or multilayered cellular proliferation was present in 8 eyes (40%) in the control group and 4 eyes (20%) in the inflammation group; fibrotic proliferation was found in the inflammation group only (7 eyes [35%]). CONCLUSION: Reclosure of the PCCC occurred in both groups, although the frequency of reclosure was slightly higher in the inflammation group. Although PCCC does not prevent posterior capsule opacification in all cases, it is useful in specific situations. 相似文献
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OBJECTIVE: To compare effects of N(G)-monomethyl-L-arginine (L-NMMA; a NO synthase inhibitor) and L-arginine (a NO synthase substrate) on haemodynamics in healthy men at rest and during exercise. METHODS: We infused L-NMMA and saline placebo intravenously in two groups of eight healthy men. Each group underwent a two-phase, randomized, single-blind crossover study. Men in one group received 3 mg/kg L-NMMA and men in the other group received 6 mg/kg L-NMMA. Haemodynamic measurements were performed before, during and after a 12 min stepped exercise protocol starting 6 min after the intravenous infusion. A further six men received, according to the same study design, 30 g L-arginine over 30 min and saline placebo before exercise. Blood pressure was measured by sphygmomanometry and cardiac output by bioimpedance, allowing computation of total systemic vascular resistance index (SVRI). RESULTS: Infusion of 6 mg/kg L-NMMA into men at rest produced modest increases (compared with effect of saline placebo) in systolic and diastolic blood pressures of 4.1 +/- 1.1 and 12.6 +/- 3.5%, respectively (means +/- SEM, P < 0.01 for both comparisons) and a marked increase in SVRI of 39.2 +/- 5.2% (P < 0.01). Cardiac index and heart rate were 22.0 +/- 3.3 and 17.0 +/- 4.4% lower after administration of L-NMMA (P < 0.01 for each comparison) than after infusion of saline placebo. During exercise there was no significant difference between total SVRI after infusions of L-NMMA and saline (difference not significant, diminished with increasing exercise). Six minutes into recovery the difference between total SVRI after infusions of L-NMMA and saline reappeared with SVRI 25 +/- 6.9% higher after infusion of L-NMMA than after infusion of saline (P < 0.01). Administration of L-arginine had no significant effect on haemodynamics in men at rest, during exercise and during recovery. CONCLUSIONS: Effects of L-NMMA on total systemic vascular resistance during exercise are less marked than are those on subjects at rest, probably because vasodilatation of resistance vessels of skeletal muscle during exercise is mediated mainly by factors other than NO. Our results also suggest that NO synthesis in healthy men is not substrate limited either at rest or during exercise. 相似文献
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PURPOSE: To report a clinicopathologic correlation of angiosarcoma affecting the eyelid skin. METHODS: An 82-year-old man developed multiple bruise-like maculopapular lesions, subcutaneous nodules, and diffuse edema over his scalp, face, and eyelids. Biopsy disclosed angiosarcoma, and the patient was treated with wide-field external beam radiotherapy (5,000 cGy). RESULTS: He responded to radiotherapy with partial regression of the tumor. Twelve months later, he developed extensive lymphedema secondary to the residual tumor. He was also found to have parotid gland and bone metastases, treated with radiotherapy. The patient died of widespread bone metastases 3 months later. CONCLUSIONS: Angiosarcoma is a rare skin tumor that has a poor prognosis despite treatment. It should be considered in the differential diagnosis of eyelid tumors and edema because it may affect only the central portion of the face. 相似文献
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AIM: To study the behaviour of residual lens epithelial cells after capsulorhexis and expression of material from the isolated lens. METHODS: Human and bovine lens capsules were isolated, sterile non-toxic silicone rings inserted, and the preparations placed in organ culture for up to 12 weeks. Cell coverage of the posterior lens capsule was recorded and the capsules were examined, both pre- and post-coverage, for (a) proliferative activity and (b) cytoskeletal components. RESULTS: After a lag period outgrowth was observed across the posterior capsule. The rate of cell coverage was dependent upon both species and the presence or absence of serum. The proliferative activity of the cells was greatest at or near the leading edge and decreased once covered. Wrinkles became visible in the posterior capsule during the late stages of precoverage and increased in both number and complexity. All cells on both the human and bovine posterior capsules contained F-actin and vimentin and the majority were immunolabelled for alpha-smooth muscle actin (alpha-SMA). CONCLUSIONS: This model exhibits many of the in vivo characteristics of the lens capsule after extracapsular surgery and may prove useful in further elucidating the cellular mechanisms of posterior capsule opacification. 相似文献
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On account of its principle, ultrasound tomography cannot be recommended as a screening method for intestinal tumors; nevertheless, it may sometimes demonstrate larger tumors not producing typical signs. These neoplasms show a characteristic pattern ("cockade phenomenon"). In the region of the antrum they appear occasionally as a rigid thickening of the gastric wall. The nature of such an expansive lesion may be evaluated quickly and safely by a fine-needle puncture performed under sonographic control. No complications have been observed so far. 相似文献
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TL Hubbard 《Canadian Metallurgical Quarterly》1996,22(4):1049-1060
In 3 experiments, observers witnessed a target moving along a circular orbit and indicated the location at which the target vanished. The judged vanishing point was displaced forward in the direction of implied momentum and inward in the direction of implied centripetal force. In general, increases in either the angular velocity of the target or the radius length of the orbit increased the magnitude of forward displacement. If both angular velocity and radius length were varied, then increases in either angular velocity or radius length also increased the magnitude of inward displacement. The displacement patterns were consistent with hypotheses that analogues of momentum and centripetal force were incorporated into the representational system. A framework is proposed that accounts for (a) the forward and inward displacements and (b) naive-physics data on the spiral tube problem previously interpreted as suggesting a belief in a naive curvilinear-impetus principle. 相似文献
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AR Zarate 《Canadian Metallurgical Quarterly》1998,44(5):M549-M554
A new venous needle (VN) that also can be used as an arterial needle (AN) has been designed to diminish the undesirable hemodynamic effects of dialysis with high blood flow rate (300-600 ml/min) in arteriovenous polytetrafluoroethylene grafts, and in accesses of short length (U.S. Patent No. 5,662,619). The preferred embodiment has one distal opening, two lateral openings, and two diverters located in the interior surface of the shaft adjacent to each lateral opening. The diverters facilitate the flow of blood to the outside of the needle through the lateral openings. The new VN ejects three jets of blood, contrary to the currently used VN, which ejects one jet of high velocity. This decreases the velocity of the VN flow and the velocity; turbulence; wall shear stress; and positive pressure of the flow, past the VN, during dialysis. These may decrease the endothelial damage, intimal hyperplasia, stenoses, thromboses, and recirculation of dialysis blood (RODB). When used as an AN, the new needle lowers the negative pressure surrounding the AN and the RODB. In summary, the new needle may decrease the complications and prolong the life span of the accesses and improve the performance of dialysis. 相似文献
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Zhou Jing; Shin Shung Jae; Brass Daniel J.; Choi Jaepil; Zhang Zhi-Xue 《Canadian Metallurgical Quarterly》2009,94(6):1544
Taking an interactional perspective on creativity, the authors examined the influence of social networks and conformity value on employees’ creativity. They theorized and found a curvilinear relationship between number of weak ties and creativity such that employees exhibited greater creativity when their number of weak ties was at intermediate levels rather than at lower or higher levels. In addition, employees’ conformity value moderated the curvilinear relationship between number of weak ties and creativity such that employees exhibited greater creativity at intermediate levels of number of weak ties when conformity was low than when it was high. A proper match between personal values and network ties is critical for understanding creativity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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L. V. Bulanov 《Metallurgist》2006,50(5-6):320-324
An engineering method has been developed to calculate an efficient length for the vertical section of continuous casters on
which the semifinished product undergoes bending and straightening. The method, recommended for use by designers, was developed
by analyzing the ratio of the volumes of the melt in which nonmetallic inclusions do and do not rise to the melt’s surface.
The method makes it possible to quantitatively analyze the efficiency of the top section of the channel proposed for new casters
to alleviate the effects of nonmetallic inclusions. The efficiency of this section is evaluated in relation to its geometry,
the base radius of the caster, the thickness of the continuous-cast semifinished product, and casting speed.
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Translated from Metallurg, No. 6, pp. 51–53, June, 2006. 相似文献
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An experimental model of acute compartment syndrome involving the anterolateral compartment of the hindlimb in dogs was used to compare three methods of measurement of intracompartmental pressure: the simple-needle technique, use of the slit catheter, and use of the side-ported needle. No statistical difference was found between the values obtained with the slit catheter and those obtained with the side-ported needle; the mean difference was 1.4 millimeters of mercury throughout the range of compartment pressures that were measured. The side-ported needle appeared to be as accurate as the slit catheter for the measurement of compartment pressures (p = 0.355, 1-beta = 0.9). The values obtained with use of the simple needle were consistently higher than those obtained with the other two methods (p < 0.001): an average of 18.3 millimeters of mercury higher than the values measured with the slit catheter and 19.3 millimeters of mercury higher than those measured with the side-ported needle. Clinically, the side-ported needle or the slit catheter can be used to obtain accurate measurements of compartment pressure. Use of the simple 18-gauge needle is not recommended for this purpose. 相似文献
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KP Wang 《Canadian Metallurgical Quarterly》1995,16(3):535-552
In summary, knowledge of the exact location of lymph nodes in mediastinum and hilar areas and their relationship to the puncture site of TBNA is the first step to a successful TBNA. The necessity to determine the N3 status and multistation status of patients with bronchogenic carcinoma being evaluated for surgery and the current financial restraint of the medical care system further highlight the potential of this simple, effective, and safe procedure. TBNA can markedly enhance the diagnostic yield of flexible bronchoscopy. TBNA and PCNA are complimentary procedures. 相似文献