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971.
PURPOSE: To report anatomic and visual improvement after pars plana vitrectomy with gas tamponade for a lamellar macular hole with poor central visual acuity. DESIGN: Two interventional case reports. METHODS: Two patients with a lamellar macular hole underwent vitrectomy, internal limiting membrane peeling, and long-acting gas injection. Main outcome measures included best-corrected visual acuity, biomicroscopic appearance, and optical coherence tomography findings. RESULTS: Vitrectomy with gas tamponade resulted in biomicroscopic, functional, and tomographic improvement in both patients for follow-up periods of 12 months. CONCLUSIONS: Vitrectomy with gas tamponade may be an effective method for a lamellar macular hole with poor visual acuity.  相似文献   
972.
Trichoepithelioma is a benign skin tumor and is most commonly found on the face, however, there are few reports about its occurrence on the eyelids. It is not usually recognized because of its rarity, origin, biological potential, and controversial classification. The purpose of this paper is to report two cases of solitary trichoepithelioma on the eyelid, their histopathology and treatment. This lesion should be considered when a single solid nodule on the face appears, and can be differentiated from basal-cell carcinoma. Histopathologic confirmation is essential.  相似文献   
973.
We present a case of a 33-year-old man, who had a past history of a total pancreatectomy for duodenal malignant lymphoma complicated by life-threatening bleeding during chemotherapy at 23 years of age. He achieved complete remission and received no more chemotherapy. Around August 1999 he developed anemia, which failed to improve following intravenous administration of iron, and he was hospitalized. The cause of the anemia remained unclear and he received a blood transfusion. Because of the increasing frequency of transfusions, he was admitted to our hospital to evaluate his anemia in September 2000. On examinations, laboratory findings revealed a low level of serum vitamin B6 (B6) with iron deficiency. Intravenous administration of B6 was performed in addition to iron, with the result that the patient's hemoglobin level was kept at 10 g/dl without blood transfusion. An oral B6 administration test resulted in a low level of B6. These results suggest that B6 deficiency due to malabsorption may cause therapy-resistant anemia. Some reports say that B6 deficiency causes microcytic hypochromic anemia, since B6 is necessary for erythrocytic hemopoiesis as a coenzyme for heme biosynthesis. In the case of microcytic hypochromic anemia, if the cause is unclear, evaluation should be performed, taking the possibility of a hidden cause of B6 deficiency into consideration.  相似文献   
974.
975.
976.
We evaluated the usefulness of two-dimensional time-of-flight (2D TOF) MR venography (MRV) of the lower extremity using the respiratory compensation (RC) technique. In addition, six variations in patient positioning of the leg and knee were investigated to determine the best method of visualizing the deep popliteal veins and lower leg. All data sets were reviewed and graded for visualization of the deep veins at the pelvis, thigh, and leg portion (4-point scale) by two radiologists and three radiological technologists. The same veins demonstrated with various positions of the patient were also evaluated in the same manner. In conclusion, 2D TOF MRV with RC resulted in increased uniformity of vein signal in the pelvic area. Furthermore, we should position the patient's leg so as not to compress the vein at the posterior portion of the leg, and not to over-extend the knee joint. This enabled the best results to be obtained in MRV of the lower extremity.  相似文献   
977.
978.
Recently, we reported that the laminin alpha5 synthetic peptide A5G27 (RLVSYNGIIFFLK, residues 2,892-2,904) binds to the CD44 receptor of B16-F10 melanoma cells via the glycosaminoglycans on CD44 and inhibits tumor cell migration, invasion, and angiogenesis in a dominant-negative manner. Here, we have identified the potential mechanism of A5G27 activity using WiDr human colorectal carcinoma cells. WiDr cells bound to the laminin A5G27 peptide via the heparin-like and chondroitin sulfate B glycosaminoglycan side chains of CD44. Cell binding to fibroblast growth factor (FGF2) was blocked by laminin peptide A5G27 but not by either a scrambled version of this peptide or by another laminin peptide known to bind cell surface proteoglycans. FGF2 signaling involving tyrosine phosphorylation was also blocked by laminin peptide A5G27 but was not affected by peptide controls. Finally, we have shown that peptide A5G27 directly blocks FGF2 binding to heparin. Peptide A5G27 has sequence homology to a region on FGF2 that binds heparin and the FGF receptor and is important in FGF2 central cavity formation. We conclude that peptide A5G27 inhibits metastasis and angiogenesis by blocking FGF2 binding to the heparan sulfate side chains of CD44 variant 3, thus decreasing FGF2 bioactivity.  相似文献   
979.
Homi HM  Yang H  Pearlstein RD  Grocott HP 《Anesthesia and analgesia》2004,99(4):974-81, table of contents
Although the optimal hematocrit during cardiopulmonary bypass (CPB) is not defined, excessive hemodilution may lead to organ ischemia via a reduction in oxygen-carrying capacity uncompensated by autoregulatory and/or rheologic increases in organ blood flow. As a result, the consequences of hemodilution in patients at risk for cerebral ischemia are not clearly understood. We designed this study to evaluate the effects of hemodilution in the setting of focal cerebral ischemia during CPB. Wistar rats surgically prepared for CPB were randomized to either hemodilution (hemoglobin (Hb), 6 g/dL; n = 9) or control (Hb, 11 g/dL; n = 8) groups and subsequently exposed to focal cerebral ischemia induced by middle cerebral artery occlusion (MCAO). Immediately after the onset of MCAO (maintained for 90 min), 65 min of hypothermic (28 degrees C) CPB was initiated. Twenty-four hours later, functional neurological outcome and cerebral infarct volume were determined. Compared with controls, the hemodilution group had worse neurological performance (new score = 8 [2], hemodilution; versus 10 [2], control; P = 0.030) and larger total cerebral infarct volumes (182 +/- 84 mm(3), hemodilution; versus 103 +/- 58 mm(3), control; P = 0.043). In this experimental model of CPB with reversible MCAO-induced focal cerebral ischemia, hemodilution worsened neurological function and increased cerebral infarct volume.  相似文献   
980.
Compared to the neurologic morbidity of stroke and cognitive dysfunction, "other" neurologic complications involving injuries to the brachial plexus, phrenic nerve, cranial nerves, other peripheral nerves, as well as the visual pathways, have been disproportionately underrepresented in the cardiac surgery and anesthesiology literature. These injuries are often missed in the early postoperative period when attention is focused principally on recovery from the acute trespass of cardiac surgery and cardiopulmonary bypass. However, when these problems do become apparent, they can cause considerable discomfort and morbidity. An overview of the current concepts of injury mechanisms/etiology, diagnosis, prognosis, and when possible, prevention of these injuries is presented.  相似文献   
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