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71.
Beris AE Payatakes AH Kostopoulos VK Korompilias AV Mavrodontidis AN Vekris MD Kontogeorgakos VA Soucacos PN 《The Orthopedic clinics of North America》2004,35(3):335-43, ix
Femoral neck fractures, frequently complicated by non-union and femoral head osteonecrosis,present a difficult clinical situation, especially when young patients are concerned.Existing treatment options are valgus osteotomy to address the biomechanical factors or bone grafting to address the biologic factor. The authors describe the operative technique and results of combined subtrochanteric valgus osteotomy and free vascularized fibular grafting in management of five young patients with both non-union and avascular necrosis. 相似文献
72.
Freiman TM Surges R Vougioukas VI Hubbe U Talazko J Zentner J Honegger J Schulze-Bonhage A 《Journal of neurosurgery》2004,101(5):846-853
The development of visual hallucinations after loss of vision is known as the Charles Bonnet syndrome. This phenomenon was first described in 1760 by Charles Bonnet and others during their observations of elderly patients with degeneration of the retina or cornea. To date a clear association between visual hallucinations and neurosurgical procedures has not been reported. Because of their clear demarcation, however, surgical lesions in the cerebrum offer a unique opportunity to determine the pathoanatomical aspects of visual hallucinations. During a 3-year period, 41 consecutive patients who acquired visual field defects after neurosurgery were examined for the occurrence of visual hallucination. Postoperatively, four of these patients experienced visual hallucinations. In two of them an upper quadrantanopia developed after the patients had undergone selective amygdalohippocampectomy. In the other two patients a complete hemianopia developed, in one case after resection of a parietal astrocytoma and in the other after resection of an occipital glioblastoma multiforme. The visual hallucinations were transient and gradually disappeared between 4 days and 6 months postoperatively. The patients were aware of the fact that their hallucinations were fictitious and displayed no psychosis. Electroencephalographic recordings were obtained in only two patients and epileptic discharges were found. Deafferentiation of cortical association areas may lead to the spontaneous generation of complex visual phenomena. In the present series this phenomenon occurred in approximately 10% of patients with postoperative visual field defects. In all four cases the central optic radiation was damaged between the lateral geniculate nucleus and the primary visual cortex. The complex nature of the visual hallucination indicates that they were generated in visual association areas. 相似文献
73.
Kostopanagiotou G Siafaka I Sikiotis C Smyrniotis V 《Journal of clinical anesthesia》2004,16(6):458-460
We describe a patient with Bernard-Soulier syndrome who underwent emergency laparotomy for intraabdominal bleeding. Presentation of this recent case highlights some of the anesthetic and perioperative implications of the disease. Briefly, perioperative and anesthetic management of patients with Bernard-Soulier syndrome should include platelet transfusions and choice of appropriate anesthetic drugs and techniques. The potential benefit of desmopressin and corticosteroids should be considered. Thrombelastography, if available, is also useful. 相似文献
74.
Fountas KN Duwayri Y Kapsalaki E Dimopoulos VG Johnston KW Peppard SB Robinson JS 《Southern medical journal》2004,97(3):279-82; quiz 283
Two cases of epidural abscess as a complication of frontal sinusitis are presented. The diagnoses were suspected on the basis of history and were confirmed by magnetic resonance imaging and computed tomography. Both patients were treated successfully by means of surgery and intravenous antibiotics. One patient developed meningitis in the postoperative course and was treated by changing the antibiotic regimen. However, further follow-up in the outpatient clinic by physical examinations and brain computed tomography scans showed no longterm neurologic complications in either case. Intracranial suppuration, including epidural abscesses, can complicate acute and chronic frontal sinusitis. These complications are diagnosed by maintaining a high index of suspicion and using the appropriate neuroimaging studies without delay. 相似文献
75.
Papalois V Vlachos K Barlas A Zarka ZA El-Tayar A Hakim NS 《Bulletin of medical ethics》2004,(202):13-20
A shortage of organ donors and the large number of patients desperately waiting for kidney transplant have led to the search for new sources of transplantable organs. The waiting list has grown at an alarming rate resulting in increased waiting times and deaths. The introduction of non heart beating (NHB) donation programmes generates a lot of ethical issues. How should death of a patient be defined in the case of NHB donation? Is there a strict separation of responsibilities of the medical teams in the different phases of the procedure (patient treatment and actual donation)? How should consent be obtained? Is sufficient respect and care given to the patient and his family? How is the viability of the organs assessed and how should the organs be allocated? We believe that it is very important to debate these issues and to try to outline an ethical framework for NHB donation that can enjoy the widest possible community support. 相似文献
76.
Grigoryan RS Panosyan EH Seibel NL Gaynon PS Avramis IA Avramis VI 《In vivo (Athens, Greece)》2004,18(2):107-112
BACKGROUND: Deamination of asparagine (Asn) and glutamine (Gln) by asparaginases (ASNase) is associated with good prognosis in acute lymphoblastic leukemia (ALL). Chemotherapy drugs used for ALL may accelerate catabolism of other amino acids (AA). MATERIALS AND METHODS: We studied ASNase activity and changes of Asn, Gln, serine (Ser), threonine (Thr), histidine (His), proline (Pro) and arginine (Arg) levels and sought relationships in sera from 73 pediatric ALL patients, who received ASNase-containing chemotherapy. RESULTS: Asparaginase activity averaged 0.4+/-0.34 IU/ml (mean+/-SDEV) in all specimens. All AA decreased after treatment, ranging from 18.6%-82.6% of control. Asparaginase activity of 0.7 IU/ml provided 90% Asn and Gl deamination. The data were dichotomized in subsets of low ASNase (range 0.02-0.39 IU/ml, mean=0.17+/-0.09 IU/ml) and high ASNase (range 0.4-1.69 IU/ml and mean=0.72+/-0.32 IU/ml). Asparagine and Gln % deamination values were correlated with ASNase activity (p=0.0002 and p=0.0001). Similarly, decreases of Arg and Ser levels were also correlated, p =0.0009 and p=0.032, respectively. In the high ASNase subset, a 39% decrease of Arg and 26% of Ser was obtained. Low ASNase activity was correlated with lower Asn and Gln % deamination and with moderate decrease of Ser (14.6%) and Arg (19.6%). Threonine, Pro and His also decreased, but no correlations were obtained with ASNase activity. CONCLUSION: Asparagine, Gln and five other AA declined during ASNase treatment. Asparagine and Gln % deamination values are highly correlated with serum ASNase activity. Asparaginase may indirectly cause moderate depletion of serum Arg and Ser levels, providing an enhancement in leukemia blasts apoptosis. Toxicity from the ASNase and other drugs could enhance the decrease of AA serum levels. Further studies are needed to verify these findings and their potential clinical importance in the treatment of ALL patients. 相似文献
77.
Vassilios?P.?Kozobolis Emmanouil?V.?ChristodoulakisEmail author Irene?I.?Naoumidi Charalambos?S.?Siganos Efstathios?T.?Detorakis loannis?G.?Pallikaris 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2004,242(6):478-483
Background Tear secretion and tear film stability seem to be influenced by pseudoexfoliation syndrome (PEX). Histopathological evaluation of conjunctival goblet cells in PEX patients might explain the influence on tear film stability.Methods In a prospective, cross-sectional study, 40 eyes of 40 patients with PEX (study group) had measurement of Schirmer test with anesthesia and break-up time prior to cataract surgery. At the end of an uneventful operation, a 1×1.5 mm sample of conjunctival tissue was obtained and light and electron microscopy were performed. Results were compared with a control group. Histology evaluation was masked. Primary outcome measures included Schirmer test with anesthesia, break-up time, goblet cell density and morphological character of conjunctiva and conjunctival goblet cells.Results Both Schirmer test and break-up time values were significantly lower (P=0.01 and P=0.001) in the PEX patients (mean 10.6 mm and 8.6 s respectively) than in the control group (13.4 mm and 12.3 s respectively). The number of goblet cells in patients with PEX compared with the control group showed no statistically significant difference (P=0.66). Use of trichrome stain revealed significant differences in the staining properties of goblet cells between patients with PEX and controls. On electron microscopy, typical pseudoexfoliation filaments were found in the connective tissue of conjunctiva of PEX patients. Remarkable changes of mucin pockets in the study group were also noticed; they had extremely irregular distribution, various forms of size and appearance and even complete collapse.Conclusion Pseudoexfoliation seems to alter basic features of goblet cell morphology, thus affecting tear film stability. Further studies are necessary to determine the exact mechanism. 相似文献
78.
Gazouli M Han Z Papadopoulos V 《The Journal of pharmacology and experimental therapeutics》2002,303(2):627-632
Peripheral-type benzodiazepine receptor (PBR) is an 18-kDa high-affinity cholesterol and drug ligand-binding protein involved in various cell functions, including cholesterol transport and steroid biosynthesis. To aid our investigation of the biological function of PBR, we have set out to identify functional antagonists. By screening phage display libraries, we have identified peptides that displace the high-affinity PBR benzodiazepine drug ligand, Ro5-4864 (4'-chlorodiazepam). Among these peptides, STPHSTP was the most potent (IC(50) = 10 microM). All of the isolated peptides showed a conserved motif STXXXXP. The role of these peptides in Leydig cell steroidogenesis was examined using a transducible peptide composed of the TAT domain of human immunodeficiency virus and the peptides under investigation. Synthesized peptides efficiently transduced into MA-10 Leydig cells, and the peptide TAT-STPHSTP inhibited Ro5-4864- and human chorionic gonadotropin-stimulated steroid production in a dose-dependent manner (ED(50) = 5 microM). TAT-STPHSTP behaved as a competitive PBR antagonist, which did not affect 22R-hydroxycholesterol-supported steroidogenesis. These results yield leads for the development of potent PBR antagonists and indicate that endogenous PBR agonist-receptor interaction is critical for hormone-induced steroidogenesis. 相似文献
79.
Ginkgo biloba extracts and cancer: a research area in its infancy 总被引:13,自引:0,他引:13
80.
PURPOSE: To explore the possibility of a relationship between increased use of computed tomography (CT) for diagnosis of appendicitis and increased occurrence of minimal or subtle CT and surgical findings. MATERIALS AND METHODS: Two groups, each with 50 consecutive patients who underwent CT before appendectomy in 1997 and 2000, were compared. CT scans and surgery-pathology reports were evaluated on a six-grade scale from normal to abscess or inflammatory mass. The demographics, surgical techniques, hospital stay, and grade distribution for the two groups were compared, and the CT results were correlated with surgical findings. RESULTS: In 1997, CT was performed in 33% (50 of 152) of patients undergoing appendectomy, as compared with 59% (50 of 85) 3 years later (P <.001). There was excellent correlation between surgical-pathologic and CT grades (weighted kappa, 0.75; P <.001; Spearman rank correlation, 0.83). There was no significant difference in demographics, rate of surgery, or surgical techniques used, but there was a significant decrease in the median surgical-pathologic grades, from 3.0 to 2.5 (P =.05) for all patients and from 3.5 to 2.6 (P =.003) for patients who underwent CT. Similarly, the median CT grade decreased from 4 to 3 (P <.001). Seven patients had subtle CT findings in 1997 compared with 16 in 2000 (P =.004), and there was a significant decrease in mean hospital stay, from 2.8 days +/- 4 (SD) to 1.5 days +/- 2 (P =.008). CONCLUSION: With increased CT use, there were less severe imaging findings, including absence of periappendiceal stranding, and a significant decrease in surgical-pathologic severity of appendiceal disease and hospital stay. 相似文献