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41.
42.
Gracias VH Guillamondegui OD Stiefel MF Wilensky EM Bloom S Gupta R Pryor JP Reilly PM Leroux PD Schwab CW 《The Journal of trauma》2004,56(3):469-72; discussion 472-4
BACKGROUND: Cerebral hypoxia (cerebral cortical oxygenation [Pbro2] < 20 mm Hg) monitored by direct measurement has been shown in animal and small clinical studies to be associated with poor outcome. We present our preliminary results observing Pbro2 in patients with traumatic brain injury (TBI). METHODS: A prospective observational cohort study was performed. Institutional review board approval was obtained. All patients with TBI who required measurement of intracranial pressure (ICP), cerebral perfusion pressure (CPP), and Pbro2 because of a Glasgow Coma Scale score < 8 were enrolled. Data sets (ICP, CPP, Pbro2, positive end-expiratory pressure (PEEP), Pao2, and Paco2) were recorded during routine manipulation. Episodes of cerebral hypoxia were compared with episodes without. Results are displayed as mean +/- SEM; t test, chi2, and Fisher's exact test were used to answer questions of interest. RESULTS: One hundred eighty-one data sets were abstracted from 20 patients. Thirty-five episodes of regional cerebral hypoxia were identified in 14 patients. Compared with episodes of acceptable cerebral oxygenation, episodes of cerebral hypoxia were noted to be associated with a significantly lower mean Pao2 (144 +/- 14 vs. 165 +/- 8; p < 0.01) and higher mean PEEP (8.8 +/- 0.7 vs. 7.1 +/- 0.3; p < 0.01). Mean ICP and CPP measurements were similar between groups. In a univariate analysis, cerebral hypoxic episodes were associated with Pao2 < or = 100 mm Hg (p < 0.01) and PEEP > 5 cm H2O (p < 0.01), but not ICP > 20 mm Hg, CPP < or = 65 mm Hg, or Pac2 < or = 35 mm Hg. CONCLUSION: Cerebral oxymetry is confirmed safe in the patient with multiple injuries with TBI. Occult cerebral hypoxia is present in the traumatic brain injured patient despite normal traditional measurements of cerebral perfusion. Further research is necessary to determine whether management protocols aimed at the prevention of cerebral cortical hypoxia will affect outcome. 相似文献
43.
A rare case of true aneurysm of the profunda femoris artery (PFA) is reported. Surgical management consisted of ligation of the aneurysm and decompression of the sac. Presentation, diagnosis, and treatment of true PFA aneurysms are discussed and the English language literature is comprehensively reviewed. 相似文献
44.
Mitochondrial pro-apoptotic ARTS protein is lost in the majority of acute lymphoblastic leukemia patients 总被引:2,自引:0,他引:2
Elhasid R Sahar D Merling A Zivony Y Rotem A Ben-Arush M Izraeli S Bercovich D Larisch S 《Oncogene》2004,23(32):5468-5475
Acquired resistance towards apoptosis is the hallmark of most if not all types of cancer. We have previously identified and characterized ARTS, a broadly expressed protein localized to mitochondria. ARTS was initially shown to mediate TGF-beta induced apoptosis. Recently, we have found that high levels of ARTS induce apoptosis without additional pro-apoptotic stimuli. Further, ARTS promotes apoptosis in response to a wide variety of pro-apoptotic stimuli. Here, we report that the expression of ARTS is lost in all lymphoblasts of more than 70% of childhood acute lymphoblastic leukemia (ALL) patients. The loss of ARTS is specific, as the related non-apoptotic protein H5, bearing 83% identity to ARTS, is unaffected. During remission, ARTS expression is detected again in almost all patients. Two leukemic cell lines, ALL-1 and HL-60 lacking ARTS, were resistant to apoptotic induction by ara-C. Transfection of ARTS into these cells restored their ability to undergo apoptosis in response to this chemotherapeutic agent. We found that methylation process contributes to the loss of ARTS expression. We conclude that the loss of ARTS may provide a selective advantage for cells to escape apoptosis thereby contributing to their transformation to malignant lymphoblasts. We therefore propose that ARTS can function as a tumor suppressor protein in childhood ALL. 相似文献
45.
46.
Between one-third and one-half of the individuals who meet diagnostic criteria for schizophrenia remain actively ill despite optimal pharmacological treatment. These individuals tend to progressively deteriorate in terms of social and vocational functioning despite major public and private investments in their rehabilitation. For patients who do not respond to the first prescribed antipsychotic drug, current clinical practice is to switch to a second and a third drug, and eventually to clozapine, the only antipsychotic drug proven to be effective in treatment-refractory schizophrenia (TRS). Occasionally, two antipsychotics are given concomitantly or psychotropic drugs are added to antipsychotic drugs; however, very few empirical data exist to support this practice. Although there are many exceptions, patients who do not benefit from the first prescribed drug will not benefit from any pharmacological intervention. Therefore, efforts are under way to determine the reason for lack of response to available treatments and devise novel, more effective treatments. To be successful these efforts must result in a more specific definition of TRS, as well as in a better understanding of the illness pathophysiology and the mechanism of action of the drugs. 相似文献
47.
OBJECTIVE: To determine the long-term visual acuity (VA) outcome of eyes with ambulatory vision (20/80 or better) that were treated with transscleral laser cyclotherapy. DESIGN: Observational case series. PARTICIPANTS: Twenty-one eyes of 21 patients who had been treated with laser cyclotherapy and who had been followed up at least 1 year. METHODS: A retrospective chart review was conducted to record the prelaser best-corrected VA and then the last available post laser VA and duration of follow-up. Additional laser or surgical interventions for glaucoma control were also recorded. MAIN OUTCOME MEASURES: Changes in VA from pretreatment to last available examination. RESULTS: The 21 eyes were followed for a mean of 40.7 months (range, 13-88 months); 17 eyes had a final vision within 1 line of the prelaser VA. One eye improved 3 lines, and 3 eyes deteriorated 3 or more lines. CONCLUSIONS: Most eyes with 20/80 or better VA maintained close to that acuity after laser cyclotherapy after a mean follow-up of 40.7 months. These good visual results offer support for those who believe that the indications for laser cyclotherapy should not be limited to eyes with poor VA or potential. 相似文献
48.
Akyol D Hajdu C Ferber A O'reilly-Green C Giancotti FR Dorsett BH Opher E Divon MY 《American journal of obstetrics and gynecology》2003,189(1):155-158
OBJECTIVE: The purpose of this study was to evaluate the correlation between placental and umbilical cord nucleated red blood cell counts. STUDY DESIGN: Eighty placentas and their matched umbilical cord blood samples were collected prospectively immediately after delivery. In vitro fine-needle aspiration biopsy specimens were used to obtain placental tissue samples. Nucleated red blood cells were counted by both manual microscopy and flow cytometry. Statistical analysis included Wilcoxon signed rank test and Spearman correlation. RESULTS: The median nucleated red blood cell counts/100 white blood cell counts for manual microscopy in umbilical cord blood; placental samples were 7.5 and 3.0, respectively (P <.0001). The median nucleated red blood cell counts for flow cytometric determination in umbilical cord blood and placental samples were 11.3 and 8.6, respectively (P <.0001). The Spearman correlation between manually counted umbilical cord blood samples and the placental tissue specimens was 0.66 (P <.0001). The Spearman correlation between flow cytometrically counted umbilical cord blood nucleated red blood cell and nucleated red blood cell counts that were obtained from the placenta was statistically significant (r = 0.74, P <.0001). The Spearman correlation between manual microscopy and flow cytometry for umbilical cord samples and their matched placental tissue specimens were 0.80 and 0.58, respectively, with all probability values at <.0001. CONCLUSION: Previous studies have reported an association between acute and chronic hypoxia and elevated nucleated red blood cells. Our results indicate that in vitro placental nucleated red blood cell counts correlate with umbilical cord nucleated red blood cell counts and suggest that antenatal evaluation of fetal nucleated red blood cells could be achieved by placental fine-needle aspiration biopsy. 相似文献
49.
Doppler evaluation of the fetus 总被引:2,自引:0,他引:2
50.
Wilensky RL 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》2003,17(1):63-73
Restenosis following percutaneous coronary transluminal angioplasty and stenting remains a significant problem, occurring in 15–50% of patients within 6–9 months of the intervention. Several pharmacological approaches to reduce restenosis have been evaluated but to date none have been approved for this indication. Angiotensin II has been implicated in the development of restenosis through several physiologic mechanisms, and thus control of the renin-angiotensin system may be a potential target for its prevention. Although human trials have shown that angiotensin-converting enzyme inhibitors do not reduce the risk of restenosis, early data suggest that the selective AT1 angiotensin receptor blocker valsartan may be effective in preventing in-stent restenosis in patients with complex lesions. 相似文献