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881.
Kleinman BS Frey K VanDrunen M Sheikh T DiPinto D Mason R Smith T 《Anesthesiology》2002,97(2):298-305
BACKGROUND: Diaphragmatic excursion during spontaneous ventilation (SV) in normal supine volunteers is greatest in the dependent regions (bottom). During positive pressure ventilation (PPV) after anesthesia and neuromuscular blockade and depending on tidal volume, the nondependent region (top) undergoes the greatest excursion, or the diaphragm moves uniformly. The purpose of this study was to compare diaphragmatic excursion (during SV and PPV) in patients with chronic obstructive pulmonary disease (COPD) with patients having normal pulmonary function. METHODS: Twelve COPD patients and 12 normal control subjects were compared. Cross-table diaphragmatic fluoroscopy was performed while patients breathed spontaneously. After anesthetic induction and pharmacologic paralysis and during PPV, diaphragmatic fluoroscopy was repeated. For analytic purposes, the diaphragm was divided into three segments: top, middle, and bottom. Percentage of excursion of each segment during SV and PPV in normal subjects was compared with the percentage of excursion of each segment in patients with COPD. RESULTS: There was no significant difference in the pattern of regional diaphragmatic excursion (as a percentage of total excursion)-top, middle, bottom-when comparing COPD patients with control subjects during SV and PPV. In the control subjects, regional diaphragmatic excursion was 16 +/- (5), 33 +/- (5), 51 +/- (4) during SV and 49 +/- (13), 32 +/- (6), 19 +/- (9) during PPV. In COPD patients, regional diaphragmatic excursion was 18 +/- (7), 34 +/- (5), 49 +/- (7) during SV and 47 +/- (10), 32 +/- (6), 21 +/- (9) during PPV. CONCLUSION: Regional diaphragmatic excursion in patients with COPD during SV and PPV is similar to that in persons with normal pulmonary function. 相似文献
882.
883.
Sheikh RA Romano PS Prindiville TP Yasmeen S Trudeau W 《Journal of clinical gastroenterology》2002,34(5):529-532
BACKGROUND: Ticlopidine is a novel antiplatelet agent used alone or in combination with aspirin and anticoagulants in the treatment and prevention of various vascular diseases. Gastrointestinal side effects, including bleeding, have been reported with use of ticlopidine in most of the vascular prevention trials. We studied the endoscopic evidence of mucosal damage in patients taking ticlopidine compared with patients taking aspirin/nonsteroidal antiinflammatory drugs (NSAIDs) and matched controls. STUDY: We performed a longitudinal review of gastrointestinal endoscopy, pharmacy databases, and medical records of patients referred to our service over a period of 6 months for endoscopic evaluation of upper gastrointestinal bleeding, unexplained anemia, or abdominal pain. Data were collected and analyzed for 55 patients taking ticlopidine, 77 age- and gender-matched patients taking aspirin or NSAIDs, and 560 age- and gender-matched control patients not taking any of these medications. RESULTS: The overall prevalence of ulcers was marginally higher in the aspirin/NSAID group than in the ticlopidine group (35% vs. 29%) and was significantly higher among patients taking aspirin, NSAIDs, or ticlopidine than among controls (15%). Gastritis was also noted more frequently in the aspirin/NSAID and ticlopidine groups than in the control group. Endoscopic evidence of esophagitis was significantly more frequent in the control group than in the aspirin/NSAID and ticlopidine groups. There was no significant difference across groups in the prevalence of ulcers, gastritis, or esophagitis. CONCLUSIONS: Patients taking ticlopidine are more likely to have endoscopic evidence of mucosal damage than matched control patients and are nearly as likely to have such damage as endoscopically evaluated patients taking aspirin or NSAIDs. However, these findings must be confirmed using prospective cohort data for patients in primary care settings, to avoid referral bias. 相似文献
884.
Regulation of retinal vascular endothelial growth factor and receptors in rabbits exposed to hyperoxia 总被引:5,自引:0,他引:5
Ozaki NK Beharry KD Nishihara KC Akmal Y Ang JG Sheikh R Modanlou HD 《Investigative ophthalmology & visual science》2002,43(5):1546-1557
PURPOSE: To evaluate the molecular responses of vascular endothelial growth factor (VEGF) and its receptors to dexamethasone (Dex) and celecoxib (Cel) during hyperoxia and during hyperoxia followed by recovery in room air, in newborn rabbit retinas. METHODS: Newborn rabbits at 3 days postnatal age (n = 96) received room air or oxygen (80%-100%) for 4 days, during which they were administered saline (Sal), Dex, vehicle (Veh), or Cel (n = 12/treatment group). Six animals from each group were killed immediately after hyperoxia (or room air) and the remainder exposed to room air for 5 days. Retinal mRNA expression of VEGF(121), VEGF(165), VEGF receptor-1 (VEGFR-1, or Flt-1), and VEGFR-2 (or KDR/Flk-1) was determined. RESULTS: Hyperoxia resulted in increased retinal expression of mRNA of the VEGF splice variants in the groups treated with Sal, Dex, and Veh, whereas a decrease in VEGF(121) was noted in the Cel-treated group. In contrast, retinal Flt-1 receptor mRNA was markedly increased in the Cel-treated group only, whereas retinal VEGFR-2 (KDR/Flk-1) receptor mRNA was suppressed in all the treatment groups. Hyperoxia followed by recovery in room air resulted in a minimal decrease in expression of retinal Flt-1 mRNA in the Sal and Dex groups. Cel treatment abolished its expression. CONCLUSIONS: The findings of increased retinal expression of VEGF mRNA in the newborn rabbit in response to hyperoxia are most likely due to species differences. Selective targeting of VEGF(121) and Flt-1 mRNA by Cel may represent one regulatory pathway for their anti-inflammatory effects. Further studies are needed to evaluate the therapeutic benefits of cyclooxygenase (COX)-2 inhibitors for the treatment and/or prevention of diseases associated with neovascularization. 相似文献
885.
Developmental dysplasia of the hip in South Australia in 1991: Prevalence and risk factors 总被引:1,自引:0,他引:1
BC YIV R SAIDIN PJ CUNDY JD TGETGEL J AGUILAR KA McCAUL RJ KEANE A CHAN H SCOTT 《Journal of paediatrics and child health》1997,33(2):151-156
To determine the prevalence of developmental dysplasia of the hip (DDH) in South Australia (SA) in 1991, the proportion of cases detected in the neonatal period and the perinatal risk factors for DDH.
Cases of DDH born in SA in 1991 were identified from multiple sources and their clinical data linked to perinatal data provided by midwives; five controls per case were obtained randomly from SA livebirths without congenital abnormalities and adjusted odds ratios (OR) for potential risk factors obtained by logistic regression analysis. South Australia perinatal data were also used to estimate numbers of births with perinatal risk factors for targeted screening.
Two hundred and six cases of isolated DDH were identified, giving a prevalence of 10.5 per 1000 births. Of these, 173 (84%) had been detected in the neonatal period. The perinatal risk factors for DDH were identified as breech presentation (OR 9.65), female babies (OR 4.04), first births (OR 1.91) and maternal age of 25 years or more (OR 1.53). Screening breech and firstborn female babies (23% of births) would yield approximately 51% of cases of DDH.
Isolated DDH had a prevalence of 10.5 per 1000 births and 84% of cases had been detected in the neonatal period in SA. Repeated screening during infancy of 'at risk' groups of babies is recommended. 相似文献
Methodology:
Cases of DDH born in SA in 1991 were identified from multiple sources and their clinical data linked to perinatal data provided by midwives; five controls per case were obtained randomly from SA livebirths without congenital abnormalities and adjusted odds ratios (OR) for potential risk factors obtained by logistic regression analysis. South Australia perinatal data were also used to estimate numbers of births with perinatal risk factors for targeted screening.
Results:
Two hundred and six cases of isolated DDH were identified, giving a prevalence of 10.5 per 1000 births. Of these, 173 (84%) had been detected in the neonatal period. The perinatal risk factors for DDH were identified as breech presentation (OR 9.65), female babies (OR 4.04), first births (OR 1.91) and maternal age of 25 years or more (OR 1.53). Screening breech and firstborn female babies (23% of births) would yield approximately 51% of cases of DDH.
Conclusions:
Isolated DDH had a prevalence of 10.5 per 1000 births and 84% of cases had been detected in the neonatal period in SA. Repeated screening during infancy of 'at risk' groups of babies is recommended. 相似文献
886.
Retinoids mediate their actions via RARs (retinoic acid receptors) and RXRs (retinoid X receptors). Each classes of these nuclear retinoid receptor is further subdivided into three species namely α, β and γ. Recent studies demonstrate that ER - positive HBC cell lines are sensitive and ER -negative cell lines are resistant to growth inhibitory effects of retinoic acid (RA). In this study we look at the expresion of RARs and RXRs in 6 HBC cell lines, we found only RARα mRNA level was strong correlated with ER - status. To further investigate the major role of RARα in retinoid - mediated inhibition of growth, we transfected RARα cDNA in two RA - resistant ER - negative HBC cell lines. Analyses of different clonal populations of RARα transfectants from each cell line revealed growth inhibition by retinoids. Our results demonstrates that RARα plays a major role in mediating retinoids inhibition of growth in HBC cells and adequate levels are required for such actions. 相似文献
887.
888.
Shehab AB Shaheen FA Fallatah A Sheikh IA Gabal MS Al-Koussi M 《The Journal of the Egyptian Public Health Association》1994,69(5-6):379-395
The utilization of living's kidneys as renal replacement for Chronic Renal Failure (CRF) patients was debated for long time. However, the lack of renal pool in one hand and the proper employment of modern investigatory armamentarium in another hand could justify such donation. Living related donors (LRD) are subjected to extensive non invasive investigations to assess their general fitness for donation and split renal function. The impact of uni-nephrectomy on the renal function was studied in 25 LRD. Serum Creatinine (S. Cr.) Creatinine Clearance (Cr. Cl.) and renographic clearance tests for total and split renal function and renal volume using ultrasound were determined before and 3 months after donation. An initial increase in s.cr was seen in 76% of donors, but all levels are within normal range. Total kidney function by cr.cl showed significant drop by 36% of the pre donated value. Remaining kidney clearance increased by 5% to 64% with an average of 34% of the pre donated level as measured by Tc 99m DTPA renography. Following nephrectomy, compensatory hypertrophy of the remaining kidney attributed to an increase in the renal volume of 15%. In conclusion, kidney donation from living's is safe. Cr. clearance using the chemical method is a good screening test for potential LRD and for monitoring the renal function after donation. Renographic clearance using Tc 99m DTPA is as excellent useful test for split renal function in LRD work up. Long-term follow up might be needed. 相似文献
889.
Bidstrup BP Hunt BJ Sheikh S Parratt RN Bidstrup JM Sapsford RN 《The Annals of thoracic surgery》2000,69(2):541-547
BACKGROUND: Aspirin therapy is widely used in the treatment of cardiac disease. It has been recognized as a causative factor for increased bleeding and blood loss after open heart operations. METHODS: To determine whether high-dose aprotinin maintained its efficacy in reducing blood loss in the presence of aspirin pretreatment in patients undergoing aortocoronary bypass, we performed a double blind study on 60 adult patients. Half received high-dose aprotinin (Trasylol) and half placebo. RESULTS: Total hemoglobin loss, the primary efficacy variable was reduced from 36.1 +/- 31.4 g (mean +/- SD) to 14.1 +/- 16.0 g (p = 0.002). Blood loss was reduced intraoperatively and total loss was reduced from 837.3 mL +/- 404.9 mL to 368.7 mL +/- 164.3 mL (p < 0.001). The number of patients who did not receive any donor blood products was significantly higher in the aprotinin-treated patients (56.7% versus 23.3%, p = 0.008). Activation of the clotting cascade was significantly less in the treated patients toward the end of cardiopulmonary bypass both by measurement of thrombin-antithrombin III complex (p < 0.0001) and prothrombin fragment 1 + 2 (p < 0.0001). D-Dimer generation was significantly less from the onset of bypass and after reversal of heparin in the aprotinin-treated patients (p < 0.0001). CONCLUSIONS: High-dose aprotinin was highly effective in reducing bleeding in this high-risk group of patients. Biochemical analyses suggest the mechanism by which aspirin increases blood loss after cardiopulmonary bypass is different from the blood-preserving effects of aprotinin, which is acting as an antifibrinolytic agent. 相似文献
890.
The clinical course of patients with suspected pulmonary embolism and a negative pulmonary arteriogram 总被引:4,自引:0,他引:4
Novelline RA; Baltarowich OH; Athanasoulis CA; Waltman AC; Greenfield AJ; McKusick KA 《Radiology》1978,126(3):561-567
Selective pulmonary arteriography, with superselective magnification views of the lung bases or other areas where abnormalities are shown on perfusion lung scans, performed within 24-48 hours after the onset of symptoms, can effectively rule out clinically significant pulmonary thromboembolism. One hundred and eighty consecutive patients (minimum follow up, six months) with suspected pulmonary embolism and negative pulmonary arteriograms were studied. Not one of the 167 untreated patients died as a result of thromboembolic disease during the acute illness (20 died from unrelated causes), and none of the 147 patients who survived suffered "recurrent embolism" during follow up. 相似文献