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141.
Dr. Kenneth E. Olive Eric D. Grassman COL USAF MC 《Journal of general internal medicine》1990,5(6):470-473
OBJECTIVE: To determine whether echocardiography affects the decisions to use beta blockers or to recommend bacterial endocarditis prophylaxis in patients suspected of having mitral valve prolapse (MVP). DESIGN: Retrospective review of echocardiograms and clinical records. SETTING: Military tertiary care hospital. PATIENTS: 127 patients with clinically suspected MVP (105) or incidentally discovered MVP (22). MAIN RESULTS: Beta blockers were used more often in patients with suspected MVP and positive echocardiograms (45%) than in patients with normal echocardiograms (13%, p less than 0.001). Bacterial endocarditis prophylaxis was recommended more often in patients with suspected MVP and positive echocardiograms (65%) than in patients with normal echocardiograms (11%, p less than 0.001). Presence or absence of a murmur did not influence the decision to recommend bacterial endocarditis prophylaxis. Patients in whom MVP was incidentally discovered were unlikely to receive either beta blockers or the recommendation for bacterial endocarditis prophylaxis. CONCLUSIONS: The results of echocardiography affect the decisions to use beta blockers or to recommend bacterial endocarditis prophylaxis in patients with suspected MVP. 相似文献
142.
Comorbidity weights have become an important tool in longitudinal outcome studies. They should be tailored toward the population and the disease state under investigation.
OBJECTIVES: The objectives of the study were to develop and validate a comorbidity index for ischemic stroke patients for use in longitudinal studies.
METHODS: A 5-year retrospective review of all Georgia Medicaid claims data from 1990 to 1994 was used to detect first time ischemic stroke patients. Ischemic strokes were defined by three ICD-9-CM code series (433.XX, 434.XX, and 436.XX). Comorbid conditions were measured from all claims submitted within 12 months prior the first ischemic stroke event. Half of the stroke cohort was randomly selected, and multivariate logistic regression was used to derive a mortality stroke-specific weighted-index, controlling for age and gender. The Charlson and stroke-specific indexes were then tested on the second half of the stroke cohort for their ability to predict risk of death.
RESULTS: We identified 3,784 ischemic stroke patients with a mean age of 65 years (range 40 B 102). Of all patients, 40% died within the 3-year follow-up and 73% were women. A more concise index with 7 comorbid disease states was identified. The original Charlson index has 16 comorbidities. The stepwise multiple logistic regression integer weights for the 7 comorbidities were 2 for CHF, dementia, neoplasia, and renal disease, and 6 for metastatic solid tumor, liver diseases, and AIDS. Finally, when tested on the second group, the stroke-specific index showed stepwise increases in the cumulative mortality attributable to comorbid diseases (p log rank ÷ 2 < 0.001), whereas the Charlson index did not.
CONCLUSION: This shorter stroke-specific index allows for the development of more highly discriminant comorbidity models for risk adjustment. 相似文献
OBJECTIVES: The objectives of the study were to develop and validate a comorbidity index for ischemic stroke patients for use in longitudinal studies.
METHODS: A 5-year retrospective review of all Georgia Medicaid claims data from 1990 to 1994 was used to detect first time ischemic stroke patients. Ischemic strokes were defined by three ICD-9-CM code series (433.XX, 434.XX, and 436.XX). Comorbid conditions were measured from all claims submitted within 12 months prior the first ischemic stroke event. Half of the stroke cohort was randomly selected, and multivariate logistic regression was used to derive a mortality stroke-specific weighted-index, controlling for age and gender. The Charlson and stroke-specific indexes were then tested on the second half of the stroke cohort for their ability to predict risk of death.
RESULTS: We identified 3,784 ischemic stroke patients with a mean age of 65 years (range 40 B 102). Of all patients, 40% died within the 3-year follow-up and 73% were women. A more concise index with 7 comorbid disease states was identified. The original Charlson index has 16 comorbidities. The stepwise multiple logistic regression integer weights for the 7 comorbidities were 2 for CHF, dementia, neoplasia, and renal disease, and 6 for metastatic solid tumor, liver diseases, and AIDS. Finally, when tested on the second group, the stroke-specific index showed stepwise increases in the cumulative mortality attributable to comorbid diseases (p log rank ÷ 2 < 0.001), whereas the Charlson index did not.
CONCLUSION: This shorter stroke-specific index allows for the development of more highly discriminant comorbidity models for risk adjustment. 相似文献
143.
Andrew D. Morris Shinchiro Ueda John R. Petrie John MC Connell Henry L. Elliott Richard Donnelly 《Clinical and experimental pharmacology & physiology》1997,24(7):513-518
1. The recognition of the role of insulin resistance in disease states and the recent development of new drugs that modify insulin-dependent metabolism has led to increased use of the euglycaemic hyperinsulinaemic clamp to measure in vivo insulin sensitivity, but several key aspects of the technique are poorly documented in the literature. 2. We have evaluated the reproducibility and intersubject variation of measurements of insulin sensitivity in groups of insulin-sensitive and insulin-resistant subjects and assessed the effects of hand warming on haemodynamic and metabolic responses. 3. Subjects participated in one of two protocols: (i) 18 healthy male volunteers and 18 patients with hypertension and glucose intolerance were clamped on two occasions, 1 week apart with measurements of insulin sensitivity (M) derived after 120 and 180 min of hyperinsulinaemia; and (ii) six healthy volunteers were clamped on one occasion with simultaneous sampling of antecubital and ‘arterialized’ (dorsal hand) venous blood for comparison of plasma glucose concentrations and oxygen saturation and a further six volunteers were clamped on two occasions with and without the use of hand warming. 4. Measurements of M derived after 120 min (M120) and 180 min (M180) of hyperinsulinaemia were reproducible: the coefficients of repeatability (mg/kg per min) of M120 and M180 were 1.0 and 0.9 for volunteers and 1.0 and 1.0 for the patient group, respectively. The intersubject variation in insulin stimulus was high: coefficients of variation for M180 were 22% for volunteers compared with 38% for the patient group. In volunteers compared with the patient group, hand warming significantly increased venous oxygen saturations (95 ± 2 vs 79 ± 18%, respectively) and glucose concentrations (5.2 ± 0.2 vs 4.5 ± 0.4 mmol/L, respectively) and measurements of M were significantly higher using arterialized compared with antecubital venous blood. However, local hand warming was associated with systemic vasodilatation: blood pressure decreased (e.g. 6mmHg diastolic; P < 0.05) with a compensatory increase in heart rate (8 b.p.m.). 5. In conclusion, clamps of 120 and 180 min duration yielded measurements of M that were reproducible. The technique is much more robust when used in the context of a crossover design because of the significant (20–40%) intersubject variation in M, even among apparently homogeneous male volunteers. Hand warming effectively arterializes venous blood and gives significantly higher M values, but induces systemic vasodilatation, which may confound measurements of M. 相似文献
144.
145.
D Gall C Roussel I Susa E D'Angelo P Rossi B Bearzatto MC Galas D Blum S Schurmans SN Schiffmann 《The Journal of neuroscience》2003,23(28):9320-9327
Calcium-binding proteins such as calretinin are abundantly expressed in distinctive patterns in the CNS, but their physiological function remains poorly understood. Calretinin is expressed in cerebellar granule cells, which provide the major excitatory input to Purkinje cells through parallel fibers. Calretinin-deficient mice exhibit dramatic alterations in motor coordination and Purkinje cell firing recorded in vivo through unknown mechanisms. In the present study, we used patch-clamp recording techniques in acute slice preparation to investigate the effect of a null mutation of the calretinin gene on the intrinsic electroresponsiveness of cerebellar granule cells at a mature developmental stage. Calretinin-deficient granule cells exhibit faster action potentials and generate repetitive spike discharge showing an enhanced frequency increase with injected currents. These alterations disappear when 0.15 mm of the exogenous fast-calcium buffer BAPTA is infused in the cytosol to restore the calcium-buffering capacity. A proposed mathematical model demonstrates that the observed alterations of granule cell excitability can be explained by a decreased cytosolic calcium-buffering capacity resulting from the absence of calretinin. This result suggests that calcium-binding proteins modulate intrinsic neuronal excitability and may therefore play a role in information processing in the CNS. 相似文献
146.
Paul S. Collins MD FACS MAJ MC Paul Orecchia MD FACS Edward Gomez MD FACS MAJ MC 《Annals of vascular surgery》1991,5(2):116-120
This study presents a technique to correct kinking or coiling of the internal carotid artery using patch angioplasty following endarterectomy, resection, and anastomoses of the vessel. Since 1984, 579 carotid endarterectomies have been performed with 19 patients (3.3%) having arteriosclerotic carotid bulb and internal carotid artery disease associated with a carotid kink or coil. These have been treated successfully using the technique of resection and patch angioplasty. The indications for surgery included seven patients with transient ischemic attacks (36.8%); seven patients who had suffered a cerebrovascular accident (36.8%); amaurosis fugax in two patients (10.5%); and one patient each with Hollenhorst plaque (5.3%), central retinal artery occlusion (5.3%), and an asymptomatic critical stenosis (5.3%). All patients had successful repair of the vessel using saphenous vein or Dacron patch angioplasty. There were no perioperative strokes or deaths. Follow-up ranged from four months to 58 months (mean 25 months). All vessels are patent with no evidence of stenosis. One patient had an ipsilateral cerebrovascular accident but had no evidence of recurrent carotid disease. Surgical correction of the carotid kink or coil can present a difficult surgical problem, and resection, fixation, or transposition can be complicated. The technique of endarterectomy, resection of the redundant vessel with anastomosis of the back wail, and patch angioplasty has been used effectively and safely in this series of patients.Presented at the Fifteenth Annual Meeting of the Peripheral Vascular Surgery Society, June 2, 1990, Los Angeles, California.The views and opinions expressed in this paper are those of the authors and do not reflect those of the Department of the Army, Department of Defense, or of the Uniformed Services University of the Health Sciences. 相似文献
147.
The authors present two cases of percutaneous cecostomy performed with a modified approach previously described for percutaneous gastrostomy and cholecystostomy. T-fastener devices were used to affix the cecum to the anterior abdominal wall; thus, the potential problem of fecal spillage was prevented. In both cases, adequate fecal drainage was provided without complication. 相似文献
148.
Elongated Styloid Process (Eagle''s Syndrome) Causing Hemicrania 总被引:1,自引:0,他引:1
SYNOPSIS
Hemifacial pain and hemicrania can be caused by an elongated styloid process (Eagle's syndrome). This entity is reviewed historically with six case histories and x–rays presented. The etiology of the symptom complex is unclear, but possible mechanisms such as cranial nerve pressure and carotid sympathetic nerve involvement are discussed. Specific treatment is surgical removal of the tip of the styloid process. 相似文献
Hemifacial pain and hemicrania can be caused by an elongated styloid process (Eagle's syndrome). This entity is reviewed historically with six case histories and x–rays presented. The etiology of the symptom complex is unclear, but possible mechanisms such as cranial nerve pressure and carotid sympathetic nerve involvement are discussed. Specific treatment is surgical removal of the tip of the styloid process. 相似文献
149.
White cells in fresh-frozen plasma: evaluation of a new white cell- reduction filter 总被引:1,自引:0,他引:1
BACKGROUND: Fresh-frozen plasma (FFP) has generally been regarded as an acellular component. Recently, viable lymphocytes have been detected in this component and the question of irradiation of FFP for certain patients has been raised. Whether the numbers of white cells (WBCs) in FFP are sufficient to require WBC-reduction of acellular components for patients receiving WBC-reduced cellular components has not been determined. WBC numbers in FFP were examined, and the performance of a new commercial WBC-reduction filter for FFP was assessed. STUDY DESIGN AND METHODS: WBC numbers in plasma processed for use as FFP and in thawed FFP were counted before and after WBC-reduction filtration by the use of flow cytometry Fast and slow filtration was used to simulate laboratory and bedside filtration, respectively. Three different methods for plasma harvesting (soft-spin, hard-spin, and second-spin methods) were assessed. The filter capacity was also examined. RESULTS: The numbers of WBCs in plasma covered a three-log10 range (soft-spin method, 0.04-3.6 × 10(6); hard-spin method, 0.47-45.4 × 10(6); second- spin method, 0.4–37.2 × 10(6)). For the hard-spin and second-spin methods which produced the greatest plasma yields, 92 percent and 85.7 percent of bags, respectively, had counts>1 × 10(6) and 43 percent (hard-spin method) and 45.7 percent (second-spin method) had counts>5 × 10(6). There was no significant difference between the counts obtained in plasma and thawed FFP. The filter reduced WBC numbers to <1 × 10(5) in all but 3 of 49 bags. In the remaining three, there were <2 × 10(5) WBCs. Five bags of plasma could be processed effectively through each filter. CONCLUSION: FFP may contain WBC numbers above the threshold at which the use of WBC-reduction filters for cellular components in some patients is necessary. Confirmation of these findings and similar investigations on plasma prepared by other methods may help in defining a role for the use of WBC-reduction filters for FFP 相似文献
150.
目的:虽然前交叉韧带的重建手术已趋成熟,但重建术后韧带稳定性的量化评估仍缺乏一种有效的方法。探讨KT1000/KT2000关节测量仪在膝关节前交叉韧带损伤中的诊断价值以及在韧带重建术后移植物稳定性评估中的应用价值。方法:选择2006-01/2007-01于上海交通大学附属第六人民医院行关节镜下重建手术的膝关节前交叉韧带完全损伤患者80例,对治疗方案均知情同意。①术前利用KT1000/KT2000关节测量仪进行膝关节稳定性的测量,并与抽屉试验、Lachman试验、轴移试验及MRI影像学等检查方法进行对比,验证其敏感度。②分别在术后3个月、6个月、1年以及1年以上利用KT1000/KT2000关节测量仪进行随访测量,采用国际膝关节文献委员会评分对测量结果进行前交叉韧带的稳定性评估,评估标准:等级A为韧带紧张度良好;等级B为韧带紧张度接近正常;等级C为韧带紧张度异常;等级D为韧带紧张度严重异常。结果:80例前交叉韧带完全损伤患者全部进入结果分析。①KT1000测量仪在诊断前交叉韧带损伤时较前抽屉试验及轴移试验敏感率高(P=0.001,0.037),而与Lachman试验及MRI影像学检查敏感率差异无显著性意义(P=0.807,0.598)。②随访结果:术后3个月随访到80例患者,A级68例,B级12例;术后6个月随访到76例患者,A级55例,B级19例,C级1例;术后1年随访到70例患者,A级48例,B级20例;C级2例;术后1年以上随访到68例患者,A级42例,B级22例,C级4例。结论:KT1000/KT2000关节测量仪测量膝关节稳定性的敏感度较高,不仅可应用于膝关节前交叉韧带损伤的临床诊断,还可以评价手术效果,对前交叉韧带重建术后评估移植物稳定性提供了一个量化依据。 相似文献