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991.
992.
BACKGROUND/OBJECTIVE: To describe an apparent relationship between smoking and the neuropathic pain experience in people with spinal cord injury (SCI). METHOD: Case Reports. PARTICIPANTS/METHODS: Two individuals treated at a rehabilitation center. The first was a 38-year-old white man with a T1 2 SCI, American Spinal Injury Association (ASIA) impairment scale (AIS) A, secondary to motor vehicle crash. Duration of injury was 14 years. He reported burning pain in his legs, and has smoked 1/2 pack per day for the last 15 years. The second was a 55-year-old African American man with a T6 SCI, AIS A, secondary to gunshot wound. Duration of injury was 22 years. He was a 40-year 1/2 to 1 pack per day smoker, who, after injury, consistently experienced burning, radicular pain, rated 7/10, around the level of the injury. SUMMARY: The first subject rated his pain as 4/10 when not smoking and 7/10 when smoking. The pain subsided 30 minutes after smoking was discontinued. He noted an immediate increase in neuropathic pain when smoking. The second subject quit smoking for 1 month and immediately noted that the pain disappeared, rating it 0/10. After he resumed smoking, his radicular pain was 8.5/10 in the morning and 5/10 in afternoon. CONCLUSIONS: No similar reports have been published, based on a MEDLINE search. Nicotinic receptors have been implicated in pain perception. It is unclear to what extent these 2 cases generalize to the SCI population. We plan to explore this via survey and experimental research. Smoking cessation may have a dual benefit of increased health and decreased neuropathic pain.  相似文献   
993.
994.
OBJECTIVES: Mitral repair in active infective endocarditis still remains controversial. Several studies demonstrate the feasibility of mitral repair in infective endocarditis; however, superiority of repair has never been shown. The aim of the investigation was to compare valve repair and valve replacement in respect to the extent of destruction and to analyze survival, recurrent endocarditis, and reoperation (event-free survival). METHODS: Sixty-eight consecutive patients underwent surgical intervention for mitral endocarditis. Thirty-four (50%) patients had valve repair, and 34 (50%) patients had valve replacement. Leaflet destruction involving at least one mitral leaflet was present in 15 (44.1%) patients of the repair group and 11 (32.4%) patients of the replacement group. Repair of the mitral annulus with pericardium was performed in 4 (11.8%) patients in the repair group and 3 (8.8%) patients in the replacement group. Patients in both groups were similar concerning the progression of valvular destructions and comorbidities. RESULTS: Hospital mortality was 11.8% (8 patients). No significant differences were found in all baseline parameters, with the exception of a higher incidence of previous septic embolism and sepsis in the repair group. Actuarial event-free survival at 1 year was 88.2% in the repair group compared with 67.7% in the replacement group, and 5-year event-free survival was 80.4% in the repair group and 54.6% in the replacement group (P = .015). Mitral valve repair remained the superior treatment regarding event-free survival in the multivariate analysis (hazard ratio, 0.33; 95% confidence interval, 0.12-0.93; P = .02). CONCLUSIONS: Mitral valve repair offers excellent early and late results and is the preferable treatment option in the surgical therapy of native infective endocarditis.  相似文献   
995.
996.
The purpose of the present study was to find an efficient and reliable chemically assisted procedure for enucleation related to the handmade cloning (HMC) technique. After in vitro maturation oocytes were incubated in 0.5 microg mL(-1) demecolcine for 2 h. Subsequently, zonae pellucidae were digested with pronase, and one-third of the cytoplasm connected to an extrusion cone was removed by hand using a microblade. The remaining two-thirds were used as recipients for HMC, and reconstructed and activated embryos were cultured for 7 days. The time-dependent manner of the development of extrusion cones, the efficiency (oriented bisection per oocyte; 94%), reliability (success per attempted enucleation; 98%), and the blastocyst per reconstructed embryo rates (48%) were measured. Ultrastructural analyses demonstrated that demecolcine treatment resulted in disoriented and haphazardly orientated microtubules. The general ultrastructure of the oocyte organelles, however, appeared to be unaltered by the treatments. Considering that no oocyte selection based on polar body presence was performed, this system seems to be more efficient and reliable than any other enucleation method. Moreover, expensive equipment (inverted fluorescence microscope) and a potentially harmful step (staining and ultraviolet illumination) can be eliminated from the HMC procedure without compromising the high in vitro efficiency.  相似文献   
997.
The psychiatric and psychosocial evaluation of the heart transplant candidate can identify particular predictors for postoperative problems. These factors, as identified during the comprehensive evaluation phase, provide an assessment of the candidate in context of the proposed transplantation protocol. Previous issues with compliance, substance abuse, and psychosis are clear indictors of postoperative problems. The prolonged waiting list time provides an additional period to evaluate and provide support to patients having a terminal disease who need a heart transplant, and are undergoing prolonged hospitalization. Following transplantation, the patient is faced with additional challenges of a new self-image, multiple concerns, anxiety, and depression. Ultimately, the success of the heart transplantation remains dependent upon the recipient's ability to cope psychologically and comply with the medication regimen. The limited resource of donor hearts and the high emotional and financial cost of heart transplantation lead to an exhaustive effort to select those patients who will benefit from the improved physical health the heart transplant confers.  相似文献   
998.
56 year-old male presented to the University of Mississippi Medical Center emergency department (ED) with complaints of progressive shortness of breath, productive cough, fever, and malaise. His past medical history was significant for hypertension as well as a 60 pack-year history of smoking. Upon arrival to the ED he had a temperature of 103.6 degrees F, blood pressure of 80/40 mm Hg, a pulse of 110 beats per minute, respirations of 28 per minute, and an oxygen saturation of 50% on room air. He appeared to be in significant respiratory distress. Lung examination revealed diffuse bilateral rhonchi and wheezes in all lung fields. He was emergently intubated. Chest radiograph demonstrated a miliary pattern scattered throughout all lung fields in addition to parenchymal opacities. A complete blood count revealed a white blood cell count of 33,500 10(3)/microL, hematocrit of 37%, and platelets of 906,000 10(3)/uL. Blood urea nitrogen and creatinine were 27 mg/dL and 1.0 mg/dL, respectively. Initial ABG on 100% oxygen showed pH 7.15, pCO2 82 mm Hg, and pO2 62 mm Hg. Troponin I was negative. An electrocardiogram demonstrated sinus tachycardia. Blood and urine cultures were obtained.  相似文献   
999.
Randomized trials stopped early for benefit: a systematic review   总被引:17,自引:2,他引:15  
Context  Randomized clinical trials (RCTs) that stop earlier than planned because of apparent benefit often receive great attention and affect clinical practice. Their prevalence, the magnitude and plausibility of their treatment effects, and the extent to which they report information about how investigators decided to stop early are, however, unknown. Objective  To evaluate the epidemiology and reporting quality of RCTs involving interventions stopped early for benefit. Data Sources  Systematic review up to November 2004 of MEDLINE, EMBASE, Current Contents, and full-text journal content databases to identify RCTs stopped early for benefit. Study Selection  Randomized clinical trials of any intervention reported as having stopped early because of results favoring the intervention. There were no exclusion criteria. Data Extraction  Twelve reviewers working independently and in duplicate abstracted data on content area and type of intervention tested, reporting of funding, type of end point driving study termination, treatment effect, length of follow-up, estimated sample size and total sample studied, role of a data and safety monitoring board in stopping the study, number of interim analyses planned and conducted, and existence and type of monitoring methods, statistical boundaries, and adjustment procedures for interim analyses and early stopping. Data Synthesis  Of 143 RCTs stopped early for benefit, the majority (92) were published in 5 high-impact medical journals. Typically, these were industry-funded drug trials in cardiology, cancer, and human immunodeficiency virus/AIDS. The proportion of all RCTs published in high-impact journals that were stopped early for benefit increased from 0.5% in 1990-1994 to 1.2% in 2000-2004 (P<.001 for trend). On average, RCTs recruited 63% (SD, 25%) of the planned sample and stopped after a median of 13 (interquartile range [IQR], 3-25) months of follow-up, 1 interim analysis, and when a median of 66 (IQR, 23-195) patients had experienced the end point driving study termination (event). The median risk ratio among truncated RCTs was 0.53 (IQR, 0.28-0.66). One hundred thirty-five (94%) of the 143 RCTs did not report at least 1 of the following: the planned sample size (n = 28), the interim analysis after which the trial was stopped (n = 45), whether a stopping rule informed the decision (n = 48), or an adjusted analysis accounting for interim monitoring and truncation (n = 129). Trials with fewer events yielded greater treatment effects (odds ratio, 28; 95% confidence interval, 11-73). Conclusions  RCTs stopped early for benefit are becoming more common, often fail to adequately report relevant information about the decision to stop early, and show implausibly large treatment effects, particularly when the number of events is small. These findings suggest clinicians should view the results of such trials with skepticism.   相似文献   
1000.
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