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101.
Qualitative research provides understanding of phenomena with a depth and richness that cannot be generated through quantitative approaches. Qualitative methods, however, can often appear difficult, if not confusing. In this article, the authors take the reader through the grounded theory process using Devers's research, Experiencing the Deceased: Reconciling the Extraordinary (1994), a study of after death communication (ADC), to illustrate the use of this particular qualitative method.The authors hope that this article will leave the reader with a better understanding of grounded theory method and stimulate an interest in using it for studying other death-related topics.  相似文献   
102.
103.
PURPOSE: 1) To compare the baseline levels of heat shock and antioxidant protein content in the skeletal muscle of trained and untrained humans and 2) to characterize the exercise-induced stress response of aerobically trained human skeletal muscle to an acute exercise challenge. METHODS: Resting muscle biopsies were obtained from the vastus lateralis muscle of six untrained and six aerobically trained young males. To characterize the stress response of a trained population, the trained subjects also performed a 45-min nondamaging running exercise protocol at an intensity corresponding to 75% of V O2max. Muscle biopsies were obtained from the vastus lateralis muscle at 48 h and 7 d after exercise. RESULTS: Trained subjects displayed significantly higher (P<0.05) resting levels of heat shock protein 60 (HSP60, 25%), alphaB-crystallin (43%), and manganese superoxide (MnSOD, 45%) protein content compared with untrained subjects. Trained subjects also exhibited no significant change (P > 0.05) in resting levels of HSP70 (16%), HSC70 (13%), and total superoxide dismutase (SOD) activity (46%) compared with untrained subjects. Resting HSP27 levels were unaffected by exercise training (P > 0.05). In the trained subjects, exercise failed to induce significant increases (P>0.05)in muscle content of HSP70, HSC70, HSP60, HSP27, alphaB-crystallin, and MnSOD protein content or in the activity of SOD at any time point after exercise. CONCLUSION: This study demonstrates for the first time that trained men display a selective up-regulation of basal heat shock and antioxidant protein content and do not exhibit a stress response to customary running exercise. It is suggested that an increase in these protective systems functions to maintain homeostasis during the stress of exercise by protecting against disruptions to the cytoskeleton/contractile machinery, by maintaining redox balance, and by facilitating mitochondrial biogenesis.  相似文献   
104.
Encouraging results from our previous studies of sentinel lymph node (SLN) mapping in colorectal cancer (CRC) prompted investigation of its feasibility and accuracy during laparoscopic colectomy for early CRC. Between 1996 and 2000, 14 patients with clinically localized colorectal neoplasms underwent colonoscopic tattooing of the primary site and SLN mapping. In each case 0.5 to 1 cm3 of isosulfan blue dye was injected submucosally via the colonoscope. The blue-stained lymphatics were visualized through the laparoscope and followed to the SLN, which was marked with a clip, and laparoscopic colectomy was completed in the routine fashion. All lymph nodes were examined by hematoxylin and eosin (H&E) staining; in addition each SLN was subjected to focused examination by multisectioning and immunohistochemical staining using cytokeratin antibody. In all 14 patients the primary neoplasm and an SLN were identified laparoscopically. An average of 13.5 total lymph nodes and 1.7 SLNs per patient were identified. The SLN correctly reflected the tumor status of the nodal basin in 93 per cent of the cases. In four cases with unexpected lymphatic drainage, the extent of mesenteric resection was altered. In two cases (14%), nodal involvement was micrometastatic, confined to an SLN, and identified only by immunohistochemical staining. Lymphatic mapping caused no complications and added only 10 to 15 minutes to the overall operative time. Comparison of results in this group with results for a matched group of 14 patients undergoing SLN mapping during open colon resection showed that the laparoscopic technique had similar rates of accuracy and success. These preliminary findings indicate that colonoscopic/laparoscopic SLN mapping during laparoscopic colon resection is a feasible and technically simple means of identifying the primary colorectal neoplasm and its SLN. Focused pathologic examination of this node can upstage CRC and thereby may improve selection of patients for adjuvant chemotherapy.  相似文献   
105.
PURPOSE: We assessed the feasibility of a watchful waiting protocol with selective delayed intervention using clinical, prostate specific antigen (PSA) or histological progression as treatment indications for clinically localized prostate cancer. MATERIALS AND METHODS: In this prospective, single arm cohort study patients with favorable clinical parameters (stage T1b to T2b N0M0, Gleason score 7 or less and PSA 15 ng./ml. or less) are conservatively treated with watchful waiting. When a patient meets disease progression criteria, arbitrarily defined by the 3 parameters of the rate of PSA increase, clinical progression or histological upgrade on repeat prostate biopsy, appropriate treatment is implemented. Patients are followed every 3 months for the first 2 years and every 6 months thereafter. Serum PSA measurement and digital rectal examination are done at each visit and repeat prostate biopsy is performed 18 months after study enrollment. RESULTS: Since November 1995, the study has accrued 206 patients with a median followup of 29 months (range 2 to 66). Of these men 137 remain on the surveillance protocol with no disease progression, while 69 were withdrawn from study for various reasons. There was clinical, PSA and histological progression in 16, 15 and 5 cases, respectively. The estimated actuarial probability of remaining on the surveillance protocol was 67% at 2 years and 48% at 4. The probability of remaining progression-free was 81% and 67% at 2 and 4 years, respectively. CONCLUSIONS: A policy of watchful waiting with selectively delayed intervention based on predefined criteria of disease progression is feasible. This strategy offers the benefit of an individualized approach based on the demonstrated risk of clinical or biochemical progression with time and, thus, it may decrease the burden of therapy in patients with indolent disease, while providing definitive therapy for those with biologically active disease.  相似文献   
106.
HYPOTHESIS: Comorbid conditions are associated with the risk of death from coronary artery bypass graft surgery. DESIGN: Prospective cohort study data were collected on patient and disease characteristics and comorbid conditions including hypertension, diabetes, obesity, vascular disease, chronic obstructive pulmonary disease, cancer (excluding nonmelanoma skin cancer), dialysis-dependent renal failure, liver disease, and dementia. Statistical analysis used logistic regression for the calculation of adjusted odds ratios (ORs) and 95% confidence intervals (CIs). SETTING: Regional cardiac surgery database. PATIENTS: A total of 27,239 consecutive patients undergoing isolated coronary artery bypass graft surgery. MAIN OUTCOME MEASURE: In-hospital mortality rate. RESULTS: The prevalence of comorbid conditions was as follows: hypertension, 64.3%; diabetes, 30.1%; obesity, 24.6%; severe obesity, 7.2%; vascular disease, 18.3%; chronic obstructive pulmonary disease, 10.9%; peptic ulcer, 7.5%; cancer, 3.8%; renal failure, 1.5%; liver disease, 0.6%; and dementia, 0.1%. After adjustment for patient and disease characteristics, including age, sex, previous cardiac surgery, priority of surgery, degree of left main coronary stenosis, number of diseased coronary arteries, and left ventricular ejection fraction, the following comorbid conditions were significant predictors of in-hospital mortality: diabetes (OR, 1.19; 95% CI, 1.01-1.40; P =.03), vascular disease (OR, 1.67; 95% CI, 1.41-1.97; P<.001), chronic obstructive pulmonary disease (OR, 1.57; 95% CI, 1.29-1.91; P<.001), peptic ulcer (OR, 1.34; 95% CI, 1.05-1.71; P =.02), and dialysis-dependent renal failure (OR, 3.68; 95% CI, 2.65-5.13; P<.001). There was no significant association between in-hospital mortality and hypertension, obesity or severe obesity, cancer, liver disease, or dementia. CONCLUSION: Even after adjustment for other patient and disease characteristics, comorbid conditions (especially diabetes, vascular disease, chronic obstructive pulmonary disease, peptic ulcer disease, and dialysis-dependent renal failure) are associated with significantly increased risk of death after coronary artery bypass graft surgery.  相似文献   
107.
HYPOTHESIS: The use of mechanical circulatory support (MCS) during repair of traumatic aortic injuries is associated with a decreased incidence of postoperative paraplegia and mortality. DESIGN AND SETTING: Historical cohort study with contemporaneous but nonrandomized controls in a tertiary care hospital from July 1, 1988, through December 31, 1999. PATIENTS AND INTERVENTIONS: Consecutive cases undergoing operation for traumatic aortic injuries. Use of MCS (with or without systemic heparinization) determined by surgeon preference. MAIN OUTCOME MEASURES: Incidence of postoperative paraplegia and mortality. RESULTS: Twenty-two patients underwent repair of traumatic aortic injuries using MCS, resulting in no paraplegia but 4 deaths, 3 of them from cerebral ischemia. Thirteen patients had their traumatic aortic injuries repaired using a "clamp-and-sew" or passive shunt technique with no deaths but paraplegia in 2. Compared with an earlier report from our group from January 1, 1975, through June 30, 1988, the annual incidence of traumatic aortic injuries has decreased, whereas the age of patients and proportion of operations using MCS have increased. A review of the recent literature on traumatic aortic injuries reveals an average postoperative paraplegia incidence of 1% with MCS and 16% without MCS. Overall mortality is similar, but others have also reported cases of cerebral ischemia after aortic repair. CONCLUSIONS: The use of MCS during repair of traumatic aortic injuries is associated with a decreased incidence of postoperative paraplegia. The occasional occurrence of cerebral ischemia deserves further study.  相似文献   
108.
BackgroundRoux-en-Y gastric bypass surgery is the leading surgical treatment of morbid obesity in the United States. The role of preoperative weight loss in gastric bypass surgery remains controversial. We performed a prospective randomized trial to determine whether preoperative weight loss results in better outcomes after laparoscopic gastric bypass.MethodsA total of 100 patients undergoing laparoscopic gastric bypass surgery from May 2004 to October 2005 were randomized preoperatively to either a weight loss group with a 10% weight loss requirement or a group that had no weight loss requirements. The patients were followed prospectively. The variables analyzed included perioperative complications, operative time, postoperative weight loss, and resolution of co-morbidities.ResultsData were available for 26 patients in the weight loss group and 35 in the nonweight loss group. The 2 groups had similar preoperative characteristics, conversion and complication rates, and resolution of co-morbidities. The initial body mass index was 48.7 kg/m2 and 49.3 kg/m2 for the weight loss group and nonweight loss group, respectively (P = NS). The preoperative body mass index was 44.5 kg/m2 and 50.7 kg/m2 for the weight loss group and nonweight loss group, respectively (P = 0.0027). The operative time was 220.2 and 257.6 minutes for the 2 groups (P = 0.0084). The percentage of excess weight loss at 3 and 6 months for the weight loss group and nonweight loss group was 44.1% and 33.1% (P = 0.0267) and 53.9% and 50.9% (P = NS), respectively. The interval to surgery from the initial consultation was 5.4 months and 5.2 months for the 2 groups (P = NS).ConclusionsPreoperative weight loss before laparoscopic Roux-en-Y gastric bypass was associated with a decrease in the operating room time and an improved percentage of excess weight loss in the short term. Preoperative weight loss, however, did not affect the major complication or conversion rates, and its long-term effects were not apparent through this study. Also, preoperative weight loss did not have any bearing on the resolution of co-morbidities.  相似文献   
109.
Introduction We report an isolated pedigree in which a consanguineous couple had twin sons with Dandy–Walker malformation (DWM). The mother is similarly affected with the disorder.Discussion DWM is an abnormality of the central nervous system, which leads to hydrocephalus and is associated with other abnormalities.Conclusion Inheritance of the disorder remains controversial, with the majority perceived to be sporadic cases. This report suggests an autosomal inheritance.  相似文献   
110.
STUDY DESIGN: Patient satisfaction with the cosmetic result of spinal fusion surgery was studied in 42 cases of adolescent idiopathic scoliosis. Neutral or dissatisfied patients were compared with satisfied patients on several physical and psychological characteristics. OBJECTIVES: To determine whether adolescents generally report satisfaction with the postoperative appearance of their back after the correction of severe curves and whether preoperative medical and/or psychological factors distinguish between patients who will report satisfaction with the cosmetic surgical result from those who will report neutrality or dissatisfaction. SUMMARY OF BACKGROUND DATA: Previous reports emphasize the need for medical outcomes research that evaluates both patient satisfaction and technical success. Patient satisfaction with spinal surgery has largely been evaluated in retrospective studies and most consistently related to postoperative cosmesis and degree of curve correction. METHODS: Forty-two adolescents with idiopathic scoliosis without comorbidity, who were 12 years 6 months of age or older, and who did not require both anterior and posterior spinal fusion, were studied preoperatively and postoperatively by physical and psychological measurements. RESULTS: Of patients undergoing surgical correction of severe curves, 73% reported satisfaction with the cosmetic result. Neutral or dissatisfied patients were more likely than satisfied patients to have a lower body mass index (P < 0.05), to be younger in menarcheal status (P < 0.05), and have a King II or King III curve type. Preoperative psychological difficulties (P < 0.05) and unmet expectations regarding the postoperative cosmesis (P < 0.05) were more common among neutral or dissatisfied patients. CONCLUSIONS: Most adolescents with idiopathic scoliosis expressed satisfaction with the cosmetic surgical result. Preoperative physical characteristics, psychological difficulties, and unrealistic expectations regarding postoperative cosmesis are associated with patient neutrality or dissatisfaction.  相似文献   
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