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71.
Published data is controversial as to the ability of preoperative localization studies (PLS) to enhance the outcome of initial cervical exploration in patients with primary hyperparathyroidism (PHPT). One surgeon's experience was reviewed to compare surgical success, operative time, and morbidity of initial cervical exploration for PHPT in patients who had undergone PLS versus those who had not. From August 1991 to September 1997, 95 patients who had not undergone prior central cervical exploration presented for surgical management of PHPT. Sixty-seven patients underwent initial cervical exploration without any PLS having been performed (Group A). Twenty-eight patients underwent PLS, either alone or in combination, before surgical intervention (Group B). Analysis of intergroup variability was conducted upon the data available using a two-tailed t test for independent samples. In addition, the sensitivities and positive predictive values of the PLS were calculated using study reports and operative and histologic findings. There was no statistically significant difference in surgical success between those patients who had PLS and those that did not undergo PLS. Sixty-four of 67 patients (95.5%) not having PLS were cured with initial surgery, while 27 of 28 patients (96.4%) who had PLS were surgically cured. Mean postoperative calcium and intact parathormone levels were similar between the two groups, and the mean operative time did not differ. Permanent hypocalcemia occurred in one patient, and five patients had transient hoarseness. Thirty-six total PLS were obtained at an average cost of $752.68/patient, and seven patients underwent multiple tests. Overall, sestamibi scan had the highest positive predictive value (81%). For adenomatous disease alone, sestamibi scan was the most sensitive (83%). Our study shows that for matched groups limited to age, sex, and clinical diagnosis, the use of PLS did not shorten operative time, decrease complication frequency, nor alter the success of the operation as measured by postoperative calcium and parathormone levels. Therefore, routine use of preoperative localization studies before initial cervical exploration for PHPT cannot be recommended.  相似文献   
72.
The aim of this cross-sectional study which took place in a hypertension clinic at a district general hospital in Denmark was to make a pragmatic definition of white coat hypertension. A total of 420 patients were referred consecutively from general practice with newly diagnosed untreated essential hypertension and 146 normal subjects were drawn at random from the Danish national register. The following measurements were taken: office blood pressure; 24-h ambulatory blood pressure (BP) monitoring; echocardiography with determination of left ventricular mass index and relative wall thickness; and early morning urine albumin/creatinine ratios. Four different cut-off levels were studied. An ambulatory daytime BP of 135.6/90.4 mm Hg was found to correspond to an office BP of 140/90 mm Hg in normal controls; used as a cut-off level in patients with newly diagnosed hypertension it separated 19% as white coat hypertensives. The end-organ involvement of these white coat hypertensives differed significantly from those with established hypertension but not from the normal controls. Lower cut-off levels were less efficient in this respect, as was the case when the systolic BP was not taken into account. In conclusion a pragmatic definition of white coat hypertension should--apart from well-established hypertensive office measurements--include a cut-off level close to 135/90 mm Hg ambulatory daytime BP.  相似文献   
73.
This study will evaluate the safety and efficacy of allogenic donor lymphocyte infusions in patients who have relapsed hematologic malignancies after allogeneic bone marrow transplantation (BMT). Donor lymphocyte transfusions have resulted in the cure of some patients with relapsed leukemia or lymphoproliferative disorder after allogeneic BMT, but has been complicated by the development of graft versus host disease (GvHD). We hypothesize that a retroviral vector containing the Herpes simplex thymidine kinase (HStk) gene will allow for retention of the anti-leukemia response of transfused donor lymphocytes while allowing for the adverse effects of GVHD to be mitigated. Patients with relapsed hematologic malignancies after allogeneic BMT will be infused with ex vivo gene modified donor lymphocytes. The Herpes Simplex thymidine kinase (HStk) gene will be transduced into the cells ex vivo using LTKOSN. 1 vector supernate. Insertion of the HStk gene into lymphocytes confers a sensitivity to the anti-herpes drug ganciclovir (GCV). This selective destruction of donor lymphocytes in situ will be used to abrogate the effect of graft versus host disease, if it develops.  相似文献   
74.
LA Smith  DE Barker  CW Chase  LB Somberg  WB Brock  RP Burns 《Canadian Metallurgical Quarterly》1997,63(12):1102-7; discussion 1107-8
The purpose of this review is to present a 4-year experience with the vacuum pack technique of temporary abdominal closure. From April 1992 to December 1996, 171 vacuum packs were performed on 93 patients. Eighty-seven vacuum packs were performed on 38 general surgical patients, and 84 vacuum packs were performed on 55 trauma patients. Overall hospital mortality was 32 per cent. Methods of achieving permanent wound closure varied in 73 patients. Four patients (4.3%) developed enterocutaneous fistulae; four patients developed intra-abdominal abscesses (4.3%). There were no eviscerations. Management of the complicated intra-abdominal process is discussed: 1) the decision to manage the abdomen in an open fashion; 2) which method of temporary closure to use; 3) subsequent explorations; 4) when the abdomen should be closed; 5) which type of closure to use; and 6) when the abdominal wall should be revised (herniorrhaphy). The vacuum pack is the method of choice for open abdomen management and temporary abdominal closure at our institution. With careful subsequent management, good patient outcome can be achieved.  相似文献   
75.
This article reviews the empirical literature on psychosocial, psychopharmacological, and adjunctive treatments for children between the ages of 6 and 12 with internalizing disorders. The aim of this review was to identify interventions that have potential to prevent substance use disorders in adolescence by treating internalizing disorders in childhood. Results suggest that a variety of behavioral, cognitive-behavioral, and pharmacological interventions are effective in reducing symptoms of childhood depression, phobias, and anxiety disorders. None of the studies reviewed included substance abuse outcomes. Thus, little can be said about the relationship between early treatment and the prevention of later substance use. The importance of evaluating the generalizability of research-supported interventions to community settings is highlighted and recommendations for future research are offered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
76.
PURPOSE: We designed and conducted a randomized single-institution trial comparing two common prophylactic platelet transfusion thresholds in patients undergoing induction therapy for acute leukemia. PATIENTS AND METHODS: Seventy-eight patients undergoing induction therapy for acute leukemia were randomized to receive prophylactic apheresis platelet concentrates when the platelet count was either < or = 10,000/microL or < or = 20,000/microL. RESULTS: There was no significant difference in the total number of bleeding episodes per patient with a median of four in the < or = 10,000/microL arm and two in the < or = 20,000/microL arm (25th to 75th percentiles of 2, 7 and 1, 5, respectively; P = .12). Patients randomized to the < or = 10,000/microL arm received more platelet transfusions for bleeding [one (0, 2) v zero (0, 0); P = .0003]. In contrast, patients on the < or = 20,000/microL arm received more platelet transfusions for prophylactic indications [10 (5, 14) v six (3, 8); P = 0.001], as would be expected, but less for bleeding. Nevertheless, the total number of platelet transfusions given to patients on the < or = 20,000/microL arm was higher and nearly significant [11 (6, 15) v seven (5, 11); P = .07]. There were no statistically significant differences between the groups with regard to RBC transfusion requirements, febrile days, days hospitalized, days thrombocytopenic, need for HLA-matched platelets, remission rate, or death during induction chemotherapy. No patient in either group died from hemorrhage or underwent major surgery for bleeding complications. CONCLUSION: Giving prophylactic platelets at a threshold of < or = 10,000/microL compared with < or = 20,000/microL can decrease the total utilization of platelets with only a small adverse effect on bleeding, and no statistically significant effect on morbidity.  相似文献   
77.
This study examines the influence of six patient characteristics (age, race, socioeconomic status, comorbidities, mobility and presentational style) and two physician characteristics (medical specialty and years of clinical experience) on physicians' clinical decision making behaviour in the evaluation treatment of an unknown and known breast cancer. Physicians' variability and certainty associated with diagnostic and treatment behaviour were also examined. Separate analyses explored the influence of these non-medical factors on physicians' cognitive processes. Using a fractional factorial design, 128 practising physicians were shown two videotaped scenarios and asked about possible diagnoses and medical recommendations. Results showed that physicians displayed considerable variability in response to several patient-based factors. Physician characteristics also emerged as important predictors of clinical behaviour, thus confirming the complexity of the medical decision-making process.  相似文献   
78.
OBJECTIVE: To characterize Seprafilm bioresorbable membrane and assess its efficacy and safety in reducing adhesions. DESIGN: In vitro and animal studies designed to provide precise control of tissue trauma and closely approximate clinically relevant conditions in abdominal surgery. SETTING: Experimental laboratories, USA. SUBJECTS: Experimental animals, principally rats and rabbits. INTERVENTIONS: The rat cecal abrasion or sidewall injury model evaluated the efficacy of seprafilm in the presence of blood and irrigation solutions, in multiple layers, under ischemic conditions, and in adhesion reformation. A rabbit anastomosis model tested the effect of the membrane on wound healing, and a series of challenge tests determined its toxicology, immunogenicity, and biocompatibility. MAIN OUTCOME MEASURES: Incidence and severity of adhesions; mutagenicity; pyrogenicity; irritation effects; systemic toxicity. RESULTS: Seprafilm significantly reduced the number of cecal adhesions (p < 0.001) and the number of animals with severe adhesions (p < 0.001) when compared with nontreated controls, even in the presence of bleeding. The membrane also significantly decreased the number of animals with any adhesions (p < 0.001). Seprafilm maintains efficacy when used with excess irrigation solutions, when layered, and under ischemic conditions. Among rats tested for adhesion reformation, the treated group had a significantly larger proportion of adhesion-free animals than the untreated group, 72% versus 28%, (p = 0.007). Seprafilm did not impair wound healing in anastomosis and is nontoxic, nonmutagenic, nonimmunogenic, nonpyrogenic, nonirritating, and biocompatible. CONCLUSION: Preclinical studies have shown that Seprafilm is safe and effective in reducing postsurgical adhesions. Seprafilm meets the requirements of an ideal barrier and can be a useful adjuvant in abdominal and pelvic surgery.  相似文献   
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