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71.
Predictive testing for BRCA1 and 2 mutations: a male contribution.   总被引:1,自引:0,他引:1  
BACKGROUND: Management strategies for women carrying BRCA1 and 2 mutations are becoming clearer and predictive testing for a known family mutation is commonly undertaken. Implications for men are not as clear and they participate less frequently. PATIENTS AND METHODS: Twenty-six men from 10 extended families underwent predictive testing. Their motivation, reaction and outcome were studied. Subjects had appropriate pre- and post-test counselling. Informed consent was obtained before predictive testing for known deleterious mutations. DNA analysis followed standard procedures. RESULTS: Eighteen tested positive and eight negative. Four had adverse psychological reactions and three reneged on their commitments to impart results. The spouse of another man had an adverse psychological reaction to the disclosure of his positive result. Two, already suffering from prostate cancer, were phenocopies and paternal lineage transmission was unexpectedly determined in another. Risk was removed from 33 offspring and confirmed for 56. CONCLUSIONS: Complex themes associated with genetic testing are confirmed and the spectrum extended. Men appear to understand the importance of participating in this process. Methods of avoiding adverse reactions merit further study along with other aspects of the process.  相似文献   
72.
To assess whether the semiquantitative peripheral blood Epstein-Barr virus (EBV) polymerase chain reaction (PCR) test correlates with post-transplant lymphoproliferative disorder (LPD), we compiled the results of the test done over a 3-year period ending July 1997. Six hundred seventy-six tests were done on 185 patients. Four hundred-thirty tests (63%) were negative, 167 (25%) were weak positive, 67 (10%) were moderate positive, and 12 (2%) were strong positive. Twelve of the patients developed a lymphoproliferative disorder (LPD) during this time. The EBV PCR tests proximate to the diagnosis of LPD in the 12 patients with EBV-positive LPD were 6 strong positive, 5 moderate positive, 1 weak positive. No patient with LPD had a negative result at diagnosis. Stated another way, 6/12 (50%) of strong-positive PCR tests, 5/67 (7%) moderate-positive tests, and 1/167 (.6%) of weak-positive tests correlated with LPD. Serologic evaluation for EBV done on 7 patients at the time of LPD showed low serologic responses in 5 of the 7 patients. The EBV PCR temporally associated with the serology indicated moderate to large viral burdens. In each patient evaluated serially, the EBV PCR test rose before the diagnosis of LPD and fell with treatment for the disorder. In conclusion, the EBV PCR test may be used as an adjunct to the diagnosis of patients with LPD and may be used to monitor response to therapy for the disorder. Received August 26, 1997; accepted January 13, 1998.  相似文献   
73.
Bailey SH  Shapiro SB  Mone MC  Saffle JR  Morris SE  Barton RG 《American journal of surgery》2000,180(6):517-21; discussion 521-2
BACKGROUND: Current standard of care dictates that central venous catheter (CVC) insertion should be followed by an immediate chest radiograph to confirm appropriate position and rule out complications. We hypothesized that a subset of monitored intensive care unit patients exists that is at low risk for complications and might safely have radiographic evaluation of line placement deferred until the next scheduled radiograph. METHODS: Data regarding patient and procedural characteristics were obtained prospectively for 184 CVC placed between March 1, 1998, and June 30, 1999. Retrospective data regarding complications were obtained by chart review for an additional 174 CVC placed during the study period but for which data sheets were not completed. All procedures were followed by chest radiography. RESULTS: We documented a complication rate of 9% with the vast majority (25 of 31, 81%) of complications consisting of incorrect positioning. The number of needle passes was greater in the group suffering pneumothorax and arterial puncture than the uncomplicated group (5.6 versus 1.9, P = 0.008). "Straightforward" operator gestalt (P = 0.04) and number of needle passes <3 (P = 0.03) were factors correlating with the absence of complications. These factors had negative predictive values of 94% and 96%, respectively. CONCLUSION: Placement of CVC is safe in experienced hands. In monitored intensive care unit patients who undergo a "straightforward" procedure with <3 needle passes, chest radiograph can be safely deferred until the next scheduled examination.  相似文献   
74.
Improving the quality of care for patients with chronic illness has become a high priority. Implementing training programs in disease management (DM) so the next generation of physicians can manage chronic illness more effectively is challenging. Residency training programs have no specific mandate to implement DM training. Additional barriers at the training facility include: 1) lack of a population-based perspective for service delivery; 2) weak support for self-management of illness; 3) incomplete implementation due to physician resistance or inertia; and 4) few incentives to change practices and behaviors. In order to overcome these barriers, training programs must take the initiative to implement DM training that addresses each of these issues. We report the implementation of a chronic illness management curriculum based on the Improving Chronic Illness Care (ICIC) Model. Features of this process included both patient care and learner objectives. These were: development of a multidisciplinary diabetes DM team; development of a patient registry; development of diabetes teaching clinics in the family practice center (nutrition, general management classes, and one-on-one teaching); development of a group visit model; and training the residents in the elements of the ICIC Model, ie, the community, the health system, self-management support, delivery system design, decision support, and clinical information systems. Barriers to implementing these curricular changes were: the development of a patient registry; buy-in from faculty, residents, clinic leadership, staff, and patients for the chronic care model; the ability to bill for services and maintain clinical productivity; and support from the health system key stakeholders for sustainability. Unique features of each training site will dictate differences in emphasis and structure; however, the core principles of the ICIC Model in enhancing self-management may be generalized to all sites.  相似文献   
75.
Trezies AJ  Davis TR  Barton NJ 《Injury》2000,31(8):605-607
The results of a consecutive series of bone-grafting procedures for non-union of scaphoid fractures were assessed in order to investigate whether the patient's age or the delay between acute fracture and bone-graft surgery influenced the outcome. One hundred and thirty-four patients with a mean follow up of 2.6 years from bone-graft surgery for scaphoid fracture non-union were assessed for post-operative pain and radiographic evidence of union. No association was found between the union rate following surgery and either the patients' ages or the interval between the original injury and subsequent non-union surgery.  相似文献   
76.
OBJECTIVES: To test the hypothesis that meningococcal septicemia-related pulmonary edema is associated with a systemic abnormality of epithelial sodium and chloride transport and to investigate an association with hormones regulating Na transport. DESIGN: Prospective observational study. SETTING: The 24-bed pediatric intensive care unit and pediatric wards of Royal Liverpool Children's Hospital. PATIENTS: Consecutive children admitted to the pediatric intensive care unit and pediatric wards with a diagnosis of meningococcal septicemia and children (controls) with noninfectious critical illness receiving ventilatory support in the pediatric intensive care unit. MEASUREMENTS AND MAIN RESULTS: We measured sweat and saliva electrolytes, renal electrolyte excretion, nasal potential difference, and aldosterone, thyroxine, and cortisol levels. Pulmonary edema was diagnosed by chest radiography and its severity quantified by calculation of ventilation index at admission and duration of mechanical ventilation. We recruited 17 patients with severe meningococcal septicemia (nine patients with pulmonary edema), 14 patients with mild meningococcal septicemia, and 20 controls. Sweat and saliva Na and Cl concentrations and renal Na excretion were significantly (p < .05) higher in patients with pulmonary edema compared with controls. Nasal potential difference and amiloride response in patients with pulmonary edema were not significantly different to controls, but response to a low Cl solution was reduced in the nasal airway of patients with pulmonary edema (p < .05). Sweat and saliva chloride concentrations correlated significantly and better with ventilation index and duration of ventilation than sodium concentrations. Aldosterone, thyroxine, and cortisol levels were not significantly different between groups. CONCLUSIONS: We have confirmed that meningococcal septicemia-related pulmonary edema is associated with reduced systemic sodium and chloride transport. Features of reduced Cl transport were most closely associated with markers of respiratory compromise, and this was supported by the reduced chloride channel function detected on nasal potential difference measurement.  相似文献   
77.
Chemotherapy-induced ovarian failure: manifestations and management.   总被引:8,自引:0,他引:8  
Thanks to improvements in treatment regimens, more and more patients are now surviving cancer. However, cancer survivors are faced with the serious long-term effects of the different modalities of cancer treatments. One of these adverse effects is chemotherapy-induced irreversible damage to the ovarian tissues, which leads to premature ovarian failure and its resulting consequences such as hot flashes, osteoporosis, sexual dysfunction and the risk of infertility. Chemotherapy-induced ovarian failure (or chemotherapy-induced premature menopause) affects the quality of life of female cancer survivors. Although there is no clear definition of chemotherapy-induced ovarian failure, irreversible amenorrhoea lasting for several months (>12 months) following chemotherapy and a follicle stimulating hormone level of > or = 30 MIU/mL in the presence of a negative pregnancy test seems to be an appropriate characterisation. Different chemotherapy agents, alkylating cytotoxics in particular, have the potential to cause progressive and irreversible damage to the ovaries. The result of this damage is a state of premature ovarian failure, with progressive declining of estrogen levels, decreasing bone mass and an increased risk of fractures. Historically, hormonal replacement therapy (HRT) has been used to treat menopausal problems in the general population, but concerns about the potential of estrogen to increase the risk of breast cancer in women at high-risk or increase the risk of recurrence in cancer survivors, have forced physicians to utilise alternative treatments. This review discusses some of the newer therapies that are now available to provide appropriate symptom control, avoid complications such as fractures and possibly prevent infertility by making the ovarian epithelium less susceptible to cytotoxic agents.  相似文献   
78.
PURPOSE: To evaluate the toxicity, antileukemic activity, and pharmacology of raltitrexed administered weekly for 3 weeks to patients with refractory or recurrent leukemia. EXPERIMENTAL DESIGN: Raltitrexed was administered as a 15-minute infusion for 3 consecutive weeks every 5 weeks, at doses ranging from 1.3 to 2.8 mg/m(2). The first course was used to determine the dose-limiting toxicities and maximum tolerated dose. Correlative studies included an assessment of raltitrexed pharmacokinetics and measurement of plasma 2'-deoxyuridine concentrations, a surrogate measure of thymidylate synthase inhibition. RESULTS: Twenty-one children (18 evaluable) with refractory leukemia received 25 courses of raltitrexed. The dose-limiting toxicity was reversible elevation in liver transaminases at the 2.8-mg/m(2) dose level and the maximum tolerated dose was 2.1 mg/m(2) per dose. Pharmacokinetics were best characterized by a two-compartment model with a clearance of 139 mL/min/m(2) (8.3 L/h/m(2)), a 2.4-L volume of distribution, an initial half-life (t(1/2alpha)) of 6 minutes, and a terminal half-life (t(1/2beta)) of 45 minutes. There were three objective responses. CONCLUSIONS: Raltitrexed was well tolerated when administered as a single agent to children with recurrent or refractory leukemia. We observed preliminary evidence of antileukemia activity using this weekly dosing schedule and these observations support further evaluation of raltitrexed in this population.  相似文献   
79.
Polymorphisms in XPD exons 10 and 23 and bladder cancer risk.   总被引:3,自引:0,他引:3  
INTRODUCTION: The nucleotide excision repair gene, xeroderma pigmentosum complementation group D (XPD), has been hypothesized to have a role in cancer risk, but results from prior molecular epidemiologic studies and genotype-phenotype analyses are conflicting. MATERIALS AND METHODS: We examined the frequency of the XPD Asp312Asn polymorphism in exon 10 and the XPD Lys751Gln polymorphism in exon 23 in 505 incident bladder cancer cases and 486 healthy controls. RESULTS: Overall, the XPD exon 10 and 23 genotypes were not associated with bladder cancer risk, after adjusting for age, sex, ethnicity, and smoking status. A gender-specific role was evident that showed an increased risk for women, but not for men, associated with the variant genotypes for both exons. For example, when the exon 23 variant allele genotypes were combined (Lys/Gln + Gln/Gln), there was an increased bladder cancer risk in women [odds ratio (OR), 1.69; 95% confidence interval (95% CI), 1.12-2.58] but not in men (OR, 0.99; 95% CI, 0.79-1.24; P(interaction) = 0.041; OR, 1.62; 95% CI, 1.02-2.58). There was also a gene-smoking interaction that showed the variant alleles for either exon or the combination of both increase the risk of bladder cancer for light and heavy smokers. For exon 23 (P(interaction) = 0.057; OR, 1.21; 95% CI, 0.99-1.47), heavy smokers (> or = 20 pack-years) who carried the exon 23 variant allele genotypes had an OR of 4.13 (95% CI, 2.53-6.73), whereas heavy smokers with the wild-type genotypes were at lower risk (OR, 3.55; 95% CI, 2.19-5.75). Moderate smokers (1-19 pack-years) with the variant allele genotypes had an OR of 1.54 (95% CI, 0.94-2.53), whereas moderate smokers with the wild-type genotypes had an OR of 1.12 (95% CI, 0.63-1.98). CONCLUSIONS: Although we did not observe main effects associated with the XPD genotypes, these results do suggest the variant allele genotypes were associated with increased bladder cancer risk in women and smokers with statistically significant interactions in the exon 23 polymorphism. Although there is biological plausibility, these novel findings for gender and smoking should be interpreted with caution upon confirmation in larger studies.  相似文献   
80.
PURPOSE: To determine the antileukemic activity of weekly oral aminopterin in patients with refractory acute leukemia; to describe the pharmacodynamic properties of aminopterin; and to contrast the intracellular metabolism of aminopterin and methotrexate by patients' blasts in vitro. EXPERIMENTAL DESIGN: Forty-six patients were enrolled in three strata: children with acute lymphoblastic leukemia (ALL), adults with ALL, and patients with acute myeloid leukemia (AML). Aminopterin was given weekly, in two doses of 2 mg/m(2), 12 hours apart. Limited sampling pharmacokinetic analysis was done during the first week of therapy. Accumulation of [(3)H]aminopterin and [(3)H]methotrexate by leukemic blasts was studied in vitro. RESULTS: Six of 22 children with ALL (27%; 95% confidence interval, 8-47%) had clinically significant responses. None of those with AML and only two of 11 adults with ALL had responses meeting protocol definitions, although peripheral blast counts tended to decrease with therapy in all groups. Mucosal toxicity was minimal, even with limited use of leucovorin rescue. Complete bioavailability of aminopterin was confirmed, with a mean area under the curve of 0.52 +/- 0.03 micromol hour/L after oral dosing. No relationship between aminopterin pharmacokinetics and response was seen. In vitro, aminopterin showed more consistent metabolism by leukemic blasts to polyglutamates than methotrexate. Lineage-specific differences in the pattern of intracellular antifolylpolyglutamates were observed. CONCLUSIONS: Weekly oral aminopterin has significant activity among children with refractory ALL. With greater cellular accumulation and metabolism, more reliable bioavailability than methotrexate, and tolerable toxicity at this dose and schedule, aminopterin deserves further study as a potent alternative to methotrexate.  相似文献   
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