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81.
Trastuzumab-associated cardiotoxicity 总被引:9,自引:0,他引:9
Trastuzumab is a monoclonal antibody used for the treatment of metastatic breast carcinoma in women whose tumors overexpress the HER2 protein. Cardiotoxicity has been reported to occur with trastuzumab when administered alone and in combination with antineoplastic agents, particularly anthracyclines. The risk of cardiotoxicity with trastuzumab has been reported to be 4% with monotherapy and 27% when administered in combination with an anthracycline and cyclophosphamide, but to the author's knowledge severe outcomes, such as death or permanent disability, are uncommon. The majority of reported cardiac effects are mild to moderate, nonspecific, and medically manageable. Signs and symptoms are similar to those observed in patients who develop anthracycline-induced cardiomyopathy and include tachycardia, palpitations, and exertional dyspnea, which may progress to congestive heart failure. The pathogenesis and histologic changes responsible for trastuzumab-associated cardiotoxicity currently are under investigation. Unlike anthracycline-induced toxicity, trastuzumab-associated toxicity usually responds to standard treatment or the discontinuation of trastuzumab, and there is no evidence that the toxicity is dose related. Current methods for the early detection of cardiotoxicity in trastuzumab-treated patients are similar to those used in anthracycline-treated patients. Cardiac function is established at baseline and monitored regularly during treatment by physical examination and measurement of left ventricular ejection fraction. The majority of patients improve with proper treatment, and some are able to continue to receive trastuzumab. 相似文献
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83.
DL DSouza SB Heinze RJ Dowling 《Journal of Medical Imaging and Radiation Oncology》2006,50(3):246-248
Lung cancer is not commonly known to metastasise to the perirenal space, with only five such cases previously published. We present an unusual case of perirenal lung metastases manifesting as diffuse perinephric stranding which to our knowledge has not been described before. 相似文献
84.
BACKGROUND: Studies have shown that the nature and quality of coping may positively or negatively affect health outcome; however, this relationship has not been well studied among patients with gastrointestinal (GI) disorders. OBJECTIVES: The primary objective was to study the effect of different coping strategies on the health outcome of women with GI disorders and how these coping strategies may modify the effects of education, GI disease type, neuroticism, and abuse severity on health outcome. METHODS: We followed 174 patients in a referral GI clinic for 12 months to assess their health status as a derived variable of daily pain, bed disability days, psychological distress, daily dysfunction, number of visits to physicians, and number of surgeries and procedures. We obtained at baseline their GI diagnosis (functional vs. organic), neuroticism score (NEO Personality Inventory), sexual and/or physical abuse history, and scores on two coping questionnaires. Regressions analyses were used to determine the relative effect of the coping measures on health outcome and their modifying effects on education, GI disease type, neuroticism, and abuse severity. RESULTS: A higher score on the Catastrophizing scale and a lower score on the Self-Perceived Ability to Decrease Symptoms scale (Coping Strategies Questionnaire) predicted poor health outcome. Less education, a functional GI diagnosis, a higher neuroticism score, and greater abuse severity also contributed to poor health status. However, the effect of GI disease type and neuroticism on health outcome was significantly reduced by the coping measures. CONCLUSIONS: Maladaptive coping (eg, catastrophizing) and decreased self-perceived ability to decrease symptoms may adversely affect health outcome and may modify the effect of GI disease type and neuroticism on health outcome. 相似文献
85.
Chemotherapy for cancer causes apoptosis that precedes hypoplasia in crypts of the small intestine in humans 总被引:18,自引:0,他引:18
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BACKGROUND AND AIMS: The mechanism of gastrointestinal damage (mucositis) induced by cancer chemotherapy remains uncertain. The aims of this study were to define the time course and mechanism of small intestinal damage following chemotherapy in humans. METHODS: Patients receiving chemotherapy underwent upper gastrointestinal endoscopy (a maximum of two per patient) with duodenal biopsy prior to chemotherapy and again at 1, 3, 5, and 16 days after chemotherapy. Tissue was taken for morphometry, disaccharidase assays, electron microscopy, and for assessment of apoptosis using the Tdt mediated dUTP-biotin nick end labelling (TUNEL) method. Villus area, crypt length, and mitotic index were measured by a microdissection technique. RESULTS: Apoptosis increased sevenfold in intestinal crypts at one day, and villus area, crypt length, mitotic count per crypt, and enterocyte height decreased at three days after chemotherapy. Disaccharidase activities remained unchanged. Electron microscopy showed increased open tight junctions of enterocytes at day 3, consistent with more immature cells. All indices improved by 16 days. CONCLUSION: Small intestinal mucositis is associated with apoptosis in crypts that precedes hypoplastic villous atrophy and loss of enterocyte height. 相似文献
86.
Brandon DL Marshall Thomas Kerr Chris Livingstone Kathy Li Julio SG Montaner Evan Wood 《Harm reduction journal》2008,5(1):35
Aboriginal people experience a disproportionate burden of HIV infection among the adult population in Canada; however, less
is known regarding the prevalence and characteristics of HIV positivity among drug-using and street-involved Aboriginal youth.
We examined HIV seroprevalence and risk factors among a cohort of 529 street-involved youth in Vancouver, Canada. At baseline,
15 (2.8%) were HIV positive, of whom 7 (46.7%) were Aboriginal. Aboriginal ethnicity was a significant correlate of HIV infection
(odds ratio = 2.87, 95%CI: 1.02 – 8.09). Of the HIV positive participants, 2 (28.6%) Aboriginals and 6 (75.0%) non-Aboriginals
reported injection drug use; furthermore, hepatitis C co-infection was significantly less common among Aboriginal participants
(p = 0.041). These findings suggest that factors other than injection drug use may promote HIV transmission among street-involved
Aboriginal youth, and provide further evidence that culturally appropriate and evidence-based interventions for HIV prevention
among Aboriginal young people are urgently required. 相似文献
87.
88.
Recognition and correction of septal abnormalities in rhinoplastic surgery has been a constant evolution aided by the development of an in depth anatomic understanding of the nose and the refinement of techniques based on the pertinent anatomy. Whether the deformity presents a functional, aesthetic, or combined problem, the authors prefer a single stage technique that separates the structural components of the nose, isolating the deformities present, and then reconstructing the components to effect a desirable result in terms of airway and appearance. Although no two nasal surgeries are identical, there are characteristic deformities that are noted to be generally more problematic. We briefly review normal septal anatomy as it pertains to the septorhinoplasty operation and then discuss our approach to specific septal variations that we have found to have a significant impact with regard to achieving satisfactory functional and aesthetic results. 相似文献
89.
The first polar body does not predict accurately the location of the metaphase II meiotic spindle in mammalian oocytes 总被引:10,自引:0,他引:10
OBJECTIVE: To evaluate how well polar body location predicts spindle localization and to examine spindle morphology. DESIGN: Randomized, controlled animal study. SETTING: University-affiliated research laboratory. ANIMAL(S): Mature, female golden hamsters. INTERVENTION(S): After superovulation with pregnant mare serum gonadotropin and hCG, metaphase II oocytes were obtained and imaged under digital polarization microscopy. MAIN OUTCOME MEASURE(S): Identify the meiotic spindle in living, unfixed hamster oocytes and determine spindle location relative to the polar body. RESULT(S): Spindles were imaged in 30 oocytes and only in 5 of them could the polar body predict the spindle localization. In the remaining oocytes, the spindles presented a random distribution within the cytoplasm. CONCLUSION(S): These data show that the polar body location is not an accurate predictor for meiotic spindle location in mammalian oocytes. 相似文献
90.
Age-related postural deficits elicit compensatory mechanisms such as ankle dorsiflexion in the elderly. To gain further insight into this problem, the ability to match an ankle angle during quiet stance was studied in 12 elderly and 12 young subjects. Following an initial single limb angular perturbation presented in the ±4° range, a subject had to return a tilt platform to level, as determined by the nonperturbed limb. Elderly subjects exhibited significant positive (0.9°) over-shoot of the level position, in contrast to young subjects who matched ankle angle with a mean error of −0.1°. The elderly group also exhibited an increase in positioning error for angular displacements in the range between −1 and +1°. The results document age-related postural changes in ankle positioning which might affect postural stability in older adults. 相似文献