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81.
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Kinnison  ML; Powe  NR; Steinberg  EP 《Radiology》1989,170(2):381-389
The authors reviewed 100 randomized controlled trials (RCTs) conducted in humans to compare safety or efficacy of new low-osmolality contrast media (LOM) with that of high-osmolality contrast media (HOM). Findings of the 43 RCTs judged to be of the highest quality suggest that the efficacy of LOM in imaging is equal or superior to that of HOM for all routes of administration. Heat sensation occurred less often with LOM for all routes and pain occurred less often with LOM for intraarterial routes. No differences were seen in nephrotoxicity or in frequency of nausea, vomiting, urticaria, bronchospasm, laboratory test abnormalities, or neurologic events. Greater cardiovascular changes were seen with HOM, including increased or decreased heart rate, increased left ventricular end-diastolic pressure, decreased systolic pressure, and QT prolongation, depending on route of administration. To demonstrate whether a reduction in clinically significant adverse outcomes truly occurs with LOM, trials will need to enlist larger numbers of patients and employ appropriate outcome measures. Future trials should stratify patients according to their risk of adverse reactions to provide better information about benefits of LOM in low- versus high-risk patients.  相似文献   
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Gain of chromosome 1q (+1q) is one of the most common recurrent cytogenetic abnormalities in multiple myeloma (MM), occurring in approximately 40% of newly diagnosed cases. Although it is often considered a poor prognostic marker in MM, +1q has not been uniformly adopted as a high-risk cytogenetic abnormality in guidelines. Controversy exists regarding the importance of copy number, as well as whether +1q is itself a driver of poor outcomes or merely a common passenger genetic abnormality in biologically unstable disease. Although the identification of a clear pathogenic mechanism from +1q remains elusive, many genes at the 1q21 locus have been proposed to cause early progression and resistance to anti-myeloma therapy. The plethora of potential drivers suggests that +1q is not only a causative factor or poor outcomes in MM but may be targetable and/or predictive of response to novel therapies. This review will summarize our current understanding of the pathogenesis of +1q in plasma cell neoplasms, the impact of 1q copy number, identify potential genetic drivers of poor outcomes within this subset, and attempt to clarify its clinical significance and implications for the management of patients with multiple myeloma.Subject terms: Cancer genomics, Myeloma, Myeloma  相似文献   
85.
Objective: To evaluate the influence of the local prenatal surveillance of twin pregnancies in the obstetrical results.

Methods: A prospective cohort study of multiple pregnancies delivered over a period of 16 years in a tertiary centre was conducted. In this study 861 twin pregnancies were included. They were compared for obstetric complications, gestational age at delivery, mode of delivery and birthweight, according to the place of the surveillance.

Results: Of the 861 cases examined, the following obstetric complications were significantly different: metrorrhagia (p?=?0.039), infections (p?p?=?0.007), PROMPT (p?p?=?0.024). The mode of delivery was similar but occurred mostly ≤32 weeks (p?p?Conclusion: Our results demonstrate the crucial importance of prenatal surveillance be carried in a differentiated referral centers with specific/strict protocols or the urgent implementation of same protocols in all other places of surveillance, since this straight surveillance greatly reduces the occurrence of prenatal complications, mainly PROMPT, PTD.  相似文献   
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To characterize the heterogeneity of severe (type III) von Willebrand disease (vWD), plasma and platelet von Willebrand factor antigen (vWF:Ag) and ristocetin cofactor activity (Ricof) were measured in 28 obligatory heterozygotes (ie, parents or children of probands from 15 different kindreds with severe vWD). On the average, heterozygotes had low levels of vWF in both platelets and plasma. There was, however, considerable heterogeneity, with four distinct patterns. Eleven heterozygotes had concordant reduction of vWF:Ag and Ricof in both plasma and platelets; five had low levels of vWF:Ag and Ricof in plasma contrasting with normal levels in platelets; eight had a peculiar pattern, the reverse of the above (ie, low levels in platelets and normal levels in plasma); and in one, both vWF measurements were normal in plasma and platelets. These patterns were genetically determined: they were consistent in four couples of consanguineous heterozygotes and in two couples carrying the same gene deletion. Only the remaining three heterozygotes had no clearly identifiable pattern. Other findings of this study were that although most of the heterozygotes had normal bleeding times, the 7 of 28 who had prolonged bleeding times had concordantly low levels of vWF measurements in both plasma and platelets. In conclusion, this large series of obligatory heterozygotes provides evidence for phenotypic and genotypic heterogeneity of severe vWD.  相似文献   
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Imatinib mesylate is a specific inhibitor of protein tyrosine kinase activity secondary to bcr-abl, mostly indicated for the treatment of patients with Philadelphia chromosome positive chronic myeloid leukaemia (CML). Generally, the undesirable effects of imatinib administration observed in clinical trials were of mild-to-moderate degree, and no haemolysis has been associated with this drug. We report here a case of immune-mediated haemolytic anaemia associated to imatinib mesylate successfully treated with prednisone in a patient with CML. Laboratory investigation showed anaemia [haemoglobin (Hb) of 59 g/L], reticulocyte of 61 x 10(9)/L and a positive direct antiglobulin test. Anti-drug in vitro studies revealed a positive result with gel microcolumn assay by an adsorption mechanism. Seventy-four days after prednisone therapy, the patient's Hb level was of 110 g/L with negative direct antiglobulin test and drug in vitro studies. This case demonstrated that patients treated with imatinib mesylate can present immune-mediated haemolysis and adequate management of this event can be done maintaining the drug and associating corticosteroids.  相似文献   
90.
BACKGROUND: Coronary angioplasty and stent implantation is effective as primary intervention in acute myocardial infarction. Because of fewer puncture site complications and improved patient comfort, transradial access has been increasingly used as an alternative to transfemoral access for percutaneous coronary interventions. METHODS AND RESULTS: We studied 103 patients (94 men, 9 women: mean age 52.5 +/- 11.96 years) with a diagnosis of acute myocardial infarction (<12 hours after onset), who underwent primary percutaneous coronary intervention. Transradial access was used in all patients with a normal Allen's test and transfemoral access was used additionally only if intra-aortic balloon counterpulsation was required. Follow-up duration was 6 months. Transradial access was successfully achieved in all patients. Radial artery cannulation took <2 min in more than 85% patients. During percutaneous coronary intervention, cannulation to balloon inflation times and total procedure times were 11.3 +/- 5.2 min and 19.9 +/- 10.8 min, respectively. Stents were implanted in 99 (96.1%) patients andplain balloon angioplastywas performed in 3.9%. The primary success rate was 98.1%, with no major bleeding complications. Total length of hospitalization averaged 2.4 +/- 0.8 days. In-hospital major adverse clinical events rate was 5.9%. Six-month clinical follow-up was achieved for 84 (86.6%) patients. Six (7.1%) patients died during follow-up. Follow-up coronary angiography was performed in 22 (26.2%) patients. After 6 months, 7 patients required revascularizationof the target lesion. The rate of survival without myocardial infarction, bypass surgery or repeat coronary angioplasty was 88.5% at 6 months. CONCLUSIONS: Transradial access may represent a safe and feasible technique for performing primary percutaneous coronary intervention with good acute results and without major bleeding complications.  相似文献   
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