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1.
Arteriovenous malformations (AVM) of the uterus can cause life‐threatening hemorrhage. Unexplained, heavy vaginal bleeding in a reproductive age woman should raise suspicion for an AVM. Here a 37‐year‐old woman had increasingly severe vaginal bleeding for 15 days. Serum β‐hCG was elevated. Two‐dimensional transvaginal ultrasound suggested retained products of conception. Before dilation and curettage (D&C), color Doppler and three‐dimensional (3D) power Doppler demonstrated findings indicative of uterine AVM. A bilateral uterine artery embolization was performed without complications. Three months after uterine artery embolization, 3D power Doppler ultrasonography found complete resolution of the AVM. This case illustrates the importance of assessing both gray‐scale and 3D power Doppler, and the ability of postprocedure Doppler to assess resolution. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound 43:327–334, 2015  相似文献   
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Objectives

To understand the pathology of the ultrastructure of enamel affected by systemic disorders which disrupt enamel tissue formation in order to give insight into the precise mechanisms of matrix-mediated biomineralization in dental enamel in health and disease.

Methods

Two-dimensional synchrotron X-ray diffraction has been utilized as a sophisticated and useful technique to spatially quantify preferred orientation in mineralized healthy deciduous dental enamel, and the disrupted crystallite organization in enamel affected by a systemic disease affecting bone and dental mineralization (mucopolysaccharidosis Type IVA and Type II are used as examples). The lattice spacing of the hydroxyapatite phase, the crystallite size and aspect ratio, and the quantified preferred orientation of crystallites across whole intact tooth sections, have been determined using synchrotron microdiffraction.

Results

Significant differences in mineral crystallite orientation distribution of affected enamel have been observed compared to healthy mineralized tissue. The gradation of enamel crystal orientation seen in healthy tissue is absent in the affected enamel, indicating a continual disruption in the crystallite alignment during mineral formation.

Conclusions

This state of the art technique has the potential to provide a unique insight into the mechanisms leading to deranged enamel formation in a wide range of disease states.

Clinical relevance

Characterising crystal orientation patterns and geometry in health and following disruption can be a powerful tool in advancing our overall understanding of mechanisms leading to the tissue phenotypes seen clinically. Findings can be used to inform the appropriate dental management of these tissues and/or to investigate the influence of therapeutic interventions or external stressors which may impact on amelogenesis.  相似文献   
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Our objective was to define optimal management of distal ureteric strictures following renal transplantation. A systematic review on PubMed identified 34 articles (385 patients). Primary endpoints were success rates and complications of specific primary and secondary treatments (following failure of primary treatment). Among primary treatments (n = 303), the open approach had 85.4% success (95% CI 72.5–93.1) and the endourological approach had 64.3% success (95% CI 58.3–69.9). Among secondary treatments (n = 82), the open approach had 93.1% success (95% CI 77.0–99.2) and the endourological approach had 75.5% success (95% CI 62.3–85.2). The most common primary open treatment was ureteric reimplantation (n = 33, 81.8% success, 95% CI 65.2–91.8). The most common primary endourological treatment was dilation (n = 133, 58.6% success, 95% CI 50.1–66.7). Fourteen complications, including death (4 weeks post‐op) and graft loss (12 days post‐op), followed endourological treatment. One complication followed open treatment. This is the first systematic review to examine the success rates and complications of specific treatments for distal ureteric strictures following renal transplantation. Our review indicates that open management has higher success rates and fewer complications than endourological management as a primary and secondary treatment for post‐transplant distal ureteric strictures. We also outline a post‐transplant ureteric stricture evaluation and treatment algorithm.  相似文献   
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Aims

Medicine-related problems (MRPs) represent a major issue leading to hospitalization, especially in adult and elderly patients. The aims of this review are to investigate the prevalence, causes and major risk factors for MRPs leading to hospitalization in adult patients and to identify the main medicine classes involved.

Methods

Studies were identified through electronic searches of Medline, Embase, Scopus and International Pharmaceutical Abstracts between January 2000 and May 2013. A systematic review was conducted of both retrospective and prospective studies. Studies included were those involving hospitalization resulting from MRPs in adults (≥18 years old), whereas studies excluded were those investigating drug misuse and abuse and studies investigating MRPs in hospitalized patients. Data analysis was performed using SPSS version 20.

Results

Forty-five studies were identified, including 21 that investigated hospitalization resulting from adverse drug reactions, six studies that investigated hospitalization due to adverse drug events and 18 studies that investigated hospitalization due to MRPs. The median prevalence rates of hospitalization resulting from adverse drug reactions, adverse drug events and MRPs were 7% (interquartile range, 2.4–14.9%), 4.6% (interquartile range, 2.85–16.6%) and 12.1% (interquartile range, 6.43–22.2%), respectively. The major causes contributing to MRPs were adverse drug reactions and noncompliance. In addition, the major risk factors associated with MRPs were old age, polypharmacy and comorbidities. Moreover, the main classes of medicines implicated were medicines used to treat cardiovascular diseases and diabetes.

Conclusions

Hospitalization due to MRPs had a high prevalence, in the range of 4.6–12.1%. Most MRPs encountered were prevalent among adult patients taking medicines for cardiovascular diseases and diabetes.  相似文献   
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Background

Patent ductus arteriosus is generally associated with hyperdynamic status. Given the vascular shunt between the aorta and pulmonary artery, intrinsic aortic changes occur (aortic stiffness). In the present study, we attempted to assess the impact of PDA on aortic stiffness and its connection with cardiovascular function before and after transcatheter closure of PDA.

Patient and methods

Our study consisted of 60 children who were preparing for transcatheter closure of PDA and 60 healthy controls. All patients had clinical and echocardiographic proof of hemodynamically significant PDA.

Results

Patients with PDA exhibited significantly higher ASI than controls before closure (p-value?<?0.05). After closure, ASI was significantly reduced (p-value?<?0.05), but still higher than that of controls (p-value?<?0.05) at the six-month follow-up assessment. Patients with PDA had significantly lower LVEF than controls before closure (p-value?<?0.05). After closure, LVEF was significantly enhanced (p-value?<?0.05), and no significant difference was noted amongst patients and controls (p-value?<?0.05) at the six-month follow-up assessment.

Conclusion

Aortic stiffness is significantly increased in patients with PDA regardless of PDA size. Aortic stiffness is related to reduced heart function. ASI may be valuable for observing the course of patients with PDA before and after intervention.  相似文献   
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The transplantation of the human T-cell acute lymphoblastic leukaemia (T-ALL) cell line HSB-2 into severe combined immunodeficient (SCID) mice was found to produce a disseminated pattern of leukaemia similar to that seen in man. The intravenous injection of 10(7) HSB-2 cells was associated with a universally fatal leukaemia. Histopathological examination of animals revealed the spread of leukaemia initially from bone marrow to involve all major organs including the meninges. An immunotoxin (HB2-Sap) was constructed by conjugating the anti-CD7 MAb HB2 to the ribosome-inactivating protein saporin. An in vitro protein synthesis inhibition assay revealed specific delivery of HB2-Sap immunotoxin (IT) to CD7+ HSB-2 target cells with an IC50 of 4.5 pM. When SCID mice were injected with 10(6) HSB-2 cells and then treated 8 days later with a single intravenous dose of 10 micrograms of immunotoxin there was a significant therapeutic effect evidenced by the numbers of animals surviving in the therapy group compared with untreated controls (chi 2 = 5.348, P = 0.021). These results demonstrate the useful application of human leukaemia xenografts in SCID mice and the potential therapeutic effect of an anti-CD7 immunotoxin in human T-ALL.  相似文献   
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Ultrasound has an ever-increasing role in the delivery of therapeutic agents, including genetic material, protein and chemotherapeutic agents. Cavitating gas bodies, such as microbubbles, are the mediators through which the energy of relatively non-interactive pressure waves is concentrated to produce forces that permeabilise cell membranes and disrupt the vesicles that carry drugs. Thus, the presence of microbubbles enormously enhances ultrasonic delivery of genetic material, proteins and smaller chemical agents. Numerous reports show that the most efficient delivery of genetic material occurs in the presence of cavitating microbubbles. Attaching the DNA directly to the microbubbles, or to gas-containing liposomes, enhances gene uptake even further. Ultrasonic-enhanced gene delivery has been studied in various tissues, including cardiac, vascular, skeletal muscle, tumour and even fetal tissue. Ultrasonic-assisted delivery of proteins has found most application in transdermal transport of insulin. Cavitation events reversibly disrupt the structure of the stratus corneum to allow transport of these large molecules. Other hormones and small proteins could also be delivered transdermally. Small chemotherapeutic molecules are delivered in research settings from micelles and liposomes exposed to ultrasound. Cavitation appears to play two roles: it disrupts the structure of the carrier vesicle and releases the drug; and makes cell membranes and capillaries more permeable to drugs. There remains a need to better understand the physics of cavitation of microbubbles and the impact that such cavitation has on cells and drug-carrying vesicles.  相似文献   
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