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Purpose

Percutaneous biopsy obtained from a single location is prone to sampling error in large heterogeneous renal masses, leading to nondiagnostic results or failure to detect poor prognostic features. We evaluated the accuracy of percutaneous biopsy for large renal masses using a modified multi-quadrant technique vs. a standard biopsy technique.

Materials and methods

Clinical and pathological data for all patients with cT2 or greater renal masses who underwent percutaneous biopsy from 2009 to 2014 were reviewed. The multi-quadrant technique was defined as multiple core biopsies from at least 4 separate solid enhancing areas in the tumor. The incidence of nondiagnostic findings, sarcomatoid features and procedural complications was recorded, and concordance between biopsy specimens and nephrectomy pathology was compared.

Results

A total of 122 biopsies were performed for 117 tumors in 116 patients (46 using the standard biopsy technique and 76 using the multi-quadrant technique). Median tumor size was 10 cm (IQR: 8–12). Biopsy was nondiagnostic in 5 of 46 (10.9%) standard and 0 of 76 (0%) multi-quadrant biopsies (P = 0.007). Renal cell carcinoma was identified in 96 of 115 (82.0%) tumors and nonrenal cell carcinoma tumors were identified in 21 (18.0%). One complication occurred using the standard biopsy technique and no complications were reported using the multi-quadrant technique. Sarcomatoid features were present in 23 of 96 (23.9%) large renal cell carcinomas studied. Sensitivity for identifying sarcomatoid features was higher using the multi-quadrant technique compared to the standard biopsy technique at 13 of 15 (86.7%) vs. 2 of 8 (25.0%) (P = 0.0062).

Conclusions

The multi-quadrant percutaneous biopsy technique increases the ability to identify aggressive pathological features in large renal tumors and decreases nondiagnostic biopsy rates.  相似文献   
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Solar ultraviolet light electromagnetic waves are a known environmental carcinogenic agent closely associated with the development of skin cancer in light‐complexioned individuals. Outdoor workers have higher annual exposure to ultraviolet light. We will review the topic of actinic keratoses among these individuals as this common rudimentary form of superficial cutaneous squamous cell carcinoma is explored in greater detail.  相似文献   
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This study analyses the priorities of public donors in funding HIV prevention by either integrated condom programming or HIV preventive microbicides and vaccines in the period between 2000 and 2008. It further compares the public funding investments of the USA government and European governments, including the EU, as we expect the two groups to invest differently in HIV prevention options, because their policies on sexual and reproductive health and rights are different. We use two existing officially UN endorsed databases to compare the public donor funding streams for HIV prevention of these two distinct contributors. In the period 2000-2008, the relative share of public funding for integrated condom programming dropped significantly, while that for research on vaccines and microbicides increased. The European public donors gave a larger share to condom programming than the United States, but exhibited a similar downward trend in favour of funding research on vaccines and microbicides. Both public donor parties invested progressively more in research on vaccines and microbicides rather than addressing the shortage of condoms and improving access to integrated condom programming in developing countries.  相似文献   
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Parasitology Research - Malaria is transmitted through the injection of Plasmodium sporozoites into the skin by Anopheles mosquitoes. The parasites first replicate within the liver before infecting...  相似文献   
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For medical students first entering the clinical space in July 2020, the unique challenges related to the coronavirus pandemic threatened to amplify the psychological distress associated with clerkship rotations. This study aimed to characterize the mental health of third-year medical students starting clinical clerkships in the midst of a pandemic by assessing symptoms of major depressive disorder (MDD), generalized anxiety disorder (GAD), and posttraumatic stress disorder (PTSD) as well as risk, coping, and protective factors associated with psychological outcomes. Of 147 third-year medical students at the Icahn School of Medicine at Mount Sinai in New York City, 110 (75%) participated in this prospective survey-based study with 108 included in the final analysis. 43 (39.8%) respondents screened positive for symptoms of either MDD, GAD, or PTSD. Multiple regression analyses revealed that greater overall symptom severity was associated with more avoidant coping, more traumatic events witnessed, poorer student and leisure functioning, lower trait emotional stability, and lower social support. Worries related to COVID-19 did not significantly influence outcome variables. To better understand the role of the pandemic on psychological outcomes in third-year medical students, additional research should focus on the trajectory of these outcomes over the year during the coronavirus pandemic.

  相似文献   
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AIM: To study blood flow along the internal jugular veins (IJV) in the initial state and under the action of nitroglycerin in patients with essential arterial hypertension (EAH) with reference to characteristics of a 24-h profile of blood pressure. MATERIAL AND METHODS: A 24-h monitoring of blood pressure (MBP), duplex scanning of IJV, venous IJV outflow were studied in 26 patients with EAH stage 2 (mean age 39 +/- 5.0) before and after sublingual intake of nitroglycerin (0.5 mg). RESULTS: By 24-h MBP findings, two groups of patients were identified: with unaffected blood pressure profile (group 1) and affected profile (group 2). Nitroglycerin produced a unidirectional reaction of IJV (increased outflow) in group 1 and multidirectional changes of venous outflow along the IJV in patients of group 2. CONCLUSION: Nitroglycerin test showed different venous cerebral hemodynamics in EAH patients with different variants of 24-h MBP.  相似文献   
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