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Helicobacter pylori exists in two distinct forms, rod shaped or coccoid, in stomachs of infected patients. Based on in vitro proteome comparisons, there are no detectable coccoid-specific proteins, which argues against the specific adaptation of coccoid Helicobacter to distinct biological functions, such as enhanced persistence or transmission to other hosts.  相似文献   
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Native arteriovenous fistula is the best available vascular access for hemodialysis in end-stage renal failure. It is characterized by higher patency rates and lower rates of morbidity, mortality and complication compared to prosthetic bypass grafts and central venous catheters. Aneurysmal complications remain the main complications of these access with a high risk of rupture and fatal hemorrhage. Their management varies from case to another and several methods are reported in the literature. We describe a case of an atypical localization of a juxta-anastomotic venous aneurysm in the anatomical snuffbox, treated by resection with proximal reimplantation of the cephalic vein at the wrist.  相似文献   
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BACKGROUND: Why do some patients suffer acute myocardial infarction (MI) despite angiographically normal coronary arteries (NL + MI) whereas others enjoy an acute MI-free life despite extensive three-vessel disease (3VD-MI)? The present study contrasts these two groups to identify some differences in the risk profile. METHODS: In 10,000 patients admitted to the cardiology service, a first MI was confirmed in 2356 patients, of whom 1609 underwent coronary angiography. In 77 patients with MI, coronary angiography was found to be entirely normal (NL + MI, 77/1609, 4.1%). These were contrasted to 123 patients with severe three-vessel coronary disease but no MI (3VD-MI). RESULTS: Patients with NL + MI were 13 years younger (42 +/- 8.3 vs 55 +/- 10.5, P < 0.05), with 33 patients (43%) under the age 40 years, in contrast to only 9 patients (7.3%) in the 3VD group being this age. Patients with NC + MI were more often current smokers (80.5% vs 29% in the 3VD group; P < 0.01). Patients with 3VD-MI were, on the other hand, more often diabetic (54% vs 9% in the NL + MI group; P < 0.01) and had a higher cholesterol level (5.6 +/- 1.1 vs 4.9 +/- 1.0 Mmol/l, P < 0.01) as well as a higher incidence of chronic stable angina (52% vs 22%; P < 0.01) and heart failure (6% compared with 0% in the NL + MI group). Sixty-one out of 77 (79%) NL + MI patients had a single risk factor, and in 87%, this was smoking alone. Diabetes mellitus was rare and never occurred alone in this group. CONCLUSION: In patients who suffer MI despite normal coronary angiography, smoking is a major risk factor: In contrast, in patients with extensive coronary artery disease on angiography but no MI, diabetes rather than smoking is the dominant risk factor. The findings of this study support the view that the risk factors for stable and unstable coronary artery disease are different, as reflected by the contrast of the above groups at the extremes of the spectrum. Smoking appears to be a major risk factor for acute MI (even with normal coronary angiography), whereas diabetes is a major risk factor for more severe but more stable coronary artery disease.  相似文献   
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The synthesis of inorganic rod shape nanostructures is important in chromatography, dentistry, and medical applications such as bone implants, and drug and gene delivery systems. Herein, calcium carbonate (CaCO3) nanowires were synthesized using a plant extract and the ensuing nanoparticles were characterized by XRD, FESEM, and HR-TEM. Then, the leishmanicidal effects of biogenic calcium carbonate nanowires were investigated against Leishmania major including the toxicity of varying concentrations of nanoparticles, and the percentage of viable and apoptotic cells based on flow cytometry analysis. Based on the results, the IC50 of these polymorphs were calculated to be 800 μg mL−1. An ecofriendly, inexpensive, and novel biogenic method for the production of a new advanced inorganic nanostructure, CaCO3 nanowires, is described without using hazardous chemicals; calcium carbonate nanowires maybe used as a smart drug carrier.

The synthesis of inorganic rod shape nanostructures is important in chromatography, dentistry, and medical applications such as bone implants, and drug and gene delivery systems.  相似文献   
77.

BACKGROUND

Professional organizations have issued guidelines recommending breast cancer screening for women 50 years of age.

OBJECTIVE

This study examines the percent of U.S. primary care physicians who report breast cancer screening practices that are not consistent with guidelines, and the characteristics of physicians who reported offering extra test modalities.

DESIGN

We analyzed a subset of a 2008 cross-sectional Women’s Health Care survey sent to primary care physicians randomly selected from the national American Medical Association (AMA) Physician Masterfile. A subset of physicians received a survey that presented a vignette of a health maintenance visit for an asymptomatic 51-year-old woman who was not at high risk for breast cancer. Responses were weighted to represent physicians nationally.

PARTICIPANTS

1,654 U.S. family physicians, general internists, and obstetrician-gynecologists under age 65, who practiced in office or hospital based settings (62.8 % response rate). After exclusions, 553 study physicians remained for analysis.

MAIN MEASURE

Physician self-report of breast cancer screening practices that are not consistent with the recommendations of the U.S. Preventive Services Task Force (USPSTF), the American College of Obstetrics and Gynecology (ACOG), and the American Cancer Society (ACS), defined as almost always offering mammography.

KEY RESULTS

36.0 % (95 % CI: 31.8 %–40.5 %) of physicians reported offering breast cancer screening tests inconsistent with national guidelines, with most offering extra tests (magnetic resonance imaging [MRI] and/or ultrasound) (33.2 %, 95 % CI 29.1 %–37.6 %). In adjusted analysis, risk-averse physicians and those who believed in the clinical effectiveness of MRI were more likely to offer extra breast cancer screening tests.

CONCLUSIONS

Physicians often report offering breast cancer screening test modalities beyond those recommended for a 51-year-old woman. Strategies, such as academic detailing regarding appropriate use of technology and provision of clinical decision support for breast cancer screening, could decrease overuse of resources.  相似文献   
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This article presents the findings of a self‐report study of the consequences of being an informal caregiver in Malaysia. The aim of this exploratory study was to examine Malaysian efforts in assisting informal caregivers, based on an analysis of the issues and concerns raised by the caregivers themselves. Data were obtained from a cross‐sectional survey of informal caregivers in 2009. This sample comprised parents, spouses and/or adult siblings, and adult children, caring for their children, spouses or siblings and parents who were chronically ill and/or had a disability. Of 300 prospective participants, only 175 could be located (58%), but all those contacted agreed to participate. Respondents were randomly selected and interviewed using a structured questionnaire to identify the emotional, financial, social and physical issues consequent upon being a caregiver. Most respondents reported that their care‐giving responsibilities had impacted their emotional, financial, social and/or physical well‐being. Inadequate and/or uncertain income was by far the greatest concern followed in descending order by social, physical and emotional consequences. The one‐way analysis of variance showed significant differences among the three categories of caregivers with respect to physical and emotional consequences. The findings show that care‐giving has detrimental effects on the lives of informal caregivers, and that they are in significant need of social support to help them deal with care‐giving tasks and responsibilities. Based on the findings, an integrated social support programme is proposed, tailored to the needs of informal caregivers.  相似文献   
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