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91.
PURPOSE: To describe the sonographic and mammographic appearance of granular cell tumors (GCTs) of the breast in 6 patients with pathological correlation. METHODS: A search was conducted of the cyto-histopathological database in a single institution from 1990 to 2004 for breast lesions given the diagnosis of GCT of the breast. Six patients with GCT of the breast who underwent mammographic or sonographic examination or both before surgery were included in this study. RESULTS: The mammographic features of GCT of the breast were indeterminate in most patients, often presenting as an isodense mass with indistinct or spiculated margins. Calcifications were not a feature. The sonographic features of GCT of the breast mimicked carcinoma, including heterogeneous echotexture, indistinct margins, and hypervascularity. Hyperechogenicity was noted in 5 of 7 (71%) GCTs in this series. The cytomorphological features of GCT included sheets of large granular cells intersected by arborizing thin-walled blood vessels. The cells had round to oval nuclei, inconspicuous nucleoli, and abundant, ill-defined granular cytoplasm. CONCLUSIONS: Breast imagers should be aware that GCT of the breast is an uncommon differential in a minority of neoplasms that can be mistaken for breast cancer.  相似文献   
92.
The aim of this study was to determine the prevalence of drug-resistant tuberculosis (TB) and its associated risk factors. The susceptibilities of Mycobacterium tuberculosis isolates were tested against four first-line antituberculous drugs and were typed by spoligotyping. Spoligotyping of M. tuberculosis strains resulted in 95 different patterns that were divided into three evolutionary groups (1-3). Eighty-six (90%) of the isolates had unique patterns that were reported for the first time. Interestingly, 9.4% of the strains belonged to the Beijing family. Multidrug resistance (MDR) was seen in group 1 of the evolutionary scenario. All M. tuberculosis isolates belonging to the Beijing family were associated with a resistance pattern. MDR was much higher in bacteria isolated from Afghan TB patients residing in Iran.  相似文献   
93.
This research sought to determine the shear bond strength, degree of resin infiltration and failure mode when organic solvent-based adhesives (acetone or ethanol) were used in immediate bonding to enamel bleached with 10% carbamide peroxide or 38% hydrogen peroxide systems. Seventy-two non-carious bovine incisors were randomly assigned to three groups of 24 specimens each-control group (deionized water), 38% hydrogen peroxide bleach group and 10% carbamide peroxide bleach group. Each group was further subdivided into two subgroups of 12 specimens each according to the adhesive system used to bond the resin composite to enamel surfaces. The two adhesive systems used were Single Bond, an ethanol-based adhesive, and One Step, an acetone-based adhesive. The shear bond strengths of 38% hydrogen peroxide and 10% carbamide peroxide were significantly lower compared to the non-bleached controls. Fractography revealed an adhesive failure mode in all specimens. Qualitative comparisons of resin tags present in the bleached and unbleached specimens using scanning electron microscopy (SEM) revealed few, thin and fragmented resin tags when 38% hydrogen peroxide and 10% carbamide peroxide were used.  相似文献   
94.

Background

The dietary habits of Americans are creating serious health concerns, including obesity, hypertension, diabetes, cardiovascular disease, and even some types of cancer. While considerable attention has been focused on calorie reduction and weight loss, approaches are needed that will not only help the population reduce calorie intake but also consume the type of healthy, well-balanced diet that would prevent this array of medical complications.

Objective

To design an Internet-based nutrition education program and to explore its effect on weight, blood pressure, and eating habits after 12 months of participation.

Methods

We designed the DASH for Health program to provide weekly articles about healthy nutrition via the Internet. Dietary advice was based on the DASH diet (Dietary Approaches to Stop Hypertension). The program was offered as a free benefit to the employees of EMC Corporation, and 2834 employees and spouses enrolled. Enrollees voluntarily entered information about themselves on the website (food intake), and we used these self-entered data to determine if the program had any effect. Analyses were based upon the change in weight, blood pressure, and food intake between the baseline period (before the DASH program began) and the 12th month. To be included in an outcome, a subject had to have provided both a baseline and 12th-month entry.

Results

After 12 months, 735 of 2834 original enrollees (26%) were still actively using the program. For subjects who were overweight/obese (body mass index > 25; n = 151), weight change at 12 months was -4.2 lbs (95% CI: -2.2, -6.2; P < .001). For subjects with hypertension or prehypertension at baseline (n = 62), systolic blood pressure fell 6.8 mmHg at 12 months (CI: -2.6, -11.0; P < .001; n = 62). Diastolic pressure fell 2.1 mmHg (P = .16). Based upon self-entered food surveys, enrollees (n = 181) at 12 months were eating significantly more fruits, more vegetables, and fewer grain products. They also reduced consumption of carbonated beverages. Enrollees who had visited the website more often tended to have greater blood pressure and weight loss effect, suggesting that use of the DASH for Health program was at least partially responsible for the benefits we observed.

Conclusions

We have found that continued use of a nutrition education program delivered totally via the Internet, with no person-to-person contact with health professionals, is associated with significant weight loss, blood pressure lowering, and dietary improvements after 12 months. Effective programs like DASH for Health, delivered via the Internet, can provide benefit to large numbers of subjects at low cost and may help address the nutritional public health crisis.  相似文献   
95.
Invasive ductal and lobular breast carcinomas often have different preferred metastasis sites and distinct histomorphologic characteristics. Their metastatic cytomorphologic cell features in body cavity fluids are generally readily recognized, but the single-cell/mesothelial-like pattern and its relationship to the primary tumor type have not been well studied, nor whether metastases have a propensity for certain body cavity sites on the basis of the primary tumor type. To further assess the tumor type and single-cell pattern of breast carcinoma metastases in pleural and peritoneal effusions, we retrospectively studied 853 pleural and peritoneal effusions and correlated the findings with the primary tumor type. When necessary, the single- cell/mesothelial-like pattern was documented immunohistochemically. Metastatic breast carcinomas represented 249 (50.8%) of 490 pleural and 51 (14.0%) of 363 peritoneal effusions. Most metastases in pleural and peritoneal effusions were ductal carcinomas (92.4% and 62.7%, respectively). Lobular carcinoma accounted for only 2 (0.8%) of 249 pleural and 11 (21.6%) of 51 peritoneal effusions. The single-cell/mesothelial-like cell pattern was found in all lobular carcinomas but also in 11 (6.0%) of 184 reviewed ductal carcinomas (nine pleural and two peritoneal). Awareness of these findings and the use of immunohistochemical analyses are necessary for accurately diagnosing metastatic breast carcinoma, especially lobular type.  相似文献   
96.
Cryptosporidium is a significant cause of diarrheal disease in developing and industrialized nations. Cryptosporidium hominis and Cryptosporidium parvum are the main agents of cryptosporidiosis in humans. In Egypt, very little is known about genetic structure of Cryptosporidium spp. Therefore, this study was designed to examine samples from sporadic cases of cryptosporidiosis in Egyptians in order to identify the species involved in infection as well as the transmission dynamics and distribution of the parasite in the Great Cairo area. A total of 391 human faecal samples were collected, between May 2008 and March 2009, from ten public hospitals in Great Cairo. Initial screening by immunochromatographic detection kit “the Stick Crypto-Giardia; Operon” showed 23 possible positive cases. Twenty of them were confirmed by microscopic examination. PCR was performed by amplification of the oocyst wall protein (COWP) gene where 18 out of 23 samples were positive, one not detected by microscopy. Cryptosporidium genotyping was performed by RFLP analysis of PCR products of the diagnosis PCR. Only 15 samples rendered a digestion pattern. The genotyping distribution was nine cases showing C. hominis genotype, three showing C. parvum genotype and three showing mixed infection by C. hominis and C. parvum. The data showed an elevated prevalence of C. hominis (80.0%), the most anthroponotic species, suggesting a human–human transmission. Furthermore, the presence of up to 40% of samples infected with C. parvum shows that further investigations are required to determine the subgenotypes of C. parvum to clarify the mode of transmission in order to improve the control measures.  相似文献   
97.
Nour S  LaRosa J  Inn KG 《Health physics》2011,101(2):170-175
The present challenge for the international emergency radiobioassay community is to analyze contaminated samples rapidly while maintaining high quality results. The National Institute of Standards and Technology (NIST) runs a radiobioassay measurement traceability testing program to evaluate the radioanalytical capabilities of participating laboratories. The NIST Radiochemistry Intercomparison Program (NRIP) started more than 10 years ago, and emergency performance testing was added to the program seven years ago. Radiobioassay turnaround times under the NRIP program for routine production and under emergency response scenarios are 60 d and 8 h, respectively. Because measurement accuracy and sample turnaround time are very critical in a radiological emergency, response laboratories' analytical systems are best evaluated and improved through traceable Performance Testing (PT) programs. The NRIP provides participant laboratories with metrology tools to evaluate their performance and to improve it. The program motivates the laboratories to optimize their methodologies and minimize the turnaround time of their results. Likewise, NIST has to make adjustments and periodical changes in the bioassay test samples in order to challenge the participating laboratories continually. With practice, radioanalytical measurements turnaround time can be reduced to 3-4 h.  相似文献   
98.
Many functional polymorphisms in the rennin-angiotensin system (RAS) have been described; these polymorphisms have been postulated to contribute to fibrosis in several diseases. Our aim was to study the frequency of ACE I/D polymorphism in chronic hepatitis C virus (HCV) infection and its association with liver fibrosis and response to treatment. This study included 90 patients with chronic hepatitis C. All patients received antiviral therapy in the form of pegylated interferon and ribavirin. Patients were grouped according to the stage of liver fibrosis by biopsy into: group 1 (fibrosis: 0 or 1); group 2 (fibrosis: 2 or 3) and group 3 (fibrosis: 4 or 5). The study included also 170 healthy subjects, as a control group. Polymerase chain reaction was carried out to detect the different ACE genotypes. The D/D genotype was significantly more prevalent among HCV patients compared to controls (65.6% vs 48.2%, P = 0.006). Degree of necroinflammation was significantly higher among patients with I/I genotype when compared to patients with D/D genotype (P = 0.04). No significant difference in the distribution of the ACE I/D genotypes between the fibrosis groups and between responders and non responders to interferon therapy. The D/D genotype may increase the susceptibility to infection with hepatitis C.  相似文献   
99.
100.
Clinical Rheumatology - To determine the influence of breastfeeding duration in the clinical activity of low-income juvenile idiopathic arthritis (JIA). Ninety-one JIA patients followed in...  相似文献   
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