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991.
Ectopic ureter and ureterocele: their varied sonographic manifestations   总被引:1,自引:0,他引:1  
The sonographic examinations of four patients with simple ectopic ureters and 11 with ectopic ureteroceles were reviewed to determine distinguishing characteristics. Ectopic ureters, in cases of extreme dilatation and tortuosity, sometimes mimic multiseptated, cystic abdominal masses. However, the proximal portions of some severely dilated ureters are surprisingly small. Ectopic ureters sometimes indent the lower vesical wall, simulating a ureterocele. Ectopic ureteroceles are dynamic structures, changing in shape and size according to intravesical pressure. The lower pole of a duplex kidney may be difficult to detect because of displacement by the dilated upper renal pelvis and ureter. The renal parenchyma associated with an ectopic ureter may be equally difficult or impossible to find because of diminutive dysplasia or, less commonly, acquired atrophy. Dysplasia is characterized sonographically by highly echogenic parenchyma, lack of corticomedullary differentiation, and occasionally massive enlargement by cysts. Ectopic ureters and ureteroceles can be identified by fetal sonography.  相似文献   
992.
The distribution of IgG-subclasses provides insight in the immunological mechanisms of protection against whooping cough. We investigated the effect of Dutch whole-cell pertussis and acellular pertussis vaccines administered in infancy on the IgG-subclass distributions in healthy children aged 12 months, 4 years and 9 years as well as in children who have been infected with Bordetella pertussis.A fluorescent bead-based multiplex immunoassay was used for the measurement of IgG1, IgG2, IgG3 and IgG4 responses against pertussis toxin, filamentous heamagglutinin and pertactin.Although IgG1 was the predominant subclass for all pertussis antigens in both healthy and infected children, elevated IgG4 levels were only present in children who had received repeated number of acellular pertussis vaccinations. IgG2 and IgG3 antibodies did not contribute to the IgG response. No differences in IgG-subclasses between healthy vaccinated or infected children were found.The pertussis vaccine used for priming seems to determine the IgG-subclass composition elicited after a secondary antibody response either induced by pertussis vaccination or infection. The pronounced anti-pertussis IgG4 response might reflect the Th2-skewing of the immune response after aP vaccination.  相似文献   
993.
Background  HIV testing is cost-effective in unselected general medical populations, yet testing rates among those at risk remain low, even among those with regular primary care. HIV rapid testing is effective in many healthcare settings, but scant research has been done within primary care settings or within the US Department of Veteran’s Affairs Healthcare System. Objectives  We evaluated three methods proven effective in other diseases/settings: nurse standing orders for testing, streamlined counseling, and HIV rapid testing. Design  Randomized, controlled trial with three intervention models: model A (traditional counseling/testing); model B (nurse-initiated screening, traditional counseling/testing); model C (nurse-initiated screening, streamlined counseling/rapid testing). Participants  Two hundred fifty-one patients with primary/urgent care appointments in two VA clinics in the same city (one large urban hospital, one freestanding outpatient clinic in a high HIV prevalence area). Measurements  Rates of HIV testing and receipt of results; sexual risk reduction; HIV knowledge improvement. Results  Testing rates were 40.2% (model A), 84.5% (model B), and 89.3% (model C; p = <.01). Test result receipt rates were 14.6% (model A), 31.0% (model B), 79.8% (model C; all p = <.01). Sexual risk reduction and knowledge improvement did not differ significantly between counseling methods. Conclusions  Streamlined counseling with rapid testing significantly increased testing and receipt rates over current practice without changes in risk behavior or posttest knowledge. Increased testing and receipt of results could lead to earlier disease identification, increased treatment, and reduced morbidity/mortality. Policymakers should consider streamlined counseling/rapid testing when implementing routine HIV testing into primary/urgent care.  相似文献   
994.
Current dietary recommendations advise reducing the intake of saturated fatty acids (SFAs) to reduce coronary heart disease (CHD) risk, but recent findings question the role of SFAs. This expert panel reviewed the evidence and reached the following conclusions: the evidence from epidemiologic, clinical, and mechanistic studies is consistent in finding that the risk of CHD is reduced when SFAs are replaced with polyunsaturated fatty acids (PUFAs). In populations who consume a Western diet, the replacement of 1% of energy from SFAs with PUFAs lowers LDL cholesterol and is likely to produce a reduction in CHD incidence of ≥2-3%. No clear benefit of substituting carbohydrates for SFAs has been shown, although there might be a benefit if the carbohydrate is unrefined and has a low glycemic index. Insufficient evidence exists to judge the effect on CHD risk of replacing SFAs with MUFAs. No clear association between SFA intake relative to refined carbohydrates and the risk of insulin resistance and diabetes has been shown. The effect of diet on a single biomarker is insufficient evidence to assess CHD risk. The combination of multiple biomarkers and the use of clinical endpoints could help substantiate the effects on CHD. Furthermore, the effect of particular foods on CHD cannot be predicted solely by their content of total SFAs because individual SFAs may have different cardiovascular effects and major SFA food sources contain other constituents that could influence CHD risk. Research is needed to clarify the role of SFAs compared with specific forms of carbohydrates in CHD risk and to compare specific foods with appropriate alternatives.  相似文献   
995.
The neural retina is an extrapituitary site of growth hormone (GH) production and an autocrine or paracrine site of retinal GH action. Retinal GH is released from retinal tissue and may be secreted into the vitreous. Ontogenetic changes in the abundance of retinal GH during embryogenesis indicate that the amount of GH released may be regulated. The presence of pituitary GH secretagogues (GH-releasing hormone, GHRH; thyrotropin-releasing hormone, TRH; and ghrelin) and pituitary GH inhibitors (somatostatin, SRIF and insulin-like growth factor, IGF-1) within the neural retina may indicate the involvement of these factors in retinal GH release. This possibility is supported by the finding that GHRH is colocalized with GH in chick retinal ganglion cells (RGCs) and in immortalized cells (QNRD) derived from quail neuroretinal cells and by the induction of GH mRNA in incubated QNRD cells. In summary, these results provide evidence for the autocrine or paracrine regulation of retinal GH release in the ganglion cells of the embryonic chick retina.  相似文献   
996.
Objective. Giardia lamblia is the most common enteric protozoan world-wide. The prevalence varies internationally. Patients with giardiasis typically have diarrhoea but may have atypical symptoms when referred for endoscopy. The purpose of this study was to investigate whether a policy of routine duodenal biopsies increased the yield of diagnosing Giardia and whether treatment improved the patient's presenting symptoms. Material and methods. Our hospital endoscopy database was examined retrospectively, from January 2003 to January 2004, to identify patients who had undergone gastroscopy and targeted duodenal biopsies. Thereafter, routine duodenal biopsies were carried out prospectively on unselected adult patients referred for gastroscopy from January 2004 to April 2006. Patients diagnosed with Giardia were assessed for symptoms and response to treatment. Results. In the retrospective group, of the 5979 gastroscopies performed, 1464 duodenal biopsies were carried out; 5 patients had giardiasis, a prevalence of 0.08%, CI 0.01–0.16%. In the prospective group, 2000 gastroscopies with duodenal biopsies were performed; 9 patients had giardiasis, a prevalence of 0.45%, CI 0.16–0.74%. The difference in prevalence was 0.37%, CI 0.06–0.67%, which was statistically significant with a Yates’ χ2CC of 9.49, p<0.005. On comparing response to treatment, the Fisher exact test revealed a proportional difference that was not statistically significant. Conclusions. In a UK population, the prevalence of Giardia was low. Although a policy of routine duodenal biopsy resulted in more cases of Giardia being identified, this increase in detection did not correspond with an improvement in patients’ symptoms. This suggests that Giardia may be a coincidental finding. This study does not support the approach of routine duodenal biopsy in diagnosing giardiasis.  相似文献   
997.
BACKGROUND: Little is known about the infrastructure to train gastroenterologists in capsule endoscopy. The level of capsule endoscopy exposure among trainees in the United Kingdom or Europe has also not been quantified. AIMS AND METHODS: To assess the ability of 10 gastroenterology trainees with endoscopy experience to interpret 10 capsule endoscopy videos against five medical students, with an expert in capsule endoscopy as the gold standard. Parameters assessed included gastric emptying time, small bowel transit and the diagnosis made. A questionnaire survey assessed the level of capsule endoscopy exposure among United Kingdom trainees. RESULTS: Trainees were better at determining the gastric emptying time (p=0.013) and more likely to record true positives compared to the students (p=0.037). They were also less likely to record false positives (p=0.005) and more likely to reach the correct diagnosis (p=0.001, OR 3.6, CI 1.8-7.4). Our survey found that, 65% of trainees had prior exposure to capsule endoscopy but only 13% had done capsule endoscopy reporting. Sixty seven percent felt capsule endoscopy should be incorporated into their training. CONCLUSION: This study has shown that prior endoscopic experience enables trainees to interpret capsule endoscopy more accurately than medical students. However, there is a demand for focussed training which would enable trainees to reliably interpret pathology on capsule endoscopy.  相似文献   
998.
Eight patients with Fanconi's anemia were given cyclophosphamide alone (seven patients) or combined with procarbazine and antithymocyte globulin (one patient) followed by marrow grafts from HLA-identical siblings. All patients had engraftment. Seven developed acute and three chronic graft-versus-host disease (GVHD). Three patients died with GVHD and infectious complications (days 19, 56, and 82) and one with an intracerebral hemorrhage (day 540). Four patients are surviving 647- 3435 days after grafting, two are well, and two have chronic GVHD that is improving. These results show that Fanconi's anemia can be treated successfully by allogeneic marrow transplantation.  相似文献   
999.
The treatment of keloid and hypertrophic scars remains difficult. Enzymatic digestion of keloid scars has been previously proposed as an effective treatment strategy for reducing the volume of keloid scars. To test this, we administered intra-lesional injections of pure collagenase (between 600 and 4500 units for each scar) into the keloid and hypertrophic scars of seven human volunteers (five keloid and two hypertrophic scars). Five patients (three keloid and two hypertrophic) received more than one injection of collagenase. The treatment resulted in a temporary reduction in scar volume for three of the patients with keloid scars. However, scar volumes for these three patients returned to the same (or greater) levels after 6 months of follow-up. Treatment with collagenase produced no change in scar volume for the two patients with hypertrophic scar. Side effects were numerous and severe including; pain, swelling, blistering, ulceration and ecchymosis at the site of injection. One patient required admission to hospital for 48 h after the first injection. Maximum length of follow-up was 6 months. None of the seven patients completed the study and returned for final follow-up at 2 years. This pilot study suggests that treatment of keloid and hypertrophic scars with intra-lesional injections of collagenase is ineffective.  相似文献   
1000.
The use of nanoparticles (NPs) for intranasal (IN) drug delivery to the brain represents a hopeful strategy to enhance brain targeting of anti-epileptic drugs. In the present work, chitosan–lecithin NPs loaded with phenytoin (PHT), were prepared using the nano-precipitation method. The spherical nature of the NPs and their stability were confirmed using scanning and transmission electron microscopy, while the average dynamic size and zeta potential were measured using dynamic light scattering. The encapsulation efficiency of PHT was higher than 60% for all prepared NPs. Release studies showed that the amount of released PHT was directly related to the amount of chitosan used. The optimum preparation, L10Ci+ was administered via the IN route, and the levels of PHT in the brain were measured in three-time points. Two experimental controls were given via the intraperitoneal (IP) and IN routes. The highest PHT amount reaching 1.01 ± 0.55% for L10Ci+, which was associated with a sustained release of PHT. These preliminary findings show that the IN delivery of PHT-loaded NPs is very promising for managing epilepsy. The direct nose-to-brain approach increases the safety margins of PHT, while the sustained release could improve patient compliance in a clinical setting.

The use of nanoparticles (NPs) for intranasal (IN) drug delivery to the brain represents a hopeful strategy to enhance brain targeting of anti-epileptic drugs.  相似文献   
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