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1.
Brucellosis is a world prevalent endemic illness that is transmitted from domestic animals to humans. Brucella spp. exploits urease for survival in the harsh conditions of stomach during the gastrointestinal infection. In this study, we examined the immune response and the protection elicited by using recombinant Brucella urease (rUrease) vaccination in BALB/c mice. The urease gene was cloned in pET28a and the resulting recombinant protein was employed as subunit vaccine. Recombinant protein was administered subcutaneously and intraperitoneally. Dosage reduction was observed with subcutaneous (SC) vaccination when compared with intraperitoneal (IP) vaccination. rUrease induced mixed Th1–Th2 immune responses with high titers of specific IgG1 and IgG2a. In lymphocyte proliferation assay, splenocytes from IP and SC‐vaccinated mice displayed a strong recall proliferative response with high amounts of IL‐4, IL‐12 and IFN‐γ production. Vaccinated mice were challenged with virulent Brucella melitensis, B. abortus and B. suis. The SC vaccination route exhibited a higher degree of protection than IP vaccination (p value ≤ 0.05). Altogether, our results indicated that rUrease could be a useful antigen candidate for the development of subunit vaccines against brucellosis.  相似文献   
2.

Background

In the emergency department, rib fractures are a common finding in patients who sustain chest trauma. Rib fractures may be a sign of significant, underlying pathology, especially in the elderly patients where rib fractures are associated with significant morbidity and mortality. To date, no studies have evaluated the ability of ultrasound to detect rib fractures using cadaver models and subsequently use this model as a teaching tool.

Objectives

The purpose of this study was to determine if it is possible to generate rib fractures on cadaver models which could be accurately identified using ultrasound.

Methods

This was a cross-sectional study performed during one session at a cadaver lab. A single hemithorax from four adult cadavers were used as models. Single rib fractures on each of rib five through eight were created. Four subjects, blinded to the normal versus fractured ribs, were asked to identify the presence of a fracture on each rib.

Results

A total of 8 of 16 potential ribs had fractured induced by study staff. Mean accuracy was 55% for all subjects. The overall sensitivity and specificity for detecting rib fractures was 50% (CI: 31.89–68.11) and 59.38% (CI: 35.69–73.55) respectively. The overall PPV and NPV was 55.17% and 54.29% respectively.

Conclusions

In this pilot study, subjects were not able to detect induced rib fractures using ultrasound on cadaver models. The use of this model as a teaching tool in the detection of rib fractures requires further investigation.  相似文献   
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Background: Few studies have examined the use of ultrasound for sciatic nerve localization. The authors evaluated the usefulness of low-frequency ultrasound in identifying the sciatic nerve at three locations in the lower extremity and in guiding needle advancement to target before nerve stimulation.

Methods: In this prospective observational study, 15 volunteers underwent sciatic nerve examination using a curved ultrasound probe in the range of 2-5 MHz and a Philips-ATL 5000 unit (ATL Ultrasound, Bothell, WA) in the gluteal, infragluteal, and proximal thigh regions. Thereafter, an insulated block needle was advanced inline with the ultrasound beam to reach the nerve target, which was further confirmed by electrical stimulation. The quality of sciatic nerve images, ease of needle to nerve contact, threshold stimulating current, and resultant motor response were recorded.

Results: The sciatic nerve was successfully identified in the transverse view as a solitary predominantly hyperechoic structure on ultrasound in all of the three regions examined. The target nerve was visualized easily in 87% and localized within two needle attempts in all patients. Nerve stimulation was successful in 100% after two attempts with a threshold current of 0.42 +/- 0.12 (mean +/- SD) eliciting foot plantarflexion or dorsiflexion.  相似文献   

8.
Background Gastrointestinal stromal tumours (GISTs) are thought to arise from the interstitial cells of Cajal (ICCs). ICCs form a network surrounding the myenteric plexus and between-muscle fibres of the muscularis propria of the tubular GI tract. The cell of origin of so-called extra-gastrointestinal stromal tumours (EGISTs) is not known.Aim and methods To study the diversity of gross presentation of GISTs and to critically assess the incidence of EGISTs and their relationship to mural GISTs, a total of 200 neoplasms with typical morphologic and immunohistochemical features of GISTs were reviewed, looking for any degree of association with the muscularis propria of the gut wall.Results There were 130 gastric (65%), 9 duodenal (4.5%), 48 small intestinal (24%), 9 colorectal (4.5%), 1 appendiceal (0.5%) and 3 unclassifiable GISTs (1.5%). Fourteen cases (7%) were initially submitted as EGISTs (four mesenteric, four omental, one pararectal/prostatic, one pelvic/Douglas, one perivesical, one located between root of mesentery and tail of pancreas, one involving the mesentery, omentum and abdominal wall extensively and one located between liver and stomach). After critical re-evaluation of surgical reports and remote clinical history and a careful search for residual muscular tissue from the gut wall in the tumour pseudocapsule (in some cases supported by desmin immunoreactivity), it was possible to reclassify most of these cases (11/14) as either GISTs with extensive extramural growth resulting in loss of contact to the external muscle coat of the gut (8/14) or as metastases from an inoperable GIST (2/14) or from a previously resected deceptively benign tumour (1/14).Conclusion EGISTs are probably rarer than previously reported (1.5% or less in this study). We concluded that most so-called EGISTs represent apparent EGISTs that should have arisen from the outermost muscle coat, but have lost their contact to the point of origin due to extensive extramural growth pattern. From a surgical point of view, it is crucial to document and mark any focal attachment or adhesions to the gut wall noticed during surgery for an apparent EGIST. In contrast to most other neoplasms, GISTs should be defined by virtue of any degree of association with the muscularis propria (no matter how minimal), but not by localisation of the bulk of the tumour.  相似文献   
9.
Osteoporosis is a major public health problem in the Western countries and is projected to have a similar impact in the Middle East. It has been suggested that peak bone mineral density (BMD), a major determinant of osteoporotic fractures later in life, may be lower in this part of the world compared with the Western world. The purpose of the Iranian Multicenter Osteoporosis Study was to determine peak bone mass in a randomly chosen sample of healthy Iranian subjects. A total of 5201 participants (2340 males, mean age 42.7+/-13.8) were recruited based on randomized clustered sampling from all regions of five major cities across the country. In women, peak lumbar BMD (1.182+/-0.127 g/cm2) occurred in the 29- to 33-yr age group, whereas peak total femur BMD (1.006+/-0.126 g/cm2) occurred in the 32- to 36-yr age group. In men, peak lumbar BMD (1.181+/-0.153 g/cm2) and femoral BMD (1.096+/-0.159 g/cm2) both occurred in the 20- to 24-yr age group. When standardized to mg/cm2 units using established formulas, Iranian peak bone mass values are comparable with that of Western countries and are generally higher than that of Eastern Asian and Middle Eastern countries.  相似文献   
10.
Liver hemangioma: US-guided 18-gauge core-needle biopsy   总被引:6,自引:0,他引:6  
Heilo  A; Stenwig  AE 《Radiology》1997,204(3):719
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