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ObjectiveThyroid nodules are common, being detected in 19% to 67% of the population. A fine needle aspiration biopsy (FNAB) is recommended for suspicious thyroid nodules to rule out malignancy; however, the procedure can be painful for subsets of patients. It remains unclear what factors are more likely to be associated with pain during FNAB. This literature review aimed to investigate patient-, procedure-, and analgesic-related factors that affect pain levels during thyroid nodule FNAB.MethodsPredefined inclusion and exclusion criteria were set to search the Embase, MEDLINE, CINAHL, and Cochrane databases. The articles evaluating the factors affecting pain during FNAB were assessed for inclusion. The primary outcome of interest was scores evaluating pain level during FNAB.ResultsTwenty-two studies were included. The studies were a mix of cohort studies, randomized controlled trials, and clinical controlled trials. Under patient-related factor, nodule calcification was associated with increasing pain. The procedure-related factors potentially increasing pain included the number of needle passes and utilization of the aspiration technique (as opposed to capillary action), perpendicular needle placement (as opposed to parallel), and not using safety devices. Larger needle size, type of biopsy, operator expertise, and patient education did not appear to be correlated with pain. Subcutaneous lidocaine appeared to provide better pain relief than a topical analgesic.ConclusionWith increasing use of FNAB as the diagnostic test of choice for assessing thyroid nodules, understanding patient-, procedure-, and analgesic-related factors associated with optimal patient satisfaction is imperative. 相似文献
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Recent interest in the analysis of glycinebetaine in algae has stimulated the search for improved methods of assaying betaines. A method based on high-performance liquid chromatographic (HPLC) separation using commercial columns and guard columns is described in detail for the newcomer. The methods is sensitive, reproducible and flexible enough to allow for minor differences among different HPLC pump systems. 相似文献
664.
Details of mouth formation in normal and exogastrulated Pisaster ochraceus larvae have been studied by light microscopy and transmission and scanning electron microscopy. As the archenteron begins to bend, the cells in the presumptive mouth region dissociate and migrate into the blastocoele where they become mesenchyme cells. This leaves a defect in the “blind” endodermal tube, which is covered by a basal lamina. Subsequently this exposed basal lamina bulges to form a blister which appears to extend across the blastocoele to make contact with spikelike projections from the future stomodeal region of the ectoderm. Mesenchyme cell processes are associated with both the basal lamina blister and the ectoderm in this region and may provide both motive power and guidance for contact. Shortly after contact is made the blister of basal lamina from the endoderm fuses with the basal lamina of the ectodermal cells and the ectoderm begins to invaginate. At this time the lateral walls of the presumptive oesophagus are largely formed of naked basal lamina with some loosely associated cells on the endodermal side. Eventually the lateral walls of the proximal part of the oesophagus become cellular, giving rise to an epithelium. A cell plug located between the stomodeum and oesophagus persists for some time before finally breaking down to complete the larval digestive tract. Experiments with exogastrulae suggest that many of these developmental patterns are determined before gastrulation. 相似文献
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Eggs of the asteroid Pisaster ochraceus demonstrate cortical granules, a thick vitelline membrane, and a poorly stained jelly coat similar to that seen on the eggs of other echinoderms. When fixed in the presence of alcian blue the jelly coat is seen to be made up of three regions, an inner layer consisting of a meshwork of fibres, a middle layer of thicker fibres, and a dense outer layer. At fertilization the cortical granules release their contents into the potential space between the vitelline layers and a low fertilization membrane consisting of the vitelline layer and a dense component of the corticle granule is formed. Initially the remaining contents of the corticle granules form an amorphous hyaline layer that fills the space between the plasma membrane and the fertilization membrane. At hatching a distinct hyaline layer is present. It persists at least to the bipinnaria stage and consists of four distinct layers. A similar layer is also located over much of the early embryonic endoderm but is lost from the regions involved in the formation of the mesenchyme cells, coelom, and mouth just before these events take place. Numerous large clear vesicles are located in the apex of all cells associated with a hyaline layer. Where the hyaline layer is lacking, only scattered vesicles are present suggesting that the vesicles may be involved in maintenance of the layer. Attempts to identify elements of the hyaline layer by immunofluorescence demonstrated that it appears to bind both antisera and control sera in a nonspecific manner. 相似文献
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Catheter encrustation was studied in a group of long-stay hospital patients using both latex and silicone catheters. Moisture accounted for 80% by weight of the encrusted material with both catheters. Of the dry weight 90% was composed of protein, calcium, phosphorus, magnesium and uric acid. No relationship was found between the amounts of these substances in the urine and in the encrusted material. High levels of calcium, phosphorus and magnesium were found in the encrusted material from patients infected with Proteus organisms. No direct relationship was found between the duration of catheter drainage and the degree of encrustation, and there was a variation in patient susceptibility to encrustation irrespective of the catheter material. There was significantly less encrustation associated with silicone catheters. 相似文献
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Magd El-Morsi Awad Montaser Fawzy Abdel-Monaim 《Archives Of Phytopathology And Plant Protection》2013,46(6):652-659
The efficiency of some commercial biological control agents (BCAs), Bio Zaid and Bio Arc, and resistance inducers chemicals (RICs) (salicylic acid and Bion) on management of cucumber powdery mildew, caused by Sphaerotheca fuliginea, was evaluated in vitro and in vivo. In vitro experiments revealed that application of the tested BCAs and RICs significantly reduced the disease severity, number of conidia per leaf area unit (cm) and reduced germination of conidiospores of the causal pathogen. Under field conditions, application of BCAs and RICs caused significant decrement in the disease severity with significant increment in the fruit yield compared with check treatments. On the average, application of Bion recorded the highest values, either in reducing the disease severity or in raising the average fruit yield followed by Bio Arc. On the other hand, applying salicylic acid (SA) recorded, on the average, the lowest efficiency in reducing disease severity and low values of fruit yield in both growing seasons. 相似文献