In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
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Question: Context: Upregulated CD64 expression on neutrophils is the most useful marker for acute bacterial infections and systemic inflammation. However, it is unknown whether CD64 is involved in the pathogenesis of acute pancreatitis (AP). This study was designed to determine whether CD64 is implicated in severe acute pancreatitis (SAP), and thus, is a suitable marker for SAP.', 'SAP was induced in rats with an intraperitoneal injection of L-arginine. CD64 expression in the rat pancreas was determined by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry. Additionally, the CD64 mRNA expression in peripheral blood leukocytes from 21 patients with mild acute pancreatitis (MAP) and 10 patients with SAP was investigated at the time of admission and during remission by qRT-PCR.', 'CD64 mRNA and protein expression in the pancreas was significantly higher in rats with SAP, compared to the controls. The CD64 expression was higher in the patients with SAP than in the patients with MAP. During remission, CD64 mRNA decreased in both the MAP and SAP patients. The area under the curve of CD64 expression for the detection of SAP was superior to both the Ranson and the Acute Physiology and Chronic Health Evaluation II scores.\Question: Is cD64 expression increased in patients with severe acute pancreatitis : clinical significance?

Answer: The CD64 level was significantly increased in correlation with the disease severity in SAP and may act as a useful marker for predicting the development of SAP.


Question: Context: Provocative clinical tests are often performed in the diagnosis of ulnar neuropathy at the elbow (UNE) although the evidence for the usefulness of these tests is limited. The aim of this study was to determine the diagnostic value of provocative clinical tests in the diagnosis of UNE in a relevant spectrum of patients and controls.', "A prospective cohort study was performed in consecutive patients clinically suspected of having UNE. All patients underwent a neurological examination and four commonly used provocative clinical tests (Tinel's test, flexion compression test, palpating for local ulnar nerve tenderness and nerve thickening). Subsequently, in all patients a reference standard test comprising electrophysiological studies and neurosonography was independently assessed.", "192 eligible patients completed the study protocol. UNE was diagnosed in 137 and an alternative diagnosis was made in 55 patients. The sensitivity, specificity, and positive and negative predictive values were as follows: Tinel's test 62%, 53%, 77% and 30%; flexion compression test 61%, 40%, 72% and 29%; palpating for nerve thickening 28%, 87%, 84% and 33%; and palpating for nerve tenderness 32%, 80%, 80% and 32%. Logistic regression and receiver operating characteristic curves showed that the added value of one or more provocative tests over routine clinical examination is minimal.\Question: Is the diagnostic value of provocative clinical tests in ulnar neuropathy at the elbow marginal?

Answer: The diagnostic value of provocative clinical tests in UNE is poor.


Question: Context: Nasopharyngeal carriage of Streptococcus pneumoniae is a prerequisite for invasive disease, but the majority of carriage episodes are asymptomatic and self-resolving. Interactions determining the development of carriage versus invasive disease are poorly understood but will influence the effectiveness of vaccines or therapeutics that disrupt nasal colonization.', 'We sought to elucidate immunological mechanisms underlying noninvasive pneumococcal nasopharyngeal carriage.', 'Pneumococcal interactions with human nasopharyngeal and bronchial fibroblasts and epithelial cells were investigated in vitro. A murine model of nasopharyngeal carriage and an experimental human pneumococcal challenge model were used to characterize immune responses in the airways during carriage.', 'We describe the previously unknown immunological basis of noninvasive carriage and highlight mechanisms whose perturbation may lead to invasive disease. We identify the induction of active transforming growth factor (TGF)-β1 by S. pneumoniae in human host cells and highlight the key role for TGF-β1 and T regulatory cells in the establishment and maintenance of nasopharyngeal carriage in mice and humans. We identify the ability of pneumococci to drive TGF-β1 production from nasopharyngeal cells in vivo and show that an immune tolerance profile, characterized by elevated TGF-β1 and high nasopharyngeal T regulatory cell numbers, is crucial for prolonged carriage of pneumococci. Blockade of TGF-β1 signaling prevents prolonged carriage and leads to clearance of pneumococci from the nasopharynx.\Question: Is density and duration of pneumococcal carriage maintained by transforming growth factor β1 and T regulatory cells?

Answer:
These data explain the mechanisms by which S. pneumoniae colonize the human nasopharynx without inducing damaging host inflammation and provide insight into the role of bacterial and host constituents that allow and maintain carriage.