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121.
BACKGROUND: The mechanism of acinar cell death in human chronic pancreatitis (CP) remains largely unexplored. Previous studies have demonstrated the role played by apoptosis and necrosis in experimental pancreatitis; however, their relationship with the progression of CP remains unknown. The present study was carried out to elucidate the role and extent of apoptosis in CP tissues with different histopathological scores and to examine the possible apoptotic pathway involved. METHODS: Pancreatic tissues (25 CP patients) that had been histopathologically graded (I-III) and ten normal pancreatic tissue samples were evaluated for apoptosis by DNA fragmentation and an in situ TUNEL assay. The expression of various apoptotic and antiapoptotic markers in the tissues were studied by immunohistochemistry and Western blotting. To elucidate the role of the mitochondria in acinar cell death, the mitochondrial membrane potential (DeltaPsim) and ATP levels were determined by flow cytometry and a luminometer. RESULTS: The presence of DNA fragmentation and apoptotic nuclei in all CP tissues confirmed the presence of apoptosis. The apoptotic index in CP tissue ranged from 0.09% to 0.86% +/- 0.02% and was highest in grade II (0.7 +/- 0.04%) tissues. Differential upregulation of the apoptotic mediators p53, Bax, cytochrome c, and caspase-3 and -9, and downregulation of antiapoptotic Bcl-2, was observed in CP. DeltaPsim on the order of 1.2-to 2.2-fold and ATP depletion in the range of 23%-84% in CP tissues was observed. CONCLUSIONS: Apoptosis plays an important role both in the initial stages and during the progression of CP, as evident in all tissue grades. Increased DeltaPsim, loss of ATP, and activation of caspases suggests the involvement of intrinsic pathways.  相似文献   
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Nasal mucus clearance (NMC) was studied in seventy patients with chronic maxillary sinusitis. Forty-five patients were treated with oral administration of bromhexine tablets along with oral antibiotics and nasal decongestants. Twenty-five patients received the same treatment but without bromhexine to evaluate the results. NMC was also studied in hundred healthy controls.  相似文献   
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Tumor necrosis factor (TNF)-alpha is thought to play an important role in wasting; but TNF-alpha levels have not been consistently found to be high in AIDS wasting. We conducted this study to determine any correlation between TNF-alpha levels and wasting in HIV-positive patients in a developing country. TNF-alpha levels were measured in four groups of patients: Group 1, HIV/AIDS with wasting (n = 25); group 2, HIV/AIDS without wasting (n = 47); group 3, HIV-negative patients with tuberculosis with wasting (n = 25); and group 4, healthy controls (n = 25). Wasting was defined as a body bass index (BMI) 相似文献   
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A core social-psychological question is how cultural stereotypes shape our encounters with other people. While there is considerable evidence to suggest that unexpected targets-such as female airline pilots and male nurses-impact the inferential and memorial aspects of person construal, it has yet to be established if early perceptual operations are similarly sensitive to the stereotype-related status of individuals. To explore this issue, the current investigation measured neural activity while participants made social (i.e., sex categorization) and non-social (i.e., dot detection) judgments about men and women portrayed in expected and unexpected occupations. When participants categorized the stimuli according to sex, stereotype-inconsistent targets elicited increased activity in cortical areas associated with person perception and conflict resolution. Comparable effects did not emerge during a non-social judgment task. These findings begin to elucidate how and when stereotypic beliefs modulate the formation of person percepts in the brain.  相似文献   
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Severe acute pancreatitis (SAP) is associated with significant morbidity and mortality. The majority of deaths related to SAP are the result of infectious complications. Although bacterial infections are most commonly encountered, fungal infections are increasingly being recognized. Candida is the most common fungal infection. The occurrence of fungal infection in patients with acute pancreatitis adversely affects the clinical course, leading to a higher incidence of systemic complications, and possibly mortality as well. Important risk factors for fungal infection in patients with acute pancreatitis include broad-spectrum antibiotics, prolonged hospitalization and surgical/endoscopic interventions, use of total parenteral nutrition, and mechanical ventilation. Patients with higher severity of pancreatitis are at a greater risk. The pathogenesis of fungal infection in patients with acute pancreatitis is multifactorial. Translocation of microorganisms across the gut epithelium, lymphocyte dysfunction, and the virulence of the invading microorganisms play important roles. Histological demonstration of fungi remains the gold standard of diagnosis, but a positive biopsy is rarely obtained. The role of biomarkers in the diagnosis is being investigated. As early diagnosis and treatment can lead to improved outcome, a high index of suspicion is required for prompt diagnosis. Limiting the use of broad-spectrum antibiotics, early introduction of enteral nutrition, and timely change of vascular catheters are important preventive strategies. The role of antifungal prophylaxis remains controversial. Surgical necrosectomy with antifungal therapy is the most widely used treatment approach. Clinical trials on antifungal prophylaxis are needed, and indications for surgical intervention need to be clearly defined.  相似文献   
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Abstract Background:  Nonoperative management is being increasingly employed in the management of blunt hepatic injuries. Patients and Methods:  We analyzed patients with complex hepatic injuries over a period of 10 years (1996–2006). Results:  Two hundred and ten patients with blunt hepatic injury were admitted and 103 patients had complex liver injuries. The predominant mode of injury was road traffic accidents in 91.2%. The grade distribution of liver injuries was grade III (72.8%), grade IV (23.3%) and grade V (4.9%). Twenty-four patients (23.3%) underwent surgery for persistent hemodynamic instability, persistent fall in hemoglobin level, bile leaks and intra-abdominal collection with sepsis. Associated intra-abdominal injuries were present in 19.4%, and 58.4% had associated extra-abdominal injuries. The operative procedures included hepatectomy (1), suture hepatorraphy (12), T-tube drainage for bile duct injuries (5), perihepatic sponge and gel foam packing (9), liver abscess drainage (3), and resection and debridement of liver tissue in six patients. The mortality and morbidity in this series was 10.7 and 56.4%, respectively. Multiorgan failure was present in 5, single organ failure in 37, sepsis in 24, biliary complications in 16 and intra-abdominal collection in 17 patients. Endoscopic management for bile leaks was performed in five patients, image-guided pig-tail drainage for abscesses in 11 patients, while angioembolization was done in two patients for right hepatic artery bleed. The mortality was not significantly different in surgical and nonoperative groups but operated patients had significantly higher morbidity. Conclusions:  Complex liver injuries can be managed successfully with conservative treatment in majority, with low mortality and acceptable morbidity. Surgery is reserved for selected indications.  相似文献   
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