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Blood components have been implicated as factors which modulate organ injury in acute pancreatitis. To isolate these effects we compared a standardized isolated, blood-perfused, canine pancreas model as described by Herman-Taylor and modified by Cameron with a model using fluosol, a fluorocarbon, as the perfusate. Pancreatitis was induced using partial pancreatic duct obstruction with secretin induced hypersecretion. Twenty-four dogs were randomized into four groups; (1) blood-perfused control (BPC), (2) fluosol-perfused control (FPC), (3) blood-perfused injury (BPI), (4) fluosol-perfused injury (FPI). All glands were observed for 4 h for mean arterial pressure (MAP), weight gain, gross appearance, and venous amylase. Stability was monitored with blood gases and glucose. Specimens were taken at 4 h for light and electron microscopy. Results: BPI preps had a significantly higher vascular resistance at 3 and 4 h compared to FPI preps (3.85 vs 3.26 PRU and 4.8 vs 3.9 PRU, respectively) (P less than 0.002). Edema formation (3+ vs 1+) and venous amylase (18,543 vs 1961) (P less than 0.001) were greater in BPI than FPI preps. Light and electron microscopy confirmed injury but could not quantify it between injury groups. Summary: Hypersecretion and partial ductal obstruction causes a more severe injury in the blood than the fluosol perfused preparation. Changes in the peripheral resistance seen in the blood perfused model lend support to the theory that the primary injury in this model is at the capillary level and is modulated by a blood component.  相似文献   
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Objective: The aim of this study was to determine the prevalence of low back pain (LBP) in a primary care setting population and examine its association with the symptoms of depression and somatization. Methods: This is a cross‐sectional study, utilising a survey carried out in primary health care clinics (PHCs) in Al‐Ain, United Arab Emirates (UAE). A multistage stratified sampling design was used and a representative sample of 1304 UAE nationals aged 18–65 years who attended PHC clinics for any reason were included and 1103 (84.5%) subjects agreed to participate and responded to the questionnaire during a period from June 2001 to January 2002. A specially designed questionnaire with three parts was used for the data collection: socio‐demographic information of the studied subjects, modified version of the Roland‐Morris scale for evaluating back‐related functional disability and SCL‐90 R for depression and somatization subscales was used to assess depressive and somatic symptoms. Results: Of the total number of subjects surveyed (1103), 586 (53.1%) were men and 517 (46.9%) women. The mean age was 34.9 ± 13.4 years for men and 33.5 ± 11.8 years for women. The prevalence of LBP in the studied subjects was 64.7% (95% CI, 60.7–68.5] with 46.7% among men and 53.3% among women. There were a significant differences between the subjects with LBP and without LBP with respect to gender (P < 0.001), body mass index (BMI) (P < 0.001), occupational status (P < 0.001) and living environment (P = 0.016). Functional disability was higher in patients with LBP. Young patients in aged 15–34 years, patients with preparatory/secondary educational level and students showed higher depressive symptoms. A similar pattern was found in patients with somatic symptoms. Factor analysis revealed a strong association between depression and somatization in LBP patients. Conclusions: Functional disability was higher in with LBP. Furthermore, symptoms of depression and somatization are prevalent among LBP patients.  相似文献   
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The community-based course presented is a longitudinal course running through four semesters in the Faculty of Medicine, University of Gezira, Sudan. Students combine their regular work in primary health care centres with attachments to a number of families in Wad Medani town. They continue to visit these families regularly throughout their entire medical course with the aim of studying them and helping them with some of their medical and psychosocial problems.  相似文献   
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A vast majority of the transplant recipients are cytomegalovirus (CMV)-seropositive (R+). We sought to assess variables predictive of CMV infection, specifically in R+ liver transplant recipients. Study patients comprised 182 consecutive liver transplant recipients who survived at least 14 days after transplantation. Surveillance testing was used to detect CMV infection. Pre-emptive therapy was employed for the prevention of CMV disease, however, no antiviral prophylaxis was used for CMV infection. CMV infection developed in 32.5% (38 of 117) of R+ patients, 84.6% (33 of 39) of R-/D+, and 3.8% (1 of 26) of R-/D- patients. In R+ patients, Hispanic race (21.6% vs. 7.8%, P = 0.06), donor CMV seropositivity (73.7% vs. 45.6%, P = 0.005), and hepatocellular carcinoma (23.7% vs. 6.3%, P = 0.05) correlated with a higher risk of CMV infection. In a multivariate model, Hispanic race (OR: 3.5, 95% CI: 1.03-11.6, P = 0.045), donor CMV serostatus (OR: 4.0, 95% CI: 1.6-10.2, P = 0.003) and hepatocellular carcinoma (OR: 5.8, 95% CI: 1.6-20.5, P = 0.006) were all significant independent predictors of CMV infection. The aforementioned variables did not portend a higher risk of CMV infection in R-/D+ patients; donor CMV seropositivity overwhelmed all other risk factors in R- patients (P < 0.00001). In conclusion, CMV-seropositive liver transplant recipients at risk for CMV infection can be identified based on readily assessable variables. Preventive strategies may be selectively targeted toward these patients.  相似文献   
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Abstract  We previously demonstrated that cytomegalovirus (CMV) infection enhanced perivascular inflammation in rat aortic allografts. In this study, we investigated the relationship between the CMV infection load and the magnitude of perivasculitis (chronic rejection) in aortic transplants. Rats received or-thotopic abdominal aortic grafts, different degrees of total body irradiation (TBI) for immunosuppres-sion and CMV inoculation. The spleens of the rats receiving 5 Gy of TBI contained more infectious virus and viral antigens than those of rats receiving 3 Gy of TBI or no TBI. Although the number of inflammatory cells infiltrating the perivascular area was decreased after TBI, CMV infection resulted in increased perivasculitis in rats that received 5 Gy of TBI as compared to non-infected animals. This virus-induced effect was characterized predominantly by an increased T-cell infiltration, including CD4 and CD8 T-cells. It is concluded that an enhanced systemic CMV infection during severe immunosuppressive therapy can accelerate the development of chronic rejection, which seems to be mediated mainly by T-cells.  相似文献   
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This study examined the number of ambulatory care providers treating individuals with the acquired immunodeficiency syndrome who were Medicaid beneficiaries in New York State in 1988 and examined the distribution of this care across various practice settings. The study population was identified retrospectively in the New York State Medical HIV/AIDS Research Data Base and included a cohort of 5535 individuals with the acquired immunodeficiency syndrome who were enrolled in Medicaid in 1988 for at least 6 months after being diagnosed as having the disease and who had at least one ambulatory care encounter during the year. Ambulatory care for the study group was provided by more than 700 hospital or freestanding clinics and more than 3000 private physicians in 1988. Many sites had low caseloads; 47% of the clinics and 68% of the physicians treating this population saw only one or two patients with the acquired immunodeficiency syndrome who were enrolled in Medicaid. More than half the patients in the study group were seen most frequently in clinics for their ambulatory care during 1988. These data provide reassurance that a wide network of providers is involved in the care of patients with the acquired immunodeficiency syndrome who are Medicaid beneficiaries in New York.  相似文献   
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