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61.
BACKGROUND: The role of cholinergic pathways in the pathogenesis of bile-pancreatic duct ligation (BPDL)-induced acute pancreatitis in rats remains controversial. We hypothesized that cholinergic stimulation exacerbates acute pancreatic inflammation in the presence of duct obstruction. METHODS: We studied 34 rats divided into 5 groups as follows: (1) sham operation; (2) BPDL; (3) BPDL with duodenal bile-pancreatic juice (BPJ) replacement fresh from a donor rat; (4) BPDL with BPJ replacement as in 3 above, and carbachol (CCh) 5 ug/h subcutaneously; or (5) CCh 5 ug/h subcutaneously only. Rats were killed after 6 hours. RESULTS: The P value was less than .05 by analysis of variance. Pancreatic morphologic changes and zymogen fraction hyperamylasemia seen with duct ligation (2 vs. 1) were ameliorated significantly by duodenal BPJ replacement (3 vs. 2), but not when exogenous CCh was administered (4 vs. 3), whereas CCh alone showed no significant changes compared with sham (5 vs. 1). CONCLUSIONS: Cholinergic stimulation and duct obstruction synergistically amplify acinar hyperstimulation and exacerbate acute pancreatitis.  相似文献   
62.
Ras genes can be altered by point mutations at critical portions of their coding regions to acquire transforming ability in vitro. These point mutations have been detected in a variety of human malignancies. However, their relevance for the clinical and biologic behavior of the subgroups of patients exhibiting these mutations in unclear. We analyzed 100 patients with childhood acute lymphocytic leukemias (ALLs) for point mutations of exons 1 and 2 of all three ras genes (H-ras, K- ras, and N-ras) by polymerase chain reaction and a combination of oligonucleotide hybridization and direct DNA sequencing. A 6% incidence of N-ras gene mutations was detected, all of which occurred at different nucleotides of codons 12 or 13 of N-ras. When correlating presence of ras mutations with the clinical and biologic features and the clinical outcome of these cases, a significantly higher risk for hematologic relapse (P = .01) and a trend toward a lower rate of complete remission (P = .07) was noted. The two groups did not differ in any of the known high-risk factors of ALL. These results suggest that presence of an N-ras mutation in children with ALL may be an independent predictor for worse clinical outcome and therefore may have therapeutic implications; further studies to confirm these findings are required because of the small number of patients with N-ras mutations.  相似文献   
63.
    

Ethnopharmacological relevance

Gouania longipetala leaves are commonly used in folkloric medicine in Africa and other parts of the world for treatment of edema, febrifuges, veneral diseases, lumbago, heart diseases, diabetes mellitus malaria, etc. This study therefore evaluated safety profile of the methanol leaf extract of the plant using acute and sub-chronic studies in rat model.

Materials and methods

Acute toxicity test of the plant lasted for 48 h with oral administration of graded doses (100–4000 mg/kg) of Gouania longipetala extract (GLE) in rats. The rats were observed for signs of toxicity and death. The sub-chronic toxicity was evaluated by administration of different doses (2.5, 5 and 10 mg/kg) of GLE daily in feed for 90 days. On days, 30, 60 and 90, blood samples collected from the retro-orbital plexus of the eye of the rats were used for evaluation of serum biochemistry, hematology, lipid peroxidation and in vivo antioxidant activities. Histopathological evaluations of the kidney, liver, lungs and heart were also done.

Results

The acute toxicity test revealed no observable signs of toxicity or morbidity. Sub-chronic study showed that GLE significantly (p<0.05) increased relative liver weight on day 90 at 10 mg/kg. There were no significant variations in the hematological parameters of both GLE treated and untreated rats. The extract significantly (p<0.05) reduced total cholesterol, triglycerides, very low density lipoproteins and increased high density lipoproteins which was more prominent on day 90 at the dose of 10 mg/kg. The extract significantly (p<0.05) increased liver enzyme markers at the doses used. GLE also significantly (p<0.05) increased serum urea at the dose of 10 mg/kg on day 90. The extract caused dose-dependent and significant (p<0.05) increase in superoxide dismutase and decrease in malondiadehyde. Histopathological studies revealed degenerative changes in the kidney and liver.

Conclusion

The results of the study suggest that Gouania longipetala is well tolerated in short term therapies, but may have long term toxic effects on the kidney and liver.  相似文献   
64.
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 BACKGROUND  The Impella pump has emerged as a promising tool in patients with cardiogenic shock (CS). Despite its attractive properties, there are scarce data on the specific clinical setting and the potential role of Impella devices in CS patients from routine clinical practice.  METHODS  This is an observational, retrospective, single center, cohort study. All consecutive patients with diagnosis of CS and undergoing support with Impella 2.5®, Impella CP® or Impella 5.0® from April 2015 to December 2020 were included. Baseline characteristics, management and outcomes were assessed according to CS severity, age and cause of CS. Main outcome measured was in-hospital mortality.  RESULTS  A total of 50 patients were included (median age: 59.3 ± 10 years). The most common cause of CS was acute coronary syndrome (ACS) (68%), followed by decompensation of previous cardiomyopathy (22%). A total of 13 patients (26%) had profound CS. Most patients (54%) improved pulmonary congestion at 48 h after Impella support. A total of 19 patients (38%) presented significant bleeding. In-hospital mortality was 42%. Among patients with profound CS (n = 13), five patients were previously supported with venoarterial extracorporeal membrane oxygenation. A total of eight patients (61.5%) died during the admission, and no patient achieved ventricular recovery. Older patients (≥ 67 years, n = 10) had more comorbidities and the highest mortality (70%). Among patients with ACS (n = 34), 35.3% of patients had profound CS; and in most cases (52.9%), Impella support was performed as a bridge to recovery. In contrast, only one patient from the decompensated cardiomyopathy group (n = 11) presented with profound CS. In 90.9% of these cases, Impella support was used as a bridge to cardiac transplantation. There were no cases of death.  CONCLUSIONS  In this cohort of real-life CS patients, Impella devices were used in different settings, with different clinical profiles and management. Despite a significant rate of complications, mortality was acceptable and lower than those observed in other series.  相似文献   
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66.
STUDY OBJECTIVES: We define the predictive value of parents' computer-based report for history and physical signs of dehydration for a primary outcome of percentage of dehydration (fluid deficit) and 2 secondary outcomes: clinically important acidosis and hospital admission. We also sought to compare the reports of physical signs related to dehydration made by parents and nurses. METHODS: We performed a prospective observational trial in an urban pediatric emergency department. A convenience sample of parents completed a computer-based interview covering historical details and physical signs (ill appearance, sunken fontanelle, sunken eyes, decreased tears, dry mouth, cool extremities, and weak cry) related to dehydration. Nurses independently completed an assessment of physical signs for enrolled children. The primary outcome was the degree of dehydration (fluid deficit), which was defined as the percentage difference between initial ED weight and stable final weight after the illness. Secondary outcomes included clinically important acidosis (defined as a serum CO(2) value of 相似文献   
67.
Tuberculosis is a public health problem. The most common presentation is pulmonary disease. The diagnosis of any extrapulmonary forms are quite difficult. Clinical manifestations of gastrointestinal tuberculosis are non-specific and compatible with pathologies such as inflammatory bowel disease, advanced ovarian cancer, deep mycosis, yersinia infection and amebomas. Abdominal form is located at 6th place of the extrapulmonary forms, after lymphatic, genitourinary, osteoarticular, miliary and meningeal infections. Eventually, 25 to 75% of patients with abdominal tuberculosis will require surgery. These procedures should be limitated with the purpose to preserve small bowel. Resection should be limitated for complicated cases. The surgical indications include: Intestinal occlusion (15-60%), perforation (1-15%), abscesses and fistulas (2-30%) and hemorrhage (2%). CONCLUSIONS: In most of the cases, the diagnosis of peritoneal or intestinal tuberculosis is made during a laparoscopy or laparotomy even during surgery performed by different purposes. Excessive manipulation of the intraabdominal organs may produced unexpected bowel lesions, increasing morbidity and mortality. Medical treatment is highly effective in the resolution of moderate complications such as bowel obstruction. Resectional procedures should be reserved for complications like perforation, bleeding or stenosis non-suitable for stricturoplasty.  相似文献   
68.
Acute myocardial infarction during pregnancy is considered to be associated with approximately 50% mortality of both mother and fetus. However, there are not enough data regarding the role of acute myocardial ischemia. We present a 36-year-old, pregnant, white female who was admitted twice at 18 and 20 weeks of gestation with acute myocardial ischemia. Cardiac catheterization revealed 70–80% stenosis of the mid left anterior descending artery (LAD) with normal antegrade flow and very good retrograde filling of the LAD from distal collaterals of the right coronary artery. Therefore, due to angiographic suggestion of protected LAD territory, we recommended medical therapy and scheduled a vaginal delivery that was successfully completed without cardiovascular complications. A stress thallium test performed 6 months later was normal, supporting our clinical judgment. In conclusion, every case of a pregnant woman with coronary insufficiency should be treated according to individual coronary anatomy and blood supply to the territory of the diseased artery, and should not be based on the old data in the literature. The decision for revascularization prior to delivery versus medical therapy, or Caesarean section versus natural delivery, should be made by a team of a cardiologist and an obstetrician.  相似文献   
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