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31.
Effect of age and diet on cyclic nucleotide concentrations in the intestinal mucosa of developing rats 总被引:1,自引:0,他引:1
Mucosa isolated from the proximal third of the small intestine of infant rats had much lower cyclic nucleotide concentrations (expressed both per unit wet weight and per unit DNA content) than those determined in the intestinal wall. The steady-state concentrations of both cyclic AMP and cyclic GMP in jejunum showed dramatic increases during the first 5 d post partum. Another increase in cyclic nucleotide concentrations was observed in the isolated mucosa between d 15 and 21. Starvation for 24 h always resulted in lower intestinal cyclic nucleotide concentrations than those of the fed littermates. This effect was more pronounced in younger animals and more evident for cyclic AMP values. Three-week-old rats fed a high carbohydrate diet for 24-48 h exhibited more pronounced elevations in the concentrations of cyclic nucleotides from the jejunal mucosa than did rats fed a high fat diet. 相似文献
32.
Ana L Hermogenes Michael Richardson Arinos Magalhaes Armando Yarleque Edith Rodriguez Eladio F Sanchez 《Toxicon》2006,47(4):490-494
Lachesis venom plasminogen activator (LV-PA) is a 33-kDa serine proteinase isolated from bushmaster (Lachesis muta muta) snake venom, which activates the fibrinolytic system in vitro. This study has examined the effect of the plasma proteinase inhibitor alpha2-macroglobulin (alpha2-M) towards LV-PA and compares it with the effect on tissue type plasminogen activator (t-PA). The proteolytic activity of LV-PA alone or previously incubated with human plasminogen (Plg) on the large molecular mass protein substrates, dimethylcasein (DMC) and fibrinogen (Fg) was completely inhibited by human alpha2-M. However, the synthetic peptides Tos-Gly-Pro-Lys-pNA and H-D-Pro-Phe-Arg-pNA (S-2302) were hydrolyzed with almost no reduction in rate. At pH 7.4 and 37 degrees C the proteinase (0.15 microM over 15 min) interacted with alpha2-M, and each mole of alpha2-M bound 2 mol of enzyme. Sodium dodecyl sulfate gel electrophoresis of reduced samples showed that the interaction of alpha2-M with either LV-PA or t-PA preincubated with Plg resulted in the formation of approximately 90 kDa fragments and high molecular mass complexes (Mr 180 kDa), generated by the incubation mixture (LV-PA or t-PA) and Plg. The data suggest that LV-PA is a direct-type PA and its fibrinolytic effect can be reduced by alpha2-M in vivo. 相似文献
33.
34.
Beyond C4d: Other Complement-Related Diagnostic Approaches to Antibody-Mediated Rejection 总被引:3,自引:0,他引:3
William M. Baldwin III Edward K. Kasper rea A. Zachary Barbara A. Wasowska E. Rene Rodriguez 《American journal of transplantation》2004,4(3):311-318
Complement is a multifunctional system of receptors and regulators as well as effector molecules. Both the pathogenic and diagnostic power of complement is based on the capacity of the complement system to amplify innate and adaptive immunity. This amplification is accomplished through two strategies: (1) enzymatic reactions in the complement cascade, and (2) stimulation of leukocytes, platelets and parenchymal cells through specific receptors or receptor-independent pore formation. The mechanisms by which complement mediates and modifies nonspecific inflammation, antibody-mediated injury and T-cell responses are of particular significance to the pathogenesis of transplant rejection. Understanding the mechanisms by which complement integrates the interactions of leukocytes, platelets and parenchymal cells offers opportunities to further refine the diagnosis of rejection. 相似文献
35.
Robotic-assisted heller myotomy versus laparoscopic heller myotomy for the treatment of esophageal achalasia: multicenter study 总被引:3,自引:0,他引:3
Santiago Horgan M.D. Carlos Galvani M.D. Maria V. Gorodner M.D. Pablo Omelanczuck M.D. Fernando Elli M.D. Federico Moser M.D. Luis Durand M.D. Miguel Caracoche M.D. Jorge Nefa M.D. Sergio Bustos M.D. Phillip Donahue M.D. Pedro Ferraina M.D. 《Journal of gastrointestinal surgery》2005,9(8):1020-1030
Laparoscopic Heller myotomy (LHM) has become the standard treatment option for achalasia. The incidence of esophageal perforation
reported is about 5%–10%. Robotically assisted Heller myotomy (RAHM) is emerging as a safe alternative to LHM. Data comparing
the two approaches are scant. The aim of this study was to compare RAHM with LHM in terms of efficacy and safety for treatment
of achalasia. A total of 121 patients underwent surgical treatment of achalasia at three institutions. A retrospective review
of prospectively collected perioperative data was performed. Patients were divided into two groups: group A (RAHM), 59 patients,
and group B (LHM), 62 patients. All the operations were completed using minimally invasive techniques. There were 63 women
and 58 men, with a mean age of 45 ±19 years (14–82 years). Fifty-one percent of patients in group A and 95% of patients in
group B reported weight loss. Duration of symptoms was equal for both groups. Dysphagia was the main complaint in both groups
(P = NS). There was no difference in preoperative endoscopic treatment in both groups (44% versus 27%, P = NS). Operative
time was significantly shorter for LHM in the first half of the experience (141 ± 49 versus 122 ± 44 minutes, P < .05). However,
in the last 30 cases there was no difference in operative time between the groups (P = NS). Intraoperative complications (esophageal
perforation) were more frequent in group B (16% versus 0%). The incidence of postoperative heartburn did not differ by group.
There were no deaths. At 18 and 22 months, 92% and 90% of patients had relief of their dysphagia. This study suggests that
RAHM is safer than LHM, because it decreases the incidence of esophageal perforation to 0%, even in patients who had previous
treatment. At short-term follow-up, relief of dysphagia was equally achieved in both groups.
Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18,
2005 (oral presentation).
This study was supported in part by a grant provided by Intuitive Surgical, Inc. and Ethicon Endo-Surgery, Inc. 相似文献
36.
The cases of 33 children with hypothalamic-chiasmatic gliomas are reviewed. Radiation therapy produced clinical or radiographic improvement in 11 (46%) of 24 patients. Progression was documented in 18 patients (54%). Overall, the median time to tumor progression was 60 months; it was 70 months in patients who received radiation therapy and 30 months in those who did not (P less than 0.05). Chemotherapy, either given initially or at the time of progression, caused the tumor to respond or to stabilize in 10 patients. Partial resection of the tumor led to improvement in 3 of 12 patients, obviating the need for a shunt in 2 of them; there were no deaths and postoperative morbidity was transient and minimal (diabetes insipidus, intraventricular hemorrhage, and left hemiparesis in one patient each). The 5- and 10-year survival probabilities were 93 and 74%, respectively. Patients with neurofibromatosis had a better prognosis. 相似文献
37.
Ignacio Alvarez Alvarez M.D. Pedro Sanchez Lazo Ph.D. Sofia Ramos Gonzalez Ph.D. J. Pablo Rodrigo Tapia M.D. Faustino Nunez Batalla M.D. Carlos Suarez Nieto M.D. 《American journal of otolaryngology》1997,18(6):375
Purpose: Increasingly, evidence has shown that human papillomavirus (HPV) plays a role in the induction of certain carcinomas. The presence of HPV sequences in 56 previously untreated oral and pharyngolaryngeal carcinomas was examined by the polymerase chain reaction (PCR).Materials and Methods: After DNA extraction, samples underwent 40 replication cycles with specific oligonucleotide primers corresponding to sequences from the E6 open-reading frame of HPV-6b, HPV-16, and HPV-18. To determine the E6 genomic integration, positive samples were processed with specific primers for the corresponding HPV L1 genes. Genomic HPV DNA cloned into PBR 322 was used as positive control.Results: HPV E6 DNA of the 6b and 16 types was detected in 14 patients (25%). The L1 gene was not present.Conclusion: Detected HPV E6 DNA might be integrated into the cell genome in the positive cases as indicated by the absence of the L1 gene-coding for the viral capside. Histological and clinical parameters, such as tumor location, degree of differentiation, stage, recurrence, and survival rates, were unrelated to the presence of HPV. 相似文献
38.
Prospective study of antigenemia,plasma viremia and lymphocytic viremia in HIV-infected hemophiliacs
S. Melón Garcia M. de Oña Navarro C. Rodriguez Pinto M. Fernández Urgellés A. Martinez Gutierrez P. de la Iglesia F. J. Mendez García 《European journal of clinical microbiology & infectious diseases》1995,14(5):400-405
A total of 186 blood samples from 24 HIV-1 seropositive hemophiliac patients, monitored every four months for 29 months, were investigated for the presence of viral antigen in plasma. In addition, peripheral blood mononuclear cells (PBMC) were cultured for HIV-1, using normal PBMC as a target for replication. Antigenemia was detected in 51 % of the patients and from PBMC in 87.5 % of the patients. The incidence of HIV isolation in asymptomatic patients (42.8 %) was similar to that found in symptomatic patients (51.4 %). Patients with opportunistic infections had a higher incidence of lymphocytic viremia (p<0.05). Plasma viremia was closely associated (p<0.05) with low CD4+ counts and infection progression. The persistence of antigenemia was also a marker of a poor clinical course. In treated patients, plasma viremia was the marker that better correlated with the clinical course, and it did not appear during the first nine months of therapy. Zidovudine doses of >500 mg/day significantly lowered the appearance of antigenemia and lymphocytic viremia (p<0.05). 相似文献
39.
Alicia E. Ronco M. Cecilia Sobrero Gustavo D. Bulus Rossini Pablo R. Alzuet Bernard J. Dutka 《Environmental toxicology》1995,10(1):35-39
Toxicity testing of sediment samples from the Rio Santiago and its main tributaries was performed using a battery of tests that included the ECHA dipstick biocide monitor, the MetPad test, the lettuce seed germination and the root elongation test, the nematode test, spot plate test, and the SOS Chromotest. Assessment was carried out on organic extracts, pore water, and direct sediment. Results of bioassays showed toxicity sources from tributaries and canals flowing into the river and areas being degraded by insults from industrial spills. © by John Wiley & Sons, Inc. 相似文献
40.
The records of obese and nonobese victims of blunt trauma were compared to determine if obese individuals are predisposed to a specific injury pattern. Prospectively collected data on 6368 adults admitted to a level I trauma center over a 4-year period were analyzed. Twelve percent (743 patients) met Body Mass Index (weight/height2) criteria for obesity (greater than or equal to 30 kg/m2). The obese group was older (p less than 0.01) and had lower ISSs (p less than 0.05) and higher GCS scores (p less than 0.01). More obese patients were injured in vehicular crashes (62.7% vs. 54.1% [p less than 0.01]). The obese victims were more likely to have rib fractures, pulmonary contusions, pelvic fractures, and extremity fractures and less likely to have incurred head trauma and liver injuries (p less than 0.05). Obese people injured in vehicular crashes had a similar injury pattern with no difference in seating position, direction of impact, seat belt use, and ejection. 相似文献