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1.
Renal vascular reactivity in jaundice 总被引:1,自引:0,他引:1
Obstructive jaundice is associated with a predisposition to hypotension and acute renal failure that may be related to changes in renovascular responsiveness, particularly to norepinephrine (NE). This study was undertaken to investigate changes in vascular response to NE and to determine how these changes are related to prostaglandins. Kidneys from bile duct-ligated (BDL) rabbits (n = 5) were perfused with Krebs' solution at 7.65 ml/min, and the response to varying boluses of NE (0.78 to 6.24 micrograms) was measured as changes in perfusion pressure. When compared with sham-operated control kidneys (n = 8), a significantly blunted response was seen at all doses tested. The NE response was further assessed by measuring force development in mounted segments of main renal arteries (MRAs) (n = 8) and interlobar arteries (ILAs) (n = 6) from BDL rabbits and sham-operated controls (MRA, n = 8; ILA, n = 6). The dose-response curves were significantly depressed in both MRAs and ILAs from BDL animals. In addition, MRAs from sham-operated control animals exhibited decreased response to NE after incubation for 1 hour in jaundiced serum. This attenuated response of MRAs to NE was prevented when indomethacin (5 mg/kg) was given to BDL rabbits before death (n = 9) or when 10(-6)mol/L of indomethacin was added to jaundiced serum during incubation (n = 6). These results indicate that obstructive jaundice induces a decreased vascular contractile response in rabbits to NE and that this effect is mediated by prostaglandins. 相似文献
2.
E.Paul Kirk MB BS J. Santa MD T. Heckler MBA M. Collins MD 《American journal of obstetrics and gynecology》1998,178(6):1222-1228
OBJECTIVE: Our purpose was to assess whether legislative action influenced the role of obstetrician-gynecologists as primary care physicians. STUDY DESIGN: An observational study was performed on the basis of a questionnaire sent to 410 obstetrician-gynecologists and 27 medical directors of managed-care organizations. RESULTS: Of 67% of obstetrician-gynecologists and 96% of medical directors who responded, there was agreement as to the content of primary care, but a minority (38%) of obstetrician-gynecologists identified themselves as primary care providers. A minority of medical directors (35%) felt that obstetrician-gynecologists should serve in that role. Both obstetrician-gynecologists and medical directors felt that legislation had little impact. CONCLUSION: The reticence of obstetrician-gynecologists to assume a major role in primary care appears to be the result of an uneasiness with accepting a more comprehensive role in patient management and gatekeeping. They appear comfortable with the more traditional roles but feel that training and experience has not prepared them well for the management of more complex medical problems. (Am J Obstet Gynecol 1998;178:1222-8.) 相似文献
3.
Fernanda Coutinho Luiz Claudio de Santa Maria 《Macromolecular chemistry and physics.》1992,193(7):1739-1744
The effect of ethyl benzoate (EB), diisobutyl phthalate (DIBP), dibutyl ether (DBE) and triethoxy(phenyl)silane (EPS) as third components on the propene polymerization with the catalyst systems δ-TiCl3/AlCl(C2H5)2 and δ-TiCl3/Al(C2H5)3 was investigated. The influence of external donors on the isotacticity, catalyst activity and average molecular weight (M v) was tested. If external donors are employed, M v decreases, the insoluble fraction in boiling isooctane increases and the catalyst activity is strongly influenced by the mole ratio external donor/TiCl3. The results indicate that all external donors employed have the same qualitative effect on catalytic active centers. 相似文献
4.
5.
Glaucomatous optic neuropathy. 总被引:15,自引:0,他引:15
6.
From 1969 through 1977, 210 patients with Stage IB carcinoma of the uterine cervix were treated at University of Maryland Hospital. Fifty-six patients were treated by radical hysterectomy (S), 136 patients were treated by a full course of radiation therapy (RT) only and 18 patients received radiation treatment following radical surgery (S + RT). The 5-year determinate survival rates were almost the same in the S group and RT alone group (79% and 77%, respectively). The 5-year determinate survival rate in the S + RT group was 50%, which was statistical significantly lower than S alone or RT alone groups (P less than 0.05). Several prognostic factors were analyzed in the radiated patients: the size of the primary lesion, location of the lesion within the cervix, tumor grade, age of the patients at the time of diagnosis, and complete blood count nadir during the course of radiation treatment. The only factor found to influence the prognosis was the size of the primary tumor. The patients with smaller tumors had a better prognosis; the absolute and determinate 5-year survival rates were 80% and 82%, while the absolute and determinate survival rates in the large, fungating tumor replacing the entire cervix were 56% and 60%, respectively (P less than 0.001). The complication rate was 22% in the RT alone, 22% in the S + RT, and 25% in the S alone groups. 相似文献
7.
Kerry E. Goetz Melissa J. Reeves Shaina Gagadam Delphine Blain Chelsea Bender Cara Lwin Amelia Naik Santa J. Tumminia Robert B. Hufnagel 《American journal of medical genetics. Part C, Seminars in medical genetics》2020,184(3):828-837
Genetic testing in a multisite clinical trial network for inherited eye conditions is described in this retrospective review of data collected through eyeGENE®, the National Ophthalmic Disease Genotyping and Phenotyping Network. Participants in eyeGENE were enrolled through a network of clinical providers throughout the United States and Canada. Blood samples and clinical data were collected to establish a phenotype:genotype database, biorepository, and patient registry. Data and samples are available for research use, and participants are provided results of clinical genetic testing. eyeGENE utilized a unique, distributed clinical trial design to enroll 6,403 participants from 5,385 families diagnosed with over 30 different inherited eye conditions. The most common diagnoses given for participants were retinitis pigmentosa (RP), Stargardt disease, and choroideremia. Pathogenic variants were most frequently reported in ABCA4 (37%), USH2A (7%), RPGR (6%), CHM (5%), and PRPH2 (3%). Among the 5,552 participants with genetic testing, at least one pathogenic or likely pathogenic variant was observed in 3,448 participants (62.1%), and variants of uncertain significance in 1,712 participants (30.8%). Ten genes represent 68% of all pathogenic and likely pathogenic variants in eyeGENE. Cross‐referencing current gene therapy clinical trials, over a thousand participants may be eligible, based on pathogenic variants in genes targeted by those therapies. This article is the first summary of genetic testing from thousands of participants tested through eyeGENE, including reports from 5,552 individuals. eyeGENE provides a launching point for inherited eye research, connects researchers with potential future study participants, and provides a valuable resource to the vision community. 相似文献
8.
Silencing of Fas, but not caspase-8, in lung epithelial cells ameliorates pulmonary apoptosis, inflammation, and neutrophil influx after hemorrhagic shock and sepsis 总被引:6,自引:0,他引:6 下载免费PDF全文
Perl M Chung CS Lomas-Neira J Rachel TM Biffl WL Cioffi WG Ayala A 《The American journal of pathology》2005,167(6):1545-1559
Apoptosis and inflammation play an important role in the pathogenesis of direct/pulmonary acute lung injury (ALI). However, the role of the Fas receptor-driven apoptotic pathway in indirect/nonpulmonary ALI is virtually unstudied. We hypothesized that if Fas or caspase-8 plays a role in the induction of indirect ALI, their local silencing using small interfering RNA (siRNA) should be protective in hemorrhage-induced septic ALI. Initially, as a proof of principle, green fluorescent protein-siRNA was administered intratracheally into transgenic mice overexpressing green fluorescent protein. Twenty-four hours after siRNA delivery, lung sections revealed a significant decrease in green fluorescence. Intratracheally administered Cy-5-labeled Fas-siRNA localized primarily in pulmonary epithelial cells. Intratracheal instillation of siRNA did not induce lung inflammation via toll-like receptor or protein kinase PKR pathways as assessed by lung tissue interferon-alpha, tumor necrosis factor-alpha, and interleukin (IL)-6 levels. Mice subjected to hemorrhagic shock and sepsis received either Fas-, caspase-8-, or control-siRNA intratracheally 4 hours after hemorrhage. Fas- or caspase-8-siRNA significantly reduced lung tissue Fas or caspase-8 mRNA, respectively. Only Fas-siRNA markedly diminished lung tissue tumor necrosis factor-alpha, IL-6, IL-10, interferon-gamma, IL-12, and caspase-3 activity. Fas-siRNA also preserved alveolar architecture and reduced lung neutrophil infiltration and pulmonary epithelial apoptosis. These data indicate the pathophysiological significance of Fas activation in nonpulmonary/shock-induced ALI and the feasibility of intrapulmonary administration of anti-apoptotic siRNA in vivo. 相似文献
9.
10.
Laura McGillis Nimish Mittal Daniel Santa Mina Joyce So Medha Soowamber Aliza Weinrib Leslie Soever Dmitry Rozenberg Louis Liu Yvonne Tse Joel Katz George S Charames Kieran Murphy Peter Vadas Maxwell P Slepian Scott Walsh Lindsay Wilson Arnon Adler Alyssa Franzese Laura Hussey Dayna‐Lynn Nevay Juan Guzman Hance Clarke 《American journal of medical genetics. Part A》2020,182(3):484-492
The new 2017 diagnostic criteria for hypermobile Ehlers–Danlos Syndrome (hEDS) provide a framework for diagnosing hEDS but are more stringent than the previous Villefranche criteria. Our clinical experience at the GoodHope EDS clinic was that the 2017 criteria left many highly symptomatic patients without a diagnosis of hEDS. We conducted a retrospective cohort study to confirm our clinic experience and assess the accuracy of the 2017 diagnostic criteria for hEDS in patients who had a previous hEDS diagnosis based on the Villefranche criteria. Our study found that 15% (n = 20 of 131) of patients with a prior diagnosis of hEDS met the 2017 diagnostic criteria, and many of the traits used to distinguish hEDS were not significantly more frequent in patients who met 2017 criteria versus those who did not. In both groups objective systemic manifestations were found less frequently than subjective systemic manifestations. Beighton score (BS) as assessed by primary care practitioner was found to be higher than assessment by EDS practitioner in 81% (n = 74 of 91) of cases. Generalized joint hypermobility was confirmed in only 46% (n = 51 of 111) of patients who had a previous diagnosis of hEDS. Higher BS did not correlate with increased number of systemic manifestations in our cohort. Common comorbidities of hEDS were found with similar frequency in those who met 2017 criteria and those who did not. Based on our cohort, the 2017 hEDS diagnostic criteria require refinement to improve its diagnostic accuracy. 相似文献