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41.
The routine availability of murine models of various cerebral circulatory disorders requires characterization of the regulation of cerebral artery tone in the mouse. Using vasoconstrictors and vasodilators with known efficacy in the cranial circulation of other species, we determined the pharmacological properties of the isolated pressurized mouse middle cerebral artery (MCA). The maximal pressure-induced myogenic constriction in isolated mouse MCA was 20.6+/-2.4%. Inhibition of nitric oxide (NO) and endothelin-1 (ET-1) altered the extent of pressure-induced myogenic tone. Isolated mouse MCA failed to either constrict or relax to 5-hydroxytryptamine (5-HT) and histamine; other vasoconstrictors demonstrated the following rank order of efficacy: ET-1>phenylephrine>U-46619. The rank order of endothelium-dependent vasodilator efficacy was bradykinin (BK)>acetylcholine (ACh)>substance P. The constriction produced by phenylephrine (PE) required a smaller increase in intracellular Ca(2+) elevation compared to constriction of a similar magnitude produced by membrane depolarization with potassium chloride (KCl). Pressure-induced myogenic tone (20-80 mm Hg) in mouse MCA was associated with smooth muscle cell membrane depolarization (-52.6+/-0.9 to -37.3+/-1.75 mV). Pressure-induced myogenic tone occurred with a smaller change in membrane potential compared to tone of a similar magnitude produced with KCl (-43.37+/-2.66 vs. -29.47+/-1.05 mV). The mouse MCA has a pharmacological profile that is distinct from other species including humans; however, similar to findings in other cerebral arteries, the mouse MCA shows intracellular sensitization to Ca(2+) following receptor activation. 相似文献
42.
Silverman DH Delpassand ES Torabi F Goy A McLaughlin P Murray JL 《Cancer treatment reviews》2004,30(2):165-172
Anti-CD20 antibodies radiolabeled with I-131 tositumomab (Bexxar) or Y-90-Ibritumomab tiuxetan (Zevalin), are similarly efficacious in treating chemotherapy-refractory non-Hodgkin's lymphoma. The relative merits of both radioimmunoconjugates with respect to practical issues, including radiation exposure risk, the advantages and disadvantages of the respective isotopes and other parameters that could affect a patient's quality of life are also important. I-131-labeled antibody treatment often requires inpatient hospitalization due to the inherent risk of exposure from gamma emissions, and patients and families should follow detailed instructions to prevent undue exposure. Other issues relevant to patients and medical staff include: (1) the need for dosimetry to calculate effective therapeutic doses of I-131-labeled anti-B1 (Bexxar) compared with the lack of correlation of dosimetry with marrow toxicity for IDEC-Y2B8 (Zevalin), (2) determining the acute and long-term toxic effects of each agent, (3) time commitments for nuclear medicine staff and patients along with the relative ease of administration, and (4) cost considerations. A more challenging future issue will be to determine the optimal use of Bexxar and Zevalin alone and in combination in ways that will significantly affect patient outcome without compromising quality of life. The recent demonstration of significant response rates in patients having chemotherapy-refractory Non-Hodgkin's Lymphoma (NHL) using both on I-131- and Y-90-labeled anti-CD20 antibodies with minimal toxicity has stimulated comparison of I-131 tositumomab (Bexxar) and Ibritumomab tiuxetan (Zevalin) in terms of radiation safety requirements, the advantages and disadvantages of both radionuclides, and quality-of-life (QOL) issues. Therefore, in this review, we attempt to compare the relative merits of (Bexxar and Zevalin) and address important practical considerations that may influence patient and physician choices regarding treatment using these agents. 相似文献
43.
The purpose of the present study was twofold: (1) to investigate how many diabetic patients and types of cases that are treated with dental implants in our clinic; and (2) assess the outcome of such treatment. Medical records from 782 patients were examined in patients treated by the Br?nemark method for partial or total edentulism with implant supported bridges. From these records, 25 patients (3.2%) with diabetes before implant treatment (136 implants) were identified and further studied with respect to age, gender, type of diabetes, treated jaw, degree of edentulism, bone graft, implant survival, periimplant inflammation, bleeding on probing, and radiographic bone loss. Furthermore, the patients' opinion about the outcome of the treatment was registered. The implant success rate was 96.3% during the healing period and 94.1% 1 year after surgery. Of all 38 bridges, one was lost. Few complications occurred and all patients, except for one, were satisfied with the treatment. Today, diabetic patients are being treated successfully for all types of edentulism, including bone-grafting treatment. Diabetics that undergo dental implant treatment do not encounter a higher failure rate than the normal population, if the diabetics' plasma glucose level is normal or close to normal as assessed by personal interviews. 相似文献
44.
Shidfar F Keshavarz A Jallali M Miri R Eshraghian M 《International journal for vitamin and nutrition research. Internationale Zeitschrift für Vitamin- und Ern?hrungsforschung. Journal international de vitaminologie et de nutrition》2003,73(3):163-170
BACKGROUND: Control of hyperlipidemia is vital in patients with cardiovascular disease (CVD). Omega-3 fatty acids (n-3FAs) have desirable effects on serum triglyceride (TG) levels, thrombosis, and arrhythmia, but lead to increases in serum low-density lipoprotein (LDL) and apo-B as well. OBJECTIVE: To determine and compare the effects of administration of n-3FAs, vitamin C (VitC) and n-3FAs + VitC on the serum levels of LDL, apoB, other serum lipids, and malondialdehyde (MDA). The present study was performed in Tehran University of Medical Sciences from 2000 to 2001. DESIGN: In a double-blind, placebo trial of parallel design, 68 hyperlipidemic patients [total cholesterol (TC) and TG greater than 200 mg/dL] were randomly assigned to receive daily 500 mg VitC, 1 g n-3FAs, 500 mg VitC + 1 g n-3FAs, or placebo (control) for 10 weeks. Fasting blood samples were collected at the beginning and at the end of the period. TG, TC, LDL-cholesterol-C (LDL-C), and high-density lipoprotein-cholesterol (HDL-C) were measured enzymatically, VitC and MDA colorimetrically, and apo-B and apo-A-I immunoturbidometrically. The pattern of food consumption, socio-economic, and anthropometric indices were determined; there was no significant change in these indices during the study. RESULTS: There was a significant difference in the blood VitC level at the end of the study in comparison to the initial value in the VitC (p = 0.001) and VitC + n-3FAs (p = 0.027) groups. Similarly, the serum TG level at the end of study was significantly different from the initial value in the n-3FAs group (p = 0.002) and also from the final value in the control group (p = 0.013). In the VitC group, there was a significant decrease in TC (p = 0.004), apo-B (p = 0.005), and MDA (p = 0.015) at the end of study as compared to the respective initial values. There was also a significant increase in blood VitC compared to the control value (p = 0.018) and a significant decrease in MDA compared to the n-3FAs group (p = 0.034). At the end of study, in the n-3FAs group, there was a significant (p = 0.04) and a marginally significant decrease (p = 0.05), respectively, in TG/HDL and apo-B levels as compared to the initial values, and the TG/HDL ratio showed a significant decrease as compared to the control group (p = 0.047). CONCLUSION: Simultaneous administration of n-3FAs and VitC had no beneficial effects on the lipid profile of hyperlipidemic patients, but 1 g purified n-3FAs daily for 10 weeks is a beneficial supplement for decreasing TG without any increase in LDL-C, apo-B or MDA. Administration of 500 mg VitC for more than 10 weeks might decrease significantly TC and apo-B in hyperlipidemic patients. 相似文献
45.
Susan E. Manning Lorna E. Thorpe Chitra Ramaswamy Anjum Hajat Melissa A. Marx Adam M. Karpati Farzad Mostashari Melissa R. Pfeiffer Denis Nash 《Journal of urban health》2007,84(2):212-225
Population-based estimates of human immunodeficiency virus (HIV) prevalence and risk behaviors among men who have sex with
men (MSM) are valuable for HIV prevention planning but not widely available, especially at the local level. We combined two
population-based data sources to estimate prevalence of diagnosed HIV infection, HIV-associated risk-behaviors, and HIV testing
patterns among sexually active MSM in New York City (NYC). HIV/AIDS surveillance data were used to determine the number of
living males reporting a history of sex with men who had been diagnosed in NYC with HIV infection through 2002 (23% of HIV-infected
males did not have HIV transmission risk information available). Sexual behavior data from a cross-sectional telephone survey
were used to estimate the number of sexually active MSM in NYC in 2002. Prevalence of diagnosed HIV infection was estimated
using the ratio of HIV-infected MSM to sexually active MSM. The estimated base prevalence of diagnosed HIV infection was 8.4%
overall (95% confidence interval [CI] = 7.5–9.6). Diagnosed HIV prevalence was highest among MSM who were non-Hispanic black
(12.6%, 95% CI = 9.8–17.6), aged 35–44 (12.6%, 95% CI = 10.4–15.9), or 45–54 years (13.1%, 95% CI = 10.2–18.3), and residents
of Manhattan (17.7%, 95% CI = 14.5–22.8). Overall, 37% (95% CI = 32–43%) of MSM reported using a condom at last sex, and 34%
(95% CI = 28–39%) reported being tested for HIV in the past year. Estimates derived through sensitivity analyses (assigning
a range of HIV-infected males with no reported risk information as MSM) yielded higher diagnosed HIV prevalence estimates
(11.0–13.2%). Accounting for additional undiagnosed HIV-infected MSM yielded even higher prevalence estimates. The high prevalence
of diagnosed HIV among sexually active MSM in NYC is likely due to a combination of high incidence over the course of the
epidemic and prolonged survival in the era of highly active antiretroviral therapy. Despite high HIV prevalence in this population,
condom use and HIV testing are low. Combining complementary population-based data sources can provide critical HIV-related
information to guide prevention efforts. Individual counseling and education interventions should focus on increasing condom
use and encouraging safer sex practices among all sexually active MSM, particularly those groups with low levels of condom
use and multiple sex partners
At the time this work was conducted, Manning and Marx were with the Epidemic Intelligence Service, Office of Workforce and
Career Development, Centers for Disease Control and Prevention, Atlanta, GA, USA; Thorpe, Ramaswamy, Hajat, Marx, Karpati,
Mostashari, and Pfeiffer are with the New York City Department of Health and Mental Hygiene, New York, NY, USA; Nash is with
the Department of Epidemiology and International Center for AIDS Care and Treatment Programs, Columbia Mailman School of Public
Health, New York, NY, USA; Manning is with the Massachusetts Department of Public Health, Bureau of Family and Community Health,
Boston, MA, USA. 相似文献
46.
Today, health systems around the world are under pressure to create greater value for patients and society; increasing access, improving client orientation and responsiveness, reducing medical errors and safety, restraining utilization via managed care, and implementing priority allocation of resources for high-burden health problems are examples of strategies towards this end. The quality paradigm by virtue of its strategic consumer focus and its methods for achieving operational excellence has proved an effective approach for creating higher value in many sectors. If applied in a deliberate and holistic manner, the quality paradigm can bring about a more cost-effective organization of the health systems. In this article, we apply quality concepts to healthcare in a conceptual format; we characterize the health system's customers and outputs with their quality dimensions. The product of this effort is a blueprint for a customer-driven health system which identifies six types of customers, nine types of outputs and the associated operations. As a preliminary step, a new analysis and definition of health and disease is provided. Rethinking the structure of health system in this manner and the related conceptual model can guide medical research, health sciences education, and health services policy, and help the practitioner to integrate all modern trends in healthcare delivery. 相似文献
47.
Rahimzadeh-Rofouyi B Afsharimani B Moezi L Ebrahimi F Mehr SE Mombeini T Ghahremani MH Dehpour AR 《Journal of cardiovascular pharmacology》2007,50(6):641-646
The mechanism of lithium action, an effective treatment for bipolar disease, is still unknown. The present study examined the role of nitric oxide (NO) and prostaglandin systems in lithium modulation of acetylcholine in mesenteric vascular bed of rats by cannulating superior mesenteric artery. Acetylcholine (ACh) or sodium nitroprusside was injected under constant controlled flow induced by phenylephrine; therefore, changes in perfusion pressure reflect changes in resistance. Although 0.5 mM or 1 mM lithium-pretreatment of vascular bed causes reduction in ACh-response, 1.5 mM lithium induced no changes and 2 and 2.5 mM lithium potentiated ACh-induced mesenteric vascular bed relaxation compared to control group. Pretreatment of vascular bed with L-NAME or indomethacin decreased ACh-induced relaxation in 2 concentrations of 0.5 and 2 mM of lithium. The vasorelaxation response to sodium nitroprusside, the NO donor, was not different among lithium groups (0.5 and 2 mM) and controls. In conclusion, there is a dual modulation of endothelium-dependent relaxation, including an inhibitory effect at lower dose and a stimulating effect at higher dose of lithium in rat mesenteric vascular bed. NO synthesis or cyclooxygenase inhibition decreased vasorelaxation in both lower and higher doses of lithium, suggesting a role for NO and prostaglandin in this effect. 相似文献
48.
Zahra Aryan Negar Mahmoudi Ali Sheidaei Shahabeddin Rezaei Zohreh Mahmoudi Kimyia Gohari Nazila Rezaei Mohammad Javad Hajipour Arezou Dilmaghani-Marand Farideh Razi Mahdi Sabooni Farzad Kompani Alireza Delavari Bagher Larijani Farshad Farzadfar 《Journal of clinical lipidology》2018,12(6):1471-1481.e4
49.
A decision tree-based approach for determining low bone mineral density in inflammatory bowel disease using WEKA software 总被引:2,自引:0,他引:2
Firouzi F Rashidi M Hashemi S Kangavari M Bahari A Daryani NE Emam MM Naderi N Shalmani HM Farnood A Zali M 《European journal of gastroenterology & hepatology》2007,19(12):1075-1081
BACKGROUND: Decision tree classification is a standard machine learning technique that has been used for a wide range of applications. Patients with inflammatory bowel disease (IBD) are at increased risk of developing low bone mineral density (BMD). This study aimed at developing a new approach to select truly affected IBD patients who are indicated for densitometry, hence, subjecting fewer patients for bone densitometry and reducing expenses. MATERIALS AND METHODS: Simple decision trees have been developed by means of WEKA (Waikato Environment for Knowledge Analysis) package of machine learning algorithms to predict factors influencing the bone density among IBD patients. The BMD status was the outcome variable whereas age, sex, duration of disease, smoking status, corticosteroid use, oral contraceptive use, calcium or vitamin D supplementation, menstruation, milk abstinence, BMI, and levels of calcium, phosphorous, alkaline phosphatase, and 25-OH vitamin D were all attributes. RESULTS: Testing showed the decision trees to have sensitivities of 65.7-82.8%, specificities of 95.2-96.3%, accuracies of 86.2-89.8%, and Matthews correlation coefficients of 0.68-0.79. Smoking status was the most significant node (root) for ulcerative colitis and IBD-associated trees whereas calcium status was the root of Crohn's disease patients' decision tree. CONCLUSION: BD specialists could use such decision trees to reduce substantially the number of patients referred for bone densitometry and potentially save resources. 相似文献
50.
Mehdi Ghasemi Laleh Montaser-Kouhsari Hamed Shafaroodi Behtash Ghazi Nezami Farzad Ebrahimi Ahmad Reza Dehpour 《Psychopharmacology》2009,206(2):325-333