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排序方式: 共有1618条查询结果,搜索用时 15 毫秒
1.
Krishna Pillai Javid Akhter Terence C. Chua Mena Shehata Nayef Alzahrani Issan Al-Alem David L. Morris 《Medicine》2015,94(9)
Thermal ablation of liver tumors near large blood vessels is affected by the cooling effect of blood flow, leading to incomplete ablation. Hence, we conducted a comparative investigation of heat sink effect in monopolar (MP) and bipolar (BP) radiofrequency ablation (RFA), and microwave (MW) ablation devices.With a perfused calf liver, the ablative performances (volume, mass, density, dimensions), with and without heat sink, were measured. Heat sink was present when the ablative tip of the probes were 8.0 mm close to a major hepatic vein and absent when >30 mm away. Temperatures (T1 and T2) on either side of the hepatic vein near the tip of the probes, heating probe temperature (T3), outlet perfusate temperature (T4), and ablation time were monitored.With or without heat sink, BP radiofrequency ablated a larger volume and mass, compared with MP RFA or MW ablation, with latter device producing the highest density of tissue ablated. MW ablation produced an ellipsoidal shape while radiofrequency devices produced spheres.Percentage heat sink effect in Bipolar radiofrequency : Mono-polar radiofrequency : Microwave was (Volume) 33:41:22; (mass) 23:56:34; (density) 9.0:26:18; and (relative elipscity) 5.8:12.9:1.3, indicating that BP and MW devices were less affected.Percentage heat sink effect on time (minutes) to reach maximum temperature (W) = 13.28:9.2:29.8; time at maximum temperature (X) is 87:66:16.66; temperature difference (Y) between the thermal probes (T3) and the temperature (T1 + T2)/2 on either side of the hepatic vessel was 100:87:20; and temperature difference between the (T1 + T2)/2 and temperature of outlet circulating solution (T4), Z was 20.33:30.23:37.5.MW and BP radiofrequencies were less affected by heat sink while MP RFA was the most affected. With a single ablation, BP radiofrequency ablated a larger volume and mass regardless of heat sink. 相似文献
2.
Regression of lymphomatous skin deposits in a chronic lymphocytic leukemia patient treated with the Toll-like receptor-7/8 agonist, imiquimod. 总被引:2,自引:0,他引:2
David E Spaner Richard L Miller Jenny Mena Larry Grossman Vicki Sorrenti Yonghong Shi 《Leukemia & lymphoma》2005,46(6):935-939
The identification of clinically relevant, active immunomodulatory agents is important for developing immunotherapeutic approaches to chronic lymphocytic leukemia (CLL) and other B-cell lymphomas that are not curable with conventional chemotherapy. In this investigation, the imidazoquinoline Toll-like receptor (TLR)-7/8 agonist, imiquimod, was found to mediate the clearance of a lymphomatous skin lesion in a CLL patient. Imidazoquinolines also activated TLR-7/8 signaling pathways, resulting in increased expression of costimulatory molecules on circulating tumor cells. These observations extend the therapeutic spectrum of imiquimod to cutaneous B-cell lymphomas and suggest the use of TLR-7/8 agonists in CLL immunotherapy. 相似文献
3.
J. Randolph Swartz Ira M. Lesser Kyle B. Boone Bruce L. Miller Ismael Mena 《International journal of geriatric psychiatry》1995,10(6):437-446
Global and regional cerebral blood flow (CBF) were evaluated with single photon emission computerized tomography (SPECT) utilizing both 133Xenon (133Xe) (47 subjects, 47–82 years old) and 99Tc-hexamethylpropyleneamine oxime (99Tc-HMPAO) (27 subjects, 47–80 years old). The 133Xe results showed: among total subjects, no age-related decline in global CBF, but a significant regional decline in the occipital lobe (p < 0.05); among men, significant age-related declines in global, frontal, temporal, occipital and right hemisphere CBF (all p < 0.05); among women, no age-related decline in global or regional CBF. The 99Tc-HMPAO results showed no age-related decline in either global or regional perfusion among total subjects, men or women. These results suggest that age-related global and regional (including frontal lobe) CBF declines do not occur in healthy control subjects after the age of 45 years. However, gender differences in age-related CBF changes warrant further study. 相似文献
4.
Antinori Andrea Cingolani Antonella Lorenzini Patrizia Giancola Maria Letizia Uccella Ilaria Bossolasco Simona Grisetti Susanna Moretti Francesca Vigo Beniamino Bongiovanni Marco Del Grosso Bruno Arcidiacono Maria Irene Fibbia Giovanni Carlo Mena Maurizio Finazzi Maria Grazia Guaraldi Giovanni Ammassari Adriana Monforte Antonella dArminio Cinque Paola De Luca Andrea 《Journal of neurovirology》2003,9(1):47-53
Human immunodeficiency virus (HIV)-associated progressive multifocal leukoencephalopathy (PML) remains a relevant clinical problem even in the era of highly active antiretroviral therapy (HAART). Aims of the study were to analyze clinical and treatment-related features and the survival probability of PML patients observed within the Italian Registry Investigative Neuro AIDS (IRINA) during a 29-month period of HAART. Intravenous drug use, the presence of focal signs, and the involvement of white matter at neuroradiology increased the risk of having PML. A reduced probability of PML was observed when meningeal signs were reported. Patients starting HAART at PML diagnosis and previously naïve for antiretrovirals showed significantly higher 1-year probability of survival (.58), compared to those continuing HAART (.24), or never receiving HAART (.00). Higher CD4 cell count were associated with a higher survival probability (.45). At multivariate analysis, a younger age, higher CD4, starting HAART at PML diagnosis, the absence of previous acquired immunodeficiency syndrome (AIDS)-defining events, and the absence of a severe neurologic impairment were all associated with a reduced hazard of death. The use of cidofovir showed a trend towards a reduced risk of death. 相似文献
5.
6.
Adverse outcomes of planned and unplanned pregnancies among users of natural family planning: a prospective study. 总被引:3,自引:1,他引:2 下载免费PDF全文
A Bitto R H Gray J L Simpson J T Queenan R T Kambic A Perez P Mena M Barbato C Li V Jennings 《American journal of public health》1997,87(3):338-343
OBJECTIVES: The purpose of this study was to determine prospectively whether unplanned pregnancies are associated with adverse pregnancy outcomes among users of natural family planning. METHODS: Women who became pregnant while using natural family planning were identified in five centers worldwide: there were 373 unplanned and 367 planned pregnancies in this cohort. The subjects were followed up at 16 and 32 weeks' gestation and after delivery. The risks of spontaneous abortion, low birth-weight, and preterm birth were estimated after adjustment by logistic regression. RESULTS: The women with unplanned pregnancies were more likely to be at the extremes of age, to report more medical problems before and during the index pregnancy, and to seek antenatal care later in gestation than the women with planned pregnancies. However, women with planned pregnancies reported a higher rate of spontaneous abortion in previous pregnancies (28.8%) than did women with unplanned pregnancies (12.9%). There were no significant differences in the rates of spontaneous abortion, low birthweight, or preterm birth between the two groups. CONCLUSIONS: No increased risk of adverse pregnancy outcomes was observed among women who experienced an unplanned pregnancy while using natural family planning. 相似文献
7.
C. Noonan M. Farrell J. Mullaney H. Cassidy M. A. Asghar B. J. Young Marie Hickey-Dwyer A. Patterson W. Power M. Hillery A. Benedict-Smith L. M. T. Collum S. Fitzsimon E. O’Donoghue R. Hitchings G. B. Arden A. O’Mahony A. Murray A. Whyte M. Shehata Hugh O’Donoghue Rosemary Robinson J. Toland P. Eustace 《Irish journal of medical science》1991,160(10):322-324
8.
A Zemtsov D J Yanase A S Boyd B Shehata 《Cutis; cutaneous medicine for the practitioner》1992,50(4):281-282
Fixed drug eruptions due to Tylenol (paracetamol, acetaminophen) are very rare. The authors report two additional cases and review the literature. 相似文献
9.
Review of imaging techniques for the diagnosis of breast cancer: a new role of prone scintimammography using technetium-99m sestamibi 总被引:6,自引:4,他引:2
Iraj Khalkhali Ismael Mena Linda Diggles 《European journal of nuclear medicine and molecular imaging》1994,21(4):357-362
Imaging techniques currently used for the diagnosis of breast cancer are reviewed and compared. Besides mammography, magnetic resonance imaging, positron emission tomography, and thallium-201 scintimammography, a new role of technetium-99m sestamibi scintimammography is discussed. It is concluded that while mammography remains the procedure of choice in screening asymptomatic women for breast cancer, other imaging methods play an important role in detecting malignancies in symptomatic patients.99mTc-sestamibi scintimammography has high sensitivity and improves the specificity of conventional mammography for the detection of breast cancer; with this technique, prone imaging is preferable to supine imaging.99mTc-sestamibi scintimammography thus deserves further study as a screening technique. 相似文献
10.
Leishmania infantum MON-98 isolated from naturally infected Phlebotomus langeroni (Diptera: Psychodidae) in El Agamy, Egypt. 总被引:1,自引:0,他引:1
Leishmania infantum zymodeme MON-98 was isolated in El Agamy, Egypt. A total of 15 (1.07%) Leishmania-like infections in the anterior midgut and in the head was found in 1,405 Phlebotomus langeroni (Nitzulescu); none of 1,785 Phlebotomus papatasi (Scopoli) was found infected. Four of the 15 cultures (26.7%) were indistinguishable from a reference L. infantum MON-98 strain using cellulose acetate electrophoresis. The isolation and identification of L. infantum MON-98 from naturally infected P. langeroni confirms that this species of sand fly is the vector of visceral leishmaniasis in El Agamy. 相似文献