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71.
Correlation between radionuclides uptake and ultrastructural features of tight junctions in the capillary wall of meningiomas. 下载免费PDF全文
P Bar-Sella D Front E Peyser A Talmon O Israel I Nir 《Journal of neurology, neurosurgery, and psychiatry》1981,44(11):1024-1028
The uptake of Tc-99m pertechnetate and Co-57 bleomycin and the ultrastructure of small blood vessels were studied in 10 cases of meningioma. When thin sections of 120 contact areas between adjacent endothelial cells were examined, 92% of the intercellular contacts contained one to three punctate tight junctions. Freeze fracture preparations revealed fascia occludens with one to four sealing strands. These findings are consistent with the high permeability the meningiomas displayed for both of the radiopharmaceuticals. 相似文献
72.
A prospective trial of magnetic resonance–guided focused ultrasound thalamotomy for essential tremor: Results at the 2‐year follow‐up 下载免费PDF全文
Jin Woo Chang MD PhD Nir Lipsman MD PhD Michael L. Schwartz MD Pejman Ghanouni MD PhD Jaimie M. Henderson MD Ryder Gwinn MD Jennifer Witt MD Travis S. Tierney MD PhD G. Rees Cosgrove MD Binit B. Shah MD Keiichi Abe MD Takaomi Taira MD PhD Andres M. Lozano MD Howard M. Eisenberg MD Paul S. Fishman MD PhD W. Jeffrey Elias MD 《Annals of neurology》2018,83(1):107-114
73.
Application of the Movement Disorder Society prodromal criteria in healthy G2019S‐LRRK2 carriers 下载免费PDF全文
Anat Mirelman PhD Rachel Saunders‐Pullman MD MS MPH Roy N. Alcalay MD MSc Shiran Shustak BSc Avner Thaler MD PhD Tanya Gurevich MD Deborah Raymond MS Helen Mejia‐Santana MS Martha Orbe Reilly MD Laurie Ozelius PhD Lorraine Clark PhD Mali Gana‐Weisz PhD Anat Bar‐Shira PhD Avi Orr‐Utreger MD PhD Susan B. Bressman MD Karen Marder MD MPH Nir Giladi MD the AJ LRRK Consortium 《Movement disorders》2018,33(6):966-973
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75.
J B Zeldis H Mugishima H N Steinberg E Nir R P Gale 《The Journal of clinical investigation》1986,78(2):411-417
Infection of humans with hepatitis B virus (HBV) frequently results in suppression of hematopoiesis; in some cases this may lead to severe bone marrow failure. The mechanism whereby HBV infection affects hematopoiesis is unknown. In vitro exposure of human bone marrow to HBV results in a dose-dependent inhibition of erythroid (erythroid burst forming units, BFU-E; erythroid colony-forming units CFU-E), myeloid (colony-forming units-granulocyte macrophage CFU-GM), and lymphoid (CFU-[T-lymphocytic]-TL) hematopoietic stem cells. Inactivation or immunoabsorption of HBV from sera resulted in loss of HBV-induced inhibition of hematopoietic stem cells. De novo gamma interferon was not detectable in the supernatants of cultures of bone marrow cells with HBV. Antibodies to gamma interferon did not affect the suppression of hematopoietic stem cells by HBV. Hepatitis B surface antigen (HBsAg) was detected by immune electron microscopy in nuclei of greater than 70% of immature hematopoietic cells including myeloblasts, normoblasts, and lymphoblasts; granulocytes had mostly cytoplasmic HBsAg. Hepatitis B virus core antigen (HBcAg) was also detected in about 5% of HBV infected bone marrow cells by immunoperoxidase staining. These data indicate that HBV can infect hematopoietic cells and their progenitors, thus suggesting a wider range of tropism for HBV than previously reported. These results may provide a basis to study HBV infection in vitro, and the effects of HBV on hematopoiesis. 相似文献
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Yftach Gepner Nir Goldstein Ilan Shelef Dan Schwarzfuchs Hila Zelicha Anat Yaskolka Meir Gal Tsaban Ehud Grossman 《Journal of general internal medicine》2021,36(8):2300
BackgroundObesity is associated with elevated blood pressure (BP). In patients with obesity and hypertension, weight loss lowers BP, but the long-term effect of weight loss on BP is less clear.ObjectiveWe aimed to assess the effect of long-term weight loss intervention on BP in normotensive and hypertensive subjects.DesignRandomized controlled trial.ParticipantsTwo hundred seventy-eight subjects (mean age 47.9 ± 9.3 years, 89% male, 56% hypertensive) with abdominal obesity or elevated serum triglycerides and low high-density lipoprotein cholesterol were recruited.InterventionEighteen-month weight loss intervention.Main MeasuresBody weight and BP were measured at baseline, after 6 and 18 months.ResultsAfter 6 months of intervention, in the weight loss phase, body mass index (BMI) decreased by an average of −2.2±1.5 kg/m2 (p<0.001) and both diastolic BP (DBP) and systolic BP (SBP) decreased by −2.1±8.8 mmHg and −2.3±12.9 mmHg, respectively (p<0.01 for both). The change in BMI was similar in normotensive and hypertensive subjects (−2.0±1.6 and −2.3±1.5, p = 0.246). However, DBP and SBP decreased significantly (−5.2±7.1 mmHg and −6.2±12.5 mmHg, respectively, p<0.001 for both) in hypertensive subjects, and increased in normotensive subjects (1.8±9.3 mmHg, p = 0.041 and 2.7±11.7 mmHg, p = 0.017, respectively). After 18 months, in the weight maintenance phase, BMI slightly increased (0.9±1.3 kg/m2, p<0.001) but remained significantly lower than at baseline (p<0.0001). Unlike BMI, DBP and SBP increased significantly in hypertensive subjects (p<0.001) and returned almost to baseline levels.ConclusionWeight-loss intervention reduced BP in hypertensive patients, but this was not maintained in the long run.Clinical Trial RegistrationClinicalTrials.gov Identifier: KEY WORDS: NCT01530724blood pressure, weight loss, body mass index, hypertension, randomized controlled trial 相似文献
78.
Pierantonio Laveneziana Piergiuseppe Agostoni Andrea Mignatti Saima Mushtaq Paolo Colombo Daniel Sims Nir Uriel Ulrich P. Jorde 《Journal of cardiac failure》2010,16(7):548-555
BackgroundThis is the first study to examine the effect of acute (24-hour) β-blocker withholding on ventilatory efficiency in patients with advanced chronic heart failure (CHF) during maximal incremental treadmill cardiopulmonary exercise test.Methods and ResultsSeventeen CHF patients were studied either 3 hours after administration of β-blocker (BBON) or 27 hours after the last β-blocker ingestion (BBOFF). The ventilatory efficiency was measured via the slope of the linear relationship between ventilation (V′E) and carbon dioxide production (V′CO2) (ie, V′E/V′CO2 slope). Measurements were also made at rest, anaerobic threshold (AT), maximal end-tidal pressure for carbon dioxide (PETCO2max), respiratory compensation point (RC), and peak exercise. Compared with BBON, the V′E/V′CO2 slope was significantly increased during BBOFF (30.8 ± 7.4 vs. 29.1 ± 5.4, P = .04). At peak exercise, oxygen uptake (V′O2, 16.0 ± 2.7 vs. 15.6 ± 2.8 mL·kg·min) and V′CO2 (1458 ± 459 vs. 1414 ± 429 mL/min) were not different between the 2 conditions, whereas V′E was higher during BBOFF (49.5 ± 10.7 vs. 46.1 ± 9.6 L/min, P = .04). No differences were noted at AT and RC in V′O2, V′CO2, V′E, V′E/V′O2, and V′E/V′CO2 ratios during the 2 conditions. At PETCO2max, used to noninvasively estimate the CO2 set point, V′E was higher (33.9 ± 7.6 vs. 31.7 ± 7.3 L/min, P = .002) and PETCO2 was lower (37.4 ± 4.8 vs. 38.5 ± 4.0 mm Hg, P = .03), whereas V′CO2 was unchanged (1079 ± 340 vs. 1050 ± 322 mL/min) during BBOFF.ConclusionAcute β-blocker withholding resulted in decreased ventilatory efficiency mostly from an increase of V′CO2-independent regulation of V′E and less likely from a change in ventilation/perfusion mismatching. 相似文献
79.
Peled N Shitrit D Bendayan D Peled E Kramer MR 《Respiration; international review of thoracic diseases》2007,74(1):50-55
BACKGROUND: Although certain studies report high levels of vascular endothelial growth factor (VEGF) in obstructive sleep apnea syndrome (OSAS), the effect of systemic hypoxia on circulating VEGF remains controversial. OBJECTIVES: To study the association of serum VEGF and OSAS in a large group of patients. METHODS: One hundred patients with OSAS (mean age 58.1+/-12.4 years, mean body mass index 30.6+/-5.4 kg/m2) were tested for serum VEGF levels, and the findings were correlated with the severity of OSAS, as determined by the apnea-hypopnea index (AHI) on the basis of polysomnography and background data. RESULTS: The mean AHI was 40.0+/-21.2 (range 10-106). Mean minimal oxygen saturation was 80.6+/-11.7% (range 43-98%) and mean time of oxygen saturation under 90% was 50.0+/-75.0 min (range 0-300 min). The mean VEGF level was 445.2+/-289.8 pg/ml in the study group (vs. 280 pg/ml reported in normal controls). The mean platelet count was 233.8+/-64.4 10(3)/ml and the mean VEGF/platelet ratio was 1.95+/-1.40 pg/10(6). There was no association of VEGF or VEGF/platelets with the severity of OSAS. However, both factors showed a significant correlation with patient age (r=0.224, p=0.01 and r=0.425, p=0.01, respectively). Age was the only parameter to significantly predict VEGF and VEGF/platelets on multivariate analysis (R2=0.713, p=0.001 and R2=0.844, p=0.001, respectively). CONCLUSION: The elevation of serum VEGF in OSAS is not associated with the severity of the disease, but it is associated with patient age. VEGF might be involved in the long-term adaptive mechanism in OSAS, and its age-dependent increase might partly explain the reduced mortality in elderly OSAS patients. 相似文献
80.
Comparison of positive allergy skin tests among asthmatic children from rural and urban areas living within small geographic area. 总被引:1,自引:0,他引:1
Haim Bibi David Shoseyov David Feigenbaum Pnina Nir Rosa Shiachi Shimon Scharff Ronit Peled 《Annals of allergy, asthma & immunology》2002,88(4):416-420
BACKGROUND: Evidence of increased asthma and allergic response among urban versus rural residents has been reported. OBJECTIVE: To evaluate the prevalence of allergic response among asthmatic children from urban and rural areas living within close proximity. METHODS: In all, 448 asthmatic children from urban (363) and rural (85) areas were studied. The study group consisted of 234 9-year-olds and 214 12-year-olds. A health questionnaire was completed on each child who subsequently underwent allergic skin prick tests (SPTs). RESULTS: There was significantly more positive SPT response to house-dust mite, mold, cat, and cypress among asthmatic children from urban areas compared with children living in rural areas: 58.3% versus 37.6%, 46.1% versus 31.8%, 17.45 versus 5.9%, and 26.2% versus 15.3%, respectively. Positive SPT for indoor allergens were significantly greater among asthmatic urban residents than asthmatic rural residents: 63.3% versus 45.5%, respectively (P < 0.02). Positive SPT response to all the allergens checked was higher among the 12-year-old age group when compared with the 9-year-olds, 34.6% versus 22.7%, respectively (P = 0.05). CONCLUSIONS: Allergic response measured by SPT is significantly more common among asthmatic children from urban areas as opposed to rural, even though both areas are within small distance of one another. Further, asthmatic children living in urban areas demonstrated more allergic response to both indoor and outdoor allergens. The allergic response tends to increase with increased age in both urban and rural asthmatic children. 相似文献