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排序方式: 共有3368条查询结果,搜索用时 15 毫秒
31.
Ortal Harush Nathalie Asherie Shlomit Kfir-Erenfeld Galit Adler Tilda Barliya Miri Assayag Moshe E. Gatt Polina Stepensky Cyrille J. Cohen 《Haematologica》2022,107(10):2395
Chimeric antigen receptor (CAR) T-cell based immunotherapy has become a promising treatment mainly for hematological malignancies. Following the major success of CD19-targeted CAR, new potential targets for other malignancies are required. As such, B-cell maturation antigen (BCMA) is an attractive tumor-associated antigen to be targeted in multiple myeloma (MM). Herein, we aimed at assessing the function and optimal configuration of different BCMA-specific CAR, based on the same targeting moiety but with a different hinge and co-stimulatory domain. We compared their function to that of a previously characterized BCMA-CAR used in clinical trials. All constructs were expressed at high levels by primary human T cells and could trigger cytokine production and cytotoxicity upon co-culture with multiple myeloma targets. Nonetheless, critical differences were observed in off-target activation, exhaustion, and activation marker expression and in vivo anti-tumoral activity mediated by these different constructs. Interestingly, we noted that CD8-based hinge, combined with a 4-1BB intracellular domain, proved superior compared to IgG4-connecting regions, and/or a CD28-signaling moiety respectively. Overall, this study emphasizes the influence of CAR primary structure on its function and led to the identification of a highly efficient BCMA-specific CAR, namely H8BB, which displayed superior anti-tumoral activity both in vitro and long-term in vivo efficacy. 相似文献
32.
Ben-Haroush A Yogev Y Hod M Bar J 《European journal of obstetrics, gynecology, and reproductive biology》2007,130(2):187-192
OBJECTIVES: To evaluate the accuracy of ultrasound-based fetal weight estimates made at 28-34 weeks of gestation in predicting small- and large-for-gestational-age infants (SGA, LGA) at term. METHODS: Two-hundred and fifty-nine patients with a healthy, singleton pregnancy in whom fetal biometry measurements were routinely performed between 28 and 34 weeks' gestation, were recruited at term delivery. The sonographic estimated fetal weight (EFW) and the birth weight were converted to percentiles on the basis of locally developed growth charts and compared. Multivariate linear stepwise regression analysis was used to predict the birth weight and birth weight percentile. The resulting equation (projectile formula) was used to determine the calculated birth weight, and that value was compared with the actual birth weight. The Bland and Altman plot and Passing and Bablok regression were used to compare between the calculated birth weight and the actual birth weight. RESULTS: Mean gestational age at ultrasound examination was 32+/-1.6 weeks (28-34), and mean age at delivery was 39+/-1.7 weeks (37-42). The multivariate correlation between the calculated birth weight and the birth weight (R2 = 0.524) was higher than the correlation between the sonographic EFW and the birth weight (R2 = 0.083). Both the sonographic EFW and the calculated birth weight are characterized by low positive predictive values in predicting SGA or LGA infants. The calculated birth weight was more accurate in excluding SGA and LGA infants (negative predictive values of 99.5% and 100%, respectively). On method comparison tests, the calculated birth weight was not significantly different than the actual birth weight. CONCLUSIONS: Fetal weight estimation at the early third trimester poorly predicts the birth weight centile at term. It remains uncertain, however, if it would be useful to use the calculated birth weight in pregnancies with clinically suspected SGA or LGA fetuses. 相似文献
33.
Levy A Sheiner E Hammel RD Hershkovitz R Hallak M Katz M Mazor M 《Archives of gynecology and obstetrics》2006,273(4):203-206
Background: The study was aimed to compare pregnancies complicated with shoulder dystocia, of patients with and without diabetes mellitus.
Methods: A comparison of all singleton, vertex, term deliveries between the years 1988–1999, complicated with shoulder dystocia with
and without diabetes mellitus was performed. Statistical analysis was done using receiver operating characteristic curve analysis.
Results: Using a receiver operating characteristic curve analysis, the area under the curve for birth weight was 0.92 (95% CI 0.90–0.93).
However, for birth weight of 4,000 g the sensitivity was only 56% with specificity of 95%. While comparing shoulder dystocia
between patients with (n=38) and without diabetes mellitus (n=207), neonates of the diabetic patients were significantly heavier (mean birth weight 4,244.2±515.1 vs. 4,051.6±389.5; P=0.008) and had higher rate of Apgar scores lower than 7 at 1 min (50.0% vs. 25.9%; P=0.030), but not at 5 min (2.6% vs. 2.0%; P=0.083) when compared to the non-diabetic group. No significant differences were noted regarding perinatal mortality between
the groups (0% vs. 4.3%; P=0.362). Conclusions: The newborn of the diabetic mother complicated with shoulder dystocia does not appear to be at an increased risk for perinatal
morbidity compared with the newborn of the non-diabetic mother.
Presented in part at the Society for Gynecologic Investigation 50th Annual Scientific Meeting, Washington, DC, 27–30 March
2003. 相似文献
34.
Orna Geyer Anat Loewenstein Bruria Shalmon Meira Neudorfer Moshe Lazar 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1995,233(7):448-451
Background: Since dapiprazole on alpha-adrenergic agent, produces miosis by paralyzing the dilator muscle, and pilocarpine, a parasympathetic drug, causes miosis by affecting the sphincter, we speculated that the two drugs might have additive effects. Methods: The additive miotic actions of pilocarpine 2% and dapiprazole 0.5% were evaluated by comparing the effects of two drugs given together and alone on the reversal of mydriasis induced by tropicamide (0.5%) and phenylephrine (10%) in one eye each of 60 healthy volunteers. Results: Dapiprazole and pilocarpine together induced miosis significantly faster than each drug alone, showing additive effects. Conclusion: Co-administration of dapiprazole and pilocarpine at the end of the eye examination will induce fast pupillary constriction, which might be useful in preventing the development of an acute attack of angle-closure glaucoma in patients with anatomically narrow angles. 相似文献
35.
36.
Gilad Feinmesser Raphael Feinmesser Eran Alon Moshe Leshno 《American journal of otolaryngology》2021,42(3):102868
PurposeThe value of parotidectomy in older patients is unclear. This study presents a decision model to help resolve this question.Materials & methodsA Markov model with Monte Carlo simulation was used to compare outcomes in patients of different ages with pleomorphic adenoma of the parotid gland treated by surgery or surveillance.ResultsIn 30-year-old patients, surgery conferred a 3.5-year gain in life expectancy whereas in 75-year-olds, it was only 0.74 months. The expected rate of malignant transformation at age 30 years was 6.5% after surgery and 26.5% after surveillance; at age 65, corresponding rates were 0.8% and 10.7%. Sensitivity analysis showed that age was the only parameter that significantly contributed to life expectancy. The benefit of surgery was restricted in older patients.ConclusionOur Markov decision-analysis model suggests that patients older than 65 years with pleomorphic adenoma have a limited survival advantage with surgery compared to surveillance. 相似文献
37.
38.
Levy D Jakubowski M Burstein R 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(12):4274-4279
Triptans are 5HT(1B/1D) receptor agonists commonly prescribed for migraine headache. Although originally designed to constrict dilated intracranial blood vessels, the mechanism and site of action by which triptans abort the migraine pain remain unknown. We showed recently that sensitization of peripheral and central trigeminovascular neurons plays an important role in the pathophysiology of migraine pain. Here we examined whether the drug sumatriptan can prevent and/or suppress peripheral and central sensitization by using single-unit recording in our animal model of intracranial pain. We found that sumatriptan effectively prevented the induction of sensitization (i.e., increased spontaneous firing; increased neuronal sensitivity to intracranial mechanical stimuli) in central trigeminovascular neurons (recorded in the dorsal horn), but not in peripheral trigeminovascular neurons (recorded in the trigeminal ganglion). After sensitization was established in both types of neuron, sumatriptan effectively normalized intracranial mechanical sensitivity of central neurons, but failed to reverse such hypersensitivity in peripheral neurons. In both the peripheral and central neurons, the drug failed to attenuate the increased spontaneous activity established during sensitization. These results suggest that neither peripheral nor central trigeminovascular neurons are directly inhibited by sumatriptan. Rather, triptan action appears to be exerted through presynaptic 5HT(1B/1D) receptors in the dorsal horn to block synaptic transmission between axon terminals of the peripheral trigeminovascular neurons and cell bodies of their central counterparts. We therefore suggest that the analgesic action of triptan can be attained specifically in the absence, but not in the presence, of central sensitization. 相似文献
39.
Mittelman M Zeidman A Kanter P Katz O Oster H Rund D Neumann D 《European journal of haematology》2004,72(3):155-165
Recombinant human erythropoietin (rHuEpo) was introduced into clinical practice more than a decade ago, and has been found to be effective in the treatment of several types of anemia, including anemia of end-stage renal failure and cancer-related anemia. No study has suggested that Epo might have an effect on the biology of the disease, nor any survival advantage to cancer patients treated with Epo for anemia has been reported. Here we report six patients with advanced multiple myeloma (MM) with very poor prognostic features, whose expected survival was <6 months. All six patients were treated with rHuEpo for their anemia, either without any chemotherapy or very mild chemotherapy for a short time. Yet, surprisingly they lived for 45-133 months totally from MM diagnosis and 38-94 months with rHuEpo (with a good quality of life). In fact, one patient, is still alive and well, more than 8 yr after chemotherapy was discontinued because of a resistant aggressive disease. The course in these six MM patients led us to hypothesize that Epo might have an antineoplastic or antimyeloma effect. We proceeded and tested that hypothesis in mouse models of myeloma (Mittelman M et al., Proc Natl Acad Sci USA 98:5181,2001). In these models we confirmed that rHuEpo induced tumor regression in about 50% of the BALB/c mice inoculated with MOPC-315 myeloma cells. We then presented evidence that the mechanism is a new immune-mediated phenomenon, via activation of CD8+ T cells. Furthermore, evidence from the literature supports the antineoplastic effect of Epo. Epo might be used as an adjunct immune treatment in various malignant diseases, in addition to the current regimens and chemotherapeutic protocols. Future trials should determine the role of Epo in myeloma and cancer treatment, besides clarifying concerns about the presence of Epo receptors on some tumor cells. 相似文献
40.
We report a case of acromegaly with relatively low GH secretion in a patient with GH-secreting pituitary macroadenoma. The 44-year-old male patient presented with left temporal hemianopsia and characteristic acromegalic face, but had relatively low baseline and post-glucose GH levels. IGF-1 and IGFBP-1 were elevated. Transsphenoidal surgery did not achieve clinical or biochemiacl remission, and the patient still had elevated IGF-1 levels with low GH. Histological examination of the resected tumor revealed a pituitary adenoma stained weakly for GH. The patient was treated then with monthly injections of Sandostatin-LAR, with clinical improvement and suppression of IGF-I to the normal range. This is a rare case of acromegaly without elevated GH levels, and good response to treatment with somatostatin analog, as expected in classical GH-secreting pituitary adenomas. 相似文献