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排序方式: 共有3593条查询结果,搜索用时 15 毫秒
31.
M A Kenawy J C Beier C M Asiago S E el Said C R Roberts 《Journal of medical entomology》1990,27(4):681-685
Plasmodium infection rates determined by enzyme-linked immunosorbent assay (ELISA) were compared for Anopheles sergentii (Theobald) and An. multicolor Cambouliu in Siwa Oasis, Egypt, an area with low-level Plasmodium vivax transmission, and in Bahariya and Farafra, two other Egyptian oases which appear to be free of malaria. Initial testing indicated that 4.4% (23 of 518) and 0.8% (4 of 518) of the An. sergentii were positive for P. vivax and P. falciparum, respectively, and that 1.4% (1 of 71) of the An. multicolor were positive for P. falciparum. However, after two confirmational tests, only 1.2% (6 of 518) of the An. sergentii remained consistently positive for P. vivax. Initial ELISA absorbance was not a useful predictor of potential false positive reactions in the P. vivax assay. Paradoxically, the six ELISA-positive An. sergentii were from the two malaria-free oases. This study raises the question of whether ELISA-positive reactions for anopheline vector species provides unequivocal evidence for transmission in areas of low malaria endemicity. 相似文献
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33.
Matthew R. Schill Matthew T. Douds Emily L. Burns Michael A. Lahart Ahmed S. Said Aaron M. Abarbanell 《Artificial organs》2021,45(1):15-21
There is a paucity of data regarding the use of direct thrombin inhibitors such as bivalirudin for children on extracorporeal life support (ECLS). We sought to compare the outcomes of children on ECLS anticoagulated with bivalirudin versus heparin. Patients transitioned from heparin to bivalirudin were treated as a separate group. A single‐institution, retrospective review of all consecutive children (neonate to 18 years) placed on ECLS in the cardiac or pediatric intensive care units was performed (June 2018‐December 2019). Data collected included demographics, anticoagulation strategy, number of circuit interventions, blood product use on ECLS, survival to decannulation, and survival to discharge. Fifty‐four children were placed on ECLS for a total of 56 runs. Demographics and venovenous versus venoarterial ECLS were similar. The bivalirudin group had longer median duration of support compared to the heparin group––11.0 days [IQR 6.2, 23.1] versus 3.3 days [2.1, 6.2], P < .001. Patients switched from heparin to bivalirudin had a similar duration of support (10.3 days [8.3, 18.3]) as those on bilvalirudin alone. However, there was no difference in red blood cell, fresh frozen plasma, or platelet transfusions. There was no difference in the number of circuit interventions, survival to decannulation or discharge. The freedom to first circuit intervention was longer with bivalirudin compared to heparin. Our data suggest that even with longer pediatric ECLS runs on bivalirudin, there were no differences in the outcomes between the heparin and bivalirudin groups, with longer freedom from first circuit intervention with bivalirudin. While this is the largest reported series comparing children on ECLS anticoagulated with heparin versus bivalirudin, larger studies are needed to determine the optimal anticoagulation strategy for this diverse and complicated group of children. 相似文献
34.
Brittany N. Burton Devon Carter David J. Dalstrom Engy T. Said Rodney A. Gabriel 《The Journal of foot and ankle surgery》2021,60(4):738-741
We examined the association of body mass index (BMI) with sociodemographic data, medical comorbidities and hospital admission following ambulatory foot and ankle surgery. We conducted an analysis utilizing data from the American College of Surgeons National Surgical Quality Improvement Program database from 2007 to 2016. Adult patients who underwent ankle surgery defined as ankle arthrodesis, ankle open reduction and internal fixation, and Achilles tendon repair in the outpatient setting. We examined 6 BMI ranges: <20 kg/m2 underweight, ≥20 to <25 kg/m2 normal weight, ≥25 to <30 kg/m2 overweight, ≥30 to <40 kg/m2 obese, ≥40 kg/m2to <50 kg/m2 severely obese, and ≥50 kg/m2 extremely obese. The primary outcome was hospital admission. We performed multivariable logistic regression and reported odds ratios (OR) and their associated 95% confidence interval (CI) and considered a p value of <.05 as statistically significant. Data extraction yielded 13,454 adult patients who underwent ambulatory ankle surgery. We then performed listwise deletion to exclude cases with missing observations. After excluding 5.4% of the data, the final study population included 12,729 patients. The overall rate of hospital admission was in the population was 18.6% (2,377/12,729). The overall rate of postoperative complications was 0.03% (4/12,729). We found no significant association of BMI with hospital admission following multivariable logistic regression. We recommend that BMI alone should not be solely used to exclude patients from having ankle surgery performed in an outpatient setting, especially since this patient group makes up a significant proportion of orthopedic surgery. 相似文献
35.
端粒酶活性在人乳癌中的表达 总被引:2,自引:0,他引:2
目的:比较端粒酶活性在乳腺良,恶性病变中的异同,探讨其在乳癌诊断中的意义和与普遍认定的预后指标间的关系。方法:用端凿重复扩增(TRAP)检测了54例乳腺癌、44例乳腺良性病变组织的端粒酶活性。结果:54例乳癌中49例(90.74%)显示端粒酶活性,1例纤维腺瘤有弱端粒酶活性。端粒酶活性与肿瘤大小及分期有关,而与腋淋巴结转移及雌,孕激素受体之间无关。结论:端粒酶活性见于绝大多数浸润性乳癌及极少数纤维 相似文献
36.
The induction of apoptosis by anticancer drugs and its relationship to stages of the cell cycle was studied in cells derived from a solid tumour; a highly malignant hamster fibrosarcoma (Met B). Asynchronously proliferating cells were treated with a wide variety of agents such as actinomycin-D, 1--D-arabinofuranosyl cytosine, camptothecin, cisplatin, cyclophosphamide, daunorubicin, 5-flurouracil, 6-mercaptopurine, hydroxyurea, ionomycin, methotrexate and vincristine. With the exception of cyclophosphamide and hydroxyurea, a 36 h exposure to these drugs resulted in inhibition of cell growth and apart from cyclophosphamide, hydroxyurea, 6-mercaptopurine and cisplatin the induction of apoptosis. Studies using a decreased concentration of drug and exp osure time (12 h) followed by examination of cells using flow cytometry indicated that most drugs were capable of affecting cell cycle progression without induction of apoptosis. However when cells were synchronised at G0/G1, S and G2/M phases and then exposed to these decreased concentrations of drug apart from 6MP an HU, apoptosis was observed and for the majority of drugs it took place in the same phase in which progression through the cell cycle was blocked by the drug. Cells synchronised in G0/G1 phase were more susceptible to methotrexate, whereas S-phase cells were more susceptible to camptothecin and 5-flurouracil and G2/M phase cells more susceptible to actinomycin D, 1--D-arabinofuranosyl cytosine, daunorubicin and cisplatin. In contrast, vincristine blocked cells in G2/M phase but exerted its apoptotic effect in S-phase cells, ionomycin had no effect on the cell cycle, but G2/M cells appeared to be more susceptible to the effect of this drug. These data indicate that entry into apoptosis by this fibrosarcoma may occur at any point in the cell cycle. They also demonstrate a correlation between the action of some anticancer drugs on the cell cycle and the subsequent induction of apoptosis which may be useful in chemotherapeutic design. 相似文献
37.
M. Gawenda S. Said 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1994,379(3):145-151
Zusammenfassung Laparoskopische Operationsmethoden gewannen in den vergangenen Jahren zunehmende Popularität in der Chirurgie. Die laparoskopische Cholezystektomie gilt inzwischen als etabliert. Im Gegensatz dazu ist die laparoskopische Appendektomie weiterhin umstritten. Mittels der computergestützten Literaturdatenbank Medline wurden sämtliche Veröffentlichungen bis zum 31.12.1993 zum Stichwort laparoskopische Appendektomie zusammengetragen. Von 90 Publikationen stellen lediglich 14 einen Vergleich zwischen konventioneller und laparoskopischer Appendektomie an. Lediglich zwei prospektiv randomiserte Studien wurden publiziert. Die geringen Kollektivgrößen lassen eine abschließende Bewertung der laparoskopischen Methode noch nicht zu.
Laparoscopic appendectomy — a review
Laparoscopic methods are becoming increasingly popular in surgery. In the course of a review concerning laparoscopic appendectomy undertaken up to 31 December 1993 all publications were evaluated by computer-assisted recherche. Out of a total of 90 publications only 14 deal with the comparison of the laparoscopic versus open appendectomy. Two prospective randomized studies are published. Because of the low number of patients the evaluation of the laparoscopic method is not yet definite.相似文献
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39.
Said G 《Current opinion in neurology》1999,12(5):627-629
The pathogenesis of primary vasculitides, which are assumed to have an autoimmune pathogenesis, is not well understood. The endothelial cell adhesion molecules seem to play an active role, which varies according to the histopathologic stage of vascular lesions. The role of genetic factors also seems quite important, at least in an experimental model. The reliability of antineutrophil cytoplasmic antibodies testing in diagnosis and follow-up of patients with vasculitis is reviewed. The conclusion is that antineutrophil cytoplasmic antibodies status can be a very useful diagnostic adjunct to the evaluation of patients with suspected Wegener's granulomatosis, but is not a substitute for clinical expertise and histopathologic data during the course of providing patient care. The neurological manifestations of Churg-Strauss syndrome (a variant of polyarteritis nodosa) are very similar to those that occur in polyarteritis nodosa. A role for vasculitis has been confirmed in proximal diabetic neuropathy, which may pave the way for new therapeutic developments. 相似文献
40.