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41.
Frederick Thurston Drake Elina Quiroga Hazel W. Kariuki Kizito A. Shisanya Matthew P. Hotchkiss Aliza Monroe-Wise John K. Drake Joseph Mburu Carey Farquhar David R. Flum 《The Journal of surgical research》2014
A 34-y-old man presented to Naivasha District Hospital (NDH) in Naivasha Town, Kenya, with near-complete below-knee amputation and hemorrhage after a hippopotamus attack. Residents from the University of Washington (UW), Departments of Surgery, Anesthesia, and Medicine, were rotating at NDH with the Clinical Education Partnership Initiative, a joint venture of UW and University of Nairobi. These providers met the patient in the operating theater. The leg was mangled with severely traumatized soft tissues and tibia–fibula fractures. The visiting UW Surgery resident (R3) and an NDH medical officer (second-year house officer) performed emergency below-knee completion amputation—the first time either had performed this operation. The three major vessel groups were identified and ligated. Sufficient gastrocnemius and soleus were preserved for future stump construction. The wound was washed out, packed with betadine-soaked gauze, and wrapped in an elasticized bandage. Broad-spectrum antibiotics were initiated. Unfortunately, the patient suffered infection and was revised above the knee. After a prolonged course, the patient recovered well and was discharged home. NDH house officers and UW trainees collaborated successfully in an emergency and conducted the postoperative care of a patient with a serious and challenging injury. Their experience highlights the importance of preparedness, command of surgical basics, humility, learning from mistakes, the expertise of others, a digitally connected surgical community, and the role of surgery in global health. These lessons will be increasingly pertinent as surgical training programs create opportunities for their residents to work in developing countries; many of these lessons are equally applicable to surgical practice in the developed world. 相似文献
42.
Viviana Cuartas Alberto Aragn-Muriel Yamil Liscano Dorian Polo-Cern Maria del Pilar Crespo-Ortiz Jairo Quiroga Rodrigo Abonia Braulio Insuasty 《RSC advances》2021,11(38):23310
Multidrug resistance to chemotherapy is a critical health problem associated with mutation of the therapeutic target. Therefore, the development of anticancer agents remains a challenge to overcome cancer cell resistance. Herein, a new series of quinazoline-based pyrimidodiazepines 16a–g were synthesized by the cyclocondensation reaction of 2-chloro-4-anilinoquinazoline-chalcones 14a–g with 2,4,5,6-tetraaminopyrimidine. All quinazoline derivatives 14a–g and 16a–g were selected by the U.S. National Cancer Institute (NCI) for testing their anticancer activity against 60 cancer cell lines of different panels of human tumors. Among the tested compounds, quinazoline-chalcone 14g displayed high antiproliferative activity with GI50 values between 0.622–1.81 μM against K-562 (leukemia), RPMI-8226 (leukemia), HCT-116 (colon cancer) LOX IMVI (melanoma), and MCF7 (breast cancer) cancer cell lines. Additionally, the pyrimidodiazepines 16a and 16c exhibited high cytostatic (TGI) and cytotoxic activity (LC50), where 16c showed high cytotoxic activity, which was 10.0-fold higher than the standard anticancer agent adriamycin/doxorubicin against ten cancer cell lines. COMPARE analysis revealed that 16c may possess a mechanism of action through DNA binding that is similar to that of CCNU (lomustine). DNA binding studies indicated that 14g and 16c interact with the calf thymus DNA by intercalation and groove binding, respectively. Compounds 14g, 16c and 16a displayed strong binding affinities to DNA, EGFR and VEGFR-2 receptors. None of the active compounds showed cytotoxicity against human red blood cells.A new series of quinazoline-based chalcones and pyrimidodiazepines were tested against 60 human tumor cell lines. 相似文献
43.
44.
Background
To determine differences among persons who provided blood specimens for HIV testing compared with those who did not among those interviewed for the population-based Zimbabwe Young Adult Survey (YAS). 相似文献45.
The usefulness of the direct 4-hour radioimmunoassay of estriol-16-glucuronide (E3G) and pregnanediol-3-glucuronide (P2G) in first morning urine (FMU) for establishing a prognosis of the early pregnancy outcome was evaluated in 106 patients that became pregnant. Microaliquots of FMU were serially assayed from day 3 of the conception cycle until day 80 of pregnancy. The E3G and P2G profiles of 19 pregnancies which terminated in spontaneous abortion with either a diagnosis of the blighted ovum syndrome (n = 11) or presumption of a corpus luteum/trophoblast failure (n = 8) have been compared with those of clinically normal pregnancies (n = 87). Normal pregnancies displayed typical patterns of E3G and P2G development, while variations were observed in abortive events that reflected changes of the fetoplacental unit. 相似文献
46.
A B Merlo Z Farinati S Quiroga C A Nagle L M Carril M Lahoz A F Mendizabal 《International journal of fertility》1984,29(3):189-193
The concentrations of estrone-3-glucuronide (E(1)3G) and pregnanediol-3-glucuronide (P(2)3G) in daily samples of early morning urine (EMU) were correlated with the levels of estradiol (E2), progesterone (P) and LH in respective plasma samples. Forty-six menstrual cycles were studied, in order to determine the practical usefulness of the urine assays for detecting: a) an individualized estrogen concentration threshold value, announcing the approach of ovulation. b) an individualized signal provided by P(2)3G in urine from which it can be assumed that ovulation has already occurred. The results showed that the concentration of E2 in plasma, in any day of the cycle, can be precisely inferred from the respective concentration of E(1)3G in EMU. The estimation of the plasmatic P values from those of P(2)3G in EMU had to be based on different factors according to the phase of the cycle, fact that suggests the presence of a phase-related variation in the glucuronization of P metabolites. Considering three consecutive E(1)3G urinary assay results, it was possible to identify a threshold value termed Estrogen-Peak Initiating Rise (E-PIR), which anticipated in 3.02 +/- 0.18 days the occurrence of an LH peak. The attempts to detect the occurrence of ovulation by an individualized urinary P(2)3G signal proved disappointing. The signal was detected, either before, simultaneously or after the LH peak. 相似文献
47.
We measured total respiratory system compliance (Crs) before and after instilling 25 mg artificial surfactant in 1 ml saline down the endotracheal tube of preterm babies requiring resuscitation at birth, and compared results with data from 6 similar babies receiving saline only. Surfactant did not produce a significant improvement in Crs. 相似文献
48.
49.
Sparks DL Connor DJ Browne P Sabbagh MN;AD Cholesterol-Lowering Treatment Trial Team 《Journal of molecular neuroscience : MN》2002,19(1-2):209-212
Elevated circulating cholesterol can have profound effects on the health of an individual. Such excess cholesterol can promote
coronary artery disease, production and accumulation of β-amyloid in the brain, and possibly Alzheimer’s disease (AD). In
a clinical trial evaluating the benefit of a cholesterol-lowering drug in the treatment of AD, mean cholesterol levels at
baseline among individuals participating in the trial were found to be relatively high. Based on this observation we suggest
that cholesterol levels should be actively monitored in the elderly, as many individuals with AD are over 65 years of age
and therefore excluded by currently accepted guidelines. 相似文献
50.
Braña MF Casarrubios L Domínguez G Fernández C Pérez JM Quiroga AG Navarro-Ranninger C de Pascual-Teresa B 《European journal of medicinal chemistry》2002,37(4):301-313
A series of bis([(9-oxo-9,10-dihydroacridine-4-carbonyl)amino]alkyl) alkylamines have been prepared and their antiproliferative properties have been tested against HT-29 cell lines. Compounds 6b and 6d showed an interesting cytotoxic profile and were subjected to further cytotoxic evaluation, DNA binding properties and molecular modelling studies. The evaluation of the cytotoxic activity of compounds 6b and 6d against pairs of cisplatin-sensitive and -resistant ovarian tumour cells shows that both compounds may be endowed with interesting antitumour properties because they are able to circumvent cisplatin resistance in A2780cisR, CH1cisR and Pam 212-ras tumour cells. On the other hand, DNA binding data indicate that compounds 6b and 6d are able to intercalate stronger than acridine within the double helix. Both compounds displace ethidium bromide with an efficiency ten times higher than acridine from several linear double-stranded DNAs and induce 43 degrees unwinding in supercoiled pBR322 DNA while acridine unwinds pBR322 DNA by only 24 degrees. Altogether these data indicate that the significant conformational changes induced by compounds 6b and 6d in the double helix are due to a bis-intercalative DNA binding mode. We propose that binding to DNA through bisintercalation might be at least in part responsible for the remarkable cytotoxic properties of these acridine derivatives. The complex of 6b with d(GCGCGC)(2) in the four possible orientations that the ligand can adopt when binding to the DNA hexamer have been modelled and subjected to molecular dynamics simulations with the aim of evaluating the binding preferences of this bisintercalating agent into the DNA molecule. The predictions suggest that 6b binds to d(GCGCGC)(2) with a parallel orientation of the chromophores relative to each other and with a preference for binding through the minor groove of the hexamer. The possible relevance of these findings to the process of bisintercalation and the antitumour profile of these compounds is discussed in this paper. 相似文献