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81.
82.
Jameel Ali Subodh Kumar Subash Gautam Anne Sorvari Mahesh C. Misra 《The Indian journal of surgery》2015,77(2):227-231
The Rural Trauma Team Development Course (RTTDC) was devised to optimize trauma resuscitation training in under-resourced rural institutions. This program appears ideal for India because of its dense traffic, large population, and high frequency of rural trauma. We report on the feasibility and desirability of introducing RTTDC in India. An instructor course for 20 faculties and a provider course for 23 were conducted in New Delhi, India. The courses were evaluated by multiple choice question (MCQ) performance, by rating the modules on a three-point scale (1 = very relevant, 2 = relevant, and 3 = not relevant) for communication skills, principles of performance improvement and patient safety (PIPS), and clinical scenarios. Evaluation questionnaires including desirability of promulgation in India were completed using a five-point Likert Scale (1 = strongly agree, 2 = agree, 3 = neutral, 4 = disagree, and 5 = strongly disagree). Overall written comments were also provided. Both faculty and providers improved post-course MCQ scores (p?<?0.05) with lower scores in the provider group. Seventy-eight percent faculty and 74 % providers rated the communication module very relevant. PIPS was rated very relevant by 72 % faculty and 65 % providers. There were over 150 comments, generally positive with over 90 % of both faculty and providers rating strongly agree to agree that the course be promulgated widely in India. The RTTDC including plans for promulgation was enthusiastically received in India, and its potential for improving trauma care including communication skills and PIPS appears excellent. 相似文献
83.
The excitement of drug-eluting stents and their promise for reduced restenosis rates have been tempered by recent reports of stent thrombosis. The mechanism of stent thrombosis is multifactorial but appears to be related to delayed endothelialization and healing, late stent malapposition, and antiplatelet resistance. The most important risk factor appears to be the discontinuation of dual antiplatelet therapy. The data from clinical trials suggest that drug-eluting stents are associated with increased incidence of death or myocardial infarction compared with bare metal stents at long-term follow-up, suggesting that the window of thrombotic risk with drug-eluting stents may extend far beyond that for bare metal stents. Measures to possibly decrease the incidence of stent thrombosis include improvements in antiplatelet regimens and newer generation of drug-eluting stents which have biodegradable polymers or are polymer-free. In addition, percutaneous coronary intervention with bare metal stents in patients may be helpful in those known to be intolerant or noncompliant to antiplatelet therapy, have planned procedures or surgeries, or have overwhelming risks which may require discontinuation of dual antiplatelet therapy. 相似文献
84.
A N Pronin N Gautam 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(13):6220-6224
Signal-transducing guanine nucleotide-binding proteins (G proteins) are made up of three subunits, alpha, beta, and gamma. Each of these subunits comprises a family of proteins. The rules for association between members of one family with members of another to form a multimer are not known; it is not clear whether associations are specific or nonspecific. Other than transducin (Gt), the G protein in rod photoreceptors, most purified G proteins contain more than one subtype of beta or gamma subunits. The Gt alpha subunit is associated only with beta 1 and gamma 1. It is not known whether this specificity is due to the differential expression of these subunit types in a cell type or due to intrinsically different affinities between different beta and gamma subunit types. We have used a transfected cell assay system to examine the association of the beta 1, beta 2, and beta 3 proteins with the gamma 1 and gamma 2 proteins. Results show that gamma 1 does not associate with beta 2 and that beta 3 does not associate with gamma 1 or gamma 2. Differences in affinities between types of G protein subunits will impose restrictions on the formation of certain heterotrimers and determine which G protein will be active in a cell. A chimeric molecule of beta 1 and beta 2 was used to broadly map the regions on these subunits that determine specificity of association. 相似文献
85.
Gene transfer to primary normal and malignant human hemopoietic progenitors using recombinant retroviruses 总被引:10,自引:0,他引:10
To study the feasibility of using retroviruses for gene transfer into human hemopoietic cells, various cell types were exposed to virus carrying the gene for neomycin resistance (neor). In preliminary studies using K562 cells as targets, we found that high viral titer and co-cultivation with viral producer cells rather than incubation in medium exposed to viral producer cells were important variables for achieving high frequencies of G418 resistant (G418r) colonies. The maximum frequency of G418r K562 colonies after co-cultivation with cells producing a neor virus titer of 4 X 10(6) cfu/mL was 60%. When primary human progenitors from normal marrow, fetal liver, or chronic myelogenous leukemia blood were exposed to high titer viral stocks, both with and without helper virus, under conditions optimized for K562 cells, maximum frequencies of G418r colonies were 3% to 16% for granulocyte macrophage progenitors and 2% to 6% for primitive erythroid progenitors. The presence of the neor gene in both G418r K562 and primary hemopoietic colonies was verified by Southern blot. Expression of the neor gene was shown by RNA spot blot. These data demonstrate efficient transfer and expression of the neor gene in both K562 cells and primary human hemopoietic cells from normal and leukemic individuals. 相似文献
86.
S K Bansal P C Gautam S P Sahi S K Basu J M Lennox A J Warrington 《Age and ageing》1987,16(5):279-284
Ninety-two consecutive elderly patients suffering from acute gastrointestinal bleeding were studied over a 3-year period. All were admitted to a specially designated Geriatric/Surgical Ward under the care of consultant physicians in geriatric medicine. The nurses were trained to look after acute surgical and geriatric patients. Patients were aged between 65 and 93 years. All were managed jointly by the surgeons and physicians. Only 13 needed emergency surgery which was preceded by urgent endoscopy. The rest were managed conservatively with intravenous cimetidine and blood transfusions as required. The overall mortality was low at 5.4%. It is concluded that in a series of elderly patients with acute gastrointestinal bleeding the mortality was not high in a unit where the management was conservative and there was joint care between geriatricians and surgeons. 相似文献
87.
88.
Hemostatic gene polymorphisms and the prevalence of thrombotic complications in polycythemia vera and essential thrombocythemia. 总被引:3,自引:0,他引:3
Vahid Afshar-Kharghan José A López Leigh A Gray Arnoldo Padilla Gautam Borthakur Stacy C Roberts Rajiv K Pruthi Ayalew Tefferi 《Blood coagulation & fibrinolysis》2004,15(1):21-24
Patients with polycythemia vera and essential thrombocythemia are at risk for thrombotic and bleeding complications. Currently, no diagnostic test can predict thrombohemorrhagic complications. In a prospective study of 86 patients with polycythemia vera (43 patients) or essential thrombocythemia (43 patients), we examined the possible role of polymorphisms of platelet adhesion receptors [glycoprotein (GP) Ibalpha, GPIa, GPIIIa) and clotting factor II (prothrombin's G20210A mutation) and clotting factor V (Leiden mutation) in determining the risk of thrombotic or bleeding complications. Except for an association between vasomotor symptoms and prothrombin mutation (P < 0.001), no significant correlation between polymorphism of clotting factors and thrombohemorrhagic complications was identified. When the entire patient cohort was considered, the polymorphisms of platelet adhesion receptors were not associated with the risk for thrombotic or bleeding complications. However, among patients with polycythemia vera, the presence of the PlA2 allele of GPIIIa was associated with an increased risk of arterial thrombosis. In view of previous studies linking the presence of the PlA2 allele of GPIIIa to a higher risk for coronary artery thrombosis, our data have physiologic relevance. However, they need to be confirmed in a larger study. 相似文献
89.
Vini Gautam Jack Drury Julian M. C. Choy Christian Stricker Hans-A. Bachor Vincent R. Daria 《Biomedical optics express》2015,6(10):4027-4036
We optimize two-photon imaging of living neurons in brain tissue by temporally gating an incident laser to reduce the photon flux while optimizing the maximum fluorescence signal from the acquired images. Temporal gating produces a bunch of ~10 femtosecond pulses and the fluorescence signal is improved by increasing the bunch-pulse energy. Gating is achieved using an acousto-optic modulator with a variable gating frequency determined as integral multiples of the imaging sampling frequency. We hypothesize that reducing the photon flux minimizes the photo-damage to the cells. Our results, however, show that despite producing a high fluorescence signal, cell viability is compromised when the gating and sampling frequencies are equal (or effectively one bunch-pulse per pixel). We found an optimum gating frequency range that maintains the viability of the cells while preserving a pre-set fluorescence signal of the acquired two-photon images. The neurons are imaged while under whole-cell patch, and the cell viability is monitored as a change in the membrane’s input resistance.OCIS codes: (170.3880) Medical and biological imaging, (170.3660) Light propagation in tissues, (140.0140) Lasers and laser optics, (170.2520) Fluorescence microscopy, (170.6930) Tissue, (110.0110) Imaging systems 相似文献
90.
Subacute posttraumatic ascending myelopathy is a rare disorder, unrelated to syrinx formation or mechanical
instability, which may gradually emerge within the first 1-2 weeks after a spinal cord injury and may lead to diagnostic and prognostic dilemmas. We present a case of 24-year-old female with unstable wedge compression fracture of L1 vertebrae with signal changes in the upper lumbar cord causing complete paraplegia below D9 with bladder and bowel involvement. In the subsequent week, she developed a delayed progressively increasing neurological deficit with cord signal abnormality on MRI extending cephalad from the injury site to the upper dorsal cord. The patient had no initial clinical improvement initially but showed a delayed recovery over months. 相似文献