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排序方式: 共有3155条查询结果,搜索用时 26 毫秒
1.
Dr. Raysa Khan Tareque Dr. Storm Hassell-Hart Dr. Tobias Krojer Dr. Anthony Bradley Dr. Srikannathasan Velupillai Dr. Romain Talon Dr. Michael Fairhead Dr. Iain J. Day Kamlesh Bala Dr. Robert Felix Dr. Paul D. Kemmitt Prof. Paul Brennan Prof. Frank von Delft Dr. Laura Díaz Sáez Prof. Kilian Huber Prof. John Spencer 《ChemMedChem》2020,15(24):2513-2520
Combined photochemical arylation, “nuisance effect” (SNAr) reaction sequences have been employed in the design of small arrays for immediate deployment in medium-throughput X-ray protein–ligand structure determination. Reactions were deliberately allowed to run “out of control” in terms of selectivity; for example the ortho-arylation of 2-phenylpyridine gave five products resulting from mono- and bisarylations combined with SNAr processes. As a result, a number of crystallographic hits against NUDT7, a key peroxisomal CoA ester hydrolase, have been identified. 相似文献
2.
Wyatt L. Brown Douglas A. Day Harald Stark Demetrios Pagonis Jordan E. Krechmer Xiaoxi Liu Derek J. Price Erin F. Katz Peter F. DeCarlo Catherine G. Masoud Dongyu S. Wang Lea Hildebrandt Ruiz Caleb Arata David M. Lunderberg Allen H. Goldstein Delphine K. Farmer Marina E. Vance Jose L. Jimenez 《Indoor air》2021,31(1):141-155
Understanding the sources and composition of organic aerosol (OA) in indoor environments requires rapid measurements, since many emissions and processes have short timescales. However, real-time molecular-level OA measurements have not been reported indoors. Here, we present quantitative measurements, at a time resolution of five seconds, of molecular ions corresponding to diverse aerosol-phase species, by applying extractive electrospray ionization mass spectrometry (EESI-MS) to indoor air analysis for the first time, as part of the highly instrumented HOMEChem field study. We demonstrate how the complex spectra of EESI-MS are screened in order to extract chemical information and investigate the possibility of interference from gas-phase semivolatile species. During experiments that simulated the Thanksgiving US holiday meal preparation, EESI-MS quantified multiple species, including fatty acids, carbohydrates, siloxanes, and phthalates. Intercomparisons with Aerosol Mass Spectrometer (AMS) and Scanning Mobility Particle Sizer suggest that EESI-MS quantified a large fraction of OA. Comparisons with FIGAERO-CIMS shows similar signal levels and good correlation, with a range of 100 for the relative sensitivities. Comparisons with SV-TAG for phthalates and with SV-TAG and AMS for total siloxanes also show strong correlation. EESI-MS observations can be used with gas-phase measurements to identify co-emitted gas- and aerosol-phase species, and this is demonstrated using complementary gas-phase PTR-MS observations. 相似文献
3.
Z Abbas AH Khan SM Jafri SS Hamid SH Shah S Abid JA Qureshi 《Canadian Metallurgical Quarterly》1997,12(11):703-706
The authors compared in a controlled clinical study two groups of patients after a first renal transplantation treated by triple drug immunosuppressive therapy. In a group of 31 patients the triple combination comprised Sandimmune Neoral. In the control group there were 30 patients who received Sandimmune. No differences were found between the two groups as regards the effectiveness of this treatment and the authors did not confirm a lower incidence of rejections described in patients treated with Sandimmune Neoral. They confirmed, however, a lower interindividual variability of Cy-A levels assessed specifically in patients treated with Sandimmune Neoral. 相似文献
4.
LJ Huang K Durick JA Weiner J Chun SS Taylor 《Canadian Metallurgical Quarterly》1997,94(21):11184-11189
Subcellular localization directed by specific A kinase anchoring proteins (AKAPs) is a mechanism for compartmentalization of cAMP-dependent protein kinase (PKA). Using a two-hybrid screen, a novel AKAP was isolated. Because it interacts with both the type I and type II regulatory subunits, it was defined as a dual specific AKAP or D-AKAP1. Here we report the cloning and characterization of another novel cDNA isolated from that screen. This new member of the D-AKAP family, D-AKAP2, also binds both types of regulatory subunits. A message of 5 kb pairs was detected for D-AKAP2 in all embryonic stages and in all adult tissues tested. In brain, skeletal muscle, kidney, and testis, a 10-kb mRNA was identified. In testis, several small mRNAs were observed. Therefore, D-AKAP2 represents a novel family of proteins. cDNA cloning from a mouse testis library identified the full length D-AKAP2. It is composed of 372 amino acids which includes the R binding fragment, residues 333-372, at its C-terminus. Based on coprecipitation assays, the R binding domain interacts with the N-terminal dimerization domain of RIalpha and RIIalpha. A putative RGS domain was identified near the N-terminal region of D-AKAP2. The presence of this domain raises the intriguing possibility that D-AKAP2 may interact with a Galpha protein thus providing a link between the signaling machinery at the plasma membrane and the downstream kinase. 相似文献
5.
6.
RB Singh R Beegom S Ghosh MA Niaz V Rastogi SS Rastogi NK Singh S Nangia 《Canadian Metallurgical Quarterly》1997,11(10):679-685
OBJECTIVES: To determine age-specific prevalence of hypertension and blood pressure (BP) levels in relation to diet and lifestyle factors in North Indians. DESIGN AND SETTING: Cross-sectional survey in 20 randomly selected streets in Moradabad, North India. SUBJECTS AND METHODS: A total of 1806 subjects from North India (904 males and 902 females) age range 25-64 years. The survey methods were as follows: dietary diaries for 7 days food intake record; BP measurements; physician administered questionnaire and anthropometric measurements. Diagnosis of hypertension was based on new World Health Organization/International Society of Hypertension (WHO/ISH) criteria. Risk factors were assessed based on WHO guidelines. RESULTS: The prevalence of hypertension according to WHO/ISH criteria was 23.7% and by old WHO criteria 13.3%. In the WHO/ISH hypertensive group, isolated diastolic hypertension was present in 47.3% males and 40.6% females. Males have a slightly higher prevalence than females in the young age group, however, the prevalence rates are comparable in the older age groups. In both sexes, the prevalence rates and BP level increased with older age. Multivariate analysis revealed that age, higher body mass index, central obesity and higher socioeconomic status were independently and strongly associated with hypertension in both sexes. Higher dietary fat and salt intake and lower physical activity were weakly but significantly associated with hypertension. CONCLUSION: Association of higher socioeconmic status, higher body mass index and central obesity in North Indian adults with higher fat intake, lower physical activity and higher prevalence and level of hypertension indicate that these populations may benefit by decreasing the dietary fat intake and increasing physical activity, with an aim to decrease central obesity for decreasing hypertension in North Indians. 相似文献
7.
8.
BACKGROUND: There is controversy over whether colonization with drug-resistant organisms is a contraindication to lung transplantation. METHODS: We undertook a retrospective review of the results of lung transplantation for patients with cystic fibrosis (CF) at Duke University Medical Center. RESULTS: As of May 1996, 21 patients with CF underwent bilateral lung transplantation. The first patient died within 24 h of transplantation from sepsis due to Stenotrophomonas maltophilia. Of the remaining 20 patients, 17 (85%) are alive and in stable condition. The three deaths were related primarily to bronchiolitis obliterans at 4 and 18 months in two patients and to cytomegalovirus pneumonitis at 5 months in the other patient. The 17 surviving patients have been followed up for a mean of 13 months (range, 0.5 to 34 months). Most of them were colonized and infected with multidrug-resistant organisms before transplantation. Following transplantation, 11 patients had complications from infections. One patient had bacteremia due to a panresistant Burkholderia cepacia and was treated successfully. Two patients had bacteremia and wound infection due to Burkholderia gladioli, previously thought to be pathogenic only in plants. Both patients were treated successfully. Of the six patients with Aspergillus fumigatus isolated from cultures before transplantation, only one had invasive disease following transplantation and responded to treatment. CONCLUSION: The organisms present before transplantation were not the primary cause of mortality in our patient population. Our findings suggest that lung transplantation should be considered in CF patients infected with multidrug-resistant organisms. 相似文献
9.
MJ Day 《Canadian Metallurgical Quarterly》1997,38(9):393-403
Data are presented from 30 cats and 36 dogs in which thymic disease was recognised clinically or on postmortem examination. The diagnoses included thymic lymphoma (19 cats, 12 dogs), thymoma (five cats, 18 dogs), thymic branchial cyst formation or cystic change (one cat, four dogs), thymic hyperplasia (two cats), congenital hypoplasia (one cat, one dog), thymic haemorrhage (one cat, one dog) and thymic amyloidosis (one cat). Thymic lymphoma occurred in younger dogs and cats, and was recorded equally among domestic shorthaired and purebred (especially Siamese) cats. Eight cats with thymic lymphoma were tested for feline leukaemia virus and four were positive. Thymoma occurred more frequently in older cats and dogs, and in Labradors and German shepherd dogs. Thymic tumours were associated with paraneoplastic hypercalcaemia (six dogs), megaoesophagus (two dogs) or interface dermatitis with basement membrane immune complex deposition (one cat). Non-neoplastic thymic diseases were associated with myasthenia gravis (one cat), pemphigus foliaceus (one cat) and superficial necrolytic dermatitis (one cat). 相似文献
10.
At present, the preferred tool for parameter estimation in compartmental analysis is an iterative procedure; weighted nonlinear regression. For a large number of applications, observed data can be fitted to sums of exponentials whose parameters are directly related to the rate constants/coefficients of the compartmental models. Since weighted nonlinear regression often has to be repeated for many different data sets, the process of fitting data from compartmental systems can be very time consuming. Furthermore the minimization routine often converges to a local (as opposed to global) minimum. In this paper, we examine the possibility of using artificial neural networks instead of weighted nonlinear regression in order to estimate model parameters. We train simple feed-forward neural networks to produce as outputs the parameter values of a given model when kinetic data are fed to the networks' input layer. The artificial neural networks produce unbiased estimates and are orders of magnitude faster than regression algorithms. At noise levels typical of many real applications, the neural networks are found to produce lower variance estimates than weighted nonlinear regression in the estimation of parameters from mono- and biexponential models. These results are primarily due to the inability of weighted nonlinear regression to converge. These results establish that artificial neural networks are powerful tools for estimating parameters for simple compartmental models. 相似文献