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1.
J Pain Res ; 16: 2619-2632, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37533560

RESUMO

Background: Neuropathic pain (NP) is a common and severe problem following spinal cord injury (SCI). However, its relationship with functional outcome remains unclear. Methods: A retrospective explorative analysis was performed on SCI patients admitted to a tertiary academic medical center between January 2018 and June 2022. The candidate predictor variables, including demographics, clinical characteristics and complications, were analyzed with logistic and linear regression. Spinal Cord Independence Measure (SCIM) scores at discharge and mean relative functional gain (mRFG) of SCIM were as outcome parameters. Results: A total of 140 SCI patients included for the final analysis. Among them, 44 (31.43%) patients were tetraplegics, and 96 (68.57%) patients were paraplegics; 68 (48.57%) patients developed NP, and 72 (51.43%) patients did not. Logistic and linear regression analyses of SCIM at discharge both showed that NP [OR=3.10, 95% CI (1.29,7.45), P=0.01; unstandardized ß=11.47, 95% CI (4.95,17.99), P<0.01; respectively] was significantly independent predictors for a favorable outcome (SCIM at discharge ≥ 50, logistic regression results) and higher SCIM total score at discharge (linear regression results). Besides, NP [unstandardized ß=15.67, 95% CI (8.94,22.41), P<0.01] was also independently associated with higher mRFG of SCIM scores. Furthermore, the NP group had significantly higher mRFG, SCIM total scores and subscales (self-care, respiration and sphincter management, and mobility) at discharge compared to the non-NP group. However, there were no significant differences in mRFG, SCIM total score or subscales at discharge among the NP subgroups in terms of locations (at level pain, below level pain, and both) or timing of occurrence (within and after one month after SCI). This study also showed that incomplete injury, lumbar-sacral injury level and non-anemia were significantly independent predictors for a favorable outcome, and higher mRFG of SCIM scores (except for non-anemia). Conclusion: NP appears independently associated with better functional recovery in SCI patients, suggesting the bright side of this undesirable complication. These findings may help to alleviate the psychological burden of NP patients and ultimately restore their confidence in rehabilitation.

2.
World J Gastroenterol ; 28(37): 5483-5493, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36312830

RESUMO

BACKGROUND: Upper gastrointestinal endoscopy is critical for esophageal squamous cell carcinoma (ESCC) detection; however, endoscopists require long-term training to avoid missing superficial lesions. AIM: To develop a deep learning computer-assisted diagnosis (CAD) system for endoscopic detection of superficial ESCC and investigate its application value. METHODS: We configured the CAD system for white-light and narrow-band imaging modes based on the YOLO v5 algorithm. A total of 4447 images from 837 patients and 1695 images from 323 patients were included in the training and testing datasets, respectively. Two experts and two non-expert endoscopists reviewed the testing dataset independently and with computer assistance. The diagnostic performance was evaluated in terms of the area under the receiver operating characteristic curve, accuracy, sensitivity, and specificity. RESULTS: The area under the receiver operating characteristics curve, accuracy, sensitivity, and specificity of the CAD system were 0.982 [95% confidence interval (CI): 0.969-0.994], 92.9% (95%CI: 89.5%-95.2%), 91.9% (95%CI: 87.4%-94.9%), and 94.7% (95%CI: 89.0%-97.6%), respectively. The accuracy of CAD was significantly higher than that of non-expert endoscopists (78.3%, P < 0.001 compared with CAD) and comparable to that of expert endoscopists (91.0%, P = 0.129 compared with CAD). After referring to the CAD results, the accuracy of the non-expert endoscopists significantly improved (88.2% vs 78.3%, P < 0.001). Lesions with Paris classification type 0-IIb were more likely to be inaccurately identified by the CAD system. CONCLUSION: The diagnostic performance of the CAD system is promising and may assist in improving detectability, particularly for inexperienced endoscopists.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/diagnóstico por imagem , Inteligência Artificial , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/patologia , Imagem de Banda Estreita , Endoscopia Gastrointestinal
3.
Surg Endosc ; 36(9): 6601-6608, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35118532

RESUMO

BACKGROUND AND AIM: Endoscopic submucosal dissection (ESD) has been used to remove subepithelial lesions (SELs) in recent years; however, duodenal ESD is associated with high rates of immediate or delayed bleeding and perforation. Whether ESD can be recommended for the treatment of duodenal SELs remains controversial. Therefore, we evaluated the efficacy and safety of ESD for duodenal SELs. METHODS: We conducted a retrospective cohort study in 62 patients (62 lesions) who underwent ESD for duodenal SELs between January 2012 and December 2020. The therapeutic outcomes from ESD for duodenal SELs and procedure-related complications were analyzed. RESULTS: En bloc resection and complete resection rates associated with duodenal ESD were 90.3% and 100%, respectively; four patients had a positive microscopic margin on pathologic examination. The median procedure time was 45 min (range 20-106 min). During the procedure, two patients received emergency surgery for uncontrolled bleeding and perforation, respectively. After the procedure, delayed bleeding occurred in three patients (4.8%), which was successfully managed by clipping, and delayed perforation occurred in two patients (3.2%) and needed emergency surgery. Risk factors related to complications were analyzed. Lesion size was found to be significantly associated with the complications (P = 0.028). No recurrences were detected, and no distant metastasis was observed in any patient during a median follow-up period of 45.5 months (range, 6-103 months). CONCLUSION: Duodenal ESD is relatively safe and feasible for duodenal SELs, especially for lesions no more than 2 cm in size.


Assuntos
Ressecção Endoscópica de Mucosa , Dissecação/métodos , Duodeno/cirurgia , Ressecção Endoscópica de Mucosa/efeitos adversos , Ressecção Endoscópica de Mucosa/métodos , Humanos , Estudos Retrospectivos , Resultado do Tratamento
5.
Curr Med Sci ; 41(1): 173-179, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33582923

RESUMO

The correlations between shear wave velocity (SWV) calculated from virtual touch tissue imaging quantification (VTIQ) technique and histological prognostic factors of invasive ductal carcinoma was investigated. A total of 76 breast tumors histologically confirmed as invasive ductal carcinomas were included in this study. SWV values were measured by VTIQ for each lesion preoperatively or prior to breast biopsy. The maximum values were recorded for statistical analysis. Medical records were reviewed to determine tumor size, histological grade, lymph node status and immunohistochemical results. Tumor subtypes were categorized as luminal A, luminal B, human epidermal growth factor receptor 2 (HER2) positive and triple negative. The correlations between SWV and histological prognostic factors were analyzed. It was found that tumor size showed positive association with SWV (r=0.465, P<0.001). Larger tumors had significantly higher SWV than smaller ones (P=0.001). Histological grade 1 tumors had significantly lower SWV values than those with higher histological grade (P=0.015). The Ki67 expression, tumor subtypes and lymph node status showed no statistically significant correlations with SWV, although triple negative tumors and lymph node-positive tumors showed higher SWV values. It was concluded that tumor size was significantly associated with SWV. Higher histological grade was associated with increased SWV. There was no statistically significant correlations between SWV and other histological prognostic factors.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Carcinoma Ductal/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/classificação , Neoplasias da Mama/patologia , Carcinoma Ductal/classificação , Carcinoma Ductal/patologia , Técnicas de Imagem por Elasticidade/normas , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Gradação de Tumores , Receptor ErbB-2/genética , Sensibilidade e Especificidade
6.
Huan Jing Ke Xue ; 41(5): 2301-2309, 2020 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608848

RESUMO

Fe(Ⅱ) activation persulfate (PS) is an effective method of degradation of organic pollutants, but the undesirable Fe(Ⅲ)/Fe(Ⅱ) cycle has become a restrictive factor in the Fe(Ⅱ)/PS system. The effects of sunflower-straw-derived biochar (SFBC) on an Fe(Ⅲ)/S2O82- system and the subsequent degradation of benzoic acid (BA) in water were systematically investigated. The characterization results of SFBC showed that it has a porous structure, consists of amorphous carbon, and has an abundance of surface functional groups and persistent free radicals (PFRs). The effects of critical parameters, including the initial pH, PS concentration, and dose of SFBC were also investigated. The results indicated that the degradation rate of BA in the SFBC/Fe(Ⅲ)/S2O82- system was significantly higher than that in the Fe(Ⅲ)/S2O82- system and SFBC system. The degradation efficiency of BA reached 100.00% with SFBC, BA, PS, and Fe(Ⅲ) concentrations of 2.0 g·L-1, 10.0 mg·L-1, 2.0 mmol·L-1, and 1.0 mmol·L-1, respectively, an initial pH of 3.0, and a reaction time of 90 min. Free radical quenching experiments and EPR studies demonstrated that SO4-· and ·OH were involved in the SFBC/Fe(Ⅲ)/S2O82- system, and the SO4-· was the main radical for the BA degradation. Reuse and real water matrix effects experiments suggested that SFBC had good stability and practical applicability. Mechanism analysis revealed that PFRs and-OH as the electron donor reacted with Fe(Ⅲ) to generate Fe(Ⅱ), which then activated PS for highly efficient oxidation of BA.

7.
Opt Express ; 27(19): 27385-27395, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31674600

RESUMO

In a single magneto-optical (MO) waveguide, the dispersion of guided bulk wave is reciprocal in the Voigt configuration. Here we show that the parity-time (P T) phase in two coupled MO waveguides can be nonreciprocal if the waveguides are properly biased. The nonreciprocal P T phase is closely related to the asymmetric field profile induced by the MO effect that modifies the coupling strength between adjacent waveguides. We show that it is feasible to switch between broken and conserved P T phases by simply reversing the magnetic bias or the propagating direction of wave. Theoretical analysis and numerical calculation prove our theory. This investigation highlights a flexible method in manipulating the field dynamics of waveguide arrays by using the novel properties of P T phase especially the exceptional points.

8.
BMC Neurol ; 19(1): 269, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31684893

RESUMO

BACKGROUND: To determine whether items of the Chinese version of the Montreal Cognitive Assessment Basic (MoCA-BC) could discriminate among cognitively normal controls (NC), and those with mild cognitive impairment (MCI), mild Alzheimer's disease (AD), and moderate-severe (AD), as well as their sensitivity and specificity. METHODS: MCI (n = 456), mild AD (n = 502) and moderate-severe AD (n = 102) patients were recruited from the memory clinic, Huashan Hospital, Shanghai, China. NC (n = 329) were recruited from health checkup outpatients. Five MoCA-BC item scores were collected in interviews. RESULTS: The MoCA-BC orientation test had high sensitivity and specificity for discrimination among MCI, mild AD and moderate-severe AD. The delayed recall memory test had high sensitivity and specificity for MCI screening. The verbal fluency test was efficient for detecting MCI and differentiating AD severity. CONCLUSIONS: Various items of the MoCA-BC can identify MCI patients early and identify the severity of dementia.


Assuntos
Doença de Alzheimer , Testes de Estado Mental e Demência , Doença de Alzheimer/classificação , Doença de Alzheimer/diagnóstico , China , Disfunção Cognitiva/classificação , Disfunção Cognitiva/diagnóstico , Humanos , Sensibilidade e Especificidade , Traduções
9.
Opt Express ; 27(5): 6240-6248, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30876212

RESUMO

We study the scattering of optical field by a hybridized metamaterial with properly imprinted gain. We predict that an occasionally real-eigen valued singularity in the interaction matrix of the coupled dark-bright meta-molecule would produce a high-Q resonance. This effect is demonstrated in full-wave three-dimensional finite element optical simulation. Field is efficiently amplified at this resonance. Further investigation shows that the resonance is associated with an exceptional point. The difference of this exceptional singularity from other high-Q resonances such as the spectral singularities in the scattering or transfer matrixes of parity-time symmetric systems and the bound states in the continuum is discussed. The non-Hermitian nature of the exceptional singularity promises some nonlinear applications.

10.
Opt Express ; 26(21): 27141-27152, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30469788

RESUMO

The coupling strength between two parity-time (PT) symmetric resonators determines whether the PT phase is broken or not. Here we investigate the scenario that two optical waveguides are spatially curved so that they switch periodically between unbroken and broken PT phases. We show that the existence of locally broken PT phase does not necessarily render a broken phase to waves propagating inside. Criteria are proposed to characterize the collective dynamics of wave near the Brillouin zone (BZ) edge, toward the cases of a totally broken phase, a partially broken phase, or a totally unbroken phase. We also discuss the characteristics of two special kinds of exceptional points (EPs) at the BZ edge, and show that their field patterns are displaced by half a period with each other. Full-wave numerical simulation proves our analysis. Potential applications especially these associated with EPs are discussed. This study helps us to understand how the locally PT-symmetric related eigenstate influences the globally collective dynamics of wave in spatially periodic configuration.

11.
J Huazhong Univ Sci Technolog Med Sci ; 35(4): 579-584, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26223931

RESUMO

This study aimed to examine the optimal conditions of laser-induced interstitial thermotherapy (LITT) via a single-needle delivery system, and the ablation-related pathological and ultrasonic changes. Ultrasound (US)-guided LITT (EchoLaser system) was performed at the output power of 2-4 Wattage (W) for 1-10 min in ex vivo bovine liver. Based on the results of the ex vivo study, the output power of 3 and 4 W with different durations was applied to in vivo rabbit livers (n=24), and VX2 tumors implanted in the hind limbs of rabbits (n=24). The ablation area was histologically determined by hematoxylin-eosin (HE) staining. Traditional US and contrast enhanced ultrasound (CEUS) were used to evaluate the treatment outcomes. The results showed: (1) In the bovine liver, ablation disruption was grossly seen, including a strip-like ablation crater, a carbonization zone anteriorly along the fiber tip, and a surrounding gray-white coagulation zone. The coagulation area, 1.2 cm in length and 1.0 cm in width, was formed in the bovine liver subjected to the ablation at 3 W for 5 min and 4 W for 4 min, and it extended slightly with the ablation time. (2) In the rabbit liver, after LITT at 3 W for 3 min and more, the coagulation area with length greater than or equal to 1.2 cm, and width greater than or equal to 1.0 cm, was found. Similar coagulation area was seen in the implanted VX2 carcinoma at 3 W for 5 min. (3) Gross examination of the liver and carcinoma showed three distinct regions: ablation crater/carbonization, coagulation and congestion distributed from the center outwards. (4) Microscopy revealed four zones after LITT, including ablation crater/carbonization, coagulation, edema and congestion from the center outwards. A large area with coagulative necrosis was observed around a vessel in the peripheral area with edema and hyperemia. (5) The size of coagulation was consistent well to the CEUS findings. It was concluded that EchoLaser system at low power can produce a coagulation area larger than 1.0 cm×1.0 cm during a short time period. The real-time US imaging can be used to effectively guide and assess the treatment.


Assuntos
Neoplasias Ósseas/terapia , Terapia a Laser/instrumentação , Hepatopatias/terapia , Terapia por Ultrassom/métodos , Animais , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/patologia , Bovinos , Membro Posterior/patologia , Terapia a Laser/métodos , Hepatopatias/diagnóstico por imagem , Coelhos , Resultado do Tratamento , Terapia por Ultrassom/instrumentação , Ultrassonografia
12.
Zhonghua Yi Shi Za Zhi ; 42(6): 360-5, 2012 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-23363851

RESUMO

Before the 19(th) century, ether and nitrous oxide were synthesized. However, they were just used as a kind of enjoyable things at night gatherings for their hypnotic and analgesic effect. In the 19(th) century, ether and nitrous oxide came into use in clinical anesthesia. Thereafter, more and more chemical narcotics were synthesized and applied to clinical anesthesia. In 1872, chloroform was injected into man's vein for anesthesia. In the 20(th) century, along with many kinds of barbiturates being synthesized, intravenous anesthesia got much development and application. At the same time, related techniques of anesthesia also improved. In the early 19(th) century, open inhalation anesthesia was often used. In 1900, there came a new anesthesia method by blowing into the windpipe through the cut of throat. Later on, the technique of endotracheal anesthesia and artificial respiration anesthesia (1908), the anesthetic instrument of endotracheal intubation and laryngeal mask and laryngoscope were invented. In the mid 19(th) century, the appearance of injection syringe and cocaine made local anesthesia possible. In 1880, local anesthesia also became successful. Thereafter, a variety of local anesthetic drugs were synthesized and applied, companying with various techniques of local anesthesia such as subarachnoid anesthesia (1900), sacral anesthesia (1901), epidural block (1903), plexus block (1902) and so on. In order to control the depth of anesthesia and respiration effectively, people attempted a lot so that anesthesia machine (1910), improved endotracheal anesthesia (1921), cryogenic technique (1902), controlled hypotension (1940s) and artificial hibernation (1950) came into being.

13.
Zhonghua Yi Shi Za Zhi ; 42(5): 283-7, 2012 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-23336310

RESUMO

Before the Civil War, nursing was performed by untrained nurses and female religious groups. After the outbreak of the Civil war, more women went out of the family and engaged in nursing service in military hospitals. Nursing in America transferred from religious charity activities and sporadic simple work into an indispensable profession and was developed. In the Civil War, excellent nurses saved soldiers' lives, reduced casualties and were gradually recognized by soldiers, doctors and the society. On the other hand, untrained nurses' lack of ability was exposed. The contradiction made nurses controversial and people began to consider what nursing was. Thus professional training for nurses was necessary, which caused the development of nursing education. This promoted the development of nursing education and professionalization of nursing.

14.
Artigo em Inglês | MEDLINE | ID: mdl-21632282

RESUMO

Three thiophenevinyl substituted one-, two-, and three-branched truxene π-conjugated compounds TS1, TS2 and TS3 have been prepared using a Heck reaction. Their linear absorption, single- and two-photon excited fluorescence were examined. The three analogues emit blue fluorescence at 420 nm. The number of branches has no influence on the position of the absorption maxima of the charge transfer band and fluorescence emitting maxima. However, the molar extinction coefficients of charge transfer band increase almost linearly with the number of branches. The two-photon absorption cross-section of the octupolar three-branched compound TS3 is several times that of the two-branched compound TS2 and one-branched compound TS1.


Assuntos
Fluorenos/química , Fotoquímica , Polímeros/química , Polímeros/síntese química , Tiofenos/química , Compostos de Vinila/química , Compostos de Vinila/síntese química , Fluorescência , Estrutura Molecular , Fótons , Espectrometria de Fluorescência , Tiofenos/síntese química
15.
J Pharm Anal ; 1(3): 175-183, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29403696

RESUMO

A new microfluidic system with four different microchambers (a circle and three equilateral concave polygons) was designed and fabricated using poly(dimethylsiloxane) (PDMS) and the soft lithography method. Using this microfluidic device at six flow rates (5, 10, 20, 30, 40, and 50 µL/h), the effects of microenvironmental geometry and aqueous flow on bacterial adhesion behaviors were investigated. Escherichia coli HB101 pGLO, which could produce a green fluorescent protein induced by l-arabinose, was utilized as the model bacteria. The results demonstrated that bacterial adhesion was significantly related to culture time, microenvironment geometry, and aqueous flow rates. Adhered bacterial density increased with the culture time. Initially, the adhesion occurred at the microchamber sides, and then the entire chamber was gradually covered with increased culture time. Adhesion densities in the side zones were larger than those in the center zones because of the lower shearing force in the side zone. Also, the adhesion densities in the complex chambers were larger than those in the simple chambers. At low flow rates, the orientation of adhered bacteria was random and disorderly. At high flow rates, bacterial orientation became close to the streamline and oriented toward the flow direction. All these results implied that bacterial adhesion tended to occur in complicated aqueous flow areas. The present study provided an on-chip flow system for physiological behavior of biological cells, as well as provided a strategic cue for the prevention of bacterial infection and biofilm formation.

16.
Ying Yong Sheng Tai Xue Bao ; 21(12): 3225-30, 2010 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-21443013

RESUMO

A total of thirteen fungal strains with higher arsenic (As)-tolerance ability were isolated from six As-contaminated soil samples collected from the mining areas of Shimen County and Chenz-hou City in Hunan Province. Among the strains isolated, Penicillin janthinellum, Fusarium oxysporum, and Trichoderma asperellum had the highest As-tolerance ability, based on the morphological identification and phylogenetic analysis. Culture experiment showed that on the solid plates with 30,000, 30,000, and 20,000 mg x L(-1) of As, P. janthinellum, F. oxysporum, and T. asperellum had a better colony growth, and after cultured in the liquid medium with 0-50, 0-50, and 0-80 mg x L(-1) of As for 2 days, respectively, the dry mycelia masses of the three strains all increased with increasing As concentration. When the As concentration reached 50, 50, and 80 mg x L(-1), respectively, the fungal biomass of F. oxysporum, T. asperellum, and P. janthinellum increased significantly, compared with CK. High concentration As had no significant effects on the sporalation of the three fungal strains.


Assuntos
Arsênio/metabolismo , Fusarium/efeitos dos fármacos , Penicillium/efeitos dos fármacos , Poluentes do Solo/metabolismo , Trichoderma/efeitos dos fármacos , Arsênio/análise , Biodegradação Ambiental , Tolerância a Medicamentos , Fusarium/classificação , Fusarium/isolamento & purificação , Penicillium/classificação , Penicillium/isolamento & purificação , Microbiologia do Solo , Poluentes do Solo/análise , Trichoderma/classificação , Trichoderma/isolamento & purificação
17.
Zhonghua Yi Shi Za Zhi ; 39(5): 261-5, 2009 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-19930949

RESUMO

The medical education of America gradually became one of the models of the advanced medical education throughout the world in the beginning of 20th century. The medical educational revolution in America led by the report of Flexner was an important foundation for the successful development of medical education in America. The occurrence of the Flexner Revolution was closely connected with the transformation of medical concepts and educational ideas which were led by the revolution in various social factors. So we can say that the Flexner Revolution was led by ideas.


Assuntos
Educação Médica/história , História do Século XX , Estados Unidos
18.
J Org Chem ; 73(20): 8101-3, 2008 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-18816140

RESUMO

Chiral N-hetereocyclic carbenes were found to be efficient catalysts for the formal [2 + 2] cycloaddition reactions of alkyl(aryl)ketenes with 2-oxoaldehydes to afford beta-lactones with alpha-quaternary-beta-tertiary stereocenters in high yields with good diastereoselectivities and excellent enantioselectivities (up to 99% ee). Both alkyl(aryl)ketenes and diarylketene worked well in this reaction.


Assuntos
Aldeídos/química , Etilenos/química , Cetonas/química , Metano/análogos & derivados , Catálise , Metano/química , Estereoisomerismo
20.
Org Lett ; 10(2): 277-80, 2008 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-18085789

RESUMO

N-heterocyclic carbenes (NHCs) were demonstrated to be efficient catalysts for the Staudinger reaction of ketenes with N-tosyl, N-benzyloxycarbonyl, or N-tert-butoxycarbonyl imines. Chiral NHC 8b, conveniently prepared from L-pyroglutamic acid, catalyzed the reactions of arylalkylketenes with a variety of N-tert-butoxycarbonyl arylimines to give the corresponding cis-beta-lactams in good yields with good diastereoselectivities and excellent enantioselectivities (up to 99% ee). Two possible catalytic pathways, initiated by the addition of NHC to ketenes or imines, were discussed.


Assuntos
Etilenos/química , Iminas/química , Cetonas/química , beta-Lactamas/química , beta-Lactamas/síntese química , Catálise , Estrutura Molecular , Estereoisomerismo
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