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Different from electronically matched 1,4- and 1,6-additions, herein, we disclose an electronically mismatched 1,5-conjugate addition process with oximes as the nucleophiles. By this design, the oxime moieties are readily introduced to the γ-position of the electron-deficient substrates in good yields, excellent regioselectivities, and high enantioselectivities. The corresponding allyl oximes are also conveniently transformed into a series of valuable enantioenriched skeletons.
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The straightforward construction of stereogenic centers bearing unprotected functional groups, as in nature, has been a persistent pursuit in synthetic chemistry. Abundant applications of free enantioenriched allyl alcohol and allyl hydroxylamine motifs have made the asymmetric hydration and hydroaminoxylation of conjugated dienes from water and hydroxylamine, respectively, intriguing and efficient routes that have, however, been unachievable thus far. A fundamental challenge is the failure to realize transition-metal-catalyzed enantioselective C-O bond constructions via hydrofunctionalization of conjugated dienes. Here, we perform a comprehensive study toward the stereoselective formal hydration and hydroaminoxylation of conjugated dienes by synthesizing a set of new P,N-ligands and identifying an aryl-derived oxime as a surrogate for both water and hydroxylamine. Asymmetric hydroalkoxylation with new P,N-ligands is also elucidated. Furthermore, versatile derivatizations following hydration provide indirect but concise routes to formal hydrophenoxylation, hydrofluoroalkoxylation, and hydrocarboxylation of conjugated dienes that have been unreported thus far. Finally, a ligand-to-ligand hydrogen transfer process is proposed based on the results of preliminary mechanistic experiments.
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At present, the main treatment for strabismus is still surgical treatment, but there is no unified standard for the evaluation of the timing of surgery. This study mainly explores the clinical effects of using meta-analysis of intelligent image sensors combined with visual training to treat children with intermittent exotropia. Cochrane systematic reviews collect, evaluate, and synthesize an increasing number of original clinical research results to obtain the comprehensive effect of relevant interventions, so as to provide real and reliable evidence for health decision-making and clinical practice. It uses scientific, clear, and reproducible research methods to reduce the influence of biased factors, so it is different from traditional reviews. Cochrane systematic reviews are especially suitable for certain interventions when the pros and cons of interventions are difficult to determine based on the results of a single clinical study or when there are large differences in the clinical application process. Poor quality systematic reviews can mislead policymakers and clinicians. In the meta-analysis, the Cochrane systematic evaluation method of evidence-based medicine was used to comprehensively search the published literature research on the treatment of intermittent exotropia with vision training. Using the Cochrane system evaluation method, computer search of CENTRAL, MEDLINE, Embase, Chinese Biomedical Literature Database, Chinese Journal Full-text Database, manual retrieval of relevant conference documents, and inclusion of all clinical trial documents of visual training in children with intermittent exotropia was conducted. Patients with intermittent exotropia were selected, simultaneous vision, fusion function, and far stereo vision with the same vision machine were measured, and near stereo vision with a stereo vision chart was measured. The number of simultaneous vision, fusion function, and distance and near stereo vision "with" and "without" cases were recorded for all patients, and the relationship with age of onset, type of strabismus, degree of strabismus, and degree of control was counted. Among them, 91 patients who underwent strabismus correction surgery were followed up for at least 6 months with correct eye position. The presence or absence of simultaneous vision, fusion function, far stereo vision, and near stereo vision were recorded and compared with preoperative. The number of recovery and nonrecovery cases was recorded, and the relationship between the age of operation, the type of strabismus, the degree of strabismus, and the degree of control was counted. It was statistically analyzed by SPSS22.0. The results of the meta-analysis showed that in terms of the effective rate of fundus lesions, the visual training group was better than the nontraining group, and the difference between the two groups was statistically significant (RR = 1.32, 95% CI: (1.25, 1.40), P < 0.0001). This study provides guidance for the early rehabilitation of children with intermittent exotropia.
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Exotropia , Estrabismo , Criança , China , Doença Crônica , Meios de Contraste , Exotropia/cirurgia , Humanos , Imagem MolecularRESUMO
OBJECTIVE: To explore the effect of applying binocular visual training after slanted lateral rectus recession on orthophoric rate and binocular visual function recovery on patients with convergence insufficiency-type intermittent exotropia (CI-IXT). METHODS: A total of 76 CI-IXT child patients treated at the Strabismus and Pediatric Ophthalmology Department of our hospital from June 2019 to June 2020 were selected as the research objects, and those who met the inclusion criteria were equally divided into group A (63 eyes) and group B (61 eyes) according to the sealed envelope randomization. All child patients accepted the slanted lateral rectus recession, and after that, those in group A accepted the binocular visual training and those in group B accepted the conventional visual function rehabilitation training, so as to compare their position of eye, the best corrected visual acuity, etc., after training for statistical analysis. RESULTS: Compared with group B after one month of surgery, group A had significantly less patients with grade I binocular vision function (P < 0.001) and more patients with grade II and III vision function (P < 0.05); between group A and group B, after 3 months and 6 months of treatment, the number of eyes with normal stereoscopic vision was significantly higher in group A (P < 0.05); at 15 days, 1 month, 3 months, and 6 months of treatment, the visual strain scores of group A were significantly lower (P < 0.001); after treatment, the number of orthophoria eyes was significantly higher in group A (P < 0.001), while the numbers of overcorrected eyes and undercorrected eyes were significantly higher in group B (P < 0.001); and the total incidence rate of adverse reactions was significantly lower in group A (P < 0.05). CONCLUSION: Applying binocular visual training to child patients with CI-IXT after slanted lateral rectus recession can promote the recovery of binocular vision and ensure higher safety, and further study will help to establish a better solution for the affected children.
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The formation mechanism of anodic TiO2 nanotubes remains to be unclear till now. Many researchers study the influence of temperatures above 0 °C instead of below 0 °C. Few papers before have explained the relationship between the current-time curve and the morphology of the nanotubes. In this study, the innovative 'oxygen bubble model' and the ionic current and electronic current theories were introduced to explain the growth of nanotubes below 0 °C. The length of anodic TiO2 nanotubes at 15 °C, 0 °C, -10 °C were 1.28 µm, 0.93 µm and 0.21 µm, respectively, but the diameter of anodic TiO2 nanotubes was almost the same, at about 164 nm. When the temperature was low, the magnitude of electronic current and the ionic current was small, the mold effect was weak and nanotubes could not be formed. At the same time, this study shows that the dissolution reaction of the field-assisted solution theory has no electron gain or loss, and it has nothing to do with the current, which negates the field-assisted dissolution theory. A novel two-step anodization was used to verify the conclusion. It was found that nanotubes could be obtained when the anodizing current was decreasing or increasing. Also, ginseng-shaped nanotubes are formed at a particular voltage sequence. Based on the 'oxygen bubble model' and the ionic current and electronic current theories, the formation process of nanotubes of two-step anodization is explained clearly.
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PURPOSE: To report on an improved botulinum toxin injection with conjunctival microincision for beginners, and to determine the effectiveness of botulinum toxin A (BTXA) in the treatment of patients with acute acquired comitant esotropia (AACE). METHODS: Medical records of 29 AACE patients were retrospectively analyzed. BTXA was injected into the unilateral or bilateral medial rectus muscle with conjunctival microincision without electromyographic guidance. Success was defined as total horizontal deviation ≤10 prism diopters (PD) and evidence of binocular vision. RESULTS: Twenty-nine patients were included, of whom 22 were male and 7 were female. The mean age at onset was 14.2 ± 7.4 (range, 4-34) years. The mean time from onset of AACE to injection was 18.4 ± 20.3 (range, 1-96) weeks. All patients completed at least 6 months of follow-up, and the mean follow-up after BTXA injection was 12.3 ± 4.8 months (range, 7-24 months). Neurological evaluation and brain magnetic resonance imaging (MRI) were unremarkable in all patients. The mean spherical equivalent refraction was -1.22 ± 2.85D and -0.97 ± 2.80D in the right and left eyes, respectively. Mean preinjective esotropia was 38.4 ± 18.9 PD (range, +10-+80 PD) at near and 40.2 ± 17.7 PD (range, +20-+80 PD) at far distance. The mean angle of deviation at 6 months after injection was 0.6 ± 4.1 PD (range, -3-+15 PD) at near and 3.0 ± 5.9 PD (range, 0-+20 PD) at far distance. There was significant difference in the angle of deviation at near and far fixation between pre-BTXA and post-BTXA 6 months (p < 0.001, p < 0.001, resp.). There was no significant difference in the angle of deviation at near and far fixation between post-BTXA 6 months and post-BTXA at final follow-up (p = 0.259 and 0.326, resp.). Mean stereoacuity improved from 338 to 88 arc seconds. During the follow-up period, 5 of 29 patients had recurrent esotropia. Two patients refused all further treatment, and the other 3 patients required incisional strabismus surgery. The success rates were 86.2% (25/29) at 6 months and 82.8% (24/29) at final follow-up. CONCLUSION: Conjunctival microincision injection of botulinum toxin is a practical and safe method for beginners to locate an extraocular muscle, which is as effective as the traditional methods. Botulinum toxin injection can be preferred as the first-line treatment for AACE patients with potential binocular vision.
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BACKGROUND: Dacryoliths in lacrimal gland ductule are a rare condition and an unusual cause of conjunctivitis. Here we report a case with a large lacrimal gland ductule stone with an unique hairy nucleus. CASE PRESENTATION: A 38-year-old female presented with a red left eye for one month. Physical examination revealed an inflammatory granuloma in the lateral canthus and a fistula with purulent secretion. Antibiotics did not ameliorate the symptoms. After we incised the fistula, a huge dacryolith (10 mm × 5 mm × 3 mm) was identified at the end of the dilated lacrimal gland ductule and was removed surgically. Histopathologic examination showed a hairy nucleus surrounded by lamellar structure. The symptoms were resolved in 2 weeks after dacryolith extraction. The formation of the hair-centered dacryolith might be associated with the patient's personal history of being a rabbit raiser for years. CONCLUSION: We should be aware of lacrimal gland ductule dacryolith as a rare cause of conjunctivitis. The relationship between dacryolithiasis and fur-bearing animal raising warrants further investigation.
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Cálculos/diagnóstico , Dacriocistorinostomia/métodos , Aparelho Lacrimal/patologia , Obstrução dos Ductos Lacrimais/etiologia , Adulto , Cálculos/complicações , Cálculos/cirurgia , Feminino , Humanos , Aparelho Lacrimal/cirurgia , Obstrução dos Ductos Lacrimais/diagnóstico , Doenças RarasRESUMO
In this study, a series of novel pigments based on V5+ doped BiPO4 have been prepared for the first time via a facile hydrothermal method and characterized using several analytical techniques, such as X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), ultraviolet-visible-near-infrared (UV-vis-NIR) spectrometry, the Commission International de l'Eclairage (CIE) L*a*b* color scales and thermogravimetry and differential thermal analysis (TG-DTA). The investigation demonstrated that the synthesized pigments of BiP1-x V x O4 (x = 0.00, 0.01, 0.05, 0.08, 0.10, 0.15) had a monazite-type phase structure and were about 0.25-2 µm in size. Meanwhile, the substitution of V5+ for P5+ in BiPO4 resulted in the band gap of the pigments varying from 3.657 to 3.244 eV and its mechanism was explained by charge-transfer and energy band theory, while the color changed from white to yellow. More importantly, the V5+ doped pigments possessed high NIR reflectance (>72%) and NIR solar reflectance (≥75.64%) in the range 700-2500 nm. Moreover, coatings colored with synthetic pigments have higher NIR solar reflectance (≥78.59%) than conventional pigments. Additionally, the pigments showed good thermal/chemical stabilities in high-temperature/acid/alkaline tests. In conclusion, the pigments have the potential to be applied as "cool pigments" to reduce energy consumption.
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The impact of the high-temperature phase change material on conventional infrared decoy's combustion performance and infrared radiation characteristics was studied. The selected high-temperature phase change materials did not reduce infrared radiation in the 3-5 microm or 8-14 microm band of infrared decoy, while extended the burning time, and reduced the burning rate of the grain, thus prolonged the effective interference time of IR decoy. The results show the phase change material is effective infrared decoy functional additives.
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OBJECTIVE: To study the clinicopathologic features of myeloid sarcoma and to evaluate the role of immunohistochemical study in diagnosis of this entity. METHODS: Eighty-two cases of myeloid sarcoma were retrieved from the archives of Department of Pathology, West China Hospital of Sichuan University during the period from January, 1990 to February, 2005. The morphologic features were reviewed and classified according to the 2001 WHO classification for hematopoietic and lymphoid tissue tumors. Immunohistochemical study using a panel of 11 antibodies was performed on 73 cases. The survival data were collected and analyzed by SPSS 10.0. RESULTS: The median age of patients was 35.5 years. The male-to-female ratio was 1.4:1. The sites of occurrence included lymph node (43.1%), skin (16.7%), nose (7.8%), soft tissue (7.8%) and bone (6.9%). Fifty-one cases (62.2%) represented myeloid sarcoma associated with an underlying myeloproliferative disorder and 25 cases (30.5%) represented solitary myeloid sarcoma. As for the morphology, 79 cases (96.3%) were granulocytic sarcoma, including 41 cases (51.9%) blastic type, 25 cases (31.6%) immature type and 13 cases (16.5%) differentiated type. The other 3 cases (3.7%) were monoblastic sarcoma. Immature eosinophils were found in 51 cases (64.6%) of granulocytic sarcoma, among which 13 cases (31.7%) were of blastic type. Immunohistochemical study showed that 95.9% cases (70/73) were positive for myeloperoxidase, 95.5% (63/66) for lysozyme, 95.2% (60/63) for CD68 (KP1), 90.8% (59/65) for leukocyte common antigen, 85.7% (54/63) for CD43, 77.8% (49/63) for CD117, 58.7% (37/63) for CD99, 54.0% (34/63) for CD15, 22.2% (14/63) for CD34, and 4.7% (3/64) for CD68 (PG-M1). Proliferation index, as demonstrated by Ki-67 positivity, was 0.49+/-0.22. Follow-up data was obtained in 59 of the 82 patients. The two- and five-year survival rates were 36.1% and 17.3% respectively. No significant prognostic factors were found in the survival analysis. CONCLUSIONS: Myeloid sarcoma may precede, develop in a background of myeloproliferative disorder or even after remission of the disease. The presence of immature eosinophils is an important morphologic clue and immunohistochemical study plays an essential role in arriving at a correct diagnosis. Immunopositivity for myeloperoxidase is specific for granulocytic differentiation, while CD68 (PG-M1)-positivity suggests monocytic differentiation. Detailed clinicopathologic correlation is also helpful.