Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 9 de 9
Filter
Add more filters










Database
Publication year range
1.
Org Lett ; 25(23): 4252-4257, 2023 Jun 16.
Article in English | MEDLINE | ID: mdl-37265105

ABSTRACT

An efficient electrochemical dehydrogenative cross-coupling of benzylic C-H bonds with 1-thiosugars at room temperature is described. The direct S-glycosylation protocol avoids using any oxidant, which provides facile access to various glycosylated xanthene derivatives with up to 91% yield. This current electrooxidative reaction is characterized by high atom economy, high efficiency, mild reaction conditions, being environmentally benign, and excellent functional group tolerance. Moreover, preliminary mechanistic investigations reveal that the reaction involves a free radical process.


Subject(s)
Thiosugars , Glycosylation , Drug Tolerance , Oxidants , Xanthenes
2.
Orthop Surg ; 12(5): 1430-1438, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32812708

ABSTRACT

OBJECTIVE: To gain a better understanding of the traumatic mechanism and to develop appropriate treatment for dislocation of the shoulder joint with an ipsilateral humeral shaft fracture. METHODS: This was an observational and descriptive study. Nine patients with traumatic shoulder dislocations associated with ipsilateral humeral shaft fractures who visited the emergency room and received treatment from January 2012 to June 2018 were retrospectively analyzed. CT with three-dimensional reconstruction was performed to provide precise anatomical information of the fractures. The traumatic event and the type of fracture of the humeral shaft were analyzed to help determine the trauma mechanism. Closed reduction of the dislocation was attempted at once under intravenous anesthesia. One patient died the following day due to unrelated causes. All humeral shaft fractures of the eight patients received internal fixation, and then reduction of the dislocation was performed again if previous attempts failed. The affected limb was immobilized in a sling for 3 weeks postoperatively, and then active and passive movement was encouraged. Patients were evaluated based on clinical and radiographic examinations, shoulder joint range of motion, Constant-Murley score, and subjective shoulder value. RESULTS: Four cases in the present study could not give a clear description of the traumatic procedure. The other five patients suffered a second strike on their upper arms when they were hurt, with low mobility and high pain in the shoulder region. Seven cases were simple fractures and two were wedge fractures. According to the AO/OTA classification system, four cases were type 12-A2, three were type 12-A3, and two were type 12-B2. Six patients successfully obtained closed manipulative reduction of the shoulder dislocation in the acute stage. The follow-up time ranged from 18 to 31 months. No deep wound infections were encountered. All fractures healed uneventfully. The union time ranged from 4 to 6 months. At the final follow-up, shoulder range-of-motion values were found to range from 140° to 170° forward flexion, 30° to 40° extension, 40° to 45° adduction, 150° to 170° abduction, 50° to 60° internal rotation, and 50° to 60° external rotation; no recurrent instability of the shoulder joint occurred; the Constant-Murley score was 89.5 ± 3.7 points (range: 84-94 points); the subjective shoulder value was 89.4% ± 6.3% (range: 75%-95%). CONCLUSION: Shoulder dislocation most likely occurs first with an axial force or a direct posteroanterior force and a subsequent force results in the shaft fracture. For patients with mid-distal humerus fractures, closed manipulative reduction of the joint is usually effective. After success of closed reduction, surgery for the humeral shaft fracture is advocated to ensure stability and to make patient nursing convenient. In cases with fractures in the proximal third of the humeral shaft, fixation is suggested beforehand to help reduce the shoulder dislocation.


Subject(s)
Fracture Fixation, Internal/methods , Humeral Fractures/surgery , Shoulder Dislocation/surgery , Accidental Falls , Accidents, Traffic , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Humeral Fractures/classification , Male , Middle Aged , Retrospective Studies , Young Adult
3.
Huan Jing Ke Xue ; 34(9): 3352-7, 2013 Sep.
Article in Chinese | MEDLINE | ID: mdl-24288975

ABSTRACT

The observation was conducted in Mangdang Mountain, Nanping, Fujian Province in the spring of 2009. Ozone, HONO, HCHO and H2O2 which are regarded as the sources of .OH and other atmospheric components were measured. Mixing ratios of O3, HCHO, HONO and H2O2 were determined to be 4.96 x 10(-8), 3.97 x 10(-10), 2. 53 x 10(-10) and 1.18 x 10(10) respectively, which were lower than the previous observation at the rural areas in Northern China. Using CMAQ, the contribution factors to the .OH of O3, HCHO, HONO, and H2O2 were calculated to be 57.0%, 7.7%, 34.9% and 0.4% respectively. The photolysis of O3 was the most important source of OH radicals in the atmosphere. The contribution factors of O3, HCHO, and H2O2 had a single peak during 12:00-13:00 local time. For HONO, the contribution factor showed fluctuations during the daytime, unlike the human living environment in which it peaked in the morning.


Subject(s)
Air Pollutants/analysis , Environmental Monitoring , Hydrogen Peroxide/analysis , Ozone/analysis , Seasons , Atmosphere , China , Photolysis , Reactive Oxygen Species/analysis
4.
Huan Jing Ke Xue ; 31(8): 1762-7, 2010 Aug.
Article in Chinese | MEDLINE | ID: mdl-21090290

ABSTRACT

Through 2,4-dinitrophenylhydrazine (DNPH) high-performance liquid chromatography (HPLC) method, the levels of formaldehyde in ambient air, rain and fog samples were measured in Mangdang Mountain, Fujian Province, from March to April 2009. The average concentrations of formaldehyde in ambient air, rain and fog are 4.0 x 10(-10), 2.19 micromol/L and 2.94 micromol/L, respectively. Based on previous researches, this study described formaldehyde hydrolysis and reacting with S(IV) and other chemical reaction processes in liquid phase, explaining the phenomenon that the solubility of formaldehyde in the liquid phase is higher than the theoretical value. On-site measured Henry coefficients (Hme) and the effective Henry coefficients (H*) were derived from concentration of formaldehyde in ambient air, rain and fog samples and references. Comparing Hme and H*, this study found that the measured liquid phase concentrations of formaldehyde are higher than the theoretical concentrations, consistent with the references. The further founding is that Hme/H* in fog is higher than in rain, proving the result of Mangdang Mountain that the concentration of formaldehyde in fog is higher than in rain. Considering the climatic characteristics of Mangdang Mountain in spring, the wet deposition of formaldehyde is an important way in this area.


Subject(s)
Air Pollutants/analysis , Environmental Monitoring , Formaldehyde/analysis , Rain/chemistry , Weather , Atmosphere/analysis , China , Chromatography, High Pressure Liquid/methods
5.
Zhonghua Yi Xue Za Zhi ; 90(1): 61-3, 2010 Jan 05.
Article in Chinese | MEDLINE | ID: mdl-20356529

ABSTRACT

OBJECTIVE: To study the expression of NASP in platinum resistance ovarian cancer cell clones (C0C1/DDP). METHODS: The proteins of C0C1 and C0C1/DDP were separated by highly sensitive two-dimensional differential gel electrophoresis (2-D DIGE) coupled with matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF-MS) to identify the proteins differentially expressed in cisplatin sensitive and cisplatin resistance cell lines. RESULTS: The investigators found a group of the distinct expressed proteins between C0C1 and C0C1/DDP. Among them, NASP was one of the down-regulated proteins by 21% (Student's t-test; P = 0.01). CONCLUSION: The identification of NASP in C0C1/DDP has laid a foundation for future in-depth researches into the mechanisms of ovarian cancer platinum resistance.


Subject(s)
Autoantigens/metabolism , Cisplatin/pharmacology , Drug Resistance, Neoplasm , Nuclear Proteins/metabolism , Ovarian Neoplasms/metabolism , Cell Line, Tumor , Cisplatin/therapeutic use , Electrophoresis, Gel, Two-Dimensional , Female , Humans , Neoplasm Proteins/metabolism , Ovarian Neoplasms/drug therapy
7.
Fa Yi Xue Za Zhi ; 24(2): 118-21, 2008 Apr.
Article in Chinese | MEDLINE | ID: mdl-18605042

ABSTRACT

OBJECTIVE: By measuring lengths of tibias and fibulas in computed radiography (CR) of living body, regression formulae for stature estimation were obtained from these measurements that were adapted to the population of northern adults of Han. METHODS: The length of tibias and fibulas were measured in radiography, including 422 subjects (207 men and 215 women). The body height of each subject was also recorded. Linear regression analysis between body height and the length of tibias and fibulas , analysis of variance of hypothesis test of linear regression model and t-test of the partial regression coefficient were applied to establish the regression equations for stature estimation. Then the paired t-test between the predictive value and the actual body height, the residual analysis, the tests of equal scedasticity and colinearity had been done to evaluate whether the equations accord with the model. RESULTS: Thirty five regression equations which were statistical significant were obtained. The multiple correlation coefficient was from 0.909 to 0.823 and the standard error of the estimation was between 2.48-3.87 cm. CONCLUSION: The lengths of tibias and fibulas on the CR films could be helpful to estimate stature. These equations could be used to estimate the body height of the Han population in North China.


Subject(s)
Body Height , Fibula/diagnostic imaging , Forensic Anthropology/methods , Tibia/diagnostic imaging , Tomography, X-Ray Computed , Adult , China/ethnology , Female , Fibula/anatomy & histology , Humans , Linear Models , Male , Middle Aged , Radiographic Image Interpretation, Computer-Assisted , Tibia/anatomy & histology
8.
J Environ Sci (China) ; 20(1): 28-32, 2008.
Article in English | MEDLINE | ID: mdl-18572518

ABSTRACT

The hydroxyl radical (*OH) plays a central role in the oxidation and removal of many atmospheric compounds. Measurement of atmospheric *OH is very difficult because of its high reactivity and low atmospheric abundance. In this article, a simple and highly sensitive method, high performance liquid chromatography coupled with coulometric detection (HPLC-CD), was developed to determine *OH indirectly by determining its reaction products with salicylic acid (SAL), 2,3-dihydroxybenzoic acid (2,3-DHBA), and 2,5-dihydroxybenzoic acid (2,5-DHBA). Under the optimum conditions for its determination, 2,3-DHBA and 2,5-DHBA could be well separated and the detection limits for 2,3-DHBA were 3 x 10(-10) mol/L and for 2,5-DHBA were 1.5 x 10(-10) mol/L, which were lower than most previous reports. This method was also applied to measure atmospheric hydroxyl radical levels and demonstrated the feasibility in clean and polluted air.


Subject(s)
Air Pollutants/analysis , Hydroxyl Radical/analysis , China , Chromatography, High Pressure Liquid/methods , Electrochemistry , Environmental Monitoring
9.
Huan Jing Ke Xue ; 25(4): 28-31, 2004 Jul.
Article in Chinese | MEDLINE | ID: mdl-15515931

ABSTRACT

Simultaneous measurements of atmospheric hydroxyl radicals (OH) and other pollutants in Guangzhou city were carried out in July, 2000. The quantitative analysis of HOx reaction cycle during daytime in summer was made. The calculation results indicated that the total production rates of OH and HO2 were about 4.5 x 10(8) OH/(cm3 x s) and 3.8 x 10(8) HO2/(cm3 x s), respectively. The primary OH source in urban atmosphere was the photolysis of HONO, while the main OH sinks were the reactions of OH with VOCs, HCHO, NO2 and CO. The HOx chemistry in urban atmosphere is quite different from that in the remote clean atmosphere.


Subject(s)
Air Pollutants/analysis , Environmental Monitoring/statistics & numerical data , Hydroxides/chemistry , Hydroxyl Radical/chemistry , China , Cities , Hydroxyl Radical/analysis , Photochemistry , Seasons
SELECTION OF CITATIONS
SEARCH DETAIL
...