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1.
In this review, we have discussed recent developments on the direct selenosulfonylation of unsaturated compounds which lead to the formation of two new carbon-sulfur and carbon-selenium bonds in a single operation. The reactions were classified based on the type of starting unsaturated compound and product. Thus, the review is divided into three major sections. The first describes the current literature on selenosulfonylation of alkenes. The second section covers the available literature on selenosulfonylation of alkynes. The third focuses exclusively on selenosulfonylation of allenes.

In this review, we have discussed recent developments on the direct selenosulfonylation of unsaturated compounds which lead to the formation of two new carbon-sulfur and carbon-selenium bonds in a single operation.  相似文献   
2.
CD34+ progenitor cells can harbour latent human cytomegalovirus (HCMV); however, the mechanisms of HCMV latency remain unclear. We have investigated the effects of the haematopoietic lineage restriction on the establishment and spread of the latent HCMV to progeny cells. In vitro-infected and latently-infected haematopoietic progenitor cells derived from HCMV seropositive donors were studied. The presence of HCMV DNA in bone marrow progenitor (BMP) cells was determined by single colony polymerase chain reaction and fluorescent in situ hybridization (FISH). The presence of CMV DNA was found to be restricted to myeloid progenitors and the percentage of HCMV-infected cells was lower in naturally-infected cells than in in vitro-infected cells. Erythroid differentiation resulted in an abortive infection with persistence of the viral nucleic acids in red cell precursors. In BMP cells from HCMV seronegative donors, HCMV DNA was localized in the nucleus. Bone marrow progenitors in the presence of granulocyte-macrophage colony stimulating factor (GMCSF) maintained HCMV DNA for extended periods of time. No viral production could be detected throughout the culture but the comparison of the numbers of latently-infected cells prior to and after the culture suggests that proliferation of haematopoietic progenitor cells may lead to the expansion of latently-infected cells.  相似文献   
3.
Phosphorus-containing compounds are one of the most important classes of organic compounds, which have wide applications in organic chemistry, medicinal chemistry, agricultural chemistry, and materials chemistry. In particular, organophosphorus compounds bearing a P(O)–C bond have attracted significant attention in recent decades due to their widespread biological and pharmacological activities. In this review, we will highlight the most important developments in the construction of P(O)–C bonds through decarboxylative C–P cross-coupling reactions. The literature has been surveyed from 2011 to May 2018.

Phosphorus-containing compounds are one of the most important classes of organic compounds, which have wide applications in organic chemistry, medicinal chemistry, agricultural chemistry, and materials chemistry.  相似文献   
4.
Evidence for a Physiologic Role of Erythropoietin in Fetal Erythropoiesis   总被引:4,自引:0,他引:4  
Administration of antibody prepared inrabbits against human urinary Ep to fetalsheep during the last third of the gestation period resulted in a suppression oferythropoiesis in the fetus. This wasevidenced by a sharp decrease in the numbers of circulating reticulocytes and a reduced rate of 59Fe incorporation into RBC,spleen, and bone marrow, effects ascribable to a neutralization of endogenous Ep.In addition, there was a significant decrease in the numbers of nucleated erythroid cells in the bone marrows of thesefetuses. These results point to a physiologic role for Ep in fetal erythropoiesis.

Submitted on December 17, 1973 Revised on February 19, 1974 Accepted on February 20, 1974  相似文献   
5.
A method was developed for the quantitative separation of platelets from CF1mouse whole blood. This made it possibleto determine the platelet incorporation of35S-sulfate without the necessity of doingplatelet counts. Daily hypertransfusions ofthe mice to three to four times normalplatelet levels for 4-5 days significantlyreduced platelet uptake of radiosulfate toan average of about 40% of the nontransfused controls. Mice rendered thrombocytopenic 48 hr earlier by antiplateletserum, had 2-day 35S uptakes over 2 1/2times the controls and 6 times the hypertransfused animals. The administration of atotal of 2 ml of serum, given twice daily for3 days from a thrombocytopenic patientwith Hodgkin's disease caused a highlysignificant 103% rise in radiosulfate incorporation when compared with saline in thehypertransfused mouse. Normal humanserum from a healthy donor caused a smalland insignificant rise. The serum from a patient with Hodgkin's disease caused ahighly significant 63% rise in 35S incorporation when compared to the normal serum.

Submitted on June 19, 1972 Revised on March 10, 1973 Accepted on March 10, 1973  相似文献   
6.
In our previous studies, we showed that frontal lobe and brainstem functions were abnormal in online game addicts. In this study, 14 students with Internet addiction disorder and 14 matched healthy controls underwent proton-magnetic resonance spectroscopy to measure cerebral function. Results demonstrated that the ratio of N-acetylaspartate to creatine decreased, but the ratio of cho- line-containing compounds to creatine increased in the bilateral frontal lobe white matter in people with Internet addiction disorder. However, these ratios were mostly unaltered in the brainstem, suggesting that frontal lobe function decreases in people with Internet addiction disorder.  相似文献   
7.
Correction for ‘Oxidative carboxylation of olefins with CO2: environmentally benign access to five-membered cyclic carbonates’ by Liang Wang et al., RSC Adv., 2020, 10, 9103–9115.

The Royal Society of Chemistry regrets that incorrect details were given for Ref. 10b, 11b and 11c in the original article. The correct versions of Ref. 10b, 11b and 11c are given below as Ref. 1, 2a and 2b, respectively.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.  相似文献   
8.
Silver nanoparticles were successfully fabricated through a very simple, rapid, one-step photo-induced green approach. The formation of silver nanoparticles was accomplished using the bioactive compounds in the aqueous extract of fresh Oscillatoria limnetica biomass, which acted as a reducing and capping agent at the same time. The biosynthesis of Oscillatoria-silver nanoparticles (O-AgNPs) was investigated under the influence of different light intensities 57.75, 75.90 and 1276.51 μmol m−2 s−1 (bright sunlight). UV-Vis (UV) and Fourier transform infrared (FT-IR) spectroscopy were applied to approve the synthesis of AgNPs. Further, the synthesis process under the exposure to sunlight was adjusted via utilizing one factor at a time, and 0.5 mM AgNO3 concentration, 5 mL O. limnetica solution, pH 6.7 and 30 min sunlight (1276.51 μmol m−2 s−1) were applied. Furthermore, the central composite design (CCD) was applied to boost the biosynthesis process of O-AgNPs (manufactured at light intensity 75.90 μmol m−2 s−1). The maximum production of O-AgNPs was attained with 4 detected variables: initial pH level (6.7), AgNO3 concentration (0.3 mM), O. limnetica extract concentration (3.50 mL) and incubation time (48 h). Moreover, TEM, in addition to SEM, images exposed that the biosynthesized AgNPs were quasi-spherical in shape with a small monodisperse nature, and the size range was between 6.98–23.48 nm in the case of light-induced synthesis (75.90 μmol m−2 s−1) and 11.58–22.31 nm with sunlight (1276.51 μmol m−2 s−1).

Silver nanoparticles were successfully fabricated through a very simple, rapid, one-step photo-induced green approach.  相似文献   
9.
OBJECTIVE: This study compares telephone consultations with the results of clinical examinations to assess the value and accuracy of telephone consultations for the future planning in a breast cancer clinic in Tehran, Iran. METHODS: In 2500 telephone calls, 800 Symptomatic patients were identified and asked to visit the center for the further investigations by the specialists. The agreement between two observers data were compared by the kappa statistic. RESULTS: Totally 174 patients complied with the recommendation and included in the study. The most common chief complaints of visitors were: breast mass (42%) and breast pain (35%). Kappa statistic showed a very good agreement (K=0.62, P<0.001) between consultants' diagnosis and the specialists findings. This agreement for breast cancer diagnosis, although lower, was also good (K=0.55, P<0.001). CONCLUSION: The study findings indicate that consultants may diagnose and manage some common conditions via telephone, usually following the established protocols. More studies are needed to determine the economic and logistic advantages of telephone consultations. PRACTICE IMPLICATIONS: By assessment of strength and weakness of this service, it is possible to develop an easy to use information system for women who need breast care.  相似文献   
10.
Purpose To examine construct and concurrent validity of the Readiness for Return-To-Work (RRTW) Scale with injured workers participating in an outpatient occupational rehabilitation program. Methods Lost-time claimants (n?=?389) with sub-acute or chronic musculoskeletal disorders completed the RRTW Scale on their first day of their occupational rehabilitation program. Statistical analysis included exploratory and confirmatory factor analyses of the readiness items, reliability analyses, and correlation with related scales and questionnaires. Results For claimants in the non-job attached/not working group (n?=?165), three factors were found (1) Contemplation (2) Prepared for Action-Self-evaluative and (3) Prepared for Action-Behavioural. The precontemplation stage was not identified within this sample of injured workers. For claimants who were job attached/working group in some capacity (n?=?224), two factors were identified (1) Uncertain Maintenance and (2) Proactive Maintenance. Expected relationships and statistically significant differences were found among the identified Return-To-Work (RTW) readiness factors and related constructs of pain, physical and mental health and RTW expectations. Conclusion Construct and concurrent validity of the RRTW Scale were supported in this study. The results of this study indicate the construct of readiness for RTW can vary by disability duration and occupational category. Physical health appears to be a significant barrier to RRTW for the job attached/working group while mental health significantly compromises RRTW with the non-job attached/not working group.  相似文献   
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