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41.

Background

With the significant growth of migration and expatriation, facilitated by increased global mobility, the number of Koreans living abroad as of 2016 is approximately 7.4 million (15% of the Korean population). Healthcare utilization or health problems, especially among expatriates in developing countries, have not been well researched despite the various health risks these individuals are exposed to. Consequently, we identified the health utilization patterns and healthcare needs among Korean expatriates in Vietnam, Cambodia, and Uzbekistan.

Methods

This cross-sectional survey examined 429 Korean expatriates living in Vietnam (n?=?208), Cambodia (n?=?60), and Uzbekistan (n?=?161) who had access to the Internet and were living abroad for at least 6?months. A 67-item questionnaire was used, and feedback was received via an online survey program. Stepwise logistic regression analyses were performed to evaluate factors associated with unmet healthcare needs and preferences of certain type of telemedicine.

Results

We found that 45.5% (195/429) of respondents had used medical services in their country of stay. Among those who visited health institutions >?3 times, the most popular choice was general hospitals (39.4%, 15/38); however, they initially visited Korean doctors’ or local doctors’ offices. The most essential criteria for healthcare service facilities was a “skilled professional” (39.3%, 169/429), 42% wanted a health program for chronic disease management, and 30% wanted specialized internal medicine. A substantial number wanted to access telemedicine services and were willing to pay for this service. They were particularly interested in experts’ second opinion (61.5%, 264/429) and quick, 24-h medical consultations (60.8%, 261/429). Having unmet healthcare needs and being younger was strongly associated with all types of telemedicine networks.

Conclusions

Nearly half of the expatriates in developing countries had unmet healthcare needs. Telemedicine is one potential solution to meet these needs, especially in developing countries.
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In order to evaluate whether 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] could increase the serum concentration of osteocalcin (BGP) in patients with post-menopausal osteoporosis, we administered 2 micrograms/d of 1,25(OH)2D3 to 14 patients with biopsy proven osteoporosis for two weeks. An additional 13 age and sex-matched patients with osteoporosis received no drug and served as the control. Administration of 1,25(OH)2D3 significantly increased the serum concentration of 1,25(OH)2D from 31 +/- 2 SE to 56 +/- 5 pg/ml (p less than 0.01). Commensurate with the rise in 1,25(OH)2D was a significant increase in BGP from 3.9 +/- 0.6 to 6.4 +/- 0.9 ng/ml (p less than 0.001). There were no significant changes for these parameters in the control group. It is concluded that short term 1,25(OH)2D3 administration is effective in raising BGP concentrations in patients with post-menopausal osteoporosis.  相似文献   
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We conducted Mongolia's first nation-wide cross-sectional survey of sexually transmitted infections (STIs) among pregnant women attending prenatal care. Among our 2000 participants, 386 (19.3%) were infected with Chlamydia trachomatis, 133 (6.7%) with Trichomonas vaginalis, 121 (6.1%) with Neisseria gonorrhoeae, and 128 (6.4%) were seropositive for Treponemal antibodies. None of our participants were seropositive for HIV infection. Additionally, 605 (30.3%) of the women had at least one STI, 133 (6.7%) had a double infection, and 15 (0.8%) had a triple infection. Our results suggest that STIs are a serious problem in Mongolia. Pregnant women represent a lower-risk general population; these high STI rates suggest that at this nascent stage, the identification, treatment, and prevention of STIs as risk factors for HIV transmission are crucial in the prevention of the emerging Mongolian HIV epidemic.  相似文献   
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The effect of hydrochlorothiazide on the formation of renal stones was evaluated by quantitative assessment of the propensity of urine to undergo crystallization of calcium oxalate. In seven patients with calcium urolithiasis (three with absorptive hypercalciuria, one with renal hypercalciuria, and three with normocalciuric nephrolithiasis), the urinary activity product ratio and formation product ratio of calcium oxalate were measured both on and off therapy with hydrochlorothiazide (50 mg orally twice a day). The activity product ratio (state of saturation with respect to calcium oxalate) decreased in the majority of cases, primarily as a result of the fall in urinary calcium. The formation product ratio (limit of metastability) increased in all cases; the cause of the increase was not readily apparent. Both changes reduced the propensity of urine to undergo crystallization of calcium oxalate, and therefore may account for the clinical improvement reported during thiazide therapy in nephrolithiasis.  相似文献   
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The structure-guided design of chloride-conducting channelrhodopsins has illuminated mechanisms underlying ion selectivity of this remarkable family of light-activated ion channels. The first generation of chloride-conducting channelrhodopsins, guided in part by development of a structure-informed electrostatic model for pore selectivity, included both the introduction of amino acids with positively charged side chains into the ion conduction pathway and the removal of residues hypothesized to support negatively charged binding sites for cations. Engineered channels indeed became chloride selective, reversing near −65 mV and enabling a new kind of optogenetic inhibition; however, these first-generation chloride-conducting channels displayed small photocurrents and were not tested for optogenetic inhibition of behavior. Here we report the validation and further development of the channelrhodopsin pore model via crystal structure-guided engineering of next-generation light-activated chloride channels (iC++) and a bistable variant (SwiChR++) with net photocurrents increased more than 15-fold under physiological conditions, reversal potential further decreased by another ∼15 mV, inhibition of spiking faithfully tracking chloride gradients and intrinsic cell properties, strong expression in vivo, and the initial microbial opsin channel-inhibitor–based control of freely moving behavior. We further show that inhibition by light-gated chloride channels is mediated mainly by shunting effects, which exert optogenetic control much more efficiently than the hyperpolarization induced by light-activated chloride pumps. The design and functional features of these next-generation chloride-conducting channelrhodopsins provide both chronic and acute timescale tools for reversible optogenetic inhibition, confirm fundamental predictions of the ion selectivity model, and further elucidate electrostatic and steric structure–function relationships of the light-gated pore.Discovery and engineering of the microbial opsin genes not only has stimulated basic science investigation into the structure–function relationships of proteins involved in light-triggered ion flow but also has opened up opportunities for biological investigation (reviewed in ref. 1) via the technique of optogenetics, which involves targeting these genes and corresponding optical stimuli to control activity within specified types of cells within intact and functioning biological systems. For example, optogenetics has been used to identify causally the brain cells and projections involved in behaviors relevant to memory formation, affective states, and motor function, among many other discoveries (24). For the channelrhodopsins, an important member of this protein family widely used in optogenetics (5, 6), the light-activated cation-conducting channel pore has been the subject of structural investigation, both because of curiosity regarding the physical properties of its ion conduction and because the creation of inhibitory channels had been sought for optogenetic applications. Converging lines of work recently achieved the latter goal; resolving the high-resolution structure of channelrhodopsin (7) allowed a principled structure-guided approach to engineering for chloride selectivity by testing an electrostatic model for pore function (8, 9). Subsequently, by screening the genome of the Guillardia theta microbe, two naturally occurring light-gated chloride-conducting channelrhodopsins (10) were identified.Because optogenetic control of behavior has not yet been demonstrated with chloride channelrhodopsins, and to test further integrative ideas regarding pore function from structural considerations as shown here, we sought to design and test the next generation of enhanced chloride channels (iC++ and SwiChR++). Along the way, we provide the initial test of the hypothesis that light-activated channels will be more efficient tools than pumps for optogenetic neuronal inhibition at the cellular level, demonstrate the initial utility of light-gated chloride channels in controlling behavior in freely moving animals, and reveal key principles regarding the functional selectivity of light-gated ion channel pores.  相似文献   
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An indolent case of severe acute respiratory syndrome   总被引:1,自引:0,他引:1  
Severe acute respiratory syndrome (SARS) is a highly contagious and typically rapidly progressive form of atypical pneumonia, which spread from Asia to many parts of the world in early 2003. Clinical diagnosis of SARS requires the presence of unremitting fever and progressive pneumonia despite antibiotic therapy, particularly in the presence of lymphopenia and raised transaminase levels. We report the case of a woman who had undergone a successful allogeneic bone marrow transplant for acute myeloid leukemia. She presented initially with fever and a normal chest radiograph. Her indolent clinical course of SARS was punctuated by resolution of fever, but there was progressive radiologic deterioration and increasing serum antibody titer against SARS coronavirus. Treatment with oral prednisolone and ribavirin normalized her lymphopenia, altered transaminases, chest radiograph and high-resolution computed tomography appearances rapidly. Our experience should alert other clinicians in recognizing this atypical indolent presentation of SARS, to protect health care workers and the community at large and to ensure that these patients are properly treated.  相似文献   
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