• Journal of Nutrition and Health
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• v.29 no.5
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• pp.461-471
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• 1996

This study was performed to investigate the effect of dietary protein and cysteine levels on cadmium toxicity in rats. Seventy-two male rats of Sprague-Dawley strain weighting 171$\pm$3g were blocked into 12 groups according to body weight, and were raised for 30 days. cadmium chloride was given at levels of 0 or 400ppm, protein at levels of 7, 15 and 40%, and cysteine was added(total dietary cysteine contents : 0.45%) to diet or not. The results are summarized as follow. Food intake, weight gain, food were lower than those of cadmium free group. But, these were increased with increasing dietary protein level and cysteine addition. Fecal cadmium excretion was remarkably increased in high protein (40%) groups. Thus, cadmium retention rates were decreased in high protein groups. Metallothionein concentrations in liver and kidney were increased in cysteine addition, and cadmium administration. Especially, these were remarkably increased in cadmium and cysteine added groups. Urinary calcium excretion was increased with cadmium administration, but urinary protein excretion and creatinine clearance were not changed in these animal. In conclusion, food intake, weight gain and organ weights were decreased with administration. Cadmium toxicity was alleviated by increasing fecal cadmium excretion, while cysteine addition increased metallothionein concentrations in liver and kidney. From these results, it was shown that cadmium toxicity was alliviated by synergistic effect of high protein level and cysteine addition.

• Clinical and Experimental Pediatrics
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• v.48 no.5
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• pp.476-480
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• 2005

Immunosuppressive therapy in pediatric renal transplant recipients is changing consequence of the increasing number of available immunosuppressive agents. The optimal use of immunosuppressive agents requires a thorough understanding of the pharmacokinetic characteristics, but the information on the pharmacokinetic characteristics of these drugs in pediatric transplant recipients is still limited. In general, patients younger than 5 years old show higher clearance rates, therefore the need for higher dosages in younger patients seems evident. By the therapeutic drug monitoring, trough($C_{min}$) and peak level($C_{max}$) are measured and the area under the blood concentration-time curve(AUC), which is taken as being representative of total systemic exposure can be calculated. Cyclosporine A (CSA) has poor bioavailability, which contributes to high inter- and intra-patient pharmacokinetic variability. CSA concentration measured 2 hours after administration($C_2$) has better correlation with the AUC than $C_{min}$ and is an alternative technique that predicts the AUC. Tacrolimus(Tac) has a great deal of inter-individual variability like CSA but intra-individual variability in systemic exposure is considered to be low. Both CSA and Tac are metabolized by a cytochrome P-450 enzyme isoform(CYP3A4). We should consider changing the dosages when CSA or Tac is used in combination with the medicines that inhibit or induce the CYP3A4. In case of steroid-free immunosuppressive therapy, the blood concentration of Tac should be frequently checked and dosage adjustment may be needed.

• Korean Journal of Bronchoesophagology
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• v.9 no.1
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• pp.30-38
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• 2003

Cancers of the cervical esophagus occur uncommonly, but treatment is remaining a challenging problem and surgery demands special knowledge of abdominal, thoracic, and neck surgery. The primary risk factor is chronic heartburn, leading to a sequence of esophagitis, Barrett's esophagus, reflux esophagitis and etc. Among the various treatment modalities, Surgery is still a mainstay of treatment. The main aim of surgery is not only oncologically adequate resection but also preservation or restoration of physiologic functions, such as deglutition and phonation. Surgical treatment of cervical esophageal cancer is influenced by special problems arising from tumor factors, patient factors and surgeon factors. Complete clearance of loco-regional disease and prevention of postoperative complications are of particular importance for the improvement of long-term survival in patients with these cancers. So the cervical and thoracic extension of these tumors usually required an extensive lymphadenectomy with primary resection. Radical resection of the primary site almostly include sacrifice of the larynx, but the voice could be rehabilitated with various methods, such as tracheoesophageal prosthesis or tracheoesophageal shunts, etc. Restoration of the esophageal conduit can be performed using gastric or colon interposition, radial forearm free flap or jejunum free flap, etc. Recently, the advances of radiation therapy and chemotherapy will enable less extended resections with greater rates of laryngeal preservation. At initial presentation, up to 50％ to 70％ of patients will have advanced locoregional or distant disease with virtually no chance for cure. Patients with advanced but potentially resectable esophageal cancer are generally treated by surgery with some form of neoadjuvant chemotherapy, radiotherapy, or both, with 5-year survivals in the 20％ to 30％ range. So the significant adverse factors affecting survival should be taken into account to select the candidates for surgery.

• International Journal of Air-Conditioning and Refrigeration
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• v.11 no.3
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• pp.132-139
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• 2003

The effects of casing shapes on the performance and the interaction between an impeller and a casing in a small-sized centrifugal compressor are investigated. Especially, numerical analyses are conducted for the centrifugal compressor with both a circular casing and a volute one. The optimum design for each element (i.e., impeller, diffuser and casing) is important to develop an efficient and compact compressor using alternative refrigerant as working fluids. Typical rotating speed of the compressor is in the range of 40,000∼45,000 rpm. The impeller has backswept blades due to tip clearance and a vane diffuser has wedge type. In order to predict the flow pattern inside an entire impeller, vaneless diffuser and casing, calculations with multiple frames of reference method between the rotating and stationery parts of the domain are carried out. For computations of compressible turbulent flow fields, the continuity and time-averaged Navier-Stokes equations are employed. To evaluate the performance of two types of casings, the static pressure recovery and loss coefficients are obtained for various flow rates. Also, static pressure distributions around casings are studied for different casing shapes, which are very important to predict the distribution of radial load. The static pressure around the casing and pressure difference between the inlet and outlet of the compressor are measured for the circular casing.

• Biomolecules & Therapeutics
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• v.4 no.1
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• pp.7-18
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• 1996

5-Hydroxytryptamine(5-HT, serotonin), when given into the vein, produced antidiuretic action accompanied with reduction of glomerular filtration(GFR), renal plasma flow(RPF), osmolar clearance(Cosm) and amounts of sodium or potassium excreted in urine( $E_{Na}$ , $E_{K}$), with the augmented reabsorption rates of sodium and potassium in renal tubules. 5-HT, when infused into a renal artery, exhibited diuretic action accompanied with the augmented RPF and increased $E_{Na}$ and $E_{K}$ in only infused kidney. Antidiuretic action of 5-HT infused into the vein was not influenced by ketanserin, 5-H $T_2$receptor blockade, given into a renal artery, vein or carotid artery, by methysergide, 5-H $T_1$receptor blockade, given into a renal artery, whereas above antidiuretic action was inhibited by methysergide given into vein or carotid artery. Diuretic action of 5-HT infused into a renal artery in only experimental kidney was blocked by ketanserin injected into a renal artery, was not influenced by methysergide administered into a renal artery. Above results suggest that 5-hydroxytryptamine(5-HT) produced the antidiuretic action through central 5-H $T_1$receptor and the diuretic action through 5-H $T_2$receptor located in renal tubules of kidney.ney.

• The Journal of Advanced Prosthodontics
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• v.12 no.1
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• pp.38-48
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• 2020

PURPOSE. The objective of this literature review was to analyze the cumulative survival rates (CSRs) of rigid and non-rigid double-crown-retained removable dental prostheses. MATERIALS AND METHODS. Screening of the literature published from January 1995 to December 2019 was performed by using electronic data base (Pubmed) and manual search. The CSRs of rigid and non-rigid double crown removable dental prostheses were investigated. RESULTS. A total of 403 articles were reviewed and 56 relevant articles of them were selected. Subsequently, 25 articles were included for data extraction. These articles were classified according to rigid and non-rigid type double crowns and further subdivided into teeth, implants, and teeth-implant combination types. The CSRs of rigid type double crown ranged from 68.9% to 95.1% of 5 to 10 years in tooth abutments, 94.02% to 100% over a 3-year mean observation periods in implant abutments, and 81.8% to 97.6% in tooth-implant combination. Non-rigid type double crowns had various CSR ranges from 34% to 94% maximum during 10 years observation in teeth abutment. The CSRs of non-rigid type had over 98% in implant abutments, and ranged from 85% to 100% in tooth-implant combination. CONCLUSION. The CSRs of double crowns varies according to types. With accurate evaluation of the remaining teeth and plan of the strategic implant placement, it could be successful treatment alternatives for partially or completely edentulous patients.

• The KSFM Journal of Fluid Machinery
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• v.9 no.1 s.34
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• pp.9-18
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• 2006

In the range of very low specific speed ($n_s<0.25$, non-dimensional), the performance of a centrifugal pump is much different from that of a centrifugal pump of normal ns and the efficiency of the pump drops rapidly with the decrease of $n_s$. In order to examine the reason of unstable performance characteristics of the very low $n_s$- centrifugal pump, the internal flow of the pump with a semi-open impeller is measured by a PTV(Particle Tracking Velocimetry) system. The purpose of this study is to make clear the internal flow characteristics and to obtain basic knowledge of the pump performance. The results show that the leakage flow through tip clearance give a strong effect on the flow pattern of impeller passage. A large vortex in the impeller passage and a strong reverse flow at impeller outlet are formed in the range of small flow rates, and the vortex and the reverse flow together reduce the absolute tangential velocity at the impeller outlet and cause the performance instability.

• YAKHAK HOEJI
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• v.27 no.4
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• pp.271-282
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• 1983

This study is an attempt to study the influence of clonidine, which has a central sympatholytic action, on the renal function in dogs and to elucidate its mechanism of action. Clonidine ($15\mu$g/kg) injected into a cephalic vein of the dog produced a marked increase in urine flow and in amounts of $Na^{+}$ and $K^{+}$ excreted in urine, and clearances of free water and osmolar substance, the reabsorption rates of $Na^{+}$ and $K^{+}$ in renal tubules were significantly decreased. Clonidine ($50.0]mu$g/kg) administered intravenouly elicited a transient reduction in urine flow, along with inhibition of all renal functions. Intravenous clonidine-induced diuretic effect was completely blocked by pretreatment with reserpine, and was lessened by water diuresis. Clonidine ($3.0\mu$g/kg) injected tnto a carotid artery revealed a transient diuresis with a increase in clearance of free water. Clonidine injected into a renal artery showed a significant antidiuretic effect and all functions of an experimental kidney were reduced. Antidiuretic action induced by clonidine given into a renal artery markedly suppressed by pretreatment with reserpine. The above results suggest that clonidine has dual mechanisms: 1) diuretic effect due to the central sympatholytic action and inhibition of release of antidiuretic hormone, and 2) antidiutetic effect indued by indirect symptheic stimulation in the periphery.

• Journal of Ginseng Research
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• v.44 no.2
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• pp.194-204
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• 2020

The detrimental impact of air pollution as a result of frequent exposure to fine particles posed a global public health risk mainly to the pulmonary disorders in pediatric and geriatric population. Here, we reviewed the current literature regarding the role of ginseng and/or its components as antimicrobials, especially against pathogens that cause respiratory infections in animal and in vitro models. Some of the possible mechanisms for ginseng-mediated viral inhibition suggested are improvements in systemic and mucosa-specific antibody responses, serum hemagglutinin inhibition, lymphocyte proliferation, cell survival rate, and viral clearance in the lungs. In addition, ginseng reduces the expression levels of proinflammatory cytokines (IFN-γ, TNF-α, IL-2, IL-4, IL-5, IL-6, IL-8) and chemokines produced by airway epithelial cells and macrophages, thus preventing weight loss. In case of bacterial infections, ginseng acts by alleviating inflammatory cytokine production, increasing survival rates, and activating phagocytes and natural killer cells. In addition, ginseng inhibits biofilm formation and induces the dispersion and dissolution of mature biofilms. Most clinical trials revealed that ginseng, at various dosages, is a safe and effective method of seasonal prophylaxis, relieving the symptoms and reducing the risk and duration of colds and flu. Taken together, these findings support the efficacy of ginseng as a therapeutic and prophylactic agent for respiratory infections.

• The KSFM Journal of Fluid Machinery
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• v.18 no.1
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• pp.37-43
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• 2015

A Beta-type Stirling engine is developed and tested on the operation stability and cycle performance. The flow rate for cooling water ranges from 300 to 1500 ml/min, while the temperature of heat source changes from 300 to $500^{\circ}C$. The internal pressure, working temperatures, and operation speed are measured and the engine performance is estimated from them. In the experiment, the rise in the temperature of heat source reduces internal pressure but increases operation speed, and overall, enhances the power output. The faster coolant flow rate contributes to the high temperature limit for stable operation, the cycle efficiency due to the alleviated thermal expansion of power piston, and the heat input to the engine, respectively. The experimental Stirling engine showed the maximum power output of 12.1 W and the cycle efficiency of 3.0 % when the cooling flow is 900 ml/min and the heat source temperature is $500^{\circ}C$.