[en] The aminolysis reactions of aryl thionocarbamates (ATNC) with benzylamines in acetonitrile are investigated at 10.0 .deg. C. The rate of ATNC is slower than the corresponding aminolysis of aryl thiocarbamate (ATC), which has been interpreted in terms of cooperative effects of atom pairs O and S on the reactivity and mechanism. For concerted processes, these effects predict a rate sequence, -C(=S)-S- < -C(=S)-O- <-C-(=O)-S- < -C-(=O)-O-, and our results are consistent with this order. The negative cross-interaction constant, ρ_XZ = -0.68, the size of β_Z (= 0.69∼0.88) and failure of the RSP are in accord with the concerted mechanism. The normal kinetic isotope effects, k_H/k_D = 1.55 ∼ 1.74, involving deuterated benzylamines suggest a hydrogen bonded cyclic transition state. In spite of the large amount of research that has been carried out, there are still many facets of the aminolysis of aryl esters, carbonates, carbamates, and their thio analogs, that are not well understood. These include the effects of the nonleaving group R, RO or RNH, and the combined or cooperative effects of the atom pairs, X and X', on the aminolysis reactivity and mechanism of

[en] MgO thin films were deposited with r.f. magnetron sputtering method. Deposition parameters such as working pressure and r.f. power were found to influence properties of deposited films. As working pressure increased, crystallinity deteriorated while rms surface roughness decreased and film density increased. In this case, grain size did not change much compared with the case of r.f. power. On the other hand, as r.f. power increased, both grain size and rms surface roughness increased while film density decreased. An increase of r.f. power improved crystallinity a little and induced (1 0 0) preferred orientation. But the amount of variation was small compared with the case of pressure. Sputtered MgO thin films were hydrated by exposing in the humid ambience with 80% relative humidity at room temperature. Hydration reaction produced clusters, Mg(OH)₂, on the surface of the films. Hydration also occurred in the inner part of MgO thin film. The entire hydrated region was observed to be approximately 2 nm thick. Therefore, the factors that influence hydration seem to be density and grain size of MgO films. MgO film with high density can restrict inter-diffusion of Mg atom and H₂O, which is an important process for hydration. A reduction of grain size increased the area of grain boundary, which provided nucleation sites of hydration reaction as well as the short path of inter-diffusion of Mg atoms and H₂O molecules. From the results, the relation between deposition condition and hydration characteristics of MgO thin films can be established

[en] To evaluate the radioprotective efficacy of candidate compounds, we examined the effects of selenium compounds, melatonin, and propolis on the colony forming efficiency (CFE) of gamma-irradiated CHO cells. - Protective effects of selenium compounds against radiation-induced cytotoxicity Sodium selenite showed protective effects at low concentrations against radiation-induced toxicity in CHO cells, whereas its effects were weak at higher concentrations. Selenomethionine also reduced the radiation-induced cytotoxicity. Both of these compounds showed highest protective effects at the concentration of 1 uM. - Protective effects of melatonin against radiation-induced cytotoxicity Melatonin showed the protective effects against radiation-induced cytotoxicity, and the protection was highest at 1 mM concentration. - Protective effects of selenium compounds against hydrogen peroxide-induced cytotoxicity Propolis showed dose-dependent inhibition of hydrogen peroxide-induced cytotoxicity. In particular, the highest inhibition was observed when propolis were treated at 0.3 and 1 ng/ml 24h prior to the hydrogen peroxide treatment. The protective effects of propolis was observed only when it was pretreated at least 8 hours before hydrogen peroxide treatment

[en] An efficient method of addition of trimethylsilyl cyanide to aldehydes by employing a zirconium complex as the catalyst has been described. A variety of aromatic, aliphatic, cyclic and heterocyclic aldehydes has been converted into corresponding trimethylsilyl ethers in excellent yield within short reaction time

[en] Milk fistula is a tract between the skin and a lactiferous duct that may occur as a complication after core biopsy using a large needle for the diagnosis of the breast lesion during pregnancy or breast feeding, this complication. We report a case of milk fistula developed after a core needle biopsy in lactating breast.

[en] To compare sonography and mammography in terms of their diagnostic value in breast cancer cases which initially presented as an axillary mass without a palpable mass or other clinical symptoms. Seven patients with enlarged axillary lymph nodes who first presented with no evidence of palpable breast lesions and who underwent both mammography and sonography were enrolled in this study. In six of the seven, the presence of metastatic adenocarcinoma was confirmed preoperatively by axillary needle aspiration biopsy; in four, subsequent sonographically guided breast core biopsy performed after careful examination of the primary site indicated that primary breast cancer was present. In each case, the radiologic findings were evaluated by both breast sonography and mammography. Breast lesions were detected mammographically in four of seven cases (57%); in three of the four, the lesion presented as a mass, and in one as microcalcification. In three of these four detected cases, fatty or scattered fibroglandular breast parenchyma was present; in one, the parenchyma was dense. In the three cases in which lesions were not detected, mammography revealed the presence of heterogeneously dense parenchyma. Breast sonography showed that lesions were present in six of seven cases (86%); in the remaining patient, malignant microcalcification was detected at mammography. Final pathologic examination indicated that all breast lesions except one, which was a ductal carcinoma in situ, with microinvasion, were infiltrating ductal carcinomas whose size ranged from microscopic to greater than 3 cm. At the time of this study, all seven patients were alive and well, having been disease free for up to 61 months after surgery. In women with a palpable axillary mass confirmed as metastatic adenocarcinoma, breast sonography may be a valuable adjunct to mammography

[en] We wanted to determine if the analysis and categorization of breast lesions with using BI-RADS for US would be useful. We retrospectively reviewed 1,024 cases (976 persons), in which US-guided core needle biopsy had been performed. The breast lesions were described and categorized according to the BI-RADS for US. Each US characteristic was analyzed in order to determine its association with a benign versus malignant tissue diagnosis. The diagnostic sensitivity, specificity, positive predictive value and negative predictive value, and the accuracy of breast US were examined. Logistic regression analyses of the US features in terms of their ability to distinguish between benign and malignant breast lesions showed that all eight US features (shape, orientation, margin, echogenicity, posterior acoustic features, surrounding tissue, calcification and special cases) were statistically significant. Moreover, the shape, margin, microcalcification and enlarged axillary lymph nodes were found to be the most useful diagnostic features. In addition, a clinically palpable mass increased the diagnostic accuracy up to 92.7%. The positive predictive value of a category 3 lesion was 0.8%, and those of category 4 and 5 lesions were 30.4% and 99.4%, respectively. The diagnostic sensitivity, specificity, positive predictive value, negative predictive value and accuracy of breast US were 99.0%, 57.2%, 49.5%, 99.3% and 69.6%, respectively. Using BI-RADS for US in breast can be successful for characterizing and differentiating both the malignant and benign lesions of the breast

[en] The aims of this study were to make the lung cancer clinics in Korea Cancer Center Hospital, and to establish new therapeutic methods of lung cancer for increasing the cure rate and survival rate of patients. Also another purpose of this study was to establish a common treatment method in our hospital. All patients who were operated in Korea Cancer Center Hospital from 1987 due to lung cancer were followed up and evaluated. And we have been studied the effect of postoperative adjuvant therapy in stage I, II, IIIA non-small cell lung cancer patients from 1989 with the phase three study form. Follow-up examinations were scheduled in these patients and interim analysis was made. Also we have been studied the effect of chemo-therapeutic agents in small cell lung cancer patients from 1997 with the phase two study form. We evaluated the results of this study. Some important results of this study were as follows. 1. The new therapeutic method (surgery + MVP chemotherapy) was superior to the standard therapeutic one in stage I Non-small cell lung cancer patients. So, we have to change the standard method of treatment in stage I NSCLC. 2. Also, this new therapeutic method made a good result in stage II NSCLC patients. And this result was reported in The Annals of Thoracic Surgery. 3. However, this new therapeutic method was not superior to the standard treatment method (surgery only) in stage IIIA NSCLC patients. So, we must develop new chemo-therapeutic agents in the future for advanced NSCLC patients. 4. In the results of the randomized phase II studies about small cell lung cancer, there was no difference in survival between Etoposide + Carboplatin + Ifosfamide + Cisplatin group and Etoposide + Carboplatin + Ifosfamide + Cisplatin + Tamoxifen group in both the limited and extended types of small cell lung cancer patients

[en] Among coordination compounds, chelate d¹⁰ metal complexes are of great interest due to their high thermal stability and low cost as well as their good photoluminescent and electroluminescent properties. For example, Zn(II) complexes with nitrogen and oxygen donor atoms exhibit blue and white emissions. Meanwhile, less luminescent Hg(II) complexes have been reported. Recently some coordination polymeric Hg(II) complexes have shown blue fluorescence originating from intraligand charge transfer (ILCT) transitions. Herein, two novel d¹⁰ metal (M²⁺ = Zn²⁺ and Hg²⁺) complexes with 2-[4-(dimethylamino)styryl] pyridine (dmasp) were prepared and their structural and luminescent properties were investigated. The dmasp ligand was of interest as it had an electron push-pull system, thereby stabilizing the π^* levels and, in them, ILCT transitions could arise readily through a conjugated π system, which is also important to ILCT photo-luminescent materials as well as the second-order nonlinear optical (NLO) materials

[en] The purpose of this study was to identify the characteristics of chest lesions that are missed in interpretations of neck computed tomography (CT) scans. A total of 240 consecutive neck CT scans were retrospectively analyzed to determine whether chest lesions were included or not. All missed chest lesions, which had not been described on neck CT reports, were recorded, and classified according to their clinical significance (insignificant, indeterminate, or significant) and awareness (known or unknown) at the time of CT interpretation, and their radiologic patterns were analyzed. Eighty seven (36.3%) of 240 neck CT scans had 105 chest lesions, and 88 of these were not described on the neck CT reports. Thirty seven clinically known or insignificant lesions were excluded, resulting in a miss rate for chest lesions of 35.2% (37/105), with six of these (5.7%) being potentially significant. The most common location of missed chest lesions was the lung (56/88, 63.6%), and 45 (80.4%) of these missed lung lesions were visualized only with lung window settings. Chest lesions were common and frequently missed on neck CT interpretations. When reviewing neck CT scans, a special attention should be given to lung lesions by using lung window settings