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991.
The applicability of ultra-high performance liquid chromatography (UHPLC) for real-time analysis of a synthetic process was examined. A reduction reaction was selected as a model process. Quantities of acetophenone (AcPh) and phenyl ethanol (PhEt) in reaction solutions were analyzed at 5- and 15-min intervals. Reaction solutions were diluted using acetonitrile and subsequently filtered. A mixture of acetonitrile and water (6:4) was used as the mobile phase. PhEt and AcPh were detected at 0.64 and 0.75 min, respectively. Additionally, as many as nine different impurities were detected in the reaction solution. Given the ability to detect impurities in a reaction solution within a few minutes, UHPLC technology is deemed applicable for real-time synthetic process control.  相似文献   
992.
We present a rare case of 26-year-old male patient without a history of epilepsy, who underwent a voice monitoring surgery under local anesthesia plus sedation using modified neuroleptanalgesia. As he developed generalized tonic-clonic seizure probably due to pentazocine, the operation was cancelled. Later, the same surgery was rescheduled. After a premedication with intramuscular phenobarbital, the patient was sedated with dexmedetomidine and locally anesthetized, showing sedation of high quality with no respiratory depression and no seizure. Dexmedetomidine was used succesfully for voice monitoring surgery.  相似文献   
993.
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995.
BACKGROUND AND AIM: Transpapillary bile duct brushing cytology and/or forceps biopsy was performed in the presence of an indwelling guidewire in patients with biliary stricture, and the treatment time, overall diagnosis rate, diagnosis rate of each disease, complications, and influences on subsequent biliary drainage were investigated. METHODS: After endoscopic retrograde cholangiography, brushing cytology was performed, followed by forceps biopsy. In patients with obstructive jaundice, endoscopic biliary drainage (EBD) was subsequently performed. To investigate the influences of bile duct brushing cytology and forceps biopsy on EBD, patients who underwent subsequent EBD by plastic stent were compared with patients who underwent EBD alone. RESULTS: The samples for cytology were collected successfully in all cases, and the sensitivity for malignancy/benignity, specificity, and accuracy were 71.6%, 100%, and 75.0%, respectively. The biopsy sampling was successful in 51 patients, and samples applicable to the evaluation were collected in all 51 patients. The sensitivity for malignancy/benignity, specificity, and accuracy were 65.2%, 100%, and 68.6%, respectively. Combination of the two procedures increased the sensitivity and accuracy to 73.5% and 76.6%, respectively. The time required for cytology and biopsy was 11.7 min, which is relatively short. Cytology and biopsy did not affect drainage. Regarding accidents, bile duct perforation occurred during biopsy in one patient (1.9%), but was rapidly improved by endoscopic biliary drainage. CONCLUSIONS: Transpapillary brushing cytology and forceps biopsy could be performed in a short time. The diagnosis rate was high, and the incidence of complication was low, having no influence on subsequent biliary drainage.  相似文献   
996.
Purpose SMARCB1/INI1, which negatively regulates cell cycle progression from G0/G1 into the S-phase via the p16INK4a-RB-E2F pathway, has been reported to be inactivated homozygously by deletion and/or mutations in malignant rhabdoid tumor (MRT). In the current study, we investigated the alteration of the SMARCB1/INI1 gene using simple methods, and its gene product at the protein level. Moreover, we investigated the status of hyperphosphorylation in RB protein, known as a key cell cycle molecule. Methods Three cell lines and 11 formalin-fixed, paraffin-embedded specimens of MRT were investigated. SMARCB1/INI1 gene alteration was analyzed with simple methods as a quantitative real-time PCR and direct sequencing method. Furthermore, SMARCB1/INI1 and RB protein were immunohistochemically evaluated. Results In 12 of 14 cases, we detected genetic alterations comprised of nine (including three cell lines) homozygous deletions and three mutations, which can induce abnormal expression of gene products. At the protein level, SMARCB1/INI1 immunohistochemical expressions were not detected in any cases. Twelve out of 14 cases showed high-level (+5) expression of tRB (both hyperphosphorylated and underphosphorylated RB), combined with low-level (+1) expression of uRB (underphosphorylated RB), indicating a high rate of hyperphosphorylation. Conclusions We could analyze the SMARCB1/INI1 gene alteration with simple methods, and SMARCB1/INI1 gene alteration was found in 12 of 14 cases. Especially, quantitative real-time PCR was a convenient and accurate method. In addition, a high rate of hyperphosphorylation of RB gene was recognized. These results suggest that the clinically aggressive character of MRT is caused by the inactivation of the SMARCB1/INI1 gene.  相似文献   
997.
Anti-hypertensive agents with antioxidative effects are potentially useful for diabetic patients with hypertension to prevent the onset and progression of their complication. While dihydropyridine-type calcium antagonists are among the frequently used anti-hypertensive drugs, azelnidipine, a novel calcium antagonist, has been reported to have a unique anti-oxidative effect in vitro and in animals. In this study, we measured lipid hydroperoxides in human sample using diphenyl-1-pyrenylphosphine for the first time, and used the value of lipid hydroperoxides as an index of oxidative stress. Then, we compared the antioxidative properties of azelnidipine and amlodipine, a frequently used calcium antagonist in hypertensive diabetic patients. Administration of vitamin C and E for 8 weeks significantly reduced lipid hydroperoxides in erythrocyte membrane in normal subjects. In hypertensive diabetic patients, azelnidipine treatment for 12 weeks induced a more significant fall in erythrocyte lipid hydroperoxide level than amlodipine, though blood pressure during each treatment was comparable. Our data confirm the usefulness of lipid hydroperoxides in erythrocyte membrane as a marker of oxidative stress in vivo, and indicate that azelnidipine has a unique antioxidative property in human.  相似文献   
998.
Gefitinib is an inhibitor of the tyrosine kinase activity of epidermal growth factor receptor (EGFR). Accumulating evidence suggests that gefitinib may provide a survival benefit to EGFR mutation-positive non-small lung cancer patients. We have established a clinical test that can detect EGFR mutations from cytological specimens or paraffin-embedded tissue specimens that are contaminated by normal cells. This test is based on the peptide nucleic acid, locked nucleic acid polymerase chain reaction clamp method that can detect G719S, G719C, L858R, L861Q and seven different exon 19 deletions in the presence of 100-1000-fold wild-type alleles. Consequently, using a small aliquot of samples isolated to establish a cancer diagnosis, the EGFR mutation status is determined soon after the diagnosis of cancer is made. We investigated the EGFR mutation status in 86 patients using a variety of cytological specimens (59 bronchoscopy specimens, 16 pleural effusion, 9 sputum, and 2 pericardial effusion) and in 46 patients who had a disease relapse and paraffin-embedded tissues were available. Forty-five patients (34%) were positive for mutation (29 exon 19 deletions, 16 L858R and 1 L861Q). The sensitivity and the specificity of this test was 97% and 100%, respectively. EGFR mutation status thereby obtained was used to determine each patient's therapeutic regimen. This test is easily integrated into the normal clinical practice for lung cancer, while allowing the medical staff to select therapeutic regimen depending on the EGFR mutation status.  相似文献   
999.
Cytokines produced by tumor cells may have various effects on antitumor immune responses and tumor growth. In the present study, the cytokine production of 31 lung cancer cell lines was evaluated, while any correlation with the histological type, the induction of tumor-specific cytotoxic T lymphocytes (CTL) in vitro, and angiogenesis and the infiltration of inflammatory cells in tumor tissues were also examined. Production of interleukin (IL)-1alpha, IL-1beta, IL-4, IL-6, IL-8, IL-10, tumor necrosis factor (TNF)-alpha, granulocyte macrophage colony stimulating factor (GM-CSF), granulocyte colony stimulating factor, transforming growth factor (TGF)-beta and vascular endothelial growth factor (VEGF) in the culture supernatant was measured using enzyme-linked immunosorbent assay. Each cytokine was produced in a substantial number of the tumor cell lines. In particular, IL-6, IL-8, TGF-beta and VEGF were produced in 18 (55%), 29 (94%), 31 (100%) and 28 (90%) of 31 cell lines, respectively. However, neither IL-4 nor TNF-alpha was produced at all by any tumor cell line. TGF-beta production was significantly higher in adenocarcinoma than in squamous cell carcinoma (P = 0.03). Immunohistochemical staining revealed the magnitude of macrophage infiltration, and angiogenesis in surgically resected tumor tissue specimens correlated well with GM-CSF and IL-8 production from the corresponding cell lines. Among six lung cancer cell lines, CTL were induced in the three lung cancer cell lines that produced a lower amount of TGF-beta (<100 pg/mL). These findings suggested that TGF-beta produced by tumor cells could inhibit the induction of CTL in vitro. The present results suggest that the production of various cytokines from tumor cells might exert various paracrine effects both in vivo and in vitro.  相似文献   
1000.

Purpose

Pediatric surgeons require highly advanced skills when performing endoscopic surgery, but their experience with such cases tend to be limited in comparison to general surgeons. The aim of this study was to evaluate the effectiveness of basic endoscopic surgery training for less-experienced young pediatric surgeons and then compare their skills with those of general surgeons.

Methods

The surgeons (n = 477) subjected to this study underwent a 2-day endoscopic skill training program, consisting of lectures, box training, VR simulator training, tissue training, and live tissue training. The trainees were divided into two groups: P (pediatric surgeons, n = 33) and G (general surgeons, n = 444). The trainees were required to make a continuous suture along a circle measuring 2.5 cm in diameter and the findings were evaluated both before and after training. A statistical analysis was conducted using the unpaired t test.

Results

The number of experienced cases totaled 20.8 ± 23.9 in P and 60.6 ± 80.5 in G (p < 0.001). The number of completed sutures before training was 1.4 ± 1.1 in P and 1.9 ± 1.5 in G (p < 0.05). The number of completed sutures after training was 4.1 ± 1.3 in P and 3.9 ± 1.9 in G (p > 0.05). The economy and speed of the forceps improved, however, the number of errors increased.

Conclusion

Less-experienced pediatric surgeons improved their surgical skill and ability until reaching almost the same level as that observed in more experienced general surgeons during training, however, the number of errors after training increased in comparison to before training. As a result, this program needs to be modified to reduce the number of errors while enabling pediatric surgeons to master the safe and precise surgical techniques needed in this field.  相似文献   
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