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1.
J Nanosci Nanotechnol ; 12(1): 84-90, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22523949

RESUMO

Single walled carbon nanotubes (SWCNTs) were dispersed in water and attached to nylon fabrics by a dip-drying procedure; scanning electron microscopy and Raman spectroscopy suggest the attachment of the SWCNTs. The electrical resistance of the functionalized fabrics is found to be pH-dependent, which is correlated with the quantity of SWCNTs dispersed in water at different values of pH. This can be further ascribed to the influence of the pK(a) of the acid (e.g., acetic acid in this study) used to tune pH. The acid may affect the dispersion of SWCNTs through two different mechanisms: (1) the free protons may protonate the amine and/or sulfonate group in the dye molecules, resulting in a variety of interactions among the dye molecules, SWCNTs and water molecules and (2) the resulting ions may increase the ionic strength of the solution, compressing the electric double layers of SWCNT colloids and thus impairing their stability. The former possibility is ruled out by data obtained using X-ray photoelectron spectroscopy, Raman spectroscopy, and ultraviolet-visible-near infrared spectroscopy; thus the latter is proposed to account for the experimental results. The colour strength of the functionalized fabrics increases with increasing pH, which is in agreement with their measured electrical properties.


Assuntos
Cristalização/métodos , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Nylons/química , Têxteis , Absorção , Impedância Elétrica , Concentração de Íons de Hidrogênio , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
2.
Phys Rev Lett ; 102(4): 046804, 2009 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-19257457

RESUMO

The excitement of nano-test-tube chemistry in a single-walled carbon nanotube is exemplified in our study on electron doping in carbon nanotubes. Electron doping through the 1D van Hove singularity of single-walled carbon nanotubes is realized via a chemical reaction of an encapsulated organocerium compound, CeCp3. The decomposition of CeCp3 inside the carbon nanotubes increases the doping level and greatly enhances the density of conduction electrons. The transition of the cerium encapsulating semiconducting tubes to metallic results in enhanced screening of the photoexcited core hole potential. This fact illustrates the importance of many body effects in understanding core-level excitation process in carbon nanotubes.

3.
Phys Rev Lett ; 100(3): 037601, 2008 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-18233036

RESUMO

The full three-dimensional dispersion of the pi bands, Fermi velocities, and effective masses are measured with angle-resolved photoemission spectroscopy and compared to first-principles calculations. The band structure by density-functional theory underestimates the slope of the bands and the trigonal warping effect. Including electron-electron correlation on the level of the GW approximation, however, yields remarkable improvement in the vicinity of the Fermi level. This demonstrates the breakdown of the independent electron picture in semimetallic graphite and points toward a pronounced role of electron correlation for the interpretation of transport experiments and double-resonant Raman scattering for a wide range of carbon based materials.

4.
Kyobu Geka ; 54(4): 293-7, 2001 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-11296420

RESUMO

BACKGROUND: The off-Pump coronary artery bypass (OPCAB) has recently gained popularity. However the safety and feasibility of the procedure has not been fully proven especially for unstable myocardial ischemia. METHODS: Between March 1998 and November 2000, 135 patients with a mean age of 69.7 (41-95) underwent off-pump coronary artery bypass via sternotomy. Eight patients were operated on emergently and 11 were urgently. LV function ranged from 8% to 70%. Eleven patients required preoperative IABP. RESULTS: All procedures were completed without conversion to cardiopulmonary bypass. The mean number of grafts per patient was 2.8 (range, 1 to 6). Cardiac-related hospital mortality was 2.2% (3/135). Angiographic assessment of grafts demonstrated an overall patency of 98.0%, arterial grafts 98.7% and venous grafts 96.6%. In retrospect, these were equivalent results of conventional coronary artery bypass by the same operator. CONCLUSION: OPCAB is safe and feasible even with LV dysfunction or unstable myocardial ischemia.


Assuntos
Ponte de Artéria Coronária/métodos , Doença das Coronárias/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Ponte de Artéria Coronária/estatística & dados numéricos , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/estatística & dados numéricos
5.
Int J Urol ; 8(3): 99-105, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11260333

RESUMO

OBJECTIVES: Transurethral needle ablation of the prostate is a new alternative endoscopic thermal therapy that uses a low-energy radio frequency delivered into the prostatic adenoma. Herein is reported the initial clinical experience by multiple institutes in Japan of transurethral needle ablation of the prostate for the treatment of symptomatic benign prostatic hyperplasia. METHODS: A total of 93 patients were treated with this technique. Transurethral needle ablation of the prostate was generally performed under low-spinal anesthesia. Before and after the procedure, international symptom score (IPSS), quality of life (QOL) score, peak urinary flow rate (Qmax), postvoid residual urine volume and prostate size were evaluated. RESULTS: There was a reduction of IPSS of more than 50% when compared with that of pretreatment, being 51.3% (57/93 patients) and 60.2% (56/93 patients) at 3 months and 6 months after the procedure, respectively. Sixty-seven patients who were available for a 12-month follow-up period demonstrated a markedly decreased mean IPSS when compared with that measured before the treatment for a statistically significant difference (P < 0.01). Fifty-eight patients who were available for uroflowmetric study at 12 months exhibited a notably increased mean Qmax of 11.2 +/- 4.5 mL/s, which was a statistically significant increase when compared with that found before treatment (P < 0.05). Although all patients suffered some degree of gross hematuria after the procedure, none of them required any specific treatment for complications. CONCLUSION: Transurethral needle ablation technique for the treatment of symptomatic benign prostatic hyperplasia is safe and effective. However, a much longer follow-up study is essential for fully evaluating the extended effectiveness of this technique.


Assuntos
Ablação por Cateter , Hiperplasia Prostática/cirurgia , Idoso , Idoso de 80 Anos ou mais , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Agulhas , Hiperplasia Prostática/complicações , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/fisiopatologia , Qualidade de Vida , Uretra , Urodinâmica
6.
Int J Urol ; 6(7): 341-5, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10445303

RESUMO

BACKGROUND: We evaluated the efficacy and safety of transurethral needle ablation (TUNA) of the prostate for treatment of symptomatic benign prostatic hyperplasia (BPH) as one institute participating in a Japanese clinical trial. METHODS: Thirty-three patients with symptomatic BPH were treated with the TUNA procedure in our institute. The international prostate symptom score (IPSS), quality of life (QOL) score, residual urine volume (RV), prostate volume (PV) and peak urinary flow rates (Qmax) were measured and complications were assessed. RESULTS: We followed and evaluated 30 of the 33 cases. At 12 months there were significant improvements in the IPSS (20.7 to 11.2, P < 0.0001), QOL score (4.9 to 2.1, P < 0.0001), RV (46.6 to 22.6 mL, P < 0.01), PV (37.8 to 30.0 mL3, P < 0.002) and Qmax (8.00 to 11.0 mL/s, P < 0.002). There were no serious complications. CONCLUSION: This trial shows that the TUNA procedure is a safe and efficacious treatment for symptomatic BPH.


Assuntos
Hipertermia Induzida/métodos , Hiperplasia Prostática/terapia , Idoso , Idoso de 80 Anos ou mais , Biópsia , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Agulhas , Hiperplasia Prostática/patologia , Segurança , Resultado do Tratamento , Uretra , Cateterismo Urinário
7.
Hinyokika Kiyo ; 45(2): 111-3, 1999 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-10212784

RESUMO

Three cases of transitional cell carcinoma (TCC) in the urinary bladder diverticulum were encountered during a period of 12 years and bladder preserving treatments were performed. Case 1: A 78-year-old man was admitted with a chief complaint of hematuria. Papillary tumors in the diverticulum of the right bladder wall were revealed (TCC, G3, T3N0M0). Intraarterial infusion chemotherapy was performed and complete remission was achieved. When a recurrent bladder tumor appeared 22 months later, transurethral resection was performed and there was no evidence of recurrence for 50 months. Case 2: A 60-year-old man was admitted with a chief complaint of gross hematuria. Cystoscopic examination revealed papillary tumors in a bladder diverticulum near the ureteral left orifice. Transurethral resection revealed TCC G2 and carcinoma in situ. Partial cystectomy, including the bladder diverticulum, and vesicoureteral neostomy was performed. The histological stage of the tumor was pTis and the wall of diverticulum possessed a thin muscle layer histopathologically. Twenty two months later, recurrence in the left bladder wall developed and transurethral resection and bladder instillation therapy were performed. For 21 months he had no evidence of recurrence. Case 3: A 59-year-old man was admitted with a chief complaint of hematuria. A solid tumor in the diverticulum of the bladder left wall was revealed. After 4 courses of intraarterial infusion chemotherapy, 41% remission was achieved and partial cystectomy was performed. Histopathological diagnosis was TCC G3, pT3b, INF-alpha, v (-), ly (-), and no muscle layer was found in the diverticulum. There was no evidence of recurrence 16 months after operation. By using the combination therapy, bladder preserving treatment is possible in the cases of bladder cancer arising in the diverticulum.


Assuntos
Carcinoma de Células de Transição/patologia , Divertículo/patologia , Doenças da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/patologia , Idoso , Carcinoma de Células de Transição/etiologia , Divertículo/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Doenças da Bexiga Urinária/complicações , Neoplasias da Bexiga Urinária/etiologia
8.
J Pharm Sci ; 87(1): 96-100, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9452976

RESUMO

Indeloxazine hydrochloride (IDX), a cerebral activator, has a bitter astringent taste. To prepare powders of IDX without this bitter taste, microparticles (median diameter, 130 microns) of IDX were coated with a mixture comprising hydrogenated oil and surfactants in a fluidized bed using the side-spray method. Drug release from the resulting coated particles was significantly delayed. Dissolution rate was remarkably enhanced, however, by heat-treating the coated particles at a temperature above the melting point of the surfactant in the coated layer. The results of differential scanning calorimetry measurements show that part of the surfactant in the coated layer exists separately. Further, surface changes in the coated layer before and after heat treatment showed that this enhancement of dissolution rate was due to rediffusion of the surfactant in the coated layer followed by melting of the surfactant. This effect allows the design of powders of IDX which release the drug quickly and with bioequivalence to the commercial IDX 20 mg tablets while sufficiently suppressing the bitter taste.


Assuntos
Antidepressivos/química , Morfolinas/química , Paladar , Antidepressivos/administração & dosagem , Antidepressivos/farmacocinética , Disponibilidade Biológica , Estudos Cross-Over , Composição de Medicamentos , Temperatura Alta , Humanos , Masculino , Microscopia Eletrônica de Varredura , Morfolinas/administração & dosagem , Morfolinas/farmacocinética , Poloxaleno , Pós , Solubilidade
9.
J Synchrotron Radiat ; 5(Pt 3): 808-10, 1998 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-15263660

RESUMO

This article describes the successful design and fabrication of, and metrological results from, an elastically bent parabolic mirror. The mirror is equipped with a bending structure that allows the mirror to be bent meridionally to a parabolic shape. This bent parabolic mirror is the key component of the extremely high-quality monochromators designed for the SPring-8 figure-8 soft X-ray undulator and the 2.0 GeV high-brilliance synchrotron radiation source (VSX).

11.
Int J Urol ; 4(3): 311-3, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9255674

RESUMO

A right nephrectomy was performed on a 51 year-old female with a tumor surrounding the right kidney since the possibility of malignant lymphoma could not be excluded based on radiography or a needle biopsy. An immunohistological examination of the surgically-resected specimen confirmed a diagnosis of pseudolymphoma. A pseudolymphoma involving the urinary tract is rare, and this is only the second reported case of pseudolymphoma in the perirenal space.


Assuntos
Nefropatias/diagnóstico por imagem , Pseudolinfoma/diagnóstico por imagem , Feminino , Humanos , Nefropatias/patologia , Nefropatias/cirurgia , Pessoa de Meia-Idade , Nefrectomia , Pseudolinfoma/patologia , Pseudolinfoma/cirurgia , Tomografia Computadorizada por Raios X
14.
Nihon Hinyokika Gakkai Zasshi ; 86(5): 996-9, 1995 May.
Artigo em Japonês | MEDLINE | ID: mdl-7596086

RESUMO

Laparoscopic nephrectomy has been performed widely for minimally invasive therapy. However, the procedure of insertion of needles and trocars can cause vascular and intestinal injuries. In addition, pneumoperitoneum using high pressure CO2 gas can cause circulatory and respiratory problems. In order to avoid these problems, we tried retroperitoneoscopic nephrectomy without CO2 gas in 8 kidneys of 4 pigs. A 1.5 cm skin incision was made just below the lowest rib and a small retroperitoneal space was made with the forefinger. The sheath of a 27 Fr rigid nephroscope was covered with a condom balloon and inserted into the retroperitoneal space. Under observing through the nephroscope, the condom was filled with 150-200 ml saline to make a space for the operation. After removing the nephroscope with condom, a scope and trocars were inserted into the space and retroperitoneoscopic nephrectomy was performed. Making the space with condom balloon in the retroperitoneal space was very efficient. The procedures succeeded in 8 and average procedure time was 3 hours. Retroperitoneoscopic nephrectomy without gas is a very attractive minimally invasive technique.


Assuntos
Laparoscopia , Nefrectomia/métodos , Pneumoperitônio Artificial , Animais , Feminino , Laparoscópios , Masculino , Suínos
15.
Diagn Ther Endosc ; 2(1): 29-33, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-18493378

RESUMO

The gold standard of surgical treatment for superficial bladder tumor is transurethral resection (TUR). However, the procedure has drawbacks: it needs skill to avoid perforation of the bladder wall, while burns on the resected tissue are disadvantageous for histological examination. We developed an endoscopic ultrasonic aspiration system which is easy to manipulate and makes no burns on aspirated tissue. Furthermore, the equipment includes a coagulating system.Transurethral ultrasonic aspiration was performed in 19 cases of superficial bladder tumor with a prototype 24Fr Y-shaped rigid endoscope. The efficacy of bladder tumor aspiration was evaluated and ultrasonic aspiration was compared to the conventional TUR procedure. Bladder tumors less than 2 cm were aspirated very rapidly. Blood loss was minimal and the largest tumor aspirated in this series weighed 6.5 grams. Aspirated tissue was large enough for histological examination. Compared to conventional TUR, the ultrasonic aspiration has advantages of no burns on aspirated tissue and easy manipulation. Transurethral ultrasonic aspiration may be an alternative procedure for the treatment of superficial bladder tumor.

16.
Hinyokika Kiyo ; 40(12): 1093-5, 1994 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-7863861

RESUMO

A 27-year-old female complained of right upper abdominal pain. Computed tomography revealed a retroperitoneal tumor located between the right kidney and the vena cava. The preoperative value of noradrenaline in urine was high, 221.1 micrograms/day. She underwent surgery and the resected tumor was 330 g in weight and 8 x 6 x 4 cm in size. Histopathological diagnosis was ganglioneuroma. Retroperitoneal ganglioneuroma is rare and only 82 cases including our case have been reported in Japan, in recent years, adult cases are increasing in number. Endocrinological abnormalities were observed in 9 cases. Although six of the 9 patients were younger than 5 years old, the others were adults. These adult patients had no endocrinological symptoms.


Assuntos
Ganglioneuroma/sangue , Norepinefrina/sangue , Neoplasias Retroperitoneais/sangue , Adulto , Feminino , Humanos , Norepinefrina/urina
17.
Hinyokika Kiyo ; 40(11): 1027-32, 1994 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-7832076

RESUMO

During the last 8 years, 70 cases of testicular tumor were treated in our department. Of them 2 cases had brain metastasis. Case 1; A 37-year-old male was admitted with the chief complaint of cough. Retroperitoneal lymph node and lung metastases were discovered (stage IIIB, pT4aN1M1). Resected right testis was diagnosed as embryonal carcinoma, teratoma and STGC histopathologically. After 3 courses of PVB (cisplatinum, vincristine, bleomycin) chemotherapy right hemiplegia occurred and computerized tomographic (CT) scan revealed brain metastasis. His general condition degraded rapidly and he died of brain herniation 3 months after orchiectomy. Case 2; A 32-year-old male was admitted because of right testicular swelling and lung metastases (stage IIIB, pTiN0M1). Pathological examination revealed embryonal carcinoma, yolk sac tumor and teratoma. After 4 courses of chemotherapy with cisplatinum (CDDP), vincristine, methotrexate, peplomycin, and etoposide all lung metastases were disappeared. A few months later left hemiplegia by brain metastasis appeared suddenly. Four additional courses of high dose chemotherapy and resection of brain metastasis was performed. Complete remission continued for 13 months. The prognosis of testicular tumor with brain metastasis was very poor. During the last 8 years, 21 cases of testicular tumor with brain metastasis were reported in the Japanese literature. A follow-up study of prognosis in the literature was performed and discussed.


Assuntos
Neoplasias Encefálicas/secundário , Neoplasias Testiculares/patologia , Adulto , Carcinoma Embrionário/secundário , Tumor do Seio Endodérmico/secundário , Humanos , Neoplasias Pulmonares/secundário , Masculino , Prognóstico , Teratoma/secundário
18.
J Endourol ; 8(4): 285-6, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7526930

RESUMO

The authors have developed an ultrasonic aspirator to assist in urologic endoscopic surgery. It appeared that ultrasonic aspiration of bladder tumors was clinically efficient in transurethral surgery. Tumors 1 to 2 cm in diameter could be aspirated completely with this instrument alone. The application of the ultrasonic aspirator, which has also been designed with a coagulating function, to laparoscopic lymphadenectomy was evaluated. A special probe sheath was used to insulate it when using coagulation current. During operation, perivascular fatty tissue was removed safely with the aspirator. In the near future, the ultrasonic aspirator will be one of the most effective tools in laparoscopic surgery.


Assuntos
Endoscopia , Hiperplasia Prostática/cirurgia , Sucção/instrumentação , Ultrassom , Neoplasias da Bexiga Urinária/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Instrumentos Cirúrgicos
20.
Biosci Biotechnol Biochem ; 58(5): 921-5, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-7764979

RESUMO

S-Glycoproteins have been thought to play a role in the self-incompatibility in Brassica plants. Two cDNAs encoding S-glycoproteins were isolated from stigmas of two strains of Brassica campestris. Their amino acid sequences are highly homologous to each other. However, the numbers of the potential glycosylation sites are different, although most of them are conserved. In the middle part of the sequences, there are two supervariable regions which might contribute to the specificity of each S-glycoprotein. Genomic Southern analysis showed many bands hybridizing with cDNA of S-glycoproteins in various Brassica species including self-compatible species.


Assuntos
Brassica/genética , Glicoproteínas/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Sequência de Bases , Biotecnologia , Brassica/classificação , DNA Complementar/genética , Genes de Plantas , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
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