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排序方式: 共有6597条查询结果,搜索用时 31 毫秒
101.
Watanuki S Fujiwara T Ishii K Miyake M Itoh M Kitamura K 《Kaku igaku. The Japanese journal of nuclear medicine》2000,37(1):35-41
We measured the resolution and count recovery coefficients (RC) of the SET-2400W whole-body PET scanner (Shimadzu Co., Japan) in the 2D and 3D clinical modes. METHOD: The 3D images were reconstructed by using the full 3D image reconstruction method (3-D reprojection algorithm: 3DRP) and the Fourier rebinning method (FORE). The 2D images were reconstructed with conventional filtered back-projection method (FBP). The measurements of resolution and recovery coefficient were according to JRIA (Japan Radioisotope Association) protocols. RESULTS: The transaxial resolutions of all methods were better than 7 mm FWHM at a radius of 10 cm with 1.25 cm-1 cutoff frequency. The average slice width of 2D FBP, 3DRP and FORE are 5.8 mm, 8.0 mm and 6.8 mm respectively at the center of transaxial field of view. The RC values were measured in a range from 10 mm to 27 mm at 6 cm from the center with the cylindrical and spherical hot area phantoms. In all methods, RC values at 27 mm diameter were nearly 1.0 in both type of hot area. RC values at 10 mm diameter in 2D FBP, 3DRP and FORE of cylindrical hot area were 0.69, 0.72, 0.73 and those of spherical hot area were 0.52, 0.51, 0.53 respectively. CONCLUSION: At the SET-2400W, resolution and recovery coefficient of 3D mode image under the clinical mode showed the value which did not differ from the 2D mode image. 相似文献
102.
Three rare cases of purely intraventricular aneurysms are described, including a unique aneurysm in the fourth ventricle. A 30-year-old female, a 47-year-old male, and an 11-year-old girl presented with disturbance of consciousness due to massive intraventricular hemorrhage. Digital subtraction angiography revealed an idiopathic peripheral aneurysm in the fourth ventricle in the first patient, and aneurysms in the lateral ventricle associated with moyamoya disease in the latter two patients. The former two aneurysms were treated surgically and histologically confirmed to be pseudoaneurysms. The latter aneurysm disappeared spontaneously within 2 months after onset. The aneurysm in the lateral ventricle was resected via a parietal corticotomy with stereotactic insertion of an 8-Fr silicone tube to guide the approach route. This method was very useful because computerized neuronavigation was not available. The aneurysm in the fourth ventricle was resected via a midline suboccipital approach with C-1 laminectomy. Conservative treatment is usually recommended initially for patients with intraventricular aneurysm because spontaneous cure often occurs. We recommend direct surgery if the size of the aneurysm remains unchanged, because the risk of surgery has decreased recently owing to new techniques for neuronavigation. 相似文献
103.
Revisions were made to our new brain retractor with respect as follows. A knob was added to each shaft of the new brain retractor to facilitate handling. The angle between the shaft and the blade can now be adjusted from 60 to 135 degrees, which is useful in deep, narrow operative fields. Three blade lengths (20, 30, and 40 mm) are now available. The new retractor is entirely made from titanium. This revised brain retractor is very useful for the dissection of sylvian and interhemispheric arachnoid membranes, as well as in the extirpation of intracerebral masses via corticotomy. 相似文献
104.
BACKGROUND: Paclitaxel has been difficult to evaluate in preclinical tumor model systems because its poor solubility requires a Cremophor EL formulation, which results in lethal anaphylaxis. We tested the effectiveness of a novel polymeric micellar paclitaxel on androgen-independent tumor growth in the LNCaP tumor model. METHODS: Athymic male mice bearing LNCaP tumors were castrated and allowed to grow until their PSA levels increased to three times above precastration levels. The animals were then treated with 0.5 mg intravenous polymeric micellar paclitaxel once daily for the first 5 days of a 3-week cycle. In total, three cycles were given. Tumor volume and serum PSA levels were measured weekly to monitor tumor progression. RESULTS: In vitro mitogenic assays demonstrated that polymeric micellar paclitaxel was effective in inhibiting LNCaP cell growth with an IC(50) of 5 nM. Paclitaxel precipitated apoptosis in vitro at a concentration of 1 nm and higher, confirmed by DNA laddering. Western blotting demonstrated that paclitaxel treatment phosphorylated and inactivated Bcl-2. In mice bearing LNCaP tumors treated with micellar paclitaxel, tumors regressed rapidly with the commencement of micellar paclitaxel treatment. Tumor size decreased 91% and PSA level decreased 96% after three cycles of treatment. TUNEL immunostaining of the tumor treated with micellar paclitaxel showed marked apoptosis when compared with the control. No significant side effects or mortality was observed in the micellar paclitaxel group (n = 7). In contrast, all (n = 7) mice treated with conventional Cremophor EL paclitaxel died within 1 day of injection. CONCLUSIONS: The polymeric micellar paclitaxel formulation is water-soluble and capable of inducing complete response in mice bearing androgen-independent LNCaP tumors. The lack of toxicity of polymeric micellar paclitaxel permits in vivo preclinical testing of paclitaxel-based combination regimens. 相似文献
105.
106.
To investigate the functional involvement of the pineal gland in circadian expression of the rat period homolog gene (rPer2) in the suprachiasmatic nucleus (SCN) and peripheral tissues, we performed Northern blot analysis in tissues from pinealectomized rats. The ectomy did not have any significant effects on rPer2 mRNA expression patterns both in a daily light-dark condition and in a constant darkness. These results suggest that the rhythmic secretion of pineal melatonin is not essential for the circadian expression of clock genes in the SCN and other peripheral tissues of rats. 相似文献
107.
Toshiharu Miyake Tohru Shinohara Yoshihide Nakamura Tsuyoshi Fukuda Hiroshi Tasato Keiko Toyohara Yuko Tanihira 《Pediatrics international》2004,46(2):135-140
BACKGROUND: This study evaluates the incidence and timing of spontaneous closure (SC) of ventricular septal defect (VSD) using Doppler color flow mapping. METHODS: A total of 225 infants (mean age 30 days) were diagnosed with uncomplicated VSD: 31 (14%) subpulmonary VSD, 159 (70%) perimembranous, and 35 (16%) muscular. The patients were divided into two groups according to the presence or absence of congestive heart failure (CHF). SC was confirmed with color Doppler. RESULTS: Surgical closure was performed in 59 patients (26%). SC occurred in 107 patients (48%); three (10%) of 31 with subpulmonary VSD, 75 (47%) of 159 with perimembranous VSD, and 29 (83%) of 35 with a muscular VSD. Average age at SC was 19 months. In three SC patients with a subpulmonary VSD, there was no aortic valve prolapse and no aortic regurgitation. SC occurred in 96% of SC patients with a perimembranous VSD by the age of 6 years, and in 93% of those with a muscular VSD by the age of 3 years. In patients without CHF, the rate of SC was 72%; 23% in subpulmonary VSD, 74% in perimembranous, and 85% in muscular. SC occurred in only 23% of patients with a perimembranous VSD with CHF. Mean age at the final examination was 6.9 years in 59 patients with a VSD remaining open, and 63% of patients with a perimembranous VSD remaining open had an aneurysm of the ventricular membranous septum. CONCLUSIONS: The SC rate of VSD by mean age of 6.9 years was 48%, but it was 72% in patients without CHF. In patients with CHF, SC was seen only in patients with a perimembranous VSD. The rate of SC was 10% in subpulmonary VSD. The authors contend that SC probably occurred by growth of muscular septum surrounding VSD. Muscular VSD spontaneously closed earlier than perimembranous VSD. 相似文献
108.
Suzuki Kohta Kasai Tsuyoshi Suzuki Mariko Miyake Maki Fujie Michiko Mizuno Kaoruko Hirata Shuji Hoshi Kazuhiko 《Reproductive Medicine and Biology》2004,3(1):27-31
Background : In the summer of 2002, standard guidelines for the application of assisted reproductive technology were reported by a research group of the Ministry of Health, Labor and Welfare. The present study aimed to examine the relationship between the number of cycles of artificial insemination and the cumulative pregnancy rates according to the cause of infertility.
Methods : Patients who experienced their first cycle of artificial insemination during the period of January 1999–December 2002 were included in the study and were divided into a male factor infertility group and an idiopathic infertility group. Cumulative pregnancy rates resulting from artificial insemination with the husband's semen were calculated by the life-table approach.
Results : During the study period, 139 couples entered the assisted reproduction program and underwent 581 cycles. Significant differences were observed in cumulative pregnancy rates between the two groups.
Conclusion : It is recommended that couples with male factor infertility and who fail to conceive within six or seven cycles of intrauterine insemination, consider a modification of treatment strategy such as in vitro fertilization, because cumulative pregnancy rates of this group were reached at a plateau within six or seven cycles. In contrast, patients with idiopathic infertility, the cumulative pregnancy rates appeared to increase constantly with each subsequent cycle. It is important to consider modifications of treatment strategy in the light of the cause of infertility. (Reprod Med Biol 2004; 3 : 27–31) 相似文献
Methods : Patients who experienced their first cycle of artificial insemination during the period of January 1999–December 2002 were included in the study and were divided into a male factor infertility group and an idiopathic infertility group. Cumulative pregnancy rates resulting from artificial insemination with the husband's semen were calculated by the life-table approach.
Results : During the study period, 139 couples entered the assisted reproduction program and underwent 581 cycles. Significant differences were observed in cumulative pregnancy rates between the two groups.
Conclusion : It is recommended that couples with male factor infertility and who fail to conceive within six or seven cycles of intrauterine insemination, consider a modification of treatment strategy such as in vitro fertilization, because cumulative pregnancy rates of this group were reached at a plateau within six or seven cycles. In contrast, patients with idiopathic infertility, the cumulative pregnancy rates appeared to increase constantly with each subsequent cycle. It is important to consider modifications of treatment strategy in the light of the cause of infertility. (Reprod Med Biol 2004; 3 : 27–31) 相似文献
109.
Shin Kariya Mitsuhiro Okano Hisashi Hattori Yuji Sugata Rie Matsumoto Kunihiro Fukushima Patricia A Schachern Sebahattin Cureoglu Michael M Paparella Kazunori Nishizaki 《Otology & neurotology》2006,27(8):1089-1093
OBJECTIVE: Otitis media with effusion is one of the most common and intractable ear diseases. However, the role of Th1, Th2, and immunoregulatory cytokines on the pathogenesis of the disease in adult patients remains to be determined. The aim of this study is to disclose the cytokine expression in middle ear effusions (MEEs) in adults and to compare the profile on the basis of the presence of allergic rhinitis and the type of effusions. STUDY DESIGN: A prospective controlled clinical study. PATIENTS: MEEs were collected from 80 adult subjects. The concentration of interleukin (IL)-2, IL-4, IL-5, IL-10, IL-12, and interferon (IFN)-gamma in MEEs were determined by using enzyme-linked immunosorbent assay. RESULTS: IL-2, IL-4, IL-5, IL-10, IL-12, and IFN-gamma in MEEs were detected in 60 (75.0%), 33 (41.3%), 42 (52.5%), 14 (17.5%), 80 (100%), and 66 (82.5%) samples, respectively. Among these cytokines, only the concentration of IL-4 in the allergic rhinitis-positive group was significantly higher than that in the allergic rhinitis-negative group. On the other hand, IL-2, IL-12, and IFN-gamma were detected, regardless of the presence of allergic rhinitis, and the concentration of these cytokines correlated with each other. The correlation between the concentration of IL-4 and IL-5 was also detected. In addition, both the incidence rate and the concentration of IL-10 in MEEs were significantly higher in the mucoid type compared with those in the serous type effusions. CONCLUSION: Regardless of allergic status, IL-12 may play a critical role in the pathogenesis of otitis media with effusion by affecting the production of IL-2 and IFN-gamma. In addition, IL-4 may have some impact on the immunologic condition in adults with allergic rhinitis. IL-10 potentially affects the viscosity of MEEs. 相似文献
110.
Intermittent antegrade warm blood cardioplegia for CABG: extended interval of cardioplegia 总被引:3,自引:0,他引:3
Minatoya K Okabayashi H Shimada I Tanabe A Nishina T Nandate K Kunihiro M 《The Annals of thoracic surgery》2000,69(1):74-76
BACKGROUND: Intermittent delivery of warm cardioplegia provides a bloodless surgical field, but it is clinically important to evaluate the periods of normothermic ischemia. The aims of this study are to compare intermittent antegrade warm blood cardioplegia (IAWBC) with intermittent antegrade cold blood cardioplegia (IACBC) groups in terms of myocardial protection, and also to evaluate whether the length of ischemic time in the IAWBC group has an effect on myocardial dysfunction. METHODS: This study is based on a retrospective review of patients who underwent elective coronary artery bypass surgery: 162 consecutive patients with IAWBC and 107 consecutive patients with IACBC. RESULTS: The creatinine kinase peak was smaller in the IAWBC group compared with the IACBC group (p<0.0001). The cardiac index after cardiopulmonary bypass was higher in the IAWBC group (p<0.02), and the amount of inotropic support required to wean from cardiopulmonary bypass was less in the IAWBC group compared with the IACBC group (p<0.0001). CONCLUSIONS: IAWBC with 30 minutes of ischemia provides to be clinically acceptable myocardial protection for coronary bypass surgery. 相似文献