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Ishikawa, Japan

Nakamura M.,University of Hyogo | Ishikawa T.,Ishikawa Hospital | Kobashi S.,University of Hyogo | Kobashi S.,Osaka University | And 4 more authors.
Conference Proceedings - IEEE International Conference on Systems, Man and Cybernetics | Year: 2011

This paper describes a trans-skull ultrasonic system that measures the blood flow velocity in brain under skull. In this system, we use an ultrasonic array probe with the center frequency of 1.0 MHz. The system determines the blood flow and locate blood vessel by Doppler effect. This Doppler effect is examined by the center of gravity shift in the frequency domain. We use three silicon tubes of different thickness imitated to blood vessel. We confirmed the change of frequency quantity of Doppler effect according to the water current velocity. The experimental result shows that the system detects the flow velocity by Doppler effect under skull and do automatic extracting method of water current. © 2011 IEEE. Source


Yagi N.,University of Hyogo | Ishikawa T.,Ishikawa Hospital | Hata Y.,University of Hyogo | Hata Y.,Osaka University
IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences | Year: 2014

This paper describes an ultrasonic system that estimates the cell quantity of an artificial culture bone, which is effective for appropriate treat with a composite of this material and Bone Marrow Stromal Cells. For this system, we examine two approaches for analyzing the ultrasound waves transmitted through the cultured bone, including stem cells to estimate cell quantity: multiple regression and fuzzy inference. We employ two characteristics from the obtained wave for applying each method. These features are the amplitude and the frequency; the amplitude is measured from the obtained wave, and the frequency is calculated by the crossspectrum method. The results confirmed that the fuzzy inference method yields the accurate estimates of cell quantity in artificial culture bone. Using this ultrasonic estimation system, the orthopaedic surgeons can choose the composites that contain favorable number of cells before the implantation. Copyright © 2014 The Institute of Electronics, Information and Communication Engineers. Source


Furuhashi K.,Hanabusa Womens Clinic | Ishikawa T.,Ishikawa Hospital | Hashimoto H.,Hanabusa Womens Clinic | Yamada S.,Hanabusa Womens Clinic | And 6 more authors.
Andrologia | Year: 2013

An increased risk of testicular cancer in men with infertility and poor semen quality has been reported. In view of the high cure rates for testicular germ cell tumours, increasing clinical importance is being placed on the protection of fertility. High-dose cytostatic therapy may be expected to cause long-term infertility. Thus, the standard procedure for fertility protection is the cryopreservation of ejaculated spermatozoa or testicular tissue before therapy. Four male patients with azoospermia and two patients with very severe oligozoospermia underwent onco-testicular sperm extraction (TESE). We attempted onco-TESE in patients with azoospermia and very severe oligozoospermia after orchiectomy. Of the patients with testicular germ cell tumours, four had spermatozoa in their testicular tissues. Sertoli cell-only syndrome was found in one patient, and one patient showed maturation arrest without the detection of spermatozoa. Three of six showed seminomatous germ cell tumour, two of six had nonseminomatous germ cell tumour and one patient showed no malignancy. Two patients achieved clinical pregnancy. Fertility challenges in men with cancer are the most straightforward because of the relative ease of obtaining and cryopreserving sperm. Testicular sperm extraction is a useful technique for obtaining spermatozoa before cytotoxic therapy in azoospermic and very severely oligozoospermic cancer patients. © 2012 Blackwell Verlag GmbH. Source


Takashima Y.,University of Hyogo | Kuramoto K.,University of Hyogo | Kuramoto K.,Osaka University | Kobashi S.,University of Hyogo | And 4 more authors.
IEEE International Conference on Fuzzy Systems | Year: 2011

This paper describes a testicular tubules evaluation using 1.0MHz ultrasonic array probe. In this system, we evaluate a diameter of testicular tubules. We employ an ultrasonic array probe with the center frequency of 1.0MHz. We employ evaluation index that cumulative relative frequency of amplitude values. In the experiment, we employ 24 nylon lines as the testicular tubules. Amplitude of large nylon line echo is larger than that of small nylon echo. For the evaluation, we calculate cumulative relative frequency amplitude of acquisition data. Fuzzy if-then rules are made by the cumulative relative frequency of large and small lines. We evaluate a rate of large lines among all lines by using the fuzzy MIN-MAX center-of-gravity method. In this experiment, the proposed method successfully evaluated the rate of the large lines. We changed the rate of large lines in 24 nylon lines, and tested our method 20 times for each rate. We evaluated the rate with 5.77 % in mean absolute error. © 2011 IEEE. Source


Ishikawa T.,Ishikawa Hospital
Asian Journal of Andrology | Year: 2012

The development of intracytoplasmic sperm injection (ICSI) opened a new era in the field of assisted reproduction and revolutionized the assisted reproductive technology protocols for couples with male factor infertility. Fertilisation and pregnancies can be achieved with spermatozoa recovered not only from the ejaculate but also from the seminiferous tubules. The most common methods for retrieving testicular sperm in non-obstructive azoospermia (NOA) are testicular sperm aspiration (TESA: needle/fine needle aspiration) and open testicular biopsy (testicular sperm extraction: TESE). The optimal technique for sperm extraction should be minimally invasive and avoid destruction of testicular function, without compromising the chance to retrieve adequate numbers of spermatozoa to perform ICSI. Microdissection TESE (micro-TESE), performed with an operative microscope, is widely considered to be the best method for sperm retrieval in NOA, as larger and opaque tubules, presumably with active spermatogenesis, can be directly identified, resulting in higher spermatozoa retrieval rates with minimal tissue loss and low postoperative complications. Micro-TESE, in combination with ICSI, is applicable in all cases of NOA, including Klinefelter syndrome (KS). The outcomes of surgical sperm retrieval, primarily in NOA patients with elevated serum follicle-stimulating hormone (FSH) (NOA including KS patients), are reviewed along with the phenotypic features. The predictive factors for surgical sperm retrieval and outcomes of treatment were analysed. Finally, the short-and long-term complications in micro-TESE in both 46XY males with NOA and KS patients are considered. © 2012 AJA, SIMM &SJTU. All rights reserved. Source

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