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991.
We have developed an implant heating system (IHS) for interstitial hyperthermia of brain tumors. IHS consists of three compartments: ferromagnetic implant with low Curie point, induction coil and generator to produce high frequency magnetic field. The device works as follows: It is heated up to a Curie temperature (Tc) by Eddy current under the magnetic field. Heat generated in the implant is conducted to the tumor tissue into which it has been implanted. To evaluate the effect of this hyperthermia, a brain tumor model was produced by innoculation of VX2 tumor cells and treated either by hyperthermia with IHS alone, chemotherapy with ACNU alone, or with a combination of both. The longest survival was obtained by the combined treatment, and significant prolongation of survival was found in the single treatment groups. In the Phase I clinical trial, one or several implants (1.8 mm X 15 mm, Tc = 68 degrees C) made of Fe-Pt alloy were placed in the tumor by CT guided stereotactic procedure, or manually during craniotomy. Hyperthermia of above 42 degrees C for 30 to 60 minutes twice a week was brought about in ten cases of malignant brain tumor. CT evaluation was made in nine cases treated for more than ten times in this way. Five out of the nine cases responded to this hyperthermia with irradiation. In conclusion, a safe, repeated and longterm treatment was possible without significant side effects. The hyperthermia with IHS may also be applicable to benign intracranial tumors and neoplasms in other part of body as well.  相似文献   
992.
Aneurysms of the inferior left ventricular wall represent only a small fraction of all aneurysms that have been reported in surgical series. And in comparison to anterior left ventricular aneurysms, a comparatively higher percentage of reported inferior wall aneurysms was classified as false. A 73-year-old male was admitted for acute inferior myocardial infarction. Three weeks after admission, cardiac catheterization was carried out. Coronary arteriography revealed triple vessel disease and left ventriculography showed an aneurysm of the inferior left ventricular wall, whose feature near the mitral annulus was multiple fenestrations. Left ventricular aneurysmectomy and aortocoronary bypass grafting to the left anterior descending artery were simultaneously performed under cardiopulmonary bypass with moderate hypothermia. The pathological feature was a true aneurysm. The postoperative course was uneventful.  相似文献   
993.
We investigated the effects of energy restriction on the pituitary-ovarian axis and on a hormone responsive gene, the mouse mammary tumor virus (MMTV). Female C3H/SHN F1-hybrid mice, known to display a high incidence of mammary tumors, ate an energy-restricted diet (48 kcal/wk) or a control diet (95 kcal/wk) beginning at the time of weaning. By 67 wk of age, 12 of 32 mice in the control group, but none of the 33 mice in the energy-restricted group, had developed mammary tumors. Six tumor-free mice from each group were studied in detail at 67 wk of age. All six tumor-free control mice, but none of the six energy-restricted mice, showed uterine endometrial hyperplasia at autopsy. Mice subjected to energy restriction did not display an estrous cycle. The average levels of MMTV mRNA in mammary glands and uteri were strongly reduced by energy restriction. MMTV mRNA levels in mammary glands from control mice were two orders of magnitude lower than those in mammary tumors. Energy restriction lowered the percentage of pituitary mammatropes and suppressed proliferation of mammatropes with advancing age. Energy restriction thus appeared to inhibit endometrial hyperplasia and to decrease MMTV production at the mRNA level in the mammary glands and in the uterus. These effects may be a consequence of hormonal changes originating at the pituitary-ovarian axis.  相似文献   
994.
A case of Beh?et disease associated with aortic valve regurgitation treated with aortic valve replacement is reported. The patient was treated successfully with special surgical techniques for prevention of post operative paravalvular leakage and occurrence of pseudo aneurysm because the patient was under long-term steroid therapy for Beh?et disease.  相似文献   
995.
A case of indirect carotid-cavernous sinus fistula treated by combined transarterial and transvenous embolization is described. A 49-year-old woman with a right indirect carotid-cavernous sinus fistula draining solely to the right superior ophthalmic vein was treated first by transarterial embolization with polyvinyl alcohol particles. Then, by approaching through the superior ophthalmic vein from the right external jugular vein, the cavernous sinus was embolized with platinum wire using a tracker microcatheter, which resulted in marked clinical improvement. Transvenous embolization by approaching from the external jugular vein through the superior ophthalmic vein represents a promising alternative when shunted blood drains anteriorly to the superior ophthalmic vein.  相似文献   
996.
A total of 267 infants and children who underwent the arterial switch operation for transposition of the great arteries in the 6 years before Jan. 1, 1988 in six main Japanese institutions were entered into this review. The current status of patients surviving more than 1 year after the operation were evaluated along with early operative results. One hundred forty-six patients had an intact ventricular septum, 103 had a significant ventricular septal defect, and 18 had so-called Taussig-Bing anomaly of the transposition type. Eighteen patients were less than 28 days of age, 73 were 1 to 5 months of age, and 176 were older than 6 months of age at the time of operation. The overall mortality rate was 35% in the first 3 years and 12% in the more recent 3 years. There was a significant difference between the overall mortality rate of primary and two-stage repair (22% versus 10%, p = 0.047) in patients with intact ventricular septum. The overall mortality rate in patients with type B or C coronary arteries of Yacoub, and Radley-Smith's classification was significantly higher than that of other types of arteries (86% versus 18%, p = 0.0001). A total of 156 patients survived more than 1 year after the operation, and 44 children (28%) were noted to have supravalvular pulmonary stenosis (greater than 20 mm Hg). This complication was more common in patients operated on in the newborn period. Trivial or mild aortic regurgitation was noted in 29 patients (19%) and was more common in patients with two-stage than with primary repair (24% versus 14%). Aortic regurgitation was significantly more prevalent in patients in whom coronary arteries were implanted into slits or U-shaped defects than in those whose arteries were implanted into punched-out holes made on the pulmonary root (28% versus 8%, p = 0.049). Normal sinus rhythm was present in 97% of 154 patients and left ventricular ejection fraction was within the normal range in 97% of 115 patients at catheterization 1 to 5 months after the operation.  相似文献   
997.
A 57-year-old male patient with aortic regurgitation and aneurysm of the ascending aorta and the aortic arch underwent aortic valve replacement and graft replacement from the ascending aorta to the aortic arch. The operation was done using cardio-pulmonary bypass and selective cerebral perfusion with deep hypothermia. Postoperative DSA revealed no dilatation of the sinus Valsalva and a good configuration of the anastomosis. It seems that selective cerebral perfusion with deep hypothermia is a safe method to prevent cerebral damage in a case of arch aneurysm.  相似文献   
998.
Immunological studies were performed in 87 patients with chyluria referred to our clinic from January 1982 to December 1988. White blood cell count in 78 patients was 5210.3 +/- 1440.9/mm3. The fraction and the number of lymphocyte were 18.7 +/- 9.5% and 934.1 +/- 521.6/mm3, respectively: they were lower than normal limit. The percentages of T and B lymphocytes studied in 46 patients were 79.3% +/- 11.2% (normal range: 76-86) and 10.4 +/- 7.9% (normal range: 8-16), respectively: both lymphocytes tended to decrease in percentage. Lymphocyte blast formation stimulated with phytohemagglutinin (PHA) was carried out in 20 patients. The mean of the blast formation was 17410.0 +/- 10275.1 c.p.m. (normal range: 377700-62400), and much lower than normal value. Of 22 patients who had PPD skin test, only 9 (40.9%) were positive. These findings signified that cellular immunity was suppressed in patients with chyluria. On the other hand, the value of immunoglobulin was within normal range (IgG: 1325.3 +/- 475.6 mg/dl, IgA: 242.0 +/- 98.3 mg/dl, IgM 130.4 +/- 95.9 mg/dl). Study on the values of laboratory examinations showed statistically positive correlation between total lymphocyte population and T cell number, and between total lymphocyte population and lymphocyte blast formation. In patients with chyluria, serious sequelae have not been reported. However, care should be taken for possible opportunistic infection and, particularly, malignant tumors because suppression of cellular immunity may be one of the promoting factors of malignant tumors.  相似文献   
999.
1000.
The synthesis of the title compounds starting from 2-Chlormethylbenzdioxan and Tetrahydroisochinolines is presented. Their actions on the platelet aggregation and the inhibition of alpha-adrenoceptors at the isolated rabbit aorta and the vas deferens of the guinea pig were investigated.  相似文献   
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