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61.
A fully automatic radiophotoluminescent glass rod dosimeter (GRD) system has recently become commercially available. This article discusses the dosimetric properties of the GRD including uniformity and reproducibility of signal, dose linearity, and energy and directional dependence in high-energy photon beams. In addition, energy response is measured in electron beams. The uniformity and reproducibility of the signal from 50 GRDs using a 60Co beam are both +/- 1.1% (one standard deviation). Good dose linearity of the GRD is maintained for doses ranging from 0.5 to 30 Gy, the lower and upper limits of this study, respectively. The GRD response is found to show little energy dependence in photon energies of a 60Co beam, 4 MV (TPR20(10)=0.617) and 10 MV (TPR(20)10=0.744) x-ray beams. However, the GRD responses for 9 MeV (mean energy, Ez = 3.6 MeV) and 16 MeV (Ez = 10.4 MeV) electron beams are 4%-5% lower than that for a 60Co beam in the beam quality dependence. The measured angular dependence of GRD, ranging from 0 degrees (along the long axis of GRD) to 120 degrees is within 1.5% for a 4 MV x-ray beam. As applications, a linear accelerator-based radiosurgery system and Cyber-Knife output factors are measured by a GRD and compared with those from various detectors including a p-type silicon diode detector, a diamond detector, and an ion chamber. It is found that the GRD is a very useful detector for small field dosimetry, in particular, below 10 mm circular fields.  相似文献   
62.
Following the determination of the binding characteristics of [3H]SCH 23390 using slide-mounted tissue sections of molded minced forebrain, the effects of chronic methamphetamine (MAP) treatment (at a dose of 4 mg/kg for 14 days) on D1 receptors in the rat brain were studied using quantitative receptor autoradiography. There were no differences in both Kd(app) and Bmax values between vehicle- and MAP-treated rats, indicating that D1 receptors might not be involved in the development of behavioral sensitization in chronically MAP-treated rats.  相似文献   
63.
BACKGROUND: It has been reported that local thermal therapy with a hot pack or paraffin relieves pain. We hypothesized that systemic warming may decrease pain and improve the outcomes in patients with chronic pain. The purpose of this study was to clarify the effects of systemic thermal therapy in patients with chronic pain. METHODS: Group A (n = 24) patients with chronic pain were treated by a multidisciplinary treatment including cognitive behavioral therapy, rehabilitation, and exercise therapy, whereas group B (n = 22) patients were treated by a combination of multidisciplinary treatment and repeated thermal therapy. A far-infrared ray dry sauna therapy and post-sauna warming were performed once a day for 4 weeks during hospitalization. We investigated the improvements in subjective symptoms, the number of pain behavior after treatment and outcomes 2 years after discharge. RESULTS: The visual analog pain score, number of pain behavior, self-rating depression scale, and anger score significantly decreased after treatment in both groups. After treatment, the number of pain behavior was slightly smaller (p = 0.07) and anger score was significantly lower in group B than those in group A (p = 0.05). Two years after treatment, 17 patients (77%) in group B returned to work compared with 12 patients (50%) in group A (p < 0.05). CONCLUSION: These results suggest that a combination of multidisciplinary treatment and repeated thermal therapy may be a promising method for treatment of chronic pain.  相似文献   
64.
We investigated the proteolipid protein (PLP) gene of two boysin a Japanese family with Pelizaeus—Merzbacher disease(PMD), an X-linked neurologic disorder characterized by dysmyelinationin the central nervous system (CNS). The patients showed similarclinical signs from birth and autopsy on the elder brother confirmeda connatal type of PMD. Direct sequencing of the PLP gene andPLP mRNAs from the brain of the PMD patient revealed a G toT transition in exon V of the PLP gene, which leads to a glycineto cystein substitution at residue 220. Allele-specific oligonucleotidehybridization revealed that this mutation was also present inhis brother, but was absent in 100 X chromosomes of normal Japaneseindividuals. Northern blot analysis showed that the mRNA levelsof PLP and myelin basic protein, two major myelin proteins producedby oligodendrocytes, were much reduced in the PMD brain, hence,there was a specific loss of oligodendrocytes. It seems likelythat the substitution is responsible for PMD (connatal type)in this particular family and causes oligodendrocytes deathin the CNS.  相似文献   
65.
It seems to be well established that the direct surgical treatment of intracranial aneurysm such as clipping, trapping and wrapping the aneurysm. These operations have brought about excellent results but are not perfect because recurrent aneurysm and rebleeding of aneurysm have been reported shortly after the operation. However, it is very rare that subarachnoid hemorrhage arising from recurrent aneurysm long time after the operation, authors have experienced 3 cases of recurrent aneurysm in the same region long after the surgery. Two cases were readmitted to our hospital following repeat episode of subarachnoid hemorrhage. Carotid angiogram showed a new small aneurysm locating about the same place where previously operated aneurysm was situated. One of them showed development of new aneurysm at the anterior communicating after 4 years artery the neck clipping, the other one was recurrent aneurysm 9 years after the neck clipping of aneurysm at the anterior communicating artery. Two cases were treated by reclipping and got well. It has been reported in the articles that 20 cases of recurrent aneurysm were located about the same place where previously clipping aneurysm was performed. Causes of such recurrence of already clipped aneurysm could be divided into two groups. First group was considered that the treatment was unsatisfactory, because the clip had been improperly placed. The other group was considered as mechanical failure of aneurysmal clip that resulted in "slipped out," or "broken clip", and local fragility of the arterial wall adjacent to clip edge. Last case had a giant pseudoaneurysm.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
66.
Chronic left ventricular (LV) dysfunction may result from irreversible damage (cell death), stunned myocardium (ST), or hibernating myocardium (HB). However, both of ST and HB are expected to be reversible. In this report, the effects of coronary artery bypass grafting on the regions of ST and HB were evaluated in 37 patients with less than 40% of LV ejection fraction. The patients were divided into two groups. Group I consisted of the patients whose postoperative LV ejection fraction rose by more than 10% compared to the preoperative value. Group II included the remaining patients with no significant improvement. After successful revascularization, 61% of HB changed to ST and 52% of ST to normal in group I. These changes were significant in comparison with group II because 48% of HB and 83% of ST in group II remained unchanged. Immediate or rapid recovery of HB hardly occurred in both of the groups. To recover normal function, HB may pass through a stage of ST on reperfusion. On the other hand, it is difficult to determine whether HB and ST with no significant changes after reperfusion are irreversibly damaged or reversible and take time to return to normal.  相似文献   
67.
A case of female alcoholic who developed liver cirrhosis with small amounts of alcohol by the common use of contraceptive agent was reported. A case was a 33-year-old female who had complained of systemic edema and jaundice. She had been drinking alcohol, while she had been taking the contraceptive agent from 20-year-old. On admission, she had a large amount of ascites with jaundice. She was diagnosed as liver cirrhosis and hepatic failure by CT scanning of abdomen and laboratory data. Her condition was temporarily improved by the abstinence and the treatment. Since she drank under hospitalization, she had to change the hospital and died after 2 months. She had been drinking for only 10 years. Her cumulative alcohol intake was also very small. She may have developed alcoholic cirrhosis with small amount of alcohol because of common use of contraceptive agent with drinking.  相似文献   
68.
Aims:   To evaluate reproductive outcome after laparoscopic myomectomy for intramural myomas in infertile women with or without associated infertility factors.
Methods:   A retrospective study was carried out in 30 infertile women with intramural myomas measuring ≥50 mm in diameter and treated using laparoscopy.
Results:   The overall rate of spontaneous intrauterine pregnancy was 50.0% (15 patients). Of 13 patients with infertility factors associated with the uterine myomas, three (23.1%) became pregnant, whereas 12 of 17 patients (70.6%) with no other associated infertility factor became pregnant. No uterine ruptures were observed. All pregnancies were spontaneous and 13 occurred within 1 year of the operation. In the 10 patients who gave birth by Cesarean section, no adhesions were found on the myomectomy scar.
Conclusions:   On the basis of these results, laparoscopic surgery for myomas appears to offer comparable results to laparotomy. In infertile patients with intramural myoma, pregnancy rates are affected by the presence of other infertility factors associated with the uterine myomas. (Reprod Med Biol 2006; 5 : 31–35)  相似文献   
69.
This study was undertaken to examine whether males develop schizophrenia at a younger age than females, and whether temporal socioeconomic change affects the age at onset of schizophrenia. The subjects were 848 ICD-9 schizophrenics who were admitted to Nihon University Hospital, Tokyo, Japan, during the period of 1955-64 (n = 468 (214 males and 254 females), group A) or during the period of 1982-91 (n = 380 (220 males and 160 females). group B). Schizophrenic males showed an earlier age at onset than schizophrenic females. However, the mean age at onset of schizophrenia did not differ significantly between group A and group B. These results indicate that the gender difference in age at onset of schizophrenia has not been influenced by temporal socioeconomic change.  相似文献   
70.
PURPOSE: We present results of patients with hepatocellular carcinoma (HCC) treated with proton beam therapy. EXPERIMENTAL DESIGN: We reviewed 162 patients having 192 HCCs treated from November 1985 to July 1998 by proton beam therapy with or without transarterial embolization and percutaneous ethanol injection. The patients in the present series were considered unsuitable for surgery for various reasons, including hepatic dysfunction, multiple tumors, recurrence after surgical resection, and concomitant illnesses. The median total dose of proton irradiation was 72 Gy in 16 fractions over 29 days. RESULTS: The overall survival rate for all of the 162 patients was 23.5% at 5 years. The local control rate at 5 years was 86.9% for all 192 tumors among the 162 patients. The degree of impairment of hepatic functions attributable to coexisting liver cirrhosis and the number of tumors in the liver significantly affected patient survival. For 50 patients having least impaired hepatic functions and a solitary tumor, the survival rate at 5 years was 53.5%. The patients had very few acute reactions to treatments and a few late sequelae during and after the treatments. CONCLUSIONS: Proton beam therapy for patients with HCC is effective, safe, well tolerable, and repeatable. It is the useful treatment mode for either cure or palliation for patients with HCC irrespective of tumor size, tumor location in the liver, insufficient feeding of the tumor with arteries, presence of vascular invasion, impaired hepatic functions, and coexisting intercurrent diseases.  相似文献   
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