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51.
Summary The achievable concentrations of 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl-3-nitrosourea (ACNU), adriamycin, mitomycin C, vindesine, and epipodophyllotoxin suppressed the natural killer (NK) activity of human peripheral blood lymphocytes in vitro, whereas NK activity was not decreased 24h after incubation with the maximum achievable concentration of cisplatin (cDDP). NK activity of patients treated with 80 mg per square meter of cDDP alone was not decreased for 3 weeks after cDDP administration. In contrast, NK activity of patients treated with the same dose of cDDP and methylprednisolone was significantly decreased 1 week after cDDP administration. It was concluded that methylprednisolone, used as an antiemetic agent, had an immunosuppressive effect.  相似文献   
52.
We report specific changes bilaterally in the basal ganglia and thalamus following reperfusion after complete cerebral ischaemia. A 69-year-old man, resuscitated after cardiac arrest, showed symmetrical lowdensity lesions in the head of the caudate nucleus and lentiform nucleus on CT. MRI revealed methaemoglobin derived from minor haemorrhage in the basal ganglia and thalamus, not evident on CT. We suggest that this haemorrhage results from diapedesis of red blood cells through the damaged capillary endothelium following reperfusion.  相似文献   
53.
Revascularization of the hypogastric artery often tends to be neglected in aortoiliac reconstructive surgery; however, its incomplete revascularization can result in unfavorable complications such as buttock claudication or necrosis, vascular impotence, and colonic ischemia. Multiple vascular lesions in the abdominal aorta and bilateral iliac arteries were reconstructed using a newly designed double bifurcated graft in five male patients. All five patients demonstrated excellent graft limb patency and postoperative improvement of the ankle-brachial pressure index without any clinical signs of ischemia in regions of the hypogastric artery. Thus, we conclude that an aggressive approach toward hypogastric circulation maintenance is essential in aortoiliac reconstructive surgery. By using this double bifurcated graft, rapid and safe revascularization of the bilateral hypogastric arteries concomitant with the external iliac or femoral arteries can be performed.  相似文献   
54.
Desmoid tumors of the chest wall following chest surgery are a rare occurrence. A case of this disease is reported herein together with a review of the literature. A 74-year-old man, who had previously undergone a right lower lobectomy for squamous cell carcinoma of the lung, was referred to our hospital with an abnormal shadow on his chest X-ray. The tumor, located in the right lateral chest wall, was successfully resected by an aggressive, wide extirpation, and a final diagnosis of a desmoid tumor originating in the chest wall was made. When following up patients after surgery for lung cancer, the possibility of desmoid tumors developing in the incised chest wall should therefore be kept in mind.  相似文献   
55.
OBJECT: The goal of this study was to evaluate the results of early surgical evacuation of "packed" intraventricular hemorrhage (IVH) in patients with poor-grade subarachnoid hemorrhage (SAH). METHODS: The authors performed surgery within 24 hours after onset of SAH, identified on neuroimaging as a cast distending the ventricular system, in 74 patients with poor-grade SAH (World Federation of Neurosurgical Societies Grades IV and V) without intracerebral hemorrhage. Eighteen of these patients had packed IVH; in these patients the intraventricular clots were extensively evacuated via frontal corticotomy performed under microscopic view. CONCLUSIONS: Overall, 42% of the 74 patients undergoing craniotomy in the acute stage had favorable outcomes, whereas 30% died. Using multivariate analysis, variables significantly associated with favorable outcome in patients with poor-grade SAH included absence of a packed intraventricular clot on computerized tomography scanning; absence of a history of cardiac disease; and a Glasgow Coma Scale score of 11 or 12. None of the 18 patients who had packed IVH had favorable outcomes and seven of these died. In six recently treated patients with packed IVH, which was examined using fluid-attenuated inversion recovery imaging, extensive periventricular brain damage was found both immediately after surgery and during the chronic stage. Accordingly, the authors believe that irreversible periventricular brain damage is already complete immediately after packed IVH occurs.  相似文献   
56.
We report the clinical course of 2 recipients whose renal allografts were obtained from the same cadaver donor after cardiac arrest. The recipients showed different outcomes after transplantation. Graft biopsy after reperfusion revealed disseminated intravascular coagulation (so-called DIC kidney) and severe acute tubular necrosis (ATN) in both recipients. While one graft showed primary nonfunction, the other graft became functional after a post-operative anuric period. Serial graft biopsies performed during the oligo-anuric period revealed recovery of ATN and no intra-glomerular fibrin thrombi, but development of acute rejection was detected in both recipients. The left kidney graft showed more severe local DIC kidney than the right kidney, as well as more severe acute rejection in the oligo-anuric period. Despite aggressive anti-rejection therapy, the left kidney graft showed primary nonfunction. Therefore, severe acute rejection leading to primary nonfunction might have been related to more severe ischemic injury and more extensive local DIC kidney in the left kidney.  相似文献   
57.
Simultaneous resection of the colon with pancreaticoduodenectomy (PD) is occasionally inevitable to accomplish curative resection in instances when a periampullary tumor involves the mesentery of the colon. However, there is little information regarding short- and long-term outcomes of this aggressive surgery. Among 95 consecutive patients who underwent PD for periampullary malignant tumors, 12 had simultaneous resection of the right colon (group 1) and 83 underwent PD alone (group 2). Intraoperative variables, postoperative morbidity and mortality, and the length of the hospital stay were comparatively analyzed. Survival was also compared between the groups in a subset of 36 pancreatic adenocarcinoma patients. Group 1 included more patients with pancreatic cancer, and portal vein resection was more frequently performed, which seemed to be associated with a significantly longer operating time (640 vs. 510 minutes) and increased total blood loss (1965 vs. 1220 ml). However, morbidity and mortality rates did not differ between the groups (50,0% and 0%, respectively, in group 1; 44.6% and 1.2%, respectively, in group 2). The median hospital stays were 67 and 48 days in groups 1 and 2, respectively. In a subset of 36 pancreatic adenocarcinoma patients, the median progression-free survivals were 6 months in both groups 1 and 2; the median overall survivals were 14 months in group 1 and 12 months in group 2. There was no statistically significant difference in survival between the groups. Simultaneous right hemicolectomy with curative intent at the time of PD could thus be performed safely and may offer a survival benefit even for individuals who have advanced pancreatic cancers with involvement of the transverse mesocolon.  相似文献   
58.
We developed an easy method of measuring the presampling modulation transfer function (MTF) using the square wave chart in digital radiography. In this method, the presampling MTF is measured by Fourier transform of image data of the square wave chart. When Fourier analysis of the sampling data of a square wave is carried out, it is generally difficult to find the starting point and terminal point of the periodic data that should be extracted because of an insufficient number of data. To solve this problem, interpolated data were calculated by using a window function of the frequency domain. The aliasing error was avoided using a characteristic such that the square wave has discrete frequency components. The accuracy of this method was investigated by computer simulation study. Actual measurement of the presampling MTF by this method was also performed with a CR system. These studies indicated the effectiveness of our proposed method in terms of accuracy and ease of use.  相似文献   
59.
60.
The cerebellum is a crucial structure for cognitive function as well as motor control. Benign brain tumors such as schwannomas, meningiomas, and epidermoids tend to occur in the cerebellopontine angle cisterns and may cause compression of the posterior lateral cerebellum near the superior posterior fissure, where the eloquent area for cognitive function was recently identified. The present study examined cognitive impairment in patients with benign cerebellar tumors before and after surgical intervention in order to clarify the functional implications of this region in humans. Patients with cerebellar tumors showed deficits in psychomotor speed and working memory compared with healthy controls. Moreover, these impairments were more pronounced in patients with right cerebellar tumors. Functional magnetic resonance imaging during performance of a lure task also demonstrated that cerebellar tumors affected pattern separation or the ability to distinguish similar experiences of episodic memory or events with discrete, non-overlapping representations, which is one of the important cognitive functions related to the hippocampus. The present findings indicate that compression of the human posterior lateral cerebellum affects hippocampal memory function.  相似文献   
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