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1.
We report a case of infectious endocarditis in a 77-year-old woman who was undergoing maintenance hemodialysis therapy, and who was also having a prosthetic aortic valve replacement. The disease resulted from a local skin infection at the needle puncture site of the arteriovenous fistula. Ampicillin-resistant Staphylococcus aureus was the causal organism. Surgical treatment could not be performed because of associated intracranial hemorrhage due to septic embolism. In spite of intensive treatment with several antibiotics, a ventricular septal abscess just beneath the prosthetic aortic valve progressed to form a ventricular septal fistula. The resultant intracardiac left-to-right shunt led to refractory congestive heart failure. The patient finally died of heart failure. The formation of a ventricular septal fistula is considered to be a rare and extraordinary complication of infectious endocarditis in a hemodialysis patient with aortic valve replacement. Received: July 25, 2001 / Accepted: November 3, 2001  相似文献   
2.
This article documents a patient with lung carcinoma that produced three oncofetal antigens including alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), and human chorionic gonadotropin (hCG). Serum AFP, CEA, and hCG-beta-subunit were extremely high--118,000 ng/ml, 133 ng/ml and 0.9 ng/ml, respectively. Immunohistochemical staining of these tumor markers revealed that these proteins were present in different cells. The pattern of lectin affinity electrophoresis of AFP resembled that of hepatocellular carcinoma. Also investigated was the reactivity of serum CEA to monoclonal antibodies against peptide or sugar moieties. Serum CEA values measured by antipeptide monoclonal antibodies were higher than those measured by antisugar monoclonal antibodies. The demonstration of AFP, CEA, and hCG in different tumor cells suggests that three genomes were not reactivated together in a cell, and the lung carcinoma probably consisted of at least three clones of cancer cells with different phenotypes.  相似文献   
3.
The matrix metalloproteinase matrilysin (MMP-7) is a member of the matrix metallo-proteinase gene family, which is believed to play an important role in tumor invasion and metastasis. We have previously found that matrilysin mRNA is specifically expressed in colorectal cancers and adenomas and that its message is localized in the tumor cells themselves. We examined the effects of activated Ki-ras oncogene on the expression of matrilysin in colon cancer cells. We showed that both mRNA and the enzymatic activity of matrilysin were induced by the introduction of activated Ki-ras into SW1417 colon cancer cells. To understand the mechanisms regulating this induction, we analyzed alterations of AP-1 activity induced by activated Ki-ras, using the chloramphenicol acetyltransferase assay. AP-1 activity in SW1417 cells expressing activated Ki-ras was higher than that in control cells. The gel-shift assay also showed higher levels of AP-1 binding protein in SW1417 cells expressing activated Ki-ras than those in control cells. Our results suggest that activated Ki-ras may play a role in inducing expression of matrilysin through an AP-1-dependent pathway in colon cancer cells.  相似文献   
4.
We report a case of granulocyte-colony stimulating factor producing gastric cancer with multiple liver metastases. A 68-year-old woman who complained of epigastralgia visited our hospital. Upper gastrointestinal endoscopic examination revealed a type-2 gastric cancer. The laboratory data at admission indicated leukocytosis (35,900/microl) and a high level of serum granulocyte-colony stimulating factor (61 pg/mg). Granulocyte-colony stimulating factor producing gastric cancer was diagnosed by immunohistochemistry of biopsy specimen. Since we detected multiple liver metastases, chemotherapy was performed. Granulocyte-colony stimulating factor-producing gastric cancer is relatively rare and we summarize previous reports.  相似文献   
5.
We report herein a case of spontaneous subcapsular hepatic hemorrhage which occurred in a 33-year-old woman 1 day after she had been delivered of her second child by cesarean section following an uneventful pregnancy. She complained of right upper quadrant pain on the 1st postoperative day, and computed tomography (CT) showed subcapsular low-density masses in both liver lobes, while extravasation was demonstrated by CO2 intraarterial digital subtraction angiography (IADSA). The hemorrhage was successfully controlled by transcatheter arterial embolization (TAE). However, on the 3rd day after TAE, an exploratory laparotomy was performed to establish an exact diagnosis to explain the persistent abdominal pain and abnormal liver function tests. Subcapsular hematomas in both lobes were confirmed and no visible laceration was present. The patient recovered gradually by spontaneous absorption of the hematomas and was discharged on the 22nd postoperative day. Spontaneous hepatic hemorrhage associated with pregnancy is a very rare complication, and establishing a correct diagnosis and initiating appropriate therapy are essential for this life-threatening disease.  相似文献   
6.
We have previously reported the production of endothelin, a potent vasoconstrictor peptide, by porcine cerebral microvessel endothelia and suggested its important role in the regulation of local blood flow within the brain. In our present study, radioimmunoassay with anti-porcine endothelin antiserum revealed that endothelin, produced by cerebral microvessel endothelia grown on a filter, is released mainly to the basement membrane side, not the vascular lumen side. This finding suggests that endothelin constricts arterioles locally where it is produced by endothelia. We also found that cerebral microvessel endothelia produce less endothelin under low oxygen pressure and more endothelin under low carbon dioxide pressure. Our results suggest that endothelin has a role in the regulation of cerebral blood flow in response to oxygen and carbon dioxide pressure.  相似文献   
7.
To elucidate the molecular basis for endocrine tumorigenesis, p53 mutations in human endocrine tumors were analyzed by using polymerase chain reaction-single strand conformation polymorphism. Exons 5 through 10 of the p53 gene were studied in genomic DNAs from 134 primary endocrine tumors and 6 human endocrine cancer-derived cell lines. Mutations were detected and identified in 4 endocrine tumors, including one parathyroid adenoma and three thyroid carcinoma cell lines. The sites of these mutations were in exons 5 (codon 151 and 152) and 7 (codon 248 and 255). In all of three tumor cell lines, but not in a parathyroid adenoma, the normal allele encoding the p53 gene was lost. However, p53 mutations were not found in any other endocrine tumors or cell lines. Based upon these results, we concluded that the p53 gene may play a role in the tumorigenesis of a limited number of parathyroid adenoma and thyroid cancers, and that the p53 mutation with an allelic loss of the p53 gene is an important factor in malignant tumorigenesis of the thyroid gland.  相似文献   
8.
9.
The study of intratumoral PO2 in brain tumors   总被引:1,自引:0,他引:1  
The aim of this study was to evaluate the hypoxic cells in the human brain tumor in vivo. Untreated 16 cases of brain tumor were analysed. During the surgery for the purpose of removal of the tumor, needle type-O2 sensors were inserted into femoral artery and in brain tumor to measure PaO2 and intratumoral O2 pressure. A plate type O2 sensor was put on the surface of surrounding brain cortex to measure cortical O2 pressure. These O2 sensors for this study is able to measure O2 pressure continuously and to observe these three O2 pressure simultaneously. Operations were performed endotracheal anesthesia under inhalation of ethrane with maintaining systolic blood pressure 120 mmHg. Setting the rate of O2 and N2O gas inhalation 1/3, PaO2 revealed about 110 mmHg which is similar value as physiological state--1 ATM, air inhalation--. The value of TuO2 and BrO2 were revealed 15.3 +/- 2.3 (mean +/- SE) mmHg and 59.8 +/- 6.5 (mean +/- SE) mmHg. According to these results, it might be said that hypoxic fraction surely exist intratumoral tissue. It is also well known that O2 removes from higher pressure zone to lower pressure zone after O2 was diffused from red blood cell in brain tissue. It might be also mentioned that much lower hypoxic fraction than the value of this study is existing intratumoral tissue. It has long been recognized that hypoxia influences the response of cells and tissues to radiation. However, they have been suspected on the basis of experimental data in vitro. This study showed hypoxic fraction in human brain tumor tissue in vivo.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
10.
The authors review their experience with the bifrontal interhemispheric approach in 603 cases of single anterior communicating artery (ACoA) aneurysms and describe the operative technique. With this approach, the olfactory tracts are dissected, and both A1 segments of the anterior cerebral arteries are identified subfrontally. The interhemispheric fissure is then dissected and A2 segments are followed from the distal portion toward the ACoA complex. Following the administration of a combination of mannitol, vitamin E, and dexamethasone, a temporary clip is placed on at least the dominant A1 segment prior to dissection of the aneurysm itself. Once the aneurysm has been completely freed from the surrounding structures, the neck is ligated and clipped. If the aneurysm ruptures during surgery, temporary clips are placed on both A1 and A2 segments bilaterally and the operation proceeds in a completely dry field. With this method, it is possible to occlude any of the intracranial vessels for up to 40 minutes within 100 minutes of drug administration. To prevent the possibility of rerupture and the development of vasospasm in the period before aneurysm surgery, the authors have adopted a policy of performing ultra-early operations within 48 hours of the onset of symptoms. Among the 257 cases operated on during the 9 years since 1975, one-fifth have been operated on within 48 hours of rupture, and the in-hospital mortality rate has been only 4.3% (11 cases). Follow-up studies have shown that 87% of the 246 surviving patients have returned to useful lives.  相似文献   
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