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91.
Mucormycosis is a rare but invasive opportunistic fungal infection with increased frequency during chemotherapy-induced neutropenia. The clinical infections due to Mucor include rhinocerebral, pulmonary, cutaneous, gastrointestinal and disseminated diseases. The first two are the most common diseases and all entities are associated with a high mortality rate. Still hepatic involvement of Mucor is rarely reported. We experienced a case of hepatic and small bowel mucormycosis in a 56-year-old woman after induction chemotherapy for B-cell acute lymphocytic leukemia. Initial symptoms were a high fever unresponsive to broad spectrum antibiotics and pain in the left lower abdominal quadrant. It was followed by septic shock, deterioration of icterus and progressively elevated transaminase. An abdominal CT demonstrated multiple hypodense lesions with distinct margins in both lobes of liver and pericolic infiltration at small bowel and ascending colon. Diagnosis was confirmed by biopsy of the liver. The histopathology of the liver showed hyphae with the right-angle branching, typical of mucormycosis. The patient was managed with amphotericin B and operative correction of the perforated part of the small bowel was performed. However, the patient expired due to progressive hepatic failure despite corrective surgery and long-term amphotericin B therapy.  相似文献   
92.
In most cases, while schwannoma is sporadically manifested as a single benign neoplasm, the presence of multiple schwannomas in one patient is usually indicative of neurofibromatosis 2. However, several recent reports have suggested that schwannomatosis itself may also be a distinct clinical entity. This study examines an extremely rare case of probable schwannomatosis associated with intracranial, intraspinal and peripheral involvements. A 63-year-old woman presented with a seven-year history of palpable lumps on both sides of the supraclavicular area and hearing impairment in both ears. On physical examination, no skin manifestations were evident. Facial sensory change, deafness in the left ear and decreased gag reflex were revealed by neurological examination. Magnetic resonance imaging revealed multiple lesions of the trigeminal nerves, acoustic nerves, lower cranial nerves, spinal accessory nerve, brachial plexuses, and spinal nerves. Pathological examination of tumors from the bilateral brachial plexuses, the spinal nerve in the T8 spinal position and the neck mass revealed benign schwannomas. Following is this patient case report of multiple schwannomas presenting with no skin manifestations of neurofibromatosis.  相似文献   
93.
Nonvascular intervention of the urinary tract is a well-established uroradiologic subspecialty, which is more important for avoiding invasive open surgery in the age of rising demand about the value of less invasive treatment. Various kinds of nonvascular intervention are recently performed under image-guidance and are as follows: percutaneous nephrostomy, percutaneous nephrostolithotomy, percutaneous dilatation of the urinary tract, sclerotherapy for renal cysts, percutaneous catheter drainage, percutaneous foreign body retrieval and biopsy. Percutaneous nephrostomy is a basic technique to provide a direct access to urinary tract, which makes it possible to perform other interventional procedures. Although nonvascular intervention may produce some complications, it is generally considered to be less invasive than open surgery and has advantages such as short hospital stay, early return to normal life and therefore economic savings. This review is described to help clinicians easily understand the procedures, indications, techniques, and complications with figures of cases the authors experienced.  相似文献   
94.
The purpose of this study is to determine the efficacy of bioactive calcium phosphate obtained from porcine cancellous bone for the treatment of bone defects and nonunion. Porcine cancellous bone blocks were heat treated at 1300 degrees C for 2 h. The chemical composition, calcium-to-phosphate ratio, and microstructure of the porcine bone blocks were examined. For in vivo implantation, bone defects were created on the anteromedial aspect of the proximal tibia in seven beagle dogs and the xenograft bone blocks were placed into these defects. Plain radiographs were taken at 2-week intervals for roentgenographic evaluation. At 12 weeks, the specimens were stained with hematoxylin and eosin (H&E). The composition and morphology of heat-treated porcine cancellous bone were found to be similar to heat-treated human cancellous bone. Radiographs showed union between the host bone/bone-block interfaces. At 12 weeks, uniform and substantial new bone formation was observed. It is concluded that heat-treated porcine cancellous bone demonstrated effective osteoconductivity. This high-temperature heat-treatment technique has several advantages, including decreased risk of disease transmission and immunoreactivity, while also offering excellent biocompatibility.  相似文献   
95.
The use of recombinant severe acute respiratory syndrome-coronavirus (SARS-CoV) nucleocapsid protein (N) enzyme-linked immunosorbent assay (ELISA)-based antibody and antigen tests for diagnosis of SARS-CoV infections have been widely reported. However, no recombinant SARS-CoV spike protein (S)-based ELISA is currently available. In this article, we describe the problems and solutions of setting up the recombinant SARS-CoV S-based ELISA for antibody detection. The SARS-CoV S-based immunoglobulin M (IgM) and IgG ELISAs were evaluated and compared with the corresponding N-based ELISA for serodiagnosis of SARS-CoV pneumonia, using sera from 148 healthy blood donors who donated blood 3 years ago as controls and 95 SARS-CoV pneumonia patients in Hong Kong. Results obtained by the recombinant S (rS)-based IgG ELISA using the regenerated S prepared by dialysis with decreasing concentrations of urea or direct addition of different coating buffers, followed by addition of different regeneration buffer, identified 4 M urea and 1 M sarcosine for plate coating and no regeneration buffer as the most optimal conditions for antibody detection. The specificities of the S-based ELISA for IgG and IgM detection were 98.6% and 93.9%, with corresponding sensitivities of 58.9% and 74.7%, respectively. The sensitivity of the rN IgG ELISA (94.7%) is significantly higher than that of the rS IgG ELISA (P < 0.001), whereas the sensitivity of the rS IgM ELISA is significantly higher than that of the rN IgM ELISA (55.2%) (P < 0.01). An ELISA for detection of IgM against S and N could be more sensitive than one that detects IgM against N alone for serodiagnosis of SARS-CoV pneumonia.  相似文献   
96.
An immunochemical and serological study of a patient with rheumatoid arthritis who developed multiple myeloma and was treated with 1-phenylalanine mustard showed a striking difference in the effect of this drug on the rapidly dividing cells, as opposed to the resting plasma cells. The titres of anti-globulin antibodies such as the IgG serum agglutinators and the IgM rheumatoid factors were little altered although the IgG myeloma spike has disappeared following therapy. Fractionation of two different serum samples from 1966 and 1970 showed the IgG paraprotein to be serologically inactive for anti-globulin activity. This paraprotein was also characterized by producing only a single IgG precipitin line with horse anti-human whole serum antibody while the normal IgG globulins always showed a double line.  相似文献   
97.
Spontaneous acute tumor lysis syndrome with advanced gastric cancer   总被引:3,自引:0,他引:3  
Acute tumor lysis syndrome (TLS) occurs frequently in hematologic malignancies such as high-grade lymphomas and acute leukemia, which are rapidly proliferating and chemosensitive tumors. It occurs rarely in solid tumors and has never been reported in gastric adenocarcinoma. Typical biochemical findings of acute tumor lysis syndrome are hyperuricemia, hyperkalemia, hyperphosphatemia and hypocalcemia in patients with a malignancy. Rapid changes of these electrolytes may cause cardiac arrhythmia, seizure, acute renal failure and sudden death. Therefore, as soon as it is detected, it should be taken care of immediately. Until now almost all cases of TLS associated with solid tumor have developed after cytoreductive therapy in chemosensitive tumors. We report here a case of spontaneous acute tumor lysis in a patient of advanced gastric cancer with hepatic metastases and multiple lymphadenopathy. The biochemical finding of TLS improved with the management and tumor burden also showed slight response to the one cycled combination chemotherapy but the patient died of progressive pneumonia.  相似文献   
98.
Phenylketonuria (PKU) is a genetic disorder secondary to a deficiency of hepatic phenyalanine hydroxylase (PAH). Several mutations in thePAH gene have recently been reported, and linkage disequilibrium was observed between RFLP haplotypes and specific mutations. A new molecular lesion has been identified in exon 7 of thePAH gene in a Hungarian PKU patient by direct sequencing of PCR-amplified DNA. The C-to-T transition causes the substitution of Arg243 to a termination codon, and the mutant allele is associated with haplotype 4 of thePAH gene. The mutation is present in two of nine mutant haplotype 4 alleles among Eastern Europeans and is not present among Western Europeans and Asians. The rarity of this mutant allele and its restricted geographic distribution suggest that the mutational event occurred recently on a normal haplotype 4 background in Eastern Europe.  相似文献   
99.
To determine if alterations in extraocular muscle morphology occur after subchronic oral administration of pyridostigmine bromide, rats were continuously fed 90 mg/kg in meal and examined at 1, 2, 4, 7, and 15 days. Within the first day, blood acetylcholinesterase activity was reduced by 87% and remained inhibited by 74-91% during the study. Light microscopy demonstrated that by day 1 approximately 3% of the extraocular myofibers were shrunken and invaded by inflammatory cells. The most severe degenerative changes consisting of vacuoles and inflammatory cell infiltration occurred at day 1 with progressively less severe changes at days 2 and 4. At days 7 and 15, 1.3-4.5% of the myofibers still exhibited damage. Ultrastructurally, all presynaptic areas were normal but the postsynaptic areas of affected myofibers at days 1, 2, and 4 showed myofilament and Z-band dissolution, mitochondrial inclusions, subneural fold and T-tubule/sarcoplasmic reticulum vacuolization and subneural fold depth reduction. By days 7 and 15, these changes were diminished in some cases and in others alterations appeared similar to day 1. We conclude that subchronic feeding of pyridostigmine bromide induces myopathic rather than neurogenic changes in rat extraocular muscle and that the myopathy is different in these muscles than in the diaphragm from the the same rats.  相似文献   
100.
Co-infection with hepatitis B virus (HBV) and hepatitis C Virus (HCV) is associated with increased frequency in the development of hepatocellular carcinoma (HCC). Here, we demonstrated that HBV X protein (HBx) and HCV core cooperate to transform mouse fibroblast NIH3T3 cells. They additively stimulated cell growth, especially in the absence of serum growth factors. In addition, co-expression of HBx and HCV core had additive effects on the induction of anchorage-independent cell growth as well as on the secretion of matrix metalloproteases, which may contribute to increased metastatic potential. Furthermore, the cells expressing both viral proteins exhibited higher tumorigenicity, as demonstrated in athymic nude mice.  相似文献   
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