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91.
Metastatic tumors in the sellar and parasellar regions are uncommon and rarely detected in clinical practice. We present four cases of sellar and parasellar metastatic tumors, which metastasized from distant organ in one case and extended directly from adjacent structures in three. Common presenting symptoms were cranial neuropathies, headache and facial pain. Invasion into the cavernous sinus was noted in all cases. We report rare cases of sellar and parasellar metastases. Also, we should consider the possibility of metastasis in these regions for patients who showed the above clinical presentations in systemic cancer patients. In extensive diseases, transient symptomatic relief could be obtained by direct surgical management, even in restricted degree.  相似文献   
92.
93.
Transjugular intrahepatic portosystemic shunt (TIPSS) is a promising method of treatment for gastric or esophageal variceal bleeding. This study was performed to determine the prognostic factors contributing to the survival of patients after TIPSS for gastric or esophageal variceal bleeding. One hundred and fifty-five patients who underwent TIPSS between September 1991 and March 2001 were followed up by clinical examination, upper gastrointestinal endoscopy, and Duplex sonography. The mean portohepatic pressure gradient prior to TIPSS was 20.5+/-9.93 mmHg and dropped to 10.7+/-6.62 mmHg after TIPSS (p<0.001). The cumulative survival rate was 75.1% at 6 months, 66.6% at 1 yr, 58.4% at 2 yr, and 38.1% at 5 yr. Survival after TIPSS was inversely related to the Child-Pugh classification (p<0.05). The rebleeding rate was 18.3% at 6 months, 21.0% at 1 yr, 32.8% at 2 yr, and 53.1% at 5 yr. The causes of deaths were hepatic failure (53.5%), recurrent variceal bleeding (11.6%), pneumonia (4.6%), sepsis (3.5%), hepatic encephalopathy (2.3%), and unknown (17.4%). Multivariate analysis (Cox proportional hazard model) revealed that the Child-Pugh classification and age were statistically significant independent prognostic factors. In conclusion, TIPSS is an effective method of treatment for variceal bleeding in cases where other treatment modalities including endoscopic therapy are unsuccessful and the most important prognostic factors are preprocedural hepatic reserve (Child-Pugh class) and age.  相似文献   
94.
This study investigated whether immunostimulatory DNA sequences (ISS) induce a transient or sustained inhibition of Th2 responses to inhaled antigen. We sensitized mice with subcutaneous injections to develop a Th2 response to ovalbumin (ova) and then administered a dose of ISS prior to ova inhalation challenge. Mice were then rechallenged with ova by inhalation a second time at varying time points after the first ova inhalation (1 to 8 weeks later) to determine whether the ISS dose administered prior to the first ova inhalation protected against a subsequent second ova inhalation challenge. A single dose of ISS inhibited the Th2 response to the first inhalation of ova antigen, as well as 4 weeks later to the second inhalation of ova. However, ISS did not inhibit a Th2 response to the second inhalation of ova 8 weeks later. The reversible inhibition of Th2 responses at 8 weeks suggests the need for repeated ISS administration at monthly intervals.  相似文献   
95.
BACKGROUND: Early administration of high doses of dexamethasone may reduce the risk of chronic lung disease in premature infants but can cause complications. Whether moderate doses would be as effective but safer is not known. METHODS: We randomly assigned 220 infants with a birth weight of 501 to 1000 g who were treated with mechanical ventilation within 12 hours after birth to receive dexamethasone or placebo with either routine ventilatory support or permissive hypercapnia. The dexamethasone was administered within 24 hours after birth at a dose of 0.15 mg per kilogram of body weight per day for three days, followed by a tapering of the dose over a period of seven days. The primary outcome was death or chronic lung disease at 36 weeks' postmenstrual age. RESULTS: The relative risk of death or chronic lung disease in the dexamethasone-treated infants, as compared with those who received placebo, was 0.9 (95 percent confidence interval, 0.8 to 1.1). Since the effect of dexamethasone treatment did not vary according to the ventilatory approach, the two dexamethasone groups and the two placebo groups were combined. The infants in the dexamethasone group were less likely than those in the placebo group to be receiving oxygen supplementation 28 days after birth (P=0.004) or open-label dexamethasone (P=0.01), were more likely to have hypertension (P<0.001), and were more likely to be receiving insulin treatment for hyperglycemia (P=0.02). During the first 14 days, spontaneous gastrointestinal perforation occurred in a larger proportion of infants in the dexamethasone group (13 percent, vs. 4 percent in the placebo group; P=0.02). The dexamethasone-treated infants had a lower weight (P=0.02) and a smaller head circumference (P=0.04) at 36 weeks' postmenstrual age. CONCLUSIONS: In preterm infants, early administration of dexamethasone at a moderate dose has no effect on death or chronic lung disease and is associated with gastrointestinal perforation and decreased growth.  相似文献   
96.
Kim EK  Jeong JH  Youn HS  Koo YB  Roe JH 《Current genetics》2000,38(5):283-290
The gene structure and expression of the linear mitochondrial plasmids of the white-rot fungus Pleurotus ostreatus, pMLP1 and pMLP2, were analyzed. Cleavage by proteinase K and exonucleases indicated that the 5′ ends of pMLP1 and pMLP2 DNAs were associated with terminal proteins. Nucleotide sequencing of the entire pMLP1 DNA revealed that it consists of 9,879 bp with terminal inverted repeat (TIR) sequences of 381 bp. The end sequence of TIR in pMLP1 is 3′-CCCCC-5′, similar to those of Escherichia coli phage PRD1. The pMLP1 plasmid harbors two long open reading frames (ORF1 and ORF2) and at least one minor ORF (mORF1). The deduced product of ORF1 is homologous to RNA polymerases of yeast mitochondria and several bacteriophages, whereas that of ORF2 is homologous to the protein-primed DNA polymerases of family B type. The mORF1 encodes a highly basic protein, most likely a TIR-binding protein, with no apparent sequence homology in the database. Expression of the predicted gene products from pMLP1 in mitochondria was demonstrated by Western blot analysis using antibodies against various expressed regions of pMLP1 ORFs. A plasmid-free strain, generated by curing with ethidium bromide, did not express any of these gene products. Terminal proteins of 70 kDa (TP1) and 73 kDa (TP2) were identified from pMLP1 and pMLP2, respectively. Western blot analysis indicated that TP1 was generated from the N-terminal half of the full-length product of ORF2 encoding a putative DNA polymerase. Received: 9 February 2000 / Accepted: 18 July 2000  相似文献   
97.
Radiation proctitis is a frequent acute complication encountered with pelvic irradiation. This study was aimed at establishing the optimal radiation dose for radiation-induced proctitis in rats. Female Wistar rats were used. The rectal specimens were examined morphologically at 5th and 10th day following 10-30 Gy irradiation in single fraction. With increasing dose, mucosal damage became worse, and there was a prominent reaction after > or =15 Gy. We selected 17.5 Gy as an optimal dose for radiation proctitis and examined specimens at day 1-14 and at week 4, 6, 8, and 12 after 17.5 Gy. The rectal mucosa revealed characteristic histological changes with time. An edema in lamina propria started as early as 1-2 days after irradiation and progressed into acute inflammation. On day 7 and 8, regeneration was observed with or without ulcer. Four weeks later, all regeneration processes have been completed with end result of either fibrosis or normal appearing mucosa. This study showed that the radiation injury of the rectum in rat develops in dose-dependent manner as it has reported in previous studies and suggested that 17.5 Gy in single fraction is the optimum dose to evaluate the protective effect of various medications for radiation proctitis in face of the clinical situation.  相似文献   
98.
99.
Summary.  We have evaluated PCR–RFLP as a practical method for rapid typing of enteroviruses causing aseptic meningitis in Korea. Through blind examination of 80 clinical isolates from patients with aseptic meningitis, we have compared the results of conventional serotyping with PCR–RFLP based genotyping, which was developed for this study. Among the 80 case isolates, which had been previously typed by routine neutralization test, only 42 cases (52.5%) were matched with typing by PCR–RFLP. The result clearly demonstrated that the enterovirus serotype does not coincide with the genotype. Therefore, the classification of enteroviruses by genotyping with PCR–RFLP, although rapid and simple, may be complicated by regional or seasonal differences. However, the PCR–RFLP method developed in this study is applicable to the epidemiological study of enteroviruses when regional or seasonal differences exist, and is useful in identifying the source of an infection. Received August 6, 2001; accepted April 15, 2002 Published online July 10, 2002  相似文献   
100.
While pleural effusion in multiple myeloma is relatively infrequent, myelomatous pleural effusion is extremely rare. We experienced a 61-year-old woman with IgD-lambda multiple myeloma and pleural effusion. The diagnosis was made originally by pleural biopsy, pleural fluid cytology and immunoelectropheresis of pleural fluid. Transient improvement of the pleural effusion was observed after administration of combination chemotherapy of vincristine, melphalan, cyclophosphamide, prednisone (VMCP)/vincristine, cyclophosphamide, adriamycin, prednisone (VCAP). Two months later, myelomatous pleural effusion recurred and no response to salvage therapy was observed. We reviewed the clinical feature of this case and literature concerning myelomatous pleural effusion.  相似文献   
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