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81.
Vural E  Suen JY  Hanna E 《Head & neck》1999,21(8):703-706
BACKGROUND: The purpose of this article is to define the outcome of intracranial extension of inverted papilloma and outline a rationale for management of this rare clinical presentation. METHODS: A review of patients with intracranial extension of inverted papilloma reported in the literature (18 patients), or treated in our institution (3 patients ) was performed. The data of these 21 patients were consolidated with regard to clinical presentation, treatment, and outcome. Nine patients, including 1 of our cases, had coexisting squamous cell carcinoma and therefore were excluded from the analysis. Twelve patients with "pure" inverted papilloma formed the basis of this study. RESULTS: The majority of patients (83%) with intracranial inverted papilloma had recurrent disease. Patients with extradural disease had a survival rate of 86% with an average follow-up of 4.4 years. Eighty-six percent of these survivors were treated with craniofacial resection. In contrast, 75% of patients with intradural inverted papilloma were dead of disease with an average follow-up of 9.3 months regardless of the treatment modality. CONCLUSIONS: Intracranial extension of inverted papilloma is mostly associated with recurrent disease. Intracranial extradural inverted papilloma can be effectively controlled with craniofacial resection. Intracranial intradural involvement of inverted papilloma has a poor prognosis regardless of treatment. Aggressive treatment of intranasal inverted papilloma may be the most important factor in preventing intracranial presentation.  相似文献   
82.
Jallo GI  Koslow M  Hanna BA  Carson LA 《Neurosurgery》1999,44(5):1138-1141
OBJECTIVE AND IMPORTANCE: Although Propionibacterium acnes is a common inhabitant of human skin, it is an uncommon pathogen in postoperative infections. We report three cases of postoperative wound infection/osteomyelitis caused by P. acnes. CLINICAL PRESENTATION: Three patients underwent craniotomy for a supratentorial meningioma and had a dural allograft at the time of closure. The patients presented several weeks after surgery with clinical evidence of a wound infection. INTERVENTION: All patients were diagnosed with P. acnes infection and treated for this pathogen with appropriate antibiotics. The bone flap was removed in two patients. After antibiotic therapy, all patients demonstrated no further evidence of infection. CONCLUSION: To our knowledge, this is the first published report of P. acnes infection in patients with a dural substitute. The source of infection cannot be confidently ascertained; however, two patients had strains of P. acnes from one brand of graft, which were indistinguishable by pulsed field gel electrophoresis typing.  相似文献   
83.
PURPOSE: To determine outcomes and treatment toxicities in patients with optimal (< or = 1 cm residual) Stage III ovarian carcinoma treated with three courses of cisplatin-cyclophosphamide, surgical reassessment (SRA), and hyperfractionated whole abdominal irradiation (WAI). METHODS AND MATERIALS: Forty-two eligible patients entered this prospective Phase II study conducted by the Gynecologic Oncology Group (GOG). Disease characteristics were as follows: age range, 32-76 years (median 58); Stage IIIA (n = 1, 2%), IIIB (n = 2, 5%), IIIC (n = 39, 93%); histology-serous papillary (n = 21, 50%); other (n = 21, 50%); Grade 1 (n = 1, 2%); 2 (n = 14, 33%); 3 (n = 27, 54%); residual disease after initial surgery (present: n = 23, 55%; absent: n = 19, 45%). Five patients progressed while on chemotherapy, could not be effectively cytoreduced, and were not eligible for WAI. Of the remaining 37 patients, 35 received WAI. Surgical reassessment was not performed in five patients. RESULTS: Of 37 patients with known SRA status after chemotherapy, 21 (57%) were grossly positive, 4 (11%) were microscopically positive, and 12 (32%) were negative. Based on measurements recorded following initial laparotomy and surgical reassessment, progression during chemotherapy was noted in 40%, stage disease in 37%, and objective response in 23%. Toxicity during hyperfractionated WAI was limited and reversible. No patient beginning WAI failed to complete or required a significant treatment break. Following WAI, six patients underwent laparotomies for abdominal symptoms; five had recurrent disease. Five additional patients were managed conservatively for small bowel obstruction (SBO) or malabsorption, of whom three subsequently developed recurrence. Twenty-two patients having pelvic boosts were significantly more likely to require management for gastrointestinal morbidity (p = 0.0021). Considering all eligible patients, median disease-free and overall survivals were 18.5 and 39 months, respectively. Considering patients completing chemotherapy and WAI, median disease-free and overall survivals were 24 and 46 months, respectively. CONCLUSIONS: (a) Disease progression occurred within three cycles of cisplatin and cyclophosphamide chemotherapy in 40% of patients with optimal (< or = 1 cm residual) Stage III ovarian carcinoma. (b) Following limited chemotherapy, hyper-fractionated WAI was acutely well tolerated. (c) Late radiation-related toxicity was observed in only three patients (8.6%) in the absence of recurrent disease. Late gastrointestinal morbidity was significantly associated with the administration of a pelvic radiotherapy (RT) boost. (d) Short duration chemotherapy followed by SRA and hyperfractionated WAI without a pelvic boost is a promising management option for patients with optimal Stage III ovarian cancer. A Phase III trial will be necessary to determine how this treatment strategy compares with chemotherapy or RT alone in this patient population.  相似文献   
84.
The effect of butylated hydroxyanisole (BHA) administrationon the hepatic monooxygenase system of nuclear and microsomalfraction was investigated in male mice. Addition of BHA to thediet significantly lowered the content of cytochrome P-450 inliver nuclei and increased the specific activity of NADPH-cytochromec reductase and the content of cytochrome b5 in liver microsomes.Incubation of benzo[a]pyrene (BP) with liver nuclei from BHA-fedmice resulted in inhibition of binding of BP metabolites tonuclear macromolecules by 50% compared with control. However,there was no effect of BHA on the binding of BP metabolitesto macromolecules when BP was incubated with added DNA and livermicrosomes from BHA-fed mice. It has been postulated that modificationof nuclear monooxygenases by BHA may play a role in the inhibitoryeffect of BHA on BP carcinogenesis.  相似文献   
85.
To investigate the effects of growth hormone (GH) on the reversal of growth failure in uremia, recombinant human GH (rhGH) was administered to rats with chronic renal failure (CRF). The dosage of rhGH was 3 IU/day (i.p.) for 13 days after the induction of CRF by 5/6 nephrectomy. Animals were classified into four groups: untreated nephrectomized rats (NX,n=40), GH-treated nephrectomized rats (NX+GH,n=18), sham-operated rats fed ad libitum (SHAMAL,n=27), and sham-operated rats pair-fed with 10 NX rats (SHAMPF,n=10). NX and NX+GH rats developed a similar and moderate degree of CRF, serum urea nitrogen being (mean±SEM) 49±3 and 54±4 mg/dl, respectively, compared with 16±4 and 19±0 mg/dl in SHAMAL and SHAMPF groups. Weight (56.0±3.3 g) and length (3.5±0.1 cm) gains of NX rats were lower than those of SHAMAL rats (94.2±4.0 g,P<-0.0001 and 4.1±0.2 cm,P<-0.01). Growth of the SHAMPF group and the matched NX rats was not significantly different. Weight (56.2±5.0 g) and length (3.4±0.2 cm) gains of NX+GH and NX rats were similar, the beneficial effect of GH therapy on growth being observed in only those animals with more severe degrees of uremia. This growth-promoting action resulted from greater food efficiency and not from stimulated food intake. The hypercholesterolemia seen in NX rats, 81±2 mg/dl versus 55±3 mg/dl in SHAMAL (P0.0001), was not increased in the NX+GH group, 87±3 mg/dl. There was a positive and significant correlation between serum cholesterol and serum urea nitrogen values in NX and NX+GH animals. This study suggests that growth impairment of mild CRF is mainly due to malnutrition and is refractory to GH administration. GH therapy improves the growth rate of animals with advanced CRF without aggravating their lipid abnormalities.  相似文献   
86.
87.
PURPOSE: BRCA1-related breast cancers are more frequently estrogen receptor (ER) negative than are either BRCA2-related or nonhereditary breast cancers. The relationship between ER status and other clinical features of hereditary breast cancers has not been well studied. EXPERIMENTAL DESIGN: ER status, grade, and histological tumor type were evaluated in 1131 women with invasive breast cancer, ascertained at 10 centers in North America. There were 208 BRCA1 mutation carriers, 88 BRCA2 carriers, and 804 women without a known mutation. We stratified the patients by mutation status, grade, age, and histological type and calculated the percentage of ER-positive tumors within each stratum. RESULTS: BRCA1 mutation carriers were more likely to have ER-negative breast cancers than were women in other groups, after adjustment for age, grade, and histological subtype (P < 0.001). Only 3.9% of BRCA1-related breast cancers were ER-positive cancers occurring in women in their postmenopausal years. The direction and magnitude of the change in ER status with increasing age at diagnosis in BRCA1 carriers was significantly different from in BRCA2 carriers (P(intercept) = 0.0002, P(slope) = 0.04). Notably, changes in ER status with age at diagnosis for BRCA1 carriers and noncarriers were almost identical (P(slope) = 0.98). CONCLUSIONS: The strong relationship between the presence of a BRCA1 mutation and the ER-negative status of the breast cancers is neither a consequence of the young age at onset nor the high grade but is an intrinsic property of BRCA1-related cancers. The ER-negative status of these cancers may reflect the cell of origin of BRCA1-related cancers.  相似文献   
88.
89.
A hemopoietin with the ability to accelerate both platelet and granulocyte recovery after intensive chemotherapy would have great clinical utility. The recombinant fusion protein composed of human granulocyte-macrophage colony-stimulating factor and interleukin-3 (PIXY321), showed some promise in early adult trials. However, studies for pediatric patients are limited, and there are no systematic data on the pharmacokinetics of PIXY321 given over prolonged periods at current dosage levels. Purpose: To determine the safety, clinical effects and plasma concentrations of increasing doses of PIXY321 in children treated with myelosuppressive chemotherapy. Methods: A total of 39 children with relapsed or high-risk solid tumors were enrolled in this phase I/II study. PIXY321 was administered once or twice daily by subcutaneous injection in total doses of 500 to 1000 μg/m2 per day for 14 days after each course of chemotherapy with ifosfamide, carboplatin, and etoposide (ICE). Pharmacokinetic studies were performed on day 1 of the first course in 33 patients and repeated on day 14 in 13 patients (once-daily schedule only). Results: Although mild local skin reactions and fever were frequent, no dose-limiting toxicity was identified at the maximum dose studied (1000 μg/m2 per day). There were no statistically significant differences in chemotherapy-induced hematologic toxicity with increasing doses of PIXY321 or with twice-daily vs once-daily dosing. On day 1, the median PIXY321 clearance was 657 ml/min per m2 (range 77–1804 ml/min per m2) and the median half-life was 3.7 h (range 2.1–20.8 h). On day 14, clearance increased in all patients studied (median increase 63%), with a corresponding decrease in the median 12-h concentration (from 1.2 to 0.25 ng/ml). Maximum concentrations were <1 ng/ml in 81% of patients, and only two patients had maximum plasma concentrations equivalent to those required for consistent activity in vitro. Conclusions: The recombinant fusion protein PIXY321 proved safe in children treated with myelosuppressive ICE chemotherapy but had no demonstrable clinical benefits. The pharmacokinetic studies suggest that the observed lack of hematologic benefit may be explained by low plasma concentrations resulting from increased clearance with prolonged administration. Moreover, the significant increase in PIXY321 systemic clearance in the absence of increased circulating myeloid cells suggests that the upregulation of either extravascular compartment hematopoietic progenitor cells or nonhematopoietic cells may play an important role in controlling circulating concentrations of this unique cytokine. These findings highlight the importance of a thorough assessment of the systemic disposition of cytokines when determining the dose and schedule necessary to achieve clinical activity in patients. Received: 29 January 1997 / Accepted: 9 May 1997  相似文献   
90.
OBJECTIVES: To characterise the clinical and electrophysiological features and to determine the molecular genetic basis of pure paramyotonia congenita in a previously unreported large Irish kindred. METHODS: Clinical and neurophysiological examination was performed on three of the five affected family members. Five unaffected and three affected members of the family were available for genetic testing. Direct sequence analysis of the SCN4A gene on chromosome 17q, was performed on the proband's DNA. Restriction fragment length polymorphism (RFLP) analysis was used to screen other family members and control chromosomes for the SCN4A mutation identified. RESULTS: Each affected member had clinical and examination features consistent with pure paramyotonia congenita. Electrophysiological studies disclosed a 78% drop in compound muscle action potential (CMAP) amplitude on cooling to 20 degrees C. DNA sequence analysis identified a heterozygous point mutation G4367A in exon 24 of the SCN4A gene which segregated with paramyotonia and was absent in 200 control chromosomes. The mutation is predicted to result in a radical amino acid substitution at a highly conserved position within the voltage sensing fourth transmembrane segment of the fourth repeated domain of the sodium channel. CONCLUSIONS: The G4367A mutation is likely to be pathogenic and it associates with a pure paramyotonia phenotype. In keeping with other paramyotonia mutations in this region of the skeletal muscle sodium channel, it is predicted that this mutation will impair voltage sensing or sodium channel fast inactivation in a temperature dependent fashion. This study provides further evidence that exon 24 in SCN4A is a hot spot for paramyotonia mutations and this has implications for a DNA based diagnostic service.  相似文献   
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