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101.
Mutations of the ras gene family appear to be an uncommon genetic alteration in SCCHN. A common region of DNA amplification on chromosome 11q13 has been identified in SCCHN. A cluster of proto-oncogenes (int-2, hst-1, bcl-1, prad-1) has been localized to the 11q13 region. Studies are needed to determine the critical genes in 11q13 whose expression drive the amplicon. Mutations of the p53 tumor suppressor gene are the most common genetic alteration in SCCHN. The hope is that dysregulated oncogenes or tumor suppressor genes may be targets for specific therapy. 相似文献
102.
We have undertaken a series of studies to elucidate the roles of growth factors (FGF-2, EGF, TGF-beta1) and prolactin (PRL) in lacrimal gland function during pregnancy and lactation, and to better understand the status of the immune system within the lacrimal gland during those physiological states. In this initial study, lacrimal glands of pregnant (d15, d29), lactating (9d, 22d), and adult female control rabbits, were evaluated by immunohistochemistry, Western blotting and image analysis. In control rabbits EGF, TGF-beta1, and PRL, were immunolocalized primarily in the apical cytoplasm of intralobular ductal epithelial cells, and acini demonstrated a basement membrane-associated immunopositivity for TGF-beta1. FGF-2 immunolocalized in myoepithelial cells in the basal ductal epithelium and complexed to the basement membrane enclosing ducts and acini. Cells immunopositive for immune cell markers (RTLA and CD18) were apparent primarily around interlobular ducts. In d29 pregnant rabbits immunopositivity for EGF and TGF-beta1 was increased within intralobular ducts, both apically and basally, and within some interlobular ductal epithelial cells. Immunopositivity for PRL was strongest in d29 pregnant rabbits within the apical and basal cytoplasm of intralobular ductal epithelial cells. Immunopositivity for FGF-2 in myoepithelial cells was strong in d15 and d29 pregnant rabbits, although basement membrane-associated immunopositivity around acini was often decreased. Immunostaining for EGF and TGF-beta1 in lactating rabbits was similar to that in d29 pregnant rabbits, although basement membrane-associated immunopositivity around acini was more comparable to controls. By 22d lactation immunopositivity for FGF-2 closely resembled that in controls. Image analysis of pregnant and lactating rabbits demonstrated that cells immunopositive for RTLA and CD18 were less abundant around ducts and more abundant between acini, although in 22d lactating rabbits the size of periductal foci was increased to nearly that of controls. Western blots correlated well with the immunohistochemistry. Our findings demonstrate that pregnancy and lactation are accompanied by a shift in the distributions of growth factors and PRL, suggestive of increased release both apically into the lacrimal fluid and basally into the interstitium. Additional shifts in the distributions of cells of the immune system from periductal foci to interacinar sites suggest that there is a recruitment of immune cells away from ducts and toward the connective tissue interstitium surrounding the acini, possibly as part of a heightened state of immune readiness during pregnancy and lactation. 相似文献
103.
Schechter BA Rand WJ Velazquez GE Williams WD Starasoler L 《American journal of ophthalmology》2002,134(2):268-270
PURPOSE: Two patients with biopsy-proven conjunctival papillomata exhibited complete resolution after treatment with topical Interferon Alfa-2b (IFNalpha2b). DESIGN: Interventional case reports. METHODS: Two patients with monocular biopsy-confirmed conjunctival papillomata were treated with IFNalpha2b, 1 million units/cc, one drop four times daily until clinical resolution was achieved. RESULTS: (Patient 1) The lesion's size was significantly reduced at 1 month. Complete resolution was noted at the 3-month visit. No recurrences were seen 40 months post-treatment. (Patient 2) The lesion completely resolved after 6 weeks of treatment. No recurrence has occurred 18 months post-treatment. No systemic or local side effect of treatment was noted. CONCLUSIONS: Two sizable conjunctival papillomata resolved using topical IFNalpha2b alone. Interferon is usually not considered effective for large solid tumors without surgical debulking. We realize that this is a limited case series, but these cases may serve as a basis for further investigation. 相似文献
104.
105.
Jones ME Karlowsky JA Blosser-Middleton R Critchley IA Thornsberry C Sahm DF 《International journal of antimicrobial agents》2002,19(2):119-123
Haemophilus influenzae (n=2791) and Moraxella catarrhalis (n=1249) isolated from patient specimens during 1999 were collected from 290 laboratories participating in a moxifloxacin surveillance study as part of the LIBRA Surveillance initiative. Isolates were tested for in vitro susceptibility to a panel of agents suitable for the treatment of respiratory tract infections. beta-Lactamase production was identified in 32.2% of H. influenzae and 94.2% of M. catarrhalis. These percentages differed by less than 1.5% from results of a study conducted in 1997-1998 and were similar to results from other recent US surveillance studies. Resistance among H. influenzae to trimethoprim-sulphamethoxazole increased considerably, from 2% in the 1997-1998 study (n=6588 H. influenzae) to 15.5% in the current study. One isolate of H. influenzae had an MIC of 8 mg/l to both levofloxacin and moxifloxacin; all other isolates had MICs of < or =0.5 mg/l and < or =0.25 mg/l, respectively. beta-Lactamase production was found to confer ampicillin resistance in nearly all isolates. For M. catarrhalis, beta-lactamase-negative isolates had MICs < or =0.12-0.25 mg/l for ampicillin and < or =0.03-0.12 mg/l for ceftriaxone. In contrast, beta-lactamase production resulted in MICs of < or = 0.12->16 mg/l for ampicillin and < or = 0.03-4 mg/l for ceftriaxone. All M. catarrhalis had MICs < or =0.12 mg/l for moxifloxacin and < or =1 mg/l for levofloxacin. In summary, antimicrobial susceptibilities and the prevalence of beta-lactamase production in H. influenzae and M. catarrhalis in the United States has remained essentially unchanged from 1997-1998 to 1999. 相似文献
106.
107.
Two-hundred-and-eight acne vulgaris patients were enrolled in a 24-week study to determine the bacterial resistance issues associated with the use of a topical 2% erythromycin gel. It consisted of a 12-week randomized, double-blind, parallel-group treatment phase comparing the active gel versus its vehicle followed by a 12-week single-blind regression phase with gel vehicle only. Bacteriological samples were taken from the face, back and nares for quantification by species and antibiotic resistance characteristics. Acne efficacy was assessed through week 12. The prevalence of erythromycin-resistant coagulase-negative Staphylococci on the face was extremely high (87%) at baseline, increased to 98% by week 12 in the erythromycin-treated group and did not change during regression. The density of these resistant organisms also significantly increased with erythromycin treatment with no change during regression. Similar prevalence and density patterns were also observed on the untreated back and in the nares. Nearly all of the resistant isolates were highly resistant (minimal inhibitory concentrations > 128 microg/ml). Resistance development was confined to the macrolide class of antibiotics. No anti-acne efficacy was observed. 相似文献
108.
109.
OBJECTIVE: The purpose of our study was to evaluate the knees of asymptomatic high-level collegiate basketball players before the beginning of the basketball season to gain an understanding of nonclinical findings in this patient population. SUBJECTS AND METHODS: Bilateral knee MR imaging examinations of 17 varsity basketball players (12 men and five women) were performed before basketball season began. All of the subjects were imaged on a 1.5-T magnet. The MR imaging studies were reviewed by two musculoskeletal radiologists. Structures analyzed were the menisci, ligaments, cartilage, plicae, and bone marrow. The presence of a joint effusion was also noted. RESULTS: Fourteen (41%) of the 34 knees had bone marrow edema, eight (24%) showed signal in the patellar tendon, and 14 (41%) had abnormal cartilage signal or a focal abnormality. Twelve (35%) of the 34 knees showed a joint effusion. Two knees (6%) showed abnormal signal along the infrapatellar plica. Four knees (12%) were noted to have a discoid meniscus. CONCLUSION: An MR examination of the knees of high-level collegiate basketball players may show changes unique to this population. The changes seen on MR imaging in these athletes may be asymptomatic abnormalities. For instance, changes suggestive of patellar tendinopathy were identified in these asymptomatic subjects. 相似文献
110.
Funding priorities for medical research 总被引:1,自引:0,他引:1