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991.
In patients with a neck metastasis from an unknown primary with non-squamous cell cancer (non-SCC) histology, the primary is often located outside the head and neck area. We retrospectively evaluated 326 patient records and found 14 patients with non-SCC neck lymph node metastasis from an unknown primary undergoing whole body F-18-fluorodeoxyglucose (FDG) positron emission tomography (PET) with or without coregistered computed tomography (PET/CT). The PET or PET/CT findings were verified by pathological work-up, additional imaging tests, and clinical follow-up. PET detected pathological FDG uptake suspicious for the primary in eight patients. PET or PET/CT findings were true positive in seven patients, true negative in 4, false positive in 1, and false negative in two patients. In one patient PET/CT revealed a synchronous ovarian carcinoma. The results suggest that whole body imaging with FDG PET and PET/CT can be useful to identify unknown primaries of non-SCC origin. However, the work-up of patients undergoing PET or PET/CT in our study was very heterogeneous and the primary was more likely found in patients without extensive imaging before PET scanning. Further studies should evaluate if the histology of a neck nodal metastasis should influence the choice of the imaging method and the role of PET and PET/CT imaging for the work up of patients with a non-SCC neck lymph node metastasis of an unknown primary.  相似文献   
992.
993.
Whereas considerable attention has been devoted to achieving high levels of influenza immunization, the importance of this issue is magnified by concern over pandemic influenza. Most recommendations for vaccine administration address high risk groups such as the elderly and those with chronic diseases, but coverage for hard-to-reach (HTR) populations has had less attention. HTR populations include minorities but also include other primarily urban groups such as undocumented immigrants, substance users, the homeless, and homebound elderly. Obstacles to the provision of immunization to HTR populations are present at the patient, provider, and structural levels. Strategies at the individual level for increasing immunization coverage include community-based educational campaigns to improve attitudes and increase motivation for receiving vaccine; at the provider level, education of providers to encourage immunizations, improving patient–provider interactions, broadening the provider base to include additional nurses and pharmacists, and adoption of standing orders for immunization administration; and at the structural level, promoting wider availability of and access to vaccine. The planning process for an influenza pandemic should include community engagement and extension of strategies beyond traditional providers to involve community-based organizations addressing HTR populations.  相似文献   
994.
We have tested the activity of 4-(S)-amino-5-(4-[4-[2,4-dichloro-3-(2,4-dimethyl-8-quinolyloxymethyl)phenylsulfonamido]-tetrahydro-2H-4-pyranylcarbonyl] piperazino)-5-oxopentyl](trimethyl)ammonium chloride hydrochloride (MEN16132), a novel nonpeptide kinin B(2) receptor antagonist, on bradykinin (BK)-induced inflammatory responses, bronchoconstriction, and hypotension in guinea pigs. After i.v. (1-10 nmol/kg i.v.), intratracheal (i.t.) (10-100 nmol/kg i.t.), or aerosol (0.01-0.1 mM/5 min) administration, MEN16132 inhibited in a dose-dependent manner the bronchoconstriction induced by BK (10 nmol/kg i.v.). MEN16132 was more potent and possessed a longer duration of action as compared with the peptide B(2) receptor antagonist icatibant (HOE140; H-D-Arg-Arg-Pro-Hyp-Gly-Thi-Ser-D-Tic-Oic-Arg-OH trifluoroacetate). After i.v. administration, its inhibitory effect on bronchoconstriction lasted more than 8 h at 30 nmol/kg. When administered by i.v. or i.t. routes, the dose completely inhibiting bronchoconstriction also partially reduced the hypotensive response to BK, whereas after aerosol administration, the inhibitory effect was limited to respiratory level. Intranasal (i.n.) administration of MEN16132 (0.01-0.3 nmol/nostril) reduced, in a dose-dependent and long-lasting manner, the nasal mucosa plasma protein extravasation induced by BK (100 nmol/nostril), and it exerted a complete inhibition at about 30-fold lower dose than icatibant. At 1 nmol/nostril, MEN16132 activity was significant for at least 6 h with no systemic effect measured as inhibition of BK-induced hypotension, and at 10 nmol/nostril, the inhibitory effect lasted for more than 15 h with only a weak effect on hypotension. These findings indicate that in vivo MEN16132 is a potent kinin B(2) receptor antagonist with long duration of action, both after i.v. and local administration. A complete and prolonged inhibition of BK-induced bronchoconstriction or nasal inflammation can be achieved with MEN16132 topical administration (aerosol or i.n.) at doses devoid of systemic effects.  相似文献   
995.
A common polymorphism (I405V) in exon 14 of the cholesteryl ester transfer protein (CETP) gene has been recently associated to healthy aging in Ashkenazi Jewish. In order to study this genetic effect in long-lived individuals with a different ethnicity, we analyzed the allele and genotype distributions of the CETP polymorphism a sample of Italian centenarians. Our result does not confirm the association between the I405V CETP variation and the healthy aging phenotype described in the Ashkenazi Jewish population and suggests that other gene environment interactions contribute to longevity.  相似文献   
996.
PURPOSE: To evaluate the dimensional contour variations of acrylic resin denture bases before and after storage in water. MATERIALS AND METHODS: The fit of 40 bases was evaluated by measuring the thickness of a layer made with silicone placed between the bases and the casts. The measurements were repeated on a new set of silicone layers after having stored the bases in water for 42 days. RESULTS: Significant differences were found both for the maxillary and the mandibular bases. CONCLUSION: Water sorption had an important effect on the contour of the prosthetic bases.  相似文献   
997.
Little is known about the habitual daily masticatory activity of subjects with different vertical craniofacial morphology. The purpose of the present study was to compare the daily long-term muscle activity of short-face subjects with that of long-face subjects as assessed in their natural environment. Digital photographs of the facial profile were obtained from a sample of 300 subjects and the ratio between anterior total and anterior lower facial height was assessed (Vertical Facial Index: VFI). Fourteen long-face and 16 short-face subjects were selected from the opposite tails of the frequency distribution of VFI. Long-term masseter activity was monitored for 8 h d(-1) in the natural environment by means of portable one-channel electromyograph recorders over three working days. Assessments included calculation of the number of activity periods (APs) per h (N/h), their mean amplitude (Amean), and their mean duration (Dur). The maximal electromyogram activity did not differ significantly between the short-face and the long-face subjects. There was no significant difference between the two groups investigated in N/h, in Amean and Dur. The findings suggest that habitual activity of masseter muscle in the natural environment was not influenced by the vertical craniofacial morphology as assessed in the present study.  相似文献   
998.
Serious complications after carbamazepine poisoning, such as coma, seizures, respiratory failure, cardiac conduction abnormalities, and death are more likely with serum levels greater than 170 micromol L(-1). We report a case of a single massive carbamazepine overdose in a 19-year-old male, following attempted suicide, without prior history of seizure disorder. On admission, three hours after ingestion, serum carbamazepine concentration was 179 micromol L(-1) and Glasgow Coma Scale scored 6. The patient was intubated and treated with multiple doses of activated charcoal for 48 hours. Twelve hours after ingestion, two repeated generalised myoclonic seizures were noted when serum carbamazepine levels peaked at 181 micromol L(-1), and were successfully treated with diazepam. Carbamazepine serum level fell within the therapeutic range 63 hours after ingestion and the patient was discharged without any long-term sequelae. As there is no antidote for carbamazepine poisoning, supportive treatment remains the only, but usually potent option.  相似文献   
999.
Gut perforation secondary to the insertion of a biliary stent is an uncommon but potentially life-threatening complication. Duodenal perforation has to be taken into consideration whenever the patient starts to suffer severe abdominal pain after the stenting procedure. An early diagnosis is fundamental in order to avoid further complications. Timely conservative treatment with nasogastric suction, nothing by mouth, antibiotics and stent replacement could prevent infection and consequent development of an abscess. We report a case of duodenal perforation secondary to biliary endoprosthesis dislocation in which, in spite of prompt diagnosis and treatment, a large retroperitoneal abscess developed and a CT-guided drainage proved necessary followed later by a surgical operation.  相似文献   
1000.
OBJECTIVES: We investigated individual- and neighborhood-level factors associated with adolescent initiation of injection drug use. METHODS: Injection drug users (IDUs) who had been injecting 2 to 5 years underwent HIV testing and completed a sociobehavioral risk survey. Modeling techniques accounting for intraneighborhood correlations were used in data analyses. RESULTS: Adolescent-initiating IDUs were less likely than adult-initiating IDUs to report high-risk sex and injection behaviors and more likely to report high-risk networks. African American IDUs from neighborhoods with large percentages of minority residents and low adult educational levels were more likely to initiate injection during adolescence than White IDUs from neighborhoods with low percentages of minority residents and high adult education levels. CONCLUSIONS: Racial segregation and neighborhood-level educational attainment must be considered when drawing inferences about age at initiation of injection drug use and related high-risk behaviors.  相似文献   
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