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971.
972.
973.
Ultrasound, as a diagnostic modality, has been developing rapidly. High-resolution ultrasound machines have been reduced to the size of a laptop computer. Ultrasound can be adopted by otolaryngologists for use within the clinic and the operating room. Ultrasound offers several advantages to the pediatric patient population. It is well tolerated and adds a degree of precision to the physical examination. It can be done repeatedly as lesions evolve and treatment is performed. It is valuable for guidance and therapeutic treatment of lesions in the operating room. It is likely that ultrasound use will continue to rapidly grow and evolve as a tool within the field of otolaryngology.  相似文献   
974.
OBJECTIVES: To characterise comprehensively the antibiotic susceptibility of Neisseria gonorrhoeae in Arkhangelsk, Russia, and to investigate whether the recommended treatment guidelines are updated and effective. METHODS: The susceptibility of N gonorrhoeae isolates, cultured during June-November 2004 mainly from consecutive patients with gonorrhoea (n = 76) in Arkhangelsk, to penicillin G, ampicillin, cefixime, ceftriaxone, ciprofloxacin, erythromycin, azithromycin, kanamycin, spectinomycin and tetracycline was analysed using Etest. Nitrocefin discs were used for beta-lactamase detection. RESULTS: The levels of intermediate susceptibility and resistance to the different antibiotics were as follows: penicillin G 76%, ampicillin 71%, cefixime 0%, ceftriaxone 3%, ciprofloxacin 17%, erythromycin 54%, azithromycin 14%, kanamycin 49%, spectinomycin 0% and tetracycline 92%. Of the isolates 55 (72%) were determined as multiresistant--that is, they showed intermediate susceptibility or resistance to three or more classes of antibiotics. However, none of the isolates were beta-lactamase producing. CONCLUSIONS: In Arkhangelsk, and presumably in many other areas of Russia, penicillins, ciprofloxacin, erythromycin, azithromycin, kanamycin and tetracycline should not be used in the treatment of gonorrhoea if the results of antibiotic susceptibility testing are not available. In Russia, optimised, standardised and quality-assured antibiotic susceptibility testing needs to be established in many laboratories. Subsequently, continuous local, regional and national surveillance of antibiotic susceptibility is crucial to detect the emergence of new resistance, monitor changing patterns of susceptibility and be able to update treatment recommendations on a regular basis.  相似文献   
975.
976.
SARS-CoV-2 is the virus responsible for the COVID-19 pandemic, causing respiratory syndrome and other manifestations. The clinical consequences of the SARS-CoV-2 infection are highly heterogeneous, ranging from asymptomatic and mild to severe and fatal conditions, with the highest mortality rate reached among elderly people. Such heterogeneity appears strongly influenced by the host immune response, which in turn is profoundly affected by aging. In fact, the occurrence of a low-grade inflammation and a decline in specific immune defense is generally reported in older people. Although the low ability of B cells to provide primary and secondary specific responses with a consequent increase in susceptibility to and severity of virus infections is generally described in elderly people, we would like to present here the particular case of a 100-year-old woman, who recovered well from COVID-19 and developed a long-term memory against SARS-CoV-2. Following the infection, the patient’s blood was tested with both a classical ELISA and a specific Cell-ELISA addressed to measure the anti-spike S1 specific IgG released in plasma or produced in vitro by memory B cells, respectively. While showing negative on classical serological testing, the patient’s blood was positive in Cell-ELISA up to 1 year after the infection. Our observation highlights a potential mechanism of B cell-dependent, long-term protection in response to SARS-CoV-2 infection, suggesting that in a case of successful aging, the absence of specific antibodies in serum does not necessarily mean the absence of immune memory.  相似文献   
977.
Objective  Respiratory gated PET/CT (positron emission tomography/computed tomography) of the lung is expected to increase the accuracy of quantitative determinations in lesional activities, regardless of the gating method used; reasonably, respiratory gating should increase standard uptake value (SUV; and possibly decrease lesional size), on the basis of the reduction of the “smearing effect.” However, literature data are very limited, particularly for in vivo studies. The objective of this article is to test the SUV variations in a large group of lung lesion studies. Methods  A group of 26 consecutive positive studies (21 men, 5 women, age 36-84, mean 68), performed on patients referred to our institution for known or suspected lung cancer, are examined. All studies were performed both with conventional PET/CT total body scan and with Real-Time Position Management (RPM) triggered selective gated study of the thorax. Four studies were considered technically unsatisfactory and were discarded; the remaining 22 studies are the object of this work. Max lesional SUVs were evaluated in both settings by semi-automated algorithms; for the gated studies, both values of the bin that showed more relevant variations from the clinical routinary study (“best bin”) and an average value that was calculated over all bins were determined. Results were compared on a one-to-one basis. Results  In conventional, SUV showed a mean ± standard deviation (SD) value of 9.2 ± 6.9 (range 0.9–26). In the averaged gated studies, the mean ± SD value was 13.4 ± 11.7 (range 1.4–47); in the “best bin” dataset the mean ± SD was 14.9 ± 12.9, ranging from 1.6 to 53.1. In general, the use of respiratory trigger induced rather variable but overall consistent increases in SUV. If the percentage variations in the average trigger dataset are considered, there is an average increase of +60%, SD ± 97 (P < 0.05). Similar results are found in the “best bin” dataset, the average percentage increase in SUV values being +77.2% (SD ± 04.6). Conclusions  In lung cancer, triggering procedures increase the signal to noise ratio. The increase in SUV determined by gating is very variable, but generally relevant. This could lead to an SUV values cut-off revision, and may have an impact on smaller lesions detection.  相似文献   
978.
979.
Despite having one of the highest smoking rates among men, information about secondhand smoke (SHS) exposure among Korean adults is lacking. This study describes SHS exposure among Korean men and women. The results were derived from a population-based, cross-sectional telephone survey conducted with 332 adult nonsmokers in Seoul. Sixty-eight percent of nonsmokers were exposed to SHS during a typical day. Exposure was most common in locations other than home and work, where 57% of respondents were exposed, compared to 26% at home and 25% at work. However, among those exposed, the greatest dose of exposure occurred at work (9 cigarettes/day), followed by at home (6 cigarettes/day). Men were more likely to be exposed to SHS at work than women. For men, lack of home smoking bans and strong belief in traditional Korean values were independently associated with SHS exposure in any location. For women, younger age, family members' smoking (non-spouse), and having fewer sources of anti-SHS messages were independently associated with SHS exposure anywhere. The results highlight the need for strong, comprehensive SHS control measures, such as a complete ban of smoking in all workplaces and public places, as well as public health campaigns to promote home smoking bans and non-smoking norms.  相似文献   
980.
CD4(+) helper T cells are critical for protective immune responses and yet suboptimally primed in response to tumors. Cell-based vaccination strategies are under evaluation in clinical trials but limited by the need to derive antigen-presenting cells (APC) from patients or compatible healthy donors. To overcome these limitations, we developed CD4(+) T cell-targeted synthetic microbead-based artificial APC (aAPC) and used them to activate CD4(+) T lymphocytes specific for a tumor-associated model antigen (Ag) directly from the naive repertoire. In vitro, aAPC specifically primed Ag-specific CD4(+) T cells that were activated to express high levels of CD44, produced mainly interleukin 2, and could differentiate into Th1-like or Th2-like cells in combination with polarizing cytokines. I.v. administration of aAPC led to Ag-specific CD4(+) T-cell activation and proliferation in secondary lymphoid organs, conferred partial protection against subcutaneous tumors, and prevented the establishment of lung metastasis. Taken together, our data support the use of cell-free, synthetic aAPC as a specific and versatile alternative to expand peptide-specific CD4(+) T cells in adoptive and active immunotherapy.  相似文献   
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