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981.
982.
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   
983.
984.
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   
985.
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   
986.
The objective of this study was to analyze the possible correlation between Shamblins classification and post-surgical morbidity in the treatment of carotid body tumors (CBTs). Seventy-two patients with carotid body tumors were seen over a 22-year period. Twenty-three patients were excluded as they did not comply with the criteria of the objectives. All patients were grouped according to Shamblins classification. We propose a modification to this classification and make a comparison by analyzing the surgical time and bleeding, as well as the neurological and vascular damage. We resected 50 CBTs in 49 patients, ranging in age from 18 to 73 years. Three groups were formed: group I with 8 (16%) patients, group II with 17 (34%) and group III with 24 (49%). Post-surgical neurological damage was observed in one patient (12.5%) from group I, in six (35%) from group II and in nine patients (37.5%) from group III. Vascular sacrifice had to be performed in 21% of class II tumors and in 8.7% of class III. None of the class I tumors required vascular sacrifice. No statistically significant difference existed for vascular or neurological risk in relation to Shamblins classification. However, when analyzed according to the classification proposed herein, there was a correlation between Shamblins classification and vascular sacrifice ( P =0.001). There was a statistically significant correlation between the original Shamblin and the modified Shamblin regarding surgical time and bleeding. Shamblins classification predicts only vascular morbidity. Neurological morbidity is not reflected in it and only reflects the surgeons experience with CBT resections. Surgical time and bleeding are directly related to the Shamblin as it reflects the size of tumors in relation to the blood vessels. Shamblins classification must be modified to be more objective so that the international reports can accurately reflect the morbidity related to it.  相似文献   
987.
Small size at birth has long been recognized as a factor increasing neonatal morbidity and mortality. During the last decade, reduced growth in early life has also been strongly linked with a number of endocrine dysfunctions. Included among the most important alterations are insulin insensitivity, gonadal and somatotropic axis abnormalities and premature adrenarche. These have been associated with an escalating prevalence of T2DM and CHD abnormal gonads and genitalia, growth hormone resistance and decreased growth as well as early puberty. The usual hypothesis proposed to explain the development of these long term alterations relates to the thrifty phenotype as an adaptive response to in utero malnutrition and modifications thereof; called "Fetal Origins" and updated to "Developmental Origins" which include the additional contributions of the patterns of growth in infancy and childhood. In this paper the factors that participate in the programming of the fetus and infants that lead to endocrine dysfunction in postnatal life is reviewed.  相似文献   
988.
989.
990.

Objective

To study the prevalence of low-risk and high-risk HPV genotypes in a largely suburban, non-Hispanic, white female population of the USA, and to determine the positive predictive value of one-occasion HPV detection and genotyping using high-grade squamous intraepithelial lesion (HSIL) cytology as the endpoint for clinical evaluation.

Methods

HPV DNA present in liquid-based cytology specimens collected by gynecologists in private practice was amplified using nested polymerase chain reaction. HPV DNA was validated by signature DNA sequencing for accurate genotyping.

Results

Of 2633 specimens, 278 were positive for HPV DNA of any genotype. Among 255 single HPV infections, the most prevalent genotype was HPV-16 (n = 50; 19.6%), followed by HPV-52 (n = 24; 9.4%). Only 10 specimens, all positive for a high-risk HPV, were associated with an HSIL cytology result. Among them were 6 of the 50 specimens (12%) tested positive for HPV-16. One novel HPV-39 variant was detected in repeat testing in a patient with persistent HPV infection.

Conclusion

DNA sequencing is a useful method for increasing the specificity of HPV genotyping as an aid to follow persistent high-risk HPV infections to reduce excessive colposcopies in populations with low cancer prevalence.  相似文献   
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