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991.
This study investigated regional variations in the contribution made by different human papilloma (HPV) types to invasive cervical cancer (ICC). A total of 85 studies using polymerase chain reaction to estimate HPV prevalence in ICC were identified. Data on HPV prevalence were extracted separately for squamous cell carcinoma (SCC) and for adeno- and adenosquamous-carcinoma (ADC). A total of 10 058 cases (8550 SCC, 1508 ADC) were included in pooled analyses. The most common HPV types in ICC were, in order of decreasing prevalence, HPV16, 18, 45, 31, 33, 58, 52, 35, 59, 56, 6, 51, 68, 39, 82, 73, 66 and 70. In SCC, HPV16 was the predominant type (46-63%) followed by HPV18 (10-14%), 45 (2-8%), 31 (2-7%) and 33 (3-5%) in all regions except Asia, where HPV types 58 (6%) and 52 (4%) were more frequently identified. In ADC, HPV prevalence was significantly lower (76.4%) than in SCC (87.3%), and HPV18 was the predominant type in every region (37-41%), followed by 16 (26-36%) and 45 (5-7%). The overall detection of HPV DNA was similar in different regions (83-89%). A majority of ICC was associated with HPV16 or 18 in all regions, but approximately a quarter of all ICC cases were associated with one of 16 other HPV types, their distribution varying by region.  相似文献   
992.
The influence of body mass index (BMI) on oral cancer risk was evaluated in 375 incident cases and 375 age-gender-matched hospital-based controls. Low BMIs at diagnosis and 2 years before diagnosis were associated with significantly elevated odds ratios (OR for BMI < or =22 vs >26 kg m(-2); 3.64; 95% confidence interval, CI: 2.27-5.82 and 3.31; 95% CI: 2.04-5.39, respectively). The association with low BMI, however, tended to be weaker and nonsignificant among never smokers and never drinkers.  相似文献   
993.
To evaluate the role of human papillomavirus (HPV) and other risk factors in the aetiology of invasive cervical carcinoma (ICC), we conducted a hospital-based case-control study in Chennai, Southern India. A total of 205 ICC cases (including 12 adenocarcinomas) and 213 frequency age-matched control women were included. HPV DNA in cervical cells was evaluated by means of a polymerase chain-reaction assay. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were computed by means of unconditional multiple logistic regression models. HPV infection was detected in all but one ICC cases and in 27.7% of control women (OR = 498). Twenty-three different HPV types were found. HPV 16 was the most common type in either cases or controls, followed by HPV 18 and 33. The association of ICC with HPV 18 and HPV 16-associated types was somewhat stronger than the one with HPV 16. Multiple HPV infections did not show a higher OR for ICC than single infections. Other than HPV infection, high parity (OR for >4 vs. /=45 years = 4.2) were significantly associated with ICC, also after restricting the analysis to HPV-positive cases and controls. Poor hygienic conditions were associated with an increased risk of HPV infection among control women but not with ICC risk among HPV-positive women. A vaccine against HPV 16 and 18 may be effective in more than three-quarters of ICC in the study area.  相似文献   
994.
Human papillomavirus infection among women in South and North Vietnam   总被引:10,自引:0,他引:10  
The incidence rate of invasive cervical carcinoma (ICC) is 4-fold higher in Ho Chi Minh City, in the South of Vietnam, than in Hanoi, in the North. Thus, we explored the prevalence of and the risk factors for human papillomavirus (HPV) infection in these 2 areas. A population-based random sample of married women aged 15-69 years were interviewed and had a gynaecological examination in the urban district of Ho Chi Minh City and in a peri-urban district in Hanoi. HPV DNA detection was performed using a GP5+/6+ primer-mediated PCR enzyme immunoassay. A total of 922 women from Ho Chi Minh and 994 from Hanoi, for whom a Pap smear and HPV-status were available, were evaluated. HPV DNA was detected among 10.9% of women in Ho Chi Minh City and 2.0% in Hanoi (age standardized prevalence, world standard population: 10.6% and 2.3%, respectively). In the 2 areas combined, 30 different HPV types were found, the most common being HPV 16 (in 14 single and 18 multiple infections), followed by HPV 58, 18 and 56. A peak of HPV DNA detection in women younger than age 25 was found in Ho Chi Minh City (22.3%) but not in Hanoi. Major risk factors for HPV DNA detection were indicators of sexual habits, most notably the presence of HSV-2 antibodies, nulliparity and the current use of oral contraceptives. Women in Hanoi showed the lowest HPV prevalence ever reported so far, suggesting that HPV has not spread widely in this population. As expected, HPV prevalence in a population seemed to be closely correlated with ICC incidence rates.  相似文献   
995.
Screening and assessment for single and discrete sensory systems, such as screening for tactile defensiveness, can provide valid information for identifying sensory processing dysfunction of children. Tactile defensiveness may be considered to be a specialized type of what was previously called a sensory integrative disorder and now is termed a sensory modulation disorder. The current study was designed to examine further the phenomenon of tactile defensiveness, particularly the stability of the concept, across different cultures. In this study, the test scores of 28 European children (16 girls and 12 boys of three different nationalities) on the Touch Inventory for Elementary School Aged Children (TIE) were collected and analysed (Royeen and Fortune, 1990). The TIE scores of the European sample were compared with that of the American sample in the original TIE study (Royeen and Fortune, 1990). Results revealed that the mean test scores on the TIE between the American sample and European sample were very similar (n = 415, M = 41.0 vs. n = 28, M = 39.5) and no significant difference was found between the two samples (t = 0.99, p < 0.05). Internal consistency of the TIE on the European sample was found to be good and close to that obtained from the American sample (0.78 vs. 0.89). The current study provides evidence that tactile defensiveness is a stable phenomenon across different cultures as measured by the TIE. Limitations of the study include use of a small and convenient sample of European children. Further studies are recommended to examine tactile defensiveness as a clinical phenomenon.  相似文献   
996.
Mu L  Feng SS 《Pharmaceutical research》2003,20(11):1864-1872
PURPOSE: We successfully manufactured nanoparticles of biodegradable polymers for controlled release of paclitaxel. TPGS (d-alpha-tocopheryl polyethylene glycol 1000 succinate) could be a novel material to make nanoparticles of high drug encapsulation efficiency (EE) and desired physicochemical and pharmaceutical properties of the drug loaded nanoparticles. Among various controlling parameters in the process, the present work is to elucidate the effects of the surfactant stabilizer and the drug loading ratio. METHODS: Paclitaxel loaded PLGA nanoparticles were formulated at various drug-loading ratios by a modified single emulsion solvent extraction/evaporation technique. TPGS was introduced either as the emulsifier or as a matrix material component by using different technique. Polyvinyl alcohol (PVA) was also used for a comparison. The nanoparticles of various recipes were characterized by various state-of-the-art instrument technology for their properties. RESULTS: The EE and the in vitro release behavior were found significantly influenced by the drug loading ratio and the surfactant stabilizer encountered. TPGS involved nanoparticles can have high EE and other favorable properties. CONCLUSIONS: TPGS could be a novel and effective emulsifier, which can result in high EE and desired properties of paclitaxel-loaded polymeric nanoparticles.  相似文献   
997.
A comparison between two-dimensional (2D), and three-dimensional (3D) ultrasonography was made in four fetuses diagnosed with neural tube defect (NTD) in the first half of pregnancy. 3D ultrasonography (orthogonal and multiplanar systems) proved to be an excellent complement to 2D, particularly when using orthogonal planes. When using the 3D multiplanar surface imaging system, excellent images of the malformations can be rapidly obtained.  相似文献   
998.
999.
We present the results of an immunohistochemical study aimed at localizing the neuropeptide Y (NPY) in the brain of the Senegalese sole, Solea senegalensis, using an antiserum raised against porcine NPY and the streptavidin-biotin-peroxidase method. In this species, we have identified immunoreactive cells in the ventral and dorsal telencephalon, caudal preoptic area, ventrocaudal hypothalamus, optic tectum, torus longitudinalis, synencephalon and isthmic region. NPY-immunoreactive fibers were profusely distributed throughout the brain, also reaching the adenohypophysis. The extensive distribution of NPY suggests an important role for this neuropeptide in a variety of physiological processes, including the neuroendocrine control of adenohypophyseal functions. Our results are compared with those obtained in other teleosts and discussed in relation to putative functions of NPY in the control of metabolism and reproduction in the Senegalese sole.  相似文献   
1000.
The kinetics of the gB-specific and neutralizing antibody responses to human cytomegalovirus (HCMV) were analyzed in 26 allogeneic stem-cell transplant recipients who either did (n = 20) or did not (n = 6) develop asymptomatic HCMV active infection during the study period. Antibody response profiles varied widely among individuals in both groups, irrespective of whether HCMV active infection did or did not occur. Development of HCMV active infection was not preceded by a decline in functional serum antibody levels. Neither the absence nor the presence of HCMV active infection correlated with either high or low serum levels of gB-specific and neutralizing antibodies, respectively. In most patients, episodes of HCMV replication were not followed by a marked increment in functional serum antibody titers. Therefore, resolution of an ongoing HCMV active infection was not associated with a vigorous antibody response to viral replication. In addition, this study supports previous data indicating that passive transfer of human immunoglobulins may result in an increment in gB-specific and neutralizing serum antibody levels, the magnitude of which varies among recipients; however, both patients with and without measurable increments in serum antibody levels developed HCMV active infections with comparable frequency.  相似文献   
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