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排序方式: 共有336条查询结果,搜索用时 15 毫秒
91.
The present study examines the frequency of the two main HFE mutations (C282Y and H63D) in a randomly selected population of 346 individuals including 201 DNA samples from women with cervical neoplasia (including high-grade squamous intraepithelial lesions and invasive squamous cell carcinoma) and a control population of 146 women from the same geographical area. We found a significantly lower risk of development of cervical neoplasia in H63D carriers (OR = 0.56; 95% CI 0.35-0.92; p = 0.01). Multivariate logistic regression analysis confirms this observation (OR = 0.55; 95% CI 0.35-0.88, p = 0.01). Regarding the C282Y mutation no association was found (OR = 1.32; 95% CI 0.53-3.33; p = 0.52). In addition, a significant difference between H63D carrier and non-carrier women on the time-to-onset of cervical lesions was observed (log-rank test: p = 0.0012). These results indicate that HFE could be considered a candidate modifier gene of viral-related neoplasia such as cervical carcinoma possibly by a dual role on iron metabolism and immunological system.  相似文献   
92.
As the most apical structure between epithelial and endothelial cells, tight junctions (TJ) are well known as functioning as a control for the paracellular diffusion of ions and certain molecules. It has however, become increasingly apparent that the TJ has a vital role in maintaining cell to cell integrity and that the loss of cohesion of the structure can lead to invasion and thus metastasis of cancer cells. This article will present data showing how modulation of expression of TJ molecules results in key changes in TJ barrier function leading to the successful metastasis of a number of different cancer types.  相似文献   
93.
S. A. Thiryayi, J. Marshall and D. N. Rana
An audit of liquid‐based cervical cytology screening samples (ThinPrep and SurePath) reported as glandular neoplasia Objectives: The aims of this study were to assess the number of cases diagnosed as glandular neoplasia (national report code 6) of cervical (6A) and non‐cervical (6B) types on ThinPrep (TP) and SurePath (SP) liquid‐based cytology (LBC) samples and to calculate the positive predictive value (PPV) of these diagnoses for significant glandular and/or squamous pathology for local audit and as a contribution to national data on glandular neoplasia. Methods: A computerized search identified all screening LBC samples reported as glandular neoplasia during the 24‐month period from January 2006 to December 2007. Corresponding histology samples were identified, with a minimum follow‐up period of 6 months for each case. Results: A total of 70 samples, representing 70 patients, were reported as glandular neoplasia, 39 TP (55.7%) and 31 SP (44.3%), with 46 samples (31 TP, 15 SP) reported as 6A and 24 samples (eight TP, 16 SP) as 6B. PPV of glandular neoplasia was calculated for a biopsy diagnosis of cervical glandular intraepithelial neoplasia/adenocarcinoma and/or cervical intraepithelial neoplasia (CIN) 2 or worse. The PPV of 6A was 100% for both TP and SP. The PPV of 6B for adenocarcinoma was 62.5% for TP and 66.7% for SP. The combined PPV for 6A + 6B was 92.3% for TP, 83.3% for SP and 88.4% combined. The overall pick‐up rates for the two methods were significantly different (TP 0.031%, SP 0.052%; P = 0.014). Histology showed only CIN3 with endocervical crypt involvement in nine TP cases and one SP case.  相似文献   
94.
E. L. Moss, A. Moran, G. Douce, J. Parkes, R. W. Todd and C. E. W. Redman Cervical cytology/histology discrepancy: a 4‐year review of patient outcome Objective: To investigate the diagnosis, review and management of women identified as having a cytology/histology discrepancy. Methods: A review of all patients diagnosed with a discrepancy between referral smear and cervical histology was performed between January 2003 and December 2004. Cases were followed for a minimum of 4 years and patient management and outcome reviewed. Results: A significant discrepancy was identified in 79 cases, 0.1% of all smears (n = 80 926) analysed during the study period. A discrepancy between cytology and histology, obtained from large loop excision of the transformation zone (LLETZ), was confirmed by multidisciplinary review in 42 cases (53.2%). In 37 cases (46.8%) the cytological and/or histological diagnosis was revised; the cytology was significantly more likely than the histology to be amended (chi square P = 0.005), most often because cytology had been overcalled. Of the confirmed discrepancy cases, 33 (78.6%) were due to high‐grade squamous cell or glandular abnormalities on cytology with a negative, inflammatory or human papillomavirus (HPV) infection on histology (HGC/NH). HGC/NH cases were managed by cytological follow‐up in 29 (87.9%), of which 72.4% of the smears were negative when performed at least 6 months post‐excision. During the 4‐year follow‐up period six women with a confirmed HGC/NH underwent a repeat cervical excision (hysterectomy or LLETZ), and of these, HPV effect was seen in two cases but no cervical intraepithelial neoplasia was detected in any of the histological specimens. Conclusion: Cytology overcall was responsible for the majority of cytology/histology discrepancies. A confirmed discrepancy is not an indication for a further excisional biopsy but follow‐up is essential because a small percentage of patients may have disease that has been missed.  相似文献   
95.
P. K. Wright, J. Marshall and M. Desai Comparison of SurePath ® and ThinPrep ® liquid‐based cervical cytology using positive predictive value, atypical predictive value and total predictive value as performance indicators Objective: Two liquid‐based cytology (LBC) systems are in widespread use in the UK: ThinPrep® and SurePath®. A number of studies have now compared LBC with conventional cytology in cervical screening. However, to date, we are aware of no studies that have compared ThinPrep® with SurePath® LBC. As the selection and use of specific diagnostic systems in a laboratory has significant clinical and economic implications, there is a clear need to compare directly existing LBC technology. The objective of this study was to compare ThinPrep® with SurePath® LBC in a single cytology laboratory using performance indicators. Methods: Data were collected for all cervical cytology samples processed at Manchester Cytology Centre over a 1‐year period. ThinPrep® LBC was compared with SurePath® LBC using positive predictive value (PPV), atypical predictive value (APV) and total predictive value (TPV), reflecting outcome of cervical intraepithelial neoplasia (CIN) grade 2 or worse for high‐grade dyskaryosis (PPV), low‐grade dyskaryosis or borderline (atypical) cytology (APV) and all (total) abnormal cytology (TPV). Results: 2287 (out of 56 467) (ThinPrep®) and 586 (out of 22 824) (SurePath®) samples showed borderline or worse cytology after exclusion criteria. PPV, APV and TPV were within acceptable ranges for both ThinPrep® and SurePath®. Conclusions: ThinPrep® and SurePath® were equivalent based on three performance indicators. We suggest that APV and TPV should be used as an adjunct to PPV and other methods of quality assurance for cervical screening.  相似文献   
96.
Background An adult male owl monkey (Aotus nancymae) underwent a splenectomy. When the spleen was removed, a small, nodular mass slightly bulging over the splenic surface was noted. Methods The mass was examined by light and transmission electron microscopy and by immunohistochemistry. Results On light microscopy, the mass was well‐circumscribed, non‐encapsulated, and composed of haphazardly arranged smooth muscle bundles admixed with numerous small capillary‐like structures containing blood. Immunohistochemical (IHC) staining revealed the tumor was strongly positive for smooth muscle actin yielding vascular smooth muscle bundles, and for Factor VIII, staining endothelial cells within the smooth muscle bundles. Transmission electron microscopy (TEM) showed a large portion of the cells to be atypical appearing smooth muscle and a few cells had structures resembling Weibel–Palade bodies indicating endothelial cells. Conclusions Based on cell morphology, by light and TEM, and IHC a final diagnosis of splenic angioleiomyoma was made. This is, to our knowledge, the first report of an angioleiomyoma in a non‐human primate.  相似文献   
97.
Previous studies have demonstrated that the Hedgehog (Hh) signaling pathway plays a critical role in the development and patterning of many endodermally derived tissues. We have investigated the role of Sonic hedgehog (Shh) in formation of the prostate gland by examining the urogenital phenotype of Shh mutant fetuses. Consistent with earlier work reporting an essential role for Shh in prostate induction, we have found that Shh mutant fetuses display abnormal urogenital development and fail to form prostate buds. Unexpectedly, however, we have discovered that this prostate defect could be rescued by three different methods: renal grafting, explant culture in the presence of androgens, and administration of dihydrotestosterone (DHT) to pregnant mice, indicating that the prostate defect in Shh mutants is due to insufficient levels of androgens. Furthermore, we find that the inhibition of Hh pathway signaling by treatment with cyclopamine does not block prostate formation in explant culture, but instead produces morphological defects consistent with a role for Hh signaling in ductal patterning. Taken together, our studies indicate that the initial organogenesis of the prostate proceeds independently of Shh, but that Shh or other Hh ligands may play a role in subsequent events that pattern the prostate.  相似文献   
98.
OBJECTIVE: The National Health Service Cervical Screening Programme monitors the quality of colposcopy services through the annual KC65 returns. The 2002 returns demonstrated that Standard 7c, which specifies a biopsy rate > or = 90% at first colposcopy visit for high-grade referrals, was not met in the assessed 3-month period. This was investigated along with the other standards. METHODS: Retrospective colposcopy records were accessed for the 597 new referrals, excluding 10 pregnant patients, seen at the colposcopy clinic at the Royal Victoria Infirmary between 1 July 2001 and 31 December 2002, following an abnormal high-grade smear. Cytology and histopathology computer records were checked for confirmation. The results were assessed against the colposcopy standards applicable at that time and the revised standards (2004). RESULTS: Biopsies were taken from 94.47% (Standard > or = 90%) of women at index colposcopy visit including wire loop excision biopsies from 66.16% (87.97% of high-grade colposcopic appearances). Cervical intraepithelial neoplasia (CIN) on histology was found in 91.79% in the study group (Standard > or = 85%) and in 96.71% of index visit biopsies (Standard > or = 90%), meeting the applicable colposcopy standards. The revised 2004 standards specify a biopsy in > or = 95% of high-grade referrals and excision biopsies in 95% if colposcopic appearances are also high-grade, if colposcopy is low grade but the smear is severely dyskaryotic, or when the lesion extends into the canal. The positive predictive value of high-grade cytology for this entire group was 75.54% with CIN present in 90.95%. CONCLUSION: From this study it appears that high-grade cytology in this centre reliably indicates high-grade CIN. Therefore, in women referred for colposcopy following a high-grade smear, excision biopsies should be performed in a higher proportion at the first visit to comply with the revised standards.  相似文献   
99.
Hypotonically activated chloride current in HSG cells   总被引:6,自引:0,他引:6  
Hypotonically induced changes in whole-cell currents and in cell volume were studied in the HSG cloned cell line using the whole-cell, patch clamp and Coulter counter techniques, respectively. Exposures to 10 to 50% hypotonic solutions induced dose-dependent increases in whole-cell conductances when measured using K+ and Cl containing solutions. An outward current detected at 0 mV, corresponded to a K+ current which was transiently activated, (usually preceding activation of an inward current and had several characteristics in common with a Ca2+-activated K+ current we previously described in these cells. The hypotonically induced inward current had characteristics of a Cl current. This current was inhibited by NPPB (5-nitro-2-(3-phenyl-propylamino)-benzoate) and SITS (4-acetamido-4-isothiocyanostilbene), and its reversal potentials corresponded to the Cl equilibrium potentials at high and low external Cl concentrations. The induced current inactivated at voltages greater than +80 mV, and the I-V curve was outwardly rectifying. The current was unaffected by addition of BAPTA or removal of GTP from the patch pipette, but was inhibited by removal of ATP or by the presence of extracellular arachidonic acid, quinacrine, nordihydroguairetic acid, and cytochalasin D. Moreover, exposure of HSG cells to hypotonic media caused them to swell and then to undergo a regulatory volume decrease (RVD) response. Neither NPPB, SITS or quinine acting alone could inhibit RVD, but NPPB and quinine together totally inhibited RVD. These properties, plus the magnitudes of the induced currents, indicate that the hypotonically induced K+ and Cl currents may underlie the RVD response. Cytochalasin D also blocked the RVD response, indicating that intact cytoskeletal F-actin may be required for activation of the present currents. Hence, our results indicate that hypotonic stress activates K+ and Cl conductances in these cells, and that the activation pathway for the K+ conductance apparently involves [Ca2+], while the activation pathway for the Cl conductance does not involve [Ca2+] nor lipoxygenase metabolism, but does require intact cytoskeletal F-actin.We thank Mr. Louis Stamps for excellent technical support. Thanks also to Dr. Mitsunobu Sato from the Second Department of Oral and Maxillofacial Surgery, Tokushima University, Japan for sending us the HSG-PA cells, and to Dr. Englert from Hoechst company for providing us with NPPB. This work was supported by National Institute of Dental Research grants R01 DE09812 and R03 DE10535.  相似文献   
100.
In addition to an intrathymic pathway of T-cell differentiation, extrathymic pathways of T-cell differentiation have recently been demonstrated to occur in multiple sites in mice. Such sites include the sinusoids of the liver, the intraepithelial region of the intestine, and the omentum of the peritoneal cavity. Although these extrathymic pathways are minimal at a young age, they become predominant with aging. Extrathymically differentiated T cells display many properties distinct from those of regular T cells of thymic origin. For instance, they consist of a considerably large proportion of γδT cells as well as αβT cells, contain double-negative CD4CD8 cells and self-reactive oligoclones, constitutively express the II-2 receptor β-chain, and have an αα homodimer of CD8 if they carry it. Cumulative evidence reveals that the extrathymic pathways comprise a primitive and fundamental immune system in the body and play a pivotal role in immune reactions under conditions of aging, bacterial infections, malignancies, autoimmune diseases, and pregnancy.  相似文献   
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