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Background and study aimsThe aim of this study was to determine the pattern of histologically-proven gastric cancer in Eastern Libya and explore its association with Helicobacter pylori infection.Patients and methodsThe registries of the Departments of Histopathology, Faculty of Medicine, Benghazi University and Oncology, Al-Jomhoria Hospital, Benghazi, were reviewed for cases with primary gastrointestinal cancer from January 2000 to December 2002 (sole Histopathology and Oncology Departments in Eastern Libya). Slides of hematoxylin and eosin stain of gastric cancer patients were re-stained to detect H. pylori. The American Joint Committee on Cancer Tumor, Node, Metastasis staging was used for clinical and pathologic staging. Gastric cancer biopsy materials were classified into intestinal or diffuse type according to Lauren criteria.ResultsOne hundred and fourteen cases of gastric cancer were diagnosed. Tumor stages were: 2 (14%), 3 (21%), 4 (57%) and unknown (8%). Most common site of involvement was the antrum (48%). Diffuse adenocarcinoma occurred in 56 patients (49.1%), intestinal adenocarcinoma in 46 (40.4%) and malignant gastric lymphoma in 12 (10.5%). The overall frequency of H. pylori infection was 63.2% (72/114), more frequent in intestinal adenocarcinoma (71.7%) and malignant lymphoma (66.6%) than diffuse adenocarcinoma (55.3%). The frequency of gastric cancer increased throughout the three years of study.ConclusionThe majority of the patients were diagnosed in locally advanced or metastatic stage. Clearly more efforts need to be given to early detection. We showed a stronger association of H. pylori infection with intestinal type gastric adenocarcinoma and malignant lymphoma than diffuse adenocarcinoma suggesting that H. pylori infection is the most probable causal factor of gastric cancer in this part of Libya.  相似文献   
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Traditional histology relies on processing and physically sectioning either frozen or formalin‐fixed paraffin‐embedded (FFPE) tissue into thin slices (typically 4‐6 μm) prior to staining and viewing on a standard wide‐field microscope. Microscopy using ultraviolet (UV) surface excitation (MUSE) represents a novel alternative microscopy method that works with UV excitation using oblique cis‐illumination, which can generate high‐quality images from the cut surface of fresh or fixed tissue after brief staining, with no requirement for fixation, embedding and histological sectioning of tissue specimens. We examined its potential utility in dermatopathology. Concordance between MUSE images and hematoxylin and eosin (H&E) slides was assessed by the scoring of MUSE images on their suitability for identifying 10 selected epidermal and dermal structures obtained from minimally fixed tissue, including stratum corneum, stratum granulosum, stratum spinosum, stratum basale, nerve, vasculature, collagen and elastin, sweat glands, adipose tissue and inflammatory cells, as well as 4 cases of basal cell carcinoma and 1 case of pseudoxanthoma elasticum deparaffinized out of histology blocks. Our results indicate that MUSE can identify nearly all normal skin structures seen on routine H&E as well as some histopathologic features, and appears promising as a fast, reliable and cost‐effective diagnostic approach in dermatopathology.  相似文献   
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Background: Glyphosate (GLY) is the most heavily used herbicide in the world. Despite nearly ubiquitous exposure, few studies have examined prenatal GLY exposure and potentially adverse pregnancy outcomes. Preterm birth (PTB) is a risk factor for neonatal mortality and adverse health effects in childhood.Objectives: We examined prenatal exposure to GLY and a highly persistent environmental degradate of GLY, aminomethylphosphonic acid (AMPA), and odds of PTB in a nested case–control study within the ongoing Puerto Rico Testsite for Exploring Contamination Threats (PROTECT) pregnancy cohort in northern Puerto Rico.Methods: GLY and AMPA in urine samples collected at 18±2 (Visit 1) and 26±2 (Visit 3) wk gestation (53 cases/194 randomly selected controls) were measured using gas chromatography tandem mass spectrometry. Multivariable logistic regression was used to estimate associations with PTB (delivery <37wk completed gestation).Results: Detection rates in controls were 77.4% and 77.5% for GLY and 52.8% and 47.7% for AMPA, and geometric means (geometric standard deviations) were 0.44 (2.50) and 0.41 (2.56)μg/L for GLY and 0.25 (3.06) and 0.20 (2.87)μg/L for AMPA, for Visits 1 and 3, respectively. PTB was significantly associated with specific gravity–corrected urinary GLY and AMPA at Visit 3, whereas associations with levels at Visit 1 and the Visits 1–3 average were largely null or inconsistent. Adjusted odds ratios (ORs) for an interquartile range increase in exposure at Visit 3 were 1.35 (95% CI: 0.99, 1.83) and 1.67 (95% CI: 1.26, 2.20) for GLY and AMPA, respectively. ORs for Visit 1 and the visit average were closer to the null.Discussion: Urine GLY and AMPA levels in samples collected near the 26th week of pregnancy were associated with increased odds of PTB in this modestly sized nested case–control study. Given the widespread use of GLY, multiple potential sources of AMPA, and AMPA’s persistence in the environment, as well as the potential for long-term adverse health effects in preterm infants, further investigation in other populations is warranted. https://doi.org/10.1289/EHP7295  相似文献   
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