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11.
OBJECTIVES: To assess visual inspection with acetic acid (VIA) as a screening tool for use in a well-equipped health center in Peru, to evaluate VIA as an alternative or adjunct to the Papanicolaou (Pap) smear, and to determine if VIA can play a role in settings other than low-resource ones. METHODS: This was a prospective study of 1 921 asymptomatic women living in Lima, Peru, carried out in 1999 and 2000. The study was performed at a cancer center equipped with the latest-generation technology and highly trained oncologists. The women underwent a complete clinical evaluation, including a Pap smear and VIA. Participants with any positive test were referred for colposcopy and biopsy. RESULTS: More women tested positive by VIA than on the Pap smear (6.9% vs. 4.2%; P = 0.0001). There were 35 women with histologic cervical intraepithelial neoplasia grade 1 (CIN 1); of these, 15 were detected by Pap and 20 by VIA (P = 0.4). A diagnosis of CIN 2 or 3 (CIN 2-3) was confirmed in a total of 13 cases; Pap detected 5 of the cases and VIA 11 of the cases (P = 0.06). The positive predictive value for detection of CIN 2+ was 8.3% for VIA and 6.3% for Pap (P = 0.5). Most importantly, while only 2.3% of patients with a positive VIA were lost to follow-up before colposcopy, that was true for 26.3% of the women with a positive Pap smear (P < 0.0001). CONCLUSIONS: VIA is useful for detection of precursor lesions of cervical cancer not only in low-resource settings but also in well-equipped health centers and cancer centers. In these non-low-resource settings, VIA has a positive predictive value comparable to the conventional Pap smear, but it is more likely to achieve earlier diagnosis, follow-up, and treatment than cytology-based screening.  相似文献   
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The fluorescence spectral fingerprint, also known as the excitation-emission matrix (EEM), is used to assess and visualize therapeutic drug photodegradation in combination with chemometrics. Examination of EEM-parallel factor analysis (PARAFAC) data showed that an individual component was easily separated from a mixture of photogenerated products of a heterocyclic pharmacophore, in this case, phenothiazine drugs (PTZs). Detailed investigations of both structure–EEM relationships and kinetics revealed that the components extracted from EEM–PARAFAC could be quantitatively attributed to such photogenerated products as phenothiazine sulfoxide and carbazole derivatives. EEM in combination with principal component analysis (PCA) could be used as a mapping tool to visualize information of the photodegradation process of PTZs. We also assessed the photostability of various types of PTZs containing side chains by using validated EEM–PARAFAC methodology.

Drug quality and assurance changes with time under the influence of a variety of environmental factors, such as light, temperature, and moisture.  相似文献   
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Scrub typhus has struck back, albeit with renewed vigour, impacting areas with previously known endemicity as also impressing newer expanses. It is not surprising, therefore, that Scrub typhus has emerged as a leading cause of public health concern globally as well as in India, but are we ready to take on the challenge?Over the last decade, there has been a global increase in the number of outbreaks of Scrub typhus, be it the military occupied areas or the civil population at large. The innumerable outbreaks of Scrub typhus, although disconcerting, have nonetheless contributed phenomenally towards better understanding of the dynamics of scrub typhus. There have been significant contributions to awareness of the disease amongst medical professionals, scrub typhus as a cause of Acute Undifferentiated Febrile Illness (AUFI) and newer clinical manifestation – Acute Encephalitis Syndrome (AES), availability and advances in diagnostics and management, man-vector-pathogen interactions, new records of Leptotrombidium species, newer vectors and Orientia species.Antigenic diversity and the varied clinical presentation of scrub typhus, absence of scrub typhus surveillance system and a lack of political will to recognize the disease as one of the important reemerging public health problem are areas seeking concerted deliberations and actions so that the challenges posed by scrub typhus can be addressed.  相似文献   
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Although the mortality rates of gastric cancer (GC) are gradually declining, gastric cancer is still the fourth leading cause of cancer-related death worldwide. This may be due to the high rate of patients who are diagnosed with GC at advanced stages. However, in countries such as Japan with endoscopic screening systems, more than half of GCs are discovered at an early stage, enabling endoscopic resection (ER). Especially after the introduction of endoscopic submucosal dissection (ESD) in Japan around 2000, a high en bloc resection rate allowing pathological assessment of margin and depth has become possible. While ER is a diagnostic method of treatment and may not always be curative, it is widely accepted as standard treatment because it is less invasive than surgery and can provide an accurate diagnosis for deciding whether additional surgery is necessary. The curability of ER is currently assessed by the completeness of primary tumor removal and the possibility of lymph node metastasis. This review introduces methods, indications, and curability criteria for ER of EGC. Despite recent advances, several problems remain unsolved. This review will also outline the latest evidence concerning future issues.  相似文献   
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Here, we show that AU-1, spirostanol saponin isolated from Agavaceae plants, causes a transient increase in cyclin-dependent kinase inhibitor (CDKI) p21/Cip1 through the upregulation of miRNAs, miR-34 and miR-21. AU-1 stimulated p21/Cip1 expression without exerting cytotoxicity against different types of carcinoma cell lines. In renal adenocarcinoma ACHN cells, AU-1 transiently elevated the expression level of p21/Cip1 protein without marked increases in p21/Cip1 mRNA levels. Rapid and transient increases in miR-34 and miR-21, both of which are known to upregulate p21/Cip1, were observed in AU-1-treated cells. Inhibitor for miR-34 and for miR-21 significantly blocked the AU-1-caused increase in p21/Cip1, indicating that elevation of p21/Cip1 protein by AU-1 is dependent on these microRNAs. We further clarified that NAD-dependent deacetylase SIRT1, a direct target of miR-34, is decreased by the treatment with AU-1. Furthermore, we found that SIRT1-knockdown increases p21/Cip1 protein levels in an miR-21-dependent manner. On the other hand, ectopic expression of p21/Cip1 resulted in the lowered expression of miR-34 and miR-21, suggesting that reciprocal regulation exists between p21/Cip1 and these miRNAs. We propose that the following feedback network composed of miR-34/SIRT1/miR-21/p21 is triggered by the treatment with AU-1: in cells treated with AU-1, transient elevation of miR-34 leads to the downregulation of SIRT1, thereby miR-21 is freed from SIRT1-dependent suppression. Then, elevated miR-21 upregulates p21/Cip1 protein, followed by the suppression of miR-34 expression.  相似文献   
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This study investigated issues related to initial stability after stem fixation. Finite element models of the AI-Hip cementless stem were constructed for computer simulation.  相似文献   
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Sickle cell disease is characterized by chronic hemolytic anemia and vaso-occlusive painful crisis. The vascular occlusion in sickle cell disease is a complex process and accounts for the majority of the clinical manifestations of the disease. Abdominal pain is an important component of vaso-occlusive painful crisis and may mimic diseases such as acute appendicitis and cholecystitis. Acute pancreatitis is rarely included as a cause of abdominal pain in patients with sickle cell disease. When it occurs it may result form biliary obstruction, but in other instances it might be a consequence of microvessel occlusion causing ischemia. In this series we describe four cases of acute pancreatitis in patients with sickle cell disease apparently due to microvascular occlusion and ischemic injury to the pancreas. All patients responded to conservative management. Acute pancreatitis should be considered in the differential diagnosis of abdominal pain in patients with sickle cell disease.  相似文献   
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