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351.
OBJECTIVE: To assess the predictive value of preoperative endometrial sonography in the diagnosis and surgical treatment of women with amenorrhea due to severe Asherman's syndrome. DESIGN: Patient series. SETTING: Academic clinical practice. PATIENTS: Seven women with severe Asherman's syndrome characterized by amenorrhea despite normal ovulatory function and complete obstruction of the uterine cavity at the level of the cervix or lower uterine segment at hysterosalpingogram. MAIN OUTCOME: Ability of vaginal sonography to predict successful hysteroscopic treatment as assessed by resumption of menstrual cyclicity and normalization of the uterine cavity. RESULTS: Transvaginal sonography demonstrated a well-developed endometrial stripe in three of seven women, while three others had virtually no endometrium seen. All women with well-developed endometrium were found to have adhesions occluding the lower uterine segment and had resumption of normal menses and normalization of the cavity after hysteroscopy. The women with minimal endometrium had no cavity identified and derived no benefit from surgery. A seventh woman with endometrium seen only on one side of the cavity had patency successfully established only on that side. CONCLUSION: The endometrial pattern seen with transvaginal sonography is highly predictive of surgical and clinical outcome in women with severe Asherman's syndrome characterized by complete obstruction of the cavity at hysterosalpingogram. 相似文献
352.
Matthew Hurst 《International Journal on Document Analysis and Recognition》2006,8(2-3):123-131
Tables appearing in natural language documents provide a compact method for presenting relational information in an immediate and intuitive manner, while simultaneously organizing and indexing that information. Despite their ubiquity and obvious utility, tables have not received the same level of formal characterization enjoyed by sentential text. Rather, they are modeled in terms of geometry, simple hierarchies of strings and database-like relational structures. Tables have been the focus of a large volume of research in the document image analysis field and lately, have received particular attention from researchers interested in extracting information from non-trivial elements of web pages. This paper provides a framework for representing tables at both the semantic and structural levels. It presents a representation of the indexing structures present in tables and the relationship between these structures and the underlying categories.
Matthew Hurst graduated from Edinburgh University in 1992 and completed an MPhil at Cambridge in Computer Speech and Language Processing. He then worked at The University of Edinburgh on a number of projects involving text and document analysis before enroling in the PhD programme. While studying for his PhD, he completed a European Science and Technology Fellowship in Japan. After working for IBM Research, Tokyo he moved tothe United States of America to work for a number of companies with unique applications utilizing applied natural language processing and document analysis. He is currently the Director of Science and Innovation at Nielsen BuzzMetrics. 相似文献
353.
Standard Reference Materials SRMs 2241 through 2243 are certified spectroscopic standards intended for the correction of the relative intensity of Raman spectra obtained with instruments employing laser excitation wavelengths of 785 nm, 532 nm, or 488 nm/514.5 nm. These SRMs each consist of an optical glass that emits a broadband luminescence spectrum when illuminated with the Raman excitation laser. The shape of the luminescence spectrum is described by a polynomial expression that relates the relative spectral intensity to the Raman shift with units in wavenumber (cm(-1)). This polynomial, together with a measurement of the luminescence spectrum of the standard, can be used to determine the spectral intensity-response correction, which is unique to each Raman system. The resulting instrument intensity-response correction may then be used to obtain Raman spectra that are corrected for a number of, but not all, instrument-dependent artifacts. Peak area ratios of the intensity-corrected Raman spectrum of cyclohexane are presented as an example of a methodology to validate the spectral intensity calibration process and to illustrate variations that can occur in this measurement. 相似文献
354.
Toxicity characterisation of organic contaminants in stormwaters from an agricultural headwater stream in south east England 总被引:5,自引:0,他引:5
The transient movement of pesticides at biologically active concentrations during storm events is considered to be a cause of biological impoverishment in some headwater streams. The programme of work described sought to identify compounds that are the cause of toxic effects during such events. Along with targeted pesticide analysis, toxicity identification evaluation (TIE) procedures were used to identify compounds with a demonstrated toxic effect. These procedures were specifically directed towards isolating and attributing toxicity to classes of organic contaminants in samples collected from an English headwater stream during a storm event. The organic load was isolated by means of solid-phase extraction (SPE). Bioassay of the SPE extract at x 100 whole water concentrations confirmed that the samples contained substances toxic to Daphnia magna, although the raw samples were not toxic. Targeted pesticide analysis identified simazine and diuron as the major pesticides present and, using a toxicity unit (TU) approach. were shown to be responsible for a significant amount of the observed concentrate toxicity during a runoff event. However, they were not present in sufficient quantities to be totally responsible for a more toxic later event. By simplification of the SPE isolate using reverse-phase HPLC, fractions from which were tested for toxicity, the cause of concentrate toxicity in the later event was isolated to two discrete fractions. GC-MS analysis of these fractions identified nonylphenol. endosulfan sulphate and pendimethalin as present, with the majority of toxicity attributed to nonylphenol (NP). The main advantage of the TIE approach is that it allows biological active compounds with a demonstrated effect to be identified that may not be selected by more traditional techniques. 相似文献
355.
Post-mortem metmyoglobin reduction in fresh venison 总被引:2,自引:0,他引:2
The accumulation of metmyoglobin (MetMb) at the surface of meat during storage contributes significantly to its discolouration. Under appropriate conditions it may be possible to utilise residual meat MetMb reducing activity to maintain fresh colour. Venison meat colour stability is poorer compared with other species. Hence, we evaluated the capacity of completely discoloured venison (n=12 animals) to reduce MetMb under anaerobic conditions in order to decipher more clearly the role MetMb reducing activity may play. The reducing capacity of venison (1 day, 3, and 6 weeks post-mortem), electrical stimulation, surface location (top and bottom) and rigor temperature (15 and 35°C) on MetMb were evaluated. Surface MetMb decreased (P<0.001) during storage while deoxymyoglobin increased (P<0.001) demonstrating MetMb reduction. Metmyoglobin reduction was greater (P<0.001) in venison which entered rigor at 15°C, the reduction at the bottom surface of the steaks was greater (P<0.001) compared with the top surface, and electrical stimulation had no affect (P>0.05). These data demonstrate that metmyoglobin reducing activity occurs anaerobically in completely discoloured venison following storage display. The practical application for this finding needs to be determined. 相似文献
356.
357.
X-linked inhibitor of apoptosis protein (XIAP), a member of the inhibitor of apoptosis protein family, is involved in regulating a number of functions including receptor-mediated intracellular signalling and early development. Its role as an endogenous caspase inhibitor, however, is the most highly characterised. Consequently, this protein has been implicated as an anti-apoptotic factor in the ovary. In vitro and in vivo studies have begun dissecting the stimuli and signalling networks that lead to XIAP upregulation in granulosa cells. The objective of this review is to briefly summarise the current knowledge concerning XIAP and its interactions with different caspases. Furthermore, XIAP's emerging role in the mammalian ovary will be explored and comparison is made with its functions in the mammary gland. Finally, the idea that XIAP may act as a molecular signalling switch in granulosa cells following detachment from underlying layers to promote follicular atresia will be introduced. 相似文献
358.
Mass spectrometry-based identification of the components of multiprotein complexes often involves solution-phase proteolytic digestion of the complex. The affinity purification of individual protein complexes often yields nanogram to low-microgram amounts of protein, which poses several challenges for enzymatic digestion and protein identification. We tested different solvent systems to optimize trypsin digestions of samples containing limited amounts of protein for subsequent analysis by LC-MS-MS. Data collected from digestion of 10-, 2-, 1-, and 0.2-microg portions of a protein standard mixture indicated that an organic-aqueous solvent system containing 80% acetonitrile consistently provided the most complete digestion, producing more peptide identifications than the other solvent systems tested. For example, a 1-h digestion in 80% acetonitrile yielded over 52% more peptides than the overnight digestion of 1 microg of a protein mixture in purely aqueous buffer. This trend was also observed for peptides from digested ribosomal proteins isolated from Rhodopseudomonas palustris. In addition to improved digestion efficiency, the shorter digestion times possible with the organic solvent also improved trypsin specificity, resulting in smaller numbers of semitryptic peptides than an overnight digestion protocol using an aqueous solvent. The technique was also demonstrated for an affinity-isolated protein complex, GroEL. To our knowledge, this report is the first using mass spectrometry data to show a linkage between digestion solvent and trypsin specificity. 相似文献
359.
Pan C Kora G Tabb DL Pelletier DA McDonald WH Hurst GB Hettich RL Samatova NF 《Analytical chemistry》2006,78(20):7110-7120
The abundance ratio between the light and heavy isotopologues of an isotopically labeled peptide can be estimated from their selected ion chromatograms. However, quantitative shotgun proteomics measurements yield selected ion chromatograms at highly variable signal-to-noise ratios for tens of thousands of peptides. This challenge calls for algorithms that not only robustly estimate the abundance ratios of different peptides but also rigorously score each abundance ratio for the expected estimation bias and variability. Scoring of the abundance ratios, much like scoring of sequence assignment for tandem mass spectra by peptide identification algorithms, enables filtering of unreliable peptide quantification and use of formal statistical inference in the subsequent protein abundance ratio estimation. In this study, a parallel paired covariance algorithm is used for robust peak detection in selected ion chromatograms. A peak profile is generated for each peptide, which is a scatterplot of ion intensities measured for the two isotopologues within their chromatographic peaks. Principal component analysis of the peak profile is proposed to estimate the peptide abundance ratio and to score the estimation with the signal-to-noise ratio of the peak profile (profile signal-to-noise ratio). We demonstrate that the profile signal-to-noise ratio is inversely correlated with the variability and bias of peptide abundance ratio estimation. 相似文献
360.
Alice Rocha Teixeira Netto Jos Hurst Karl-Ulrich Bartz-Schmidt Sven Schnichels 《International journal of molecular sciences》2022,23(9)
Dry eye is a multifactorial disease that affects the ocular surface and tear fluid. Current treatment options include lubricant eye drop application several times a day. However, these eye drops often cause local side effects like ocular allergies or blurred vision after the application. To test new treatment options, a robust dry eye model is needed. Here, a porcine ex vivo model was established by means of incubation of porcine corneas in low humidity (LH) and characterized by histological damage evaluation, epithelial thickness and by relevant dry eye markers, such as interleukin 1 beta (IL-1β), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), occludin and galectin-3. In the dry eye model proposed, an increased secretion of IL-1β was observed, as well as an upregulation of NF-κB, occludin and galectin-3 mRNA expression. Moreover, the model presented a higher rate of cell death in comparison to the controls. These effects could be reversed with successful treatment of dexamethasone (dexa) and partially reversed with hyaluronic acid (HA) containing eye drops. Furthermore, medium-molecular-weight HA stimulated an increase in IL-1β in the model proposed. In conclusion, this dry eye model mimics the in vivo condition and hence allows for animal-free testing of novel dry eye treatments. 相似文献