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41.
OBJECTIVE: To evaluate the significance of a diagnosis of atypical glandular cells, favor endometrial origin (AGC-EM), using cytohistologic correlation. STUDY DESIGN: A retrospective search identified 90 cervicovaginal smears (vaginal pool) with a diagnosis of AGC-EM, in 2 tertiary care medical centers between January 1998 and December 2002. RESULTS: Forty-six (51%) were conventional preparations and 44 (49%) were liquid-based monolayers (SurePath, TriPath Imaging Inc., Burlington, North Carolina, U.S.A.). Follow-up biopsies were available in 55 of 90 (61%) cases, 15 of 90 (17%) cases had cytology follow-up, and 20 of 90 (22%) were lost to follow-up. The patients ranged in age from 30 to 86 years (mean, 56); 56 of 90 (62%) were > 50 years. Among the patients who underwent biopsy, 22 (40%) had a clinically significant lesion, including 10 (18%) endometrial adenocarcinomas, 8 (15%) endometrial hyperplasias and 4 (7%) high grade squamous intraepithelial lesion/squamous cell carcinoma, nonkeratinizing type. The remaining 33 patients had benign histology, including benign endometrium, endometrial polyp, tubal metaplasia, cystic endometrial atrophy and cervical microglandular hyperplasia. Of the patients with cytologic follow-up, 2 had Pap smears showing atypical squamous cells of undetermined significance, while the remainder had negative results. CONCLUSION: In our study population, 40% (22 of 55) of women who underwent biopsy following a diagnosis of AGC-EM had significant uterine lesions, with the majority of the lesions endometrial in origin. Patients with a diagnosis of AGC-EM, especially those > 50, should be followed closely, and endometrial sampling should be included in their initial workup.  相似文献   
42.
OBJECTIVE: To evaluate the accuracy of fine needle aspiration biopsy (FNAB) in the diagnosis of vertebral lesions. STUDY DESIGN: Eighty-nine FNAB cases of vertebral lesions from January 1996 to December 2001 were retrieved from the Allegheny General Hospital laboratory information system. The cases were reviewed and correlated with clinical findings, including previous clinical history, primary site of malignancy and final pathologic diagnosis. RESULTS: ENAB diagnoses were malignant in 43 cases, benign in 35, suspicious in 1, unsatisfactory in 7 and false negative in 3. Previous clinical history included malignancy (37 patients), osteomyelitis and systemic disease (11), and nonspecific or no history (41). In 34 cases (38.2%) both aspirates and core biopsies were available, and the diagnoses correlated in 29/34 cases (85%). Surgical or core biopsies in the unsatisfactory/suspicious group showed malignancy in 4 cases (50%). The sensitivity of FNAB of vertebral lesions was 96%, specificity 100%, positive predictive value 100% and negative predictive value 92%, with no false positive cases. CONCLUSION: FNAB of vertebral lesions is an effective, sensitive and specific procedure in the diagnostic workup of a patient with or without a prior history of malignancy. Surgical pathology examination, including core biopsies of unsatisfactory or suspicious lesions, can further improve the diagnostic yield.  相似文献   
43.
A new chelating task-specific ionic liquid (TSIL), lutidinium-based salicylaldoxime ( LSOH ), and its square pyramidal vanadyl(II) complex (VO(LSO)2) have been successfully synthesized and structurally characterized using elemental (CHN), spectral, and thermal analyses. The catalytic activity of the lutidinium-salicylaldoxime complex (VO(LSO)2) in the alkene epoxidation reactions was studied under various reaction conditions, such as solvent effect, alkene/oxidant molar ratio, pH, reaction temperature, reaction time, and the catalyst dose. The results demonstrated that the CHCl3 solvent, 1 : 3 of the cyclohexene/H2O2 ratio, pH 8, temperature of 340 K, and catalyst dose of 0.012 mmol are assigned as the optimum conditions for achieving maximum catalytic activity for VO(LSO)2. Moreover, the VO(LSO)2 complex has the potential for application in the effective and selective epoxidation of alkenes. Notably, under optimal VO(LSO)2 conditions, cyclic alkenes convert more efficiently to their corresponding epoxides than linear alkenes.  相似文献   
44.
An efficient regulation of fuel metabolism in response to internal and environmental stimuli is a vital task that requires an intact carnitine system. The carnitine system, comprehensive of carnitine, its derivatives, and proteins involved in its transformation and transport, is indispensable for glucose and lipid metabolism in cells. Two major functions have been identified for the carnitine system: (1) to facilitate entry of long-chain fatty acids into mitochondria for their utilization in energy-generating processes; (2) to facilitate removal from mitochondria of short-chain and medium-chain fatty acids that accumulate as a result of normal and abnormal metabolism. In cancer patients, abnormalities of tumor tissue as well as nontumor tissue metabolism have been observed. Such abnormalities are supposed to contribute to deterioration of clinical status of patients, or might induce cancerogenesis by themselves. The carnitine system appears abnormally expressed both in tumor tissue, in such a way as to greatly reduce fatty acid beta-oxidation, and in nontumor tissue. In this view, the study of the carnitine system represents a tool to understand the molecular basis underlying the metabolism in normal and cancer cells. Some important anticancer drugs contribute to dysfunction of the carnitine system in nontumor tissues, which is reversed by carnitine treatment, without affecting anticancer therapeutic efficacy. In conclusion, a more complex approach to mechanisms that underlie tumor growth, which takes into account the altered metabolic pathways in cancer disease, could represent a challenge for the future of cancer research.  相似文献   
45.
46.
The main goal of this work was to make the cDNA-encoding subunit G2 of soybean glycinin, capable of self-assembly in vitro and rich in methionine residues. Two mutants (pSP65/G4SacG2 and pSP65/G4SacG2HG4) were therefore constructed. The constructed mutants were successfully assembled in vitro into oligomers similar to those occurred in the seed. The successful self-assembly was due to the introduction of Sac fragment of Gy4 (the codons of the first 21 amino acid residues), which reported to be the key element in self-assembly into trimers. The mutant pSP65/G4SacG2HG4 included the acidic chain of Gy4 (HG4), which was previously molecularly modified to have three methionine residues. This mutant will be useful in the efforts to improve the seed quality.  相似文献   
47.
Fibrillar forms of the Amyloid‐β (Aβ) protein have been implicated in the early stages of Alzheimer's disease (AD), however there are no standardised assays for soluble Aβ oligomer biomarkers that provide the best indication of the disease progression [1,2]. As a step towards a fast and label‐free method for testing different AD biomarkers, we have combined laser nano‐textured substrates with a SERS mapping technique and validated it using soluble Aβ‐40 oligomers [3‐5]. The nano‐textured SERS substrates provide fast (&5 min), label‐free spectra associated with soluble Aβ‐40 oligomers down to a concentration of 10 nM. Statistical analysis of the spectral intensities mapped over the substrate surface shows a quantitative correlation with the oligomer concentration.

Schematics of experiments: SERS mapping of Aβ‐40 (left figure: measured SERS intensity overlayed with an SEM image of ripples) was carried out on the laser nano‐textured (ripple) surface of sapphire and statistical analysis of the SERS intensity was carried out for qualitative (a high SERS intensity at low probability) and quantitative (a moderate SERS intenisty at the highest probability) measures. Quantitative statistical analysis of SERS mapping data can be performed off line for cross correlations with other known SERS signatures.  相似文献   

48.
Aiming at the reutilizing wastewater for algal growth and biomass production, a saline water rejected from reverse osmosis (RO) facility (salinity 67.59 g L−1) was used to cultivate the pre-adapted green microalga Chlorella vulgaris. The inoculum was prepared by growing cells in modified BG-11 medium, and adaptation was performed by applying a gradual increase in salinity (56.0 g L−1 NaCl and 125 ppm FeSO4·7H2O) to the culture in 200 L photobioreactor. Experiments using the adapted alga were performed using original-rejected water (ORW) and treated rejected water (TRW) comparing with the recommended growth medium (BG-11). The initial salinity of ORW was chemically reduced to 39.1 g L−1 to obtain TRW. Vertical photobioreactors (15 L) was used for indoor growth experiments. Growth in BG-11 resulted in 1.23 g L−1, while the next adaptation growth reached 2.14 g L−1 of dry biomass. The dry weights of re-cultivated Chlorella after adaptation were 1.49 and 2.19 g L−1 from ORW and TRW; respectively. The cellular oil content was only 12% when cells grown under control conditions verses to 14.3 and 15.42% with original and treated water, respectively. Induction of stress affected the fatty acid methyl esters (FAMEs) profile and the properties of the resulting biodiesel. The present results indicated that induction of stress by high salinity improves the quality of FAMEs that can be used as a promising biodiesel fuel.  相似文献   
49.
The following is a two-part study. Part A evaluates biomechanically intramedullary (IM) nails vs. locking plates for fixation of femoral fractures in osteoporotic bone. Part B of this study introduces a deterministic finite element model of each construct type and investigates the probability of periprosthetic fracture of the locking plate compared with the retrograde IM nail using Monte Carlo simulation. For Part A, an extra-articular, metaphyseal wedge fracture pattern was created in 11 osteoporotic fourth-generation composite femurs. Fixation was performed with a locking plate or a retrograde IM nail. Axial, torsion and bending cyclic loading to simulate post-operative damage accumulation were performed followed by ramped load to failure. Locking plates proved to be more stable (using stiffness as the determining factor) in osteoporotic bone as observed under low load cycle conditions. However, some of these advantages were offset by a greater incidence of sudden periprosthetic fracture observed under ramped loading conditions. Cadaveric, osteoporotic femurs included as a case study also exhibited periprosthetic fracture, but failure was accompanied by catastrophic comminution of the cortex. Periprosthetic failure at the implant end including bone comminution is difficult to salvage with revision fixation. The weakened trabecular matrix and thinned cortex of osteoporotic bone may increase the incidence of periprosthetic fracture. It is, therefore, essential for the surgeon to consider all possible loading scenarios when recommending an ideal implant for the osteoporotic patient.  相似文献   
50.
Constraint-based structure learning algorithms generally perform well on sparse graphs. Although sparsity is not uncommon, there are some domains where the underlying graph can have some dense regions; one of these domains is gene regulatory networks, which is the main motivation to undertake the study described in this paper. We propose a new constraint-based algorithm that can both increase the quality of output and decrease the computational requirements for learning the structure of gene regulatory networks. The algorithm is based on and extends the PC algorithm. Two different types of information are derived from the prior knowledge; one is the probability of existence of edges, and the other is the nodes that seem to be dependent on a large number of nodes compared to other nodes in the graph. Also a new method based on Gene Ontology for gene regulatory network validation is proposed. We demonstrate the applicability and effectiveness of the proposed algorithms on both synthetic and real data sets.  相似文献   
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