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11.
We report the close correlation between changes in serum immunoreactive vascular endothelial growth factor 165 (iVEGF165) levels and metastatic tumor burden measured by computed tomography scan before treatment, during the antitumor response, and during early progression in a patient treated with ex vivo gene therapy for renal cell carcinoma. With the researcher blinded to outcome, iVEGF levels were measured in archived serum samples from a patient with metastatic renal cell carcinoma who demonstrated a 7-month partial remission to treatment with autologous, irradiated human GM-CSF gene transduced tumor vaccine. Although a spontaneous regression could not be formally excluded in this patient, the appearance of 20 new pulmonary metastases on computed tomography scan after nephrectomy and before vaccination indicates that if spontaneous regression occurred, it took place at the start of vaccine treatment.  相似文献   
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Searches of the major public protein databases with core and linker chicken and human histone sequences have resulted in the compilation of an annotated set of histone protein sequences. In addition, new database searches with two distinct motif search algorithms have identified several members of the histone fold family, including human DRAP1 and yeast CSE4. Database resources include information on conflicts between similar sequence entries in different source databases, multiple sequence alignments, links to the Entrez integrated information retrieval system, structures for histone and histone fold proteins, and the ability to visualize structural data through Cn3D. The database currently contains >1000 protein sequences, which are searchable by protein type, accession number, organism name, or any other free text appearing in the definition line of the entry. All sequences and alignments in this database are available through the World Wide Web at http://www.nhgri.nih. gov/DIR/GTB/HISTONES or http://www.ncbi.nlm.nih. gov/Baxevani/HISTONES  相似文献   
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Absolute rate constants and degradation efficiencies for hydroxyl radical reactions with seven low-molecular-weight nitrosamines in water have been evaluated using a combination of electron-pulse radiolysis/absorption spectroscopy and steady-state radiolysis/GCMS measurements. The hydroxyl radical oxidation rate constants were found to depend upon nitrosamine size and to have a very good linear correlation with the number of methylene groups in these compounds. This correlation, given by In(k x OH) = (19.72 +/- 0.14) + (0.424 +/- 0.033) (#CH2), suggests that hydroxyl radical oxidation predominantly occurs by hydrogen atom abstraction from constituent methylene groups in each of these nitrosamines. In contrast, the hydrated electron reduction rate constants measured for these compounds were remarkably consistent, with an average value of (1.67 +/- 0.22) x 10(10) M(-1) s(-1). These reduction kinetic data are consistent with this predominantly diffusion-controlled reaction occurring at the N-NO moiety in these carcinogens. From steady-state radiolysis measurements under aerated conditions, specific hydroxyl radical degradation efficiencies for each nitrosamine were evaluated. For larger nitrosamines, the efficiency was constant at 100%; however, for the smaller alkyl substituted species, the efficiency was significantly lower, with a minimum value of only 80% determined for N-nitrosodimethylamine. The reduced efficiency is attributed to radical repair reactions competing with the slow peroxyl radical formation.  相似文献   
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OBJECTIVE: To describe the pattern of inpatient hospital utilization, up to 15 years after injury, among a cohort of veterans with service-connected traumatic spinal cord injury (SCI). PATIENTS: A cohort of 1,250 male veterans, with traumatic SCI occurring between 1970 and 1986, who visited the VA within 1 year of injury, was assembled from VA administrative files; diagnosis was verified by examining hospital discharge summaries. DESIGN: Computerized record linkage among Department of Veterans Affairs (VA) administrative files was used to determine patterns of inpatient hospital utilization. MAIN OUTCOME MEASURE: Pattern of inpatient admissions and length of stay (LOS). RESULTS: Patients were typically white males injured in their mid-twenties. The initial VA hospitalization began approximately 6 weeks after injury and lasted 4 to 7 months, depending on injury level and completeness. Subsequent hospitalizations usually lasted approximately 10 days, but 22% of stays exceeded 1 months. Most hospitalizations took place in specialized SCI Centers. Comparing the 1980s with the 1970s, patients in the 1980s entered VA facilities sooner after injury, were more likely to visit SCI Centers, and had shorter initial stays. Rates for the incidence of rehospitalization decreased rapidly in years 2-5 after injury and declined less rapidly thereafter. Occupancy rates and proportion rehospitalized followed similar patterns. The incidence rate for persons with complete quadriplegia was approximately twice that of patients with incomplete paraplegia. Between 1970 and 1991, both the rehospitalization incidence rate and LOS decreased by approximately 20%. Only 10% of patients accounted for 46% of the total LOS. LOS during the first five years was predictive of later LOS. CONCLUSIONS: The pattern of rehospitalization in VA facilities was generally consistent with that of the Model Systems. Efforts toward preventing rehospitalization should target persons with previous high utilization.  相似文献   
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AS Landsman  TJ Chang 《Canadian Metallurgical Quarterly》1998,37(2):122-7; discussion 172
The authors evaluated the value of plastic foam models for approximating the mechanical properties of cadaveric bone. Three mechanical tests (3-point bending, cantilevered load to failure, screw push-out) were performed to evaluate the performance of fresh (nonpreserved) human metatarsals, plastic solid foam anatomic models, and modified anatomic models. The test results indicate that plastic models may simulate the mechanical properties of natural bone in tests in which only elastic deformation is achieved. However, under circumstances where load is applied until material failure, the mechanical properties vary dramatically. These tests indicate that specific goals should be established with these results in mind, when planning mechanical testing studies with either plastic or cadaveric models.  相似文献   
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The AT-hook is a small DNA-binding protein motif which was first described in the high mobility group non-histone chromosomal protein HMG-I(Y). Since its discovery, this motif has been observed in other DNA-binding proteins from a wide range of organisms. Using pattern searches and position-dependent matrices, we have extracted the AT-hook motifs present in a non-redundant protein sequence database. We have classified these motifs into three types according to their sequence similarity and have found that they are prevalent in many eukaryotic nuclear proteins in single or multiple copies. Furthermore, AT-hook motifs are frequently associated with known functional domains seen in chromatin proteins and in DNA-binding proteins (e.g. histone folds, homeodomains and zinc fingers). In general, it appears that the AT-hook motif is an auxiliary protein motif cooperating with other DNA-binding activities and facilitating changes in the structure of the DNA either as a polypeptide on its own [e.g. HMG-I(Y)] or as part of a multidomain protein [e.g. Swi2p in Saccharomyces cerevisiae or HRX (ALL-1) in Homo sapiens]. It is most interesting that this motif seems to be quite specific to known or predicted chromosomal/DNA-binding proteins, suggesting that it may act as a versatile minor groove tether.  相似文献   
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BACKGROUND: The aim of this study was to assess the influence of race on the treatment and survival of patients with colorectal carcinoma. METHODS: This retrospective cohort study included all white or black male veterans given a new diagnosis of colorectal carcinoma in 1989 at Veterans Affairs Medical Centers nationwide. After adjusting for patient demographics, comorbidity, distant metastases, and tumor location, the authors determined the likelihood of surgical resection, chemotherapy, radiation therapy, and death in each case. RESULTS: Of the 3176 veterans identified, 569 (17.9%) were black. Bivariate analyses and logistic regression revealed no significant differences in the proportions of patients undergoing surgical resection (70% vs. 73%, odds ratio 0.92, 95% confidence interval 0.74-1.15), chemotherapy (23% vs. 23%, odds ratio 0.99, 95% confidence interval 0.78-1.24), or radiation therapy (17% vs. 16%, odds ratio 1.10, 95% confidence interval 0.85-1.43) for black versus white patients. Five-year relative survival rates were similar for black and white patients (42% vs. 39%, respectively; P=0.16), though the adjusted mortality risk ratio was modestly increased (risk ratio 1.13, 95% confidence interval 1.01-1.28). CONCLUSIONS: Overall, race was not associated with the use of surgery, chemotherapy, or radiation therapy in the treatment of colorectal carcinoma among veterans seeking health care at Veterans Affairs Medical Centers. Although mortality from all causes was higher among black veterans with colorectal carcinoma, this finding may be attributed to underlying racial differences associated with survival. This study suggests that when there is equal access to care, there are no differences with regard to race.  相似文献   
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Resource management agencies in the Laurentian Great Lakes routinely conduct studies of fish movement and migration to understand the temporal and spatial distribution of fishes within and between the lakes and their tributaries. This literature has never been summarized and evaluated to identify common themes and future research opportunities. We reviewed 112 studies, published between 1952 and 2010, with the goal of summarizing existing research on the movement and migration of fishes in the Laurentian Great Lakes. The most commonly studied species were Lake Trout (Salvelinus namaycush), Walleye (Sander vitreus), and Lake Sturgeon (Acipenser fulvescens). Studies relied mainly on mark-recapture techniques with comparatively few using newer technologies such as biotelemetry, hydroacoustics, or otolith microchemistry/isotope analysis. Most movement studies addressed questions related to reproductive biology, effects of environmental factors on movement, stocking, and habitat use. Movement-related knowledge gaps were identified through the literature synthesis and a survey distributed to Great Lakes fisheries managers. Future studies on emigration/immigration of fishes through lake corridors, the dispersal of stocked fishes and of stock mixing were identified as being particularly important given their potential for developing lake- or region-wide harvest regulations and stocking strategies. The diversity of tools for studying fish movement across multiple years and various spatial scales gives researchers new abilities to address key science questions and management needs. Addressing these needs has the potential to improve upon existing fisheries management practices within the complexity of multi-jurisdictional governance in the Laurentian Great Lakes.  相似文献   
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