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991.
We have constructed a recombinant adenovirus that carries the herpes simplex virus type I gene for thymidine kinase (EC 2.7.1.21) and expresses thymidine kinase under control of adenovirus major late promoter. A DNA fragment carrying thymidine kinase coding sequences but lacking the thymidine kinase promoter was sandwiched between a piece of adenoviral DNA and simian virus 40 early DNA on a plasmid. The aligned fragment was then inserted into the adenoviral genome, replacing internal adenoviral DNA. Hybrid viruses carrying the thymidine kinase gene were obtained by selecting for viruses that express simian virus 40 tumor antigen (T antigen) in monkey cells. The thymidine kinase gene was positioned in the third segment of the adenovirus tripartite leader downstream from the major late promoter by in vivo DNA recombination between the duplicated adenoviral sequences present in the plasmid insert and the viral vector. Levels of thymidine kinase activity in human or monkey cells infected with this hybrid virus were several times higher than in cells infected with herpes simplex virus. Infected cells produced thymidine kinase protein at very high levels, similar to those found for adenovirus late major capsid proteins. The thymidine kinase protein represented 10% of the newly synthesized protein in late infected cells and accumulated to represent 1% of total cell protein under optimal conditions. This vector system offers a procedure by which a variety of gene products that are biologically active and properly modified can be produced at high levels in mammalian cells.  相似文献   
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Lewis WR 《Cardiology Clinics》2005,23(4):531-9, vii
Using percutaneous angioplasty to induce the ischemic cascade in the cardiac catheterization laboratory, echocardiographic wall motion abnormalities have been documented to precede electrocardiographic abnormalities and angina. Therefore, detection of cardiac wall motion abnormalities is potentially more sensitive than the history, physical examination, and ECG for identification of myocardial ischemia. Echocardiography is highly reliable for assessing cardiac wall motion and, thus, it has been used for diagnosis and risk assessment in patients presenting to the emergency department (ED) with symptoms suggestive of myocardial ischemia. In patients who have acute ST-elevation myocardial infarction (MI), echocardiography is comparable to invasive left ventriculography for detecting wall motion abnormalities. However, the usefulness of echocardiography in the low-risk population that has chest pain of uncertain origin and a nondiagnostic initial presentation is less well established.  相似文献   
995.
An electronic theory of excitation is proposed and described in terms of a three-dimensional excited/ground-state energy surface which elucidates the photochemical and excited-state dynamics of rhodopsins. In this theory the primary action of light is to produce significant electron redistribution in the retinal, thereby generating new interactions that vibrationally excite and perturb the ground-state protein conformation. Thus, light energy causes charge redistribution in the retinal and induces transient charge-density assisted bond rearrangements (such as proton translocation) in the protein structure which is stabilized by subsequent retinal structural alteration. In this theory the isoprenoid chain of the retinal is considered a structurally pliable molecular entity that can generate charge redistributions and can be subsequently achieve intermediate conformations or various isomeric states to minimize the energy of the new protein structure generated by light. Thus, the 11-cis to all trans isomerization of the retinylidene chromophore is not considered a primary mechanism of excitation. An alternate biological role for this molecular process (which is eventually completed in all photoreceptors but not in bacterial rhodopsins) is to provide the irreversibility needed for effective quantum detection on the time scale of a neural response. Finally, it will be demonstrated that this mechanism, which readily accounts for the photophysical and photochemical data, can also be restated in terms of the Monod, Wyman, and Changeux terminology suggesting that aggregates of these pigments may function allosterically.  相似文献   
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997.
Anonymous nuclear markers were developed for Seychelles caecilian amphibians. Using a previously published bioinformatics pipeline (developed for Roche 454 data), 36 candidate anonymous nuclear loci (ANL) of at least 180 bp length were identified from Illumina MiSeq next generation sequencing data for five Seychelles species. We designed primer pairs for the 36 candidate ANL and tested these by PCR and Sanger sequencing. Seven ANL amplified and sequenced well for at least five of the six nominal Seychelles caecilian species (in three genera), and represent potentially useful markers for systematics and conservation.  相似文献   
998.
Though cortical abnormalities have been demonstrated in moderate and severe traumatic brain injured (TBI) patients, there have been no studies examining cortical changes following blast related mild TBI (mTBI). The purpose of this study was to determine the effects and functional relevance of blast mTBI on cortical thickness in a small cohort of carefully screened blast injured US Service Members (SM). Twelve SM with mTBI acquired through blast injury were compared to 11 demographically matched control SM without TBI. Both mTBI and control participants were active duty and had completed a combat deployment. Subjects underwent MRI examination and the T1 weighted anatomic images were processed using the FreeSurfer suite of tools. Cortical thickness maps were compared between groups and examined for relationships with time since injury (TSI). Utilizing a large database of functional imaging results (BrainMap), significant regions of interest (ROI) were used to determine the behavioral profiles most consistently associated with the specific ROI. In addition, clinical variables were examined as part of post-hoc analysis of functional relevance. Group comparisons controlling for age demonstrated several significant clusters of cortical thinning for the blast injured SM. After multiple comparisons correction (False Discovery Rate (FDR)), two left hemisphere clusters remained significant (left superior temporal (STG) and frontal (SFG) gyri). No clusters were significantly correlated with TSI after FDR correction. Behavioral analysis for the STG and SFG clusters demonstrated three significant behavioral/cognitive sub-domains, each associated with audition and language. Blast injured SMs demonstrated distinct areas of cortical thinning in the STG and SFG. These areas have been previously shown to be associated with audition and language. Post-hoc analyses of clinical records demonstrated significant abnormal audiology reports for the blast injured SM suggesting that the thinning in these ROIs might be related to injury to the external auditory system rather than direct injury to the brain from the blast. It is clear that additional replication is needed in much larger cohorts. Importantly, the combination of imaging tools and methods in this study successfully demonstrated the potential to define unique ROIs and functional correlates that can be used to design future studies.  相似文献   
999.
1000.

Background

The perioperative period of major oncologic surgery is characterized by immunosuppression, angiogenesis, and an increased load of circulating malignant cells. It is a window period in which cancer cells may seed, invade, and proliferate. Thus, it has been hypothesized that the use of regional anesthesia with the goal of reducing surgical stress and opioid and volatile anesthetic consumption would avoid perioperative immune suppression and angiogenesis and ultimately cancer recurrence.

Questions/purposes

We performed a systematic review of the literature on the use of regional anesthesia and postoperative analgesia to improve cancer-related survival after oncologic surgery. Our primary topic of interest is survival after orthopaedic oncologic surgery, but because that literature is limited, we also have systematically reviewed the question of survival after breast, gastrointestinal, and genitourologic cancers.

Methods

We searched the PubMed and Embase databases with the search terms: “anesthesia and analgesia”, “local neoplasm recurrence”, “cancer recurrence”, “loco-regional neoplasm recurrence”, “disease-free survival”, and “cumulative survival rates”. Our initial search of the two databases provided 836 studies of which 693 were rejected. Of the remaining 143 studies, only 13 articles qualified for inclusion in this systematic review, based on defined inclusion criteria. All these studies had retrospective design. Due to the high heterogeneity among the identified studies and the complete absence of randomized controlled trials from the literature on this topic, the results of a meta-analysis would be heavily confounded; hence, we instead performed a systematic review of the literature.

Results

No eligible studies addressed the question of whether regional anesthesia and analgesia have an impact on survival after musculoskeletal cancer surgery. Only one relevant clinical study was identified on regional breast cancer survival; it suggested a benefit. The literature on gastrointestinal and genitourinary surgery was larger but mixed, although some preliminary studies do suggest a benefit of regional anesthesia on survival after oncologic surgery in those patient populations.

Conclusions

Although basic science studies suggest a potential benefit of regional anesthesia and stress response reduction in cancer formation, we found little clinical evidence to support the theory that regional anesthesia and analgesia improve overall patient survival after oncologic surgery.  相似文献   
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