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31.
A method is described for the screening of the new analgesic bromfenac via thin-layer chromatographic analysis of its acid hydrolysis product and subsequent Bratton-Marshall detection. 相似文献
32.
The influence of epitope density on the estimation of the affinity of antibody for complex antigens. 总被引:1,自引:0,他引:1
The influence of the epitope density of the antigen on antibody affinity values determined by fluid- and solid-phase immunoassays was assessed. The affinity of the interaction of a panel of monoclonal anti-DNP antibodies of different affinities (as determined by equilibrium dialysis) for DNP-protein conjugates of various hapten substitution ratios was used as the test system. The results obtained showed that the epitope density of the antigen markedly influences the observed affinity values obtained by both experimental approaches. However, the monoclonal antibodies were ranked in affinity terms by both assays in a similar order to that given by equilibrium dialysis. It is concluded that provided due care is exercised in choosing an appropriate epitope density for the test antigen, these methods can be used to provide rapid estimations of average antibody affinities. 相似文献
33.
C. Lazzari D. De Ronchi F. Mori L. Attard G. Verucchi F. Chiodo R. L. Holland 《Human psychopharmacology》1995,10(3):239-242
34.
In vivo multiple-mouse imaging at 1.5 T. 总被引:3,自引:0,他引:3
S Xu T P F Gade C Matei K Zakian A A Alfieri X Hu E C Holland S Soghomonian J Tjuvajev D Ballon J A Koutcher 《Magnetic resonance in medicine》2003,49(3):551-557
A multiple-mouse solenoidal MR coil was developed for in vivo imaging of up to 13 mice simultaneously to screen for tumors on a 1.5 T clinical scanner. For the coil to be effective as a screening tool, it should permit acquisition of MRIs in which orthotopic tumors with diameters >2 mm are detectable in a reasonable period of time (<1 hr magnet time) and their sizes accurately measured. Using a spin echo sequence, we demonstrated that this coil provides sufficient sensitivity for moderately high resolution images (156-176 microm in plane-resolution, 1.5 mm slice thickness). This spatial resolution permitted detection of primary brain tumors in transgenic/knockout mice and orthotopic xenografts. Brain tumor size as measured by MRI was correlated with size measured by histopathology (P < 0.001). Metastatic tumors in the mouse lung were also successfully imaged in a screening setting. The multiple mouse coil is simple in construction and may be implemented without any significant modification to the hardware or software on a clinical scanner. 相似文献
35.
The present paper reports on the inaugural meeting of the Mental Health Special Interest Research Group (SIRG) of the International Association for the Scientific study of Intellectual disability which was held at Fitzwilliam College, Cambridge, UK, in March 1998. The meeting was organized in conjunction with the Ninth Annual SIRG on ageing and intellectual disability. Representatives from North America, several European and Scandinavian countries, Australia, and Israel attended. Two broad themes had been determined prior to the meeting: ‘Improving the detection of mental health problems’ and ‘Research strategies for identifying risk factors for mental health problems’. In the presentations and subsequent discussions, it was apparent that there were extrenely diverse perspectives both across and within the different countries represented. Not only were individuals' experiences very different, but most strikingly, the theoretical frameworks were very diverse. This was partly a function of there being understandable differences in perspectives across disciplines, but at its most marked, there were fundamental differences in the way both intellectual disability and mental health were conceptualized. 相似文献
36.
G R Holland 《Proceedings of the Finnish Dental Society. Suomen Hammasl??k?riseuran toimituksia》1989,85(4-5):375-378
The activity in stimulated intrapulpal sensory nerve fibres can be increased by simultaneous stimulation of the sympathetic system. The anatomical basis for this interaction is unknown. Unmyelinated nerve fibres in the dental pulp are characterized by incomplete isolation and ensheathment. Individual pockets of Schwann cells often contain several axons in close contact within a confined space. If a pocket contained both sensory and adrenergic axons it is possible that activity in one could affect the properties of the other. Four young adult ferrets were, under general anesthesia injected intraperitoneally with the false neurotransmitter 6-hydroxydopamine which accumulates as dark vesicles within adrenergic axons. The animals were, still under general anesthesia, perfused four hours later with a fixative mixture. The canine teeth were removed, decalcified and prepared for electron microscopy. Ultrathin sections of the dental pulp were examined in the electron microscope. Convincingly labelled axons were rare. Labelled sympathetic axons were found in common Schwann cell pockets with unlabelled, presumably sensory, axons. This confirms studies in which degeneration has been observed following either surgical removal of the superior cervical ganglion or chemical sympathectomy. While this "axonal mingling" probably occurs in other sites it may be more extensive in the dental pulp. 相似文献
37.
S A Holland L C Hutton F N McKenzie 《Journal l'Association canadienne des radiologistes》1989,40(2):94-97
The chest radiographic findings and pulmonary radionuclide studies of four patients who underwent heart-lung transplantation between May 1983 and June 1986 were reviewed retrospectively. The two long-term survivors both developed bronchiolitis obliterans (presenting at 32 months postoperatively in the first patient and 14.5 months postoperatively in the second). The etiology of this is likely to be multifactorial and includes pulmonary rejection which may develop without concomitant cardiac rejection. The radiologist must be alert to this complication in heart-lung transplantation. The chest radiographs in our two patients showed diminution of peripheral bronchovascular markings and overinflation. The importance of careful screening of the radiographs of potential donors to detect pneumonia is emphasized. In one patient, a unilateral pneumothorax spread contralaterally due to the absence of normal anatomic barriers. The "reimplantation response" was not a prominent feature and was seen in one patient only. This response has been observed in heart-lung transplant recipients during the second postoperative week. The radiologic appearance is that of interstitial edema not explained by any clinical or hemodynamic findings. 相似文献
38.
A differential efficiency of adenovirus-mediated in vivo gene transfer into skeletal muscle cells of different maturity 总被引:8,自引:0,他引:8
Acsadi Gyula; Jani Agnes; Massie Bernard; Simoneau Maude; Holland Paul; Blaschuk Katharine; Karpati George 《Human molecular genetics》1994,3(4):579-584
High titre (10111012 pfu/ml) suspensions of autonomouslyreplication-defective type 5 human adenovirus (AV) recombinantswith different reporter gene inserts (CMV-Luciferase (Lux),CMV-ß-galactosidase (Lac Z), RSV-Lux and RSV-Lac Z)were injected Into intact quadrlceps muscles of 15 dayold (Group 1) or 3545 day old (Group 2) normal mice,as well as regenerating adult mouse muscles (Group 3) and 35day old mdx muscles (Group 4). The expression of the reportergenes was quantitated 10 days and 2 months later. At 10 dayspostinjection all reporter gene expression was very high inthe neonatally injected (Group 1) muscles. In Group 2 musclesthe transduction was markedly less. In Group 3 muscles the geneexpression was significantly better than in the Group 2 muscles.In adult mdx muscles (Group 4) where spontaneous regenerationis usually present, the results were similar to those in Group3 animals. At 2 months post-injection in Group 1 animals, theRSV-Lux expression was even higher than at 10 days postinjection.The cell surface density of 相似文献
39.
Neonatal treatments can disrupt prepulse inhibition (PPI) of startle response later in life. Alpha2A-adrenergic receptors (alpha2A-ARs) regulate the release of brain neurotransmitters that may influence PPI. The authors examined the effects of short-term reduction in the neonatal brainstem alpha2A-ARs on subsequent development of this receptor system and acoustic startle reflex in rats. Administration of antisense oligodeoxynucleotide complementary to the alpha2A-ARs on Days 2-4 of life reduced receptor expression in the brainstem by Day 5. The treatment increased alpha2-AR numbers in the cortex, hippocampus, and amygdala at 40 days of age, and in cortex and hypothalamus at 90 days of age. Transient increases in hippocampal and amygdalar alpha2-ARs were accompanied by attenuation of acoustic startle response and impairment of PPI. 相似文献
40.
Harawa NT Douglas J McFarland W Thiede H Kellogg TA Vorhees K Donovan KM Bingham TA 《Journal of acquired immune deficiency syndromes (1999)》2004,37(1):1206-1215
OBJECTIVES: Using data from anonymous unlinked testing of routinely collected sera, trends in HIV are compared among sexually transmitted disease patients in 4 Western urban centers. METHODS: Between 1989 and 1999, remnant sera obtained for routine syphilis testing from 256,819 patient visits to Denver, Los Angeles, San Francisco, and Seattle clinics were tested for HIV antibodies in an unlinked survey. HIV antibody test results were linked to anonymous demographic and risk information abstracted from the medical record. RESULTS: Overall cumulative HIV seroprevalences among women and among men who had sex exclusively with women were < or = 2%, declined over time, and did not exceed 8% among those who injected drugs. In contrast, cumulative HIV seroprevalences among men who have sex with men ranged from 13% in Seattle to 30% in San Francisco and declined a mean of 2.1% (95% CI, 1.6, 2.6) to 2.8% (CI 2.6, 3.1) per year, after adjustment. CONCLUSIONS: HIV infection declined over time across counties. Relative levels of HIV differed little by demographic and behavioral risk group despite differences in the severity of each county's epidemic. Because of the unique contribution of unlinked serosurveillance studies in monitoring these trends, their reinstitution in high-risk settings should be considered. 相似文献