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111.
F Gonzalez RL Walton B Shafer WE Matory GL Borah 《Canadian Metallurgical Quarterly》1993,91(7):1270-1276
The condition macromastia has not been defined and characterized precisely by the medical community. Whether the patient with hypertrophic breasts is a candidate for or can be helped by reduction mammaplasty is unclear to both the medical and the lay community. A prospective study of 39 women undergoing reduction mammaplasty surgery was initiated to answer these questions. Patients rated the severity of their somatic pain symptoms and discomfort before reduction mammaplasty and again after complete recovery. The severity of their symptoms and complaints was numerically graded and analyzed. These data were compared with similar data obtained from 40 "small-breasted" women of similar age. Headache, neck pain, back pain, shoulder pain, and bra strap groove pain were present in 60 to 92 percent of patients, and 97 percent of patients had at least three of these pain symptoms preoperatively. All the patients had reduction of their pain symptomatology postoperative, and 25 percent of the study patients had total elimination of pain symptoms by reduction mammaplasty. The postoperative incidence and severity of pain symptoms and discomfort complaints were statistically equivalent to or less than the levels in the control group. 相似文献
112.
PURPOSE: A technique that eliminates the use of a mechanical "breast-bridge" for positioning tangential fields for treatment of the intact breast or chest wall has been developed. METHODS AND MATERIALS: Treatment set-up parameters are determined using measuring capabilities (gantry angles and source-skin distances) available on a standard simulator unit. A programmable scientific calculator is used to determine field geometry from polar coordinates for various points on the patient's skin. The calculator program determines the field size, a depth and lateral shift from a skin reference point to the isocenter for the tangential fields, and the gantry angles. The program provides additional information which facilitates the simulation process: First, the coordinates of the isocenter for the tangential fields are expressed relative to couch coordinates for an initial arbitrary isocenter so that the "auto go to" capability available on some simulators can be used. Second, the coordinates of the medial and lateral entry points can be edited when the first set of tangents are not accepted. This part of the program allows quick and efficient adjustment of the fields to obtain adequate treatment volume coverage and a minimum of irradiated lung or heart. RESULTS: Simulation of more than 300 patients has shown the technique to be a practical and efficient method for positioning tangential fields for breast or chest wall irradiation. CONCLUSION: The technique described here takes full advantage of the capabilities of the new generation of computer controlled simulators, and offers an alternative to previous methods employing a mechanical "breast-bridge." 相似文献
113.
Possibilities of involution of changes in lesser circulation after closure of experimental aortopulmonary anastomosis were studied. 37 observations at various intervals after closure of anastomosis (several minutes to 13.5 months) in 25 dogs were analyzed. Before closure the anastomosis had functioned for 1-7 months. The results of histological examinations of lungs, pressure measurements in lesser circulation, heart weight, electrocardiographic and spirographic examinations were analyzed. It was found that complete involution of changes in lesser circulation was possible only in first month of existence of anastomosis, in this case with changes of both "early" and "late" types. "Late"-type changes after four months function of anastomosis had both reversible and irreversible character, whereas "early"-type changes became irreversible already after three-month duration of anastomosis. With the "late"-type changes, the operation itself (closure of anastomosis) was accompanied by symptoms of pulmonary vasomotor paresis and heart failure, whereas in the presence of "early"-type changes the operation elicited no morphological or functional changes. 相似文献
114.
While polysemy has been discussed in communication studies for decades, a fundamental question has evaded systematic analysis: Which textual features make mediated texts open to multiple interpretations? Focusing on humor, we addressed this question by using a somewhat unusual point of departure–a failed intercoder reliability test. We analyzed 130 humorous forwards, of which 55 elicited disagreement between coders regarding the target of mockery and 75 were uncontroversial. Our comparative analysis yielded six textual attributes that augment polysemy in mediated humor: narrative‐valence discrepancies, unstereotypical stereotyping, debatable personality traits, self‐deprecating humor, intertextuality, and centrifugal multimodality. We demonstrate the utility of the proposed typology by analyzing public controversies stirred by humorous communication, and discuss its applicability to the study of audiences and nonhumorous genres. 相似文献
115.
Dougan DA; Malby RL; Gruen LC; Kortt AA; Hudson PJ 《Protein engineering, design & selection : PEDS》1998,11(1):65-74
The interactions between the Fab and single-chain Fv (scFv) fragments of an
antibody (NC10) and its antigen, influenza virus neuraminidase, were
analysed in the crystal structures of the Fab-neuraminidase and
scFv-neuraminidase complexes. To investigate the contribution to binding
made by cavities, salt links and hydrogen bonds in the antibody- antigen
interface, 14 single amino acid replacements were made at six contact
residues in the scFv fragment by site-directed mutagenesis. The binding
affinity of each mutant scFv antibody for neuraminidase was determined with
a BIAcore optical biosensor. Four of the mutations resulted in large
changes in the free energy of binding to neuraminidase (deltadeltaG > 1
kcal/mol) and together may account for approximately 70% of the free energy
of binding. Hence these data support the theory that a small number of
residues form the 'functional epitope' and are most important for binding
of NC10 to neuraminidase. The salt link between antibody residue (Asp)H56
and (Lys)N432 from neuraminidase was demonstrated to be important for
affinity, since substitution of (Asp)H56 with Asn caused a large reduction
in the free energy of binding (deltadeltaG = +2.8 kcal/mol). Hydrogen bonds
provided by (Tyr)L32 and (Asp)H56 were also important for binding: mutation
of (Tyr)L32 to Phe resulted in a significant reduction in binding affinity
(deltadeltaG = +1.7 kcal/mol). Disruption of hydrophobic interactions (van
der Waals contacts) led to significant reductions in affinity also
((Tyr)H99 to Ala, deltadeltaG = +1.5 kcal/mol; (Leu)L94 to Ala, deltadeltaG
> +3.0 kcal/mol). An attempt to increase binding affinity by filling a
cavity in the interface with a larger antibody side chain was unsuccessful,
as the free energy gained by new antibody-antigen interactions did not
compensate for the removal of cavity-bound water molecules.
相似文献
116.
117.
RR Bosch AM Patel SE Van Emst-de Vries RL Smeets JJ De Pont PH Willems 《Canadian Metallurgical Quarterly》1998,346(2-3):345-351
We investigated the effects of nitric oxide (NO) donors, S-nitroso-N-acetylpenicillamine and sodium nitroprusside on basal and K+-evoked release of [3H]noradrenaline from superfused synaptosomes from the rat cerebral cortex. Both substances produced concentration-dependent increases in the release of the labeled transmitter under basal and depolarized conditions. The effects of the donors on basal release were Ca2+-independent but were not inhibited by the carrier-uptake blocker, desipramine; the effects were abolished by hemoglobin (an NO scavenger). Thirty-five minutes after stimulation with sodium nitroprusside, the synaptosomes were still responsive to KCl stimulation, indicating that the donor's effects were not caused by damage to the synaptosome membrane. The cGMP analogue, 8-bromo-cGMP, had no effect on basal release, and the enhanced release produced by sodium nitroprusside was not inhibited by the specific inhibitor of soluble guanylate cyclase, 1H-[1,2,4]oxadiazolo[4,3-alpha]quinoxalin-1-one, indicating that NO's effects on basal release of the neurotransmitter are guanylate cyclase-independent. Both of the NO donors had more marked effects on release of [3H]noradrenaline during K+-stimulated depolarization. The NO-mediated increase in this case was partially antagonized by 10 microM LH-[1,2,4]oxadiazolo[4,3-alpha]quinoxalin-1-one, and 8-Br-cGMP was also capable of producing concentration-dependent increases in the K+-stimulated release of the transmitter. These findings indicate that the effects of the NO donors on [3H]noradrenaline release during depolarization are partially mediated by the activation of guanylate cyclase. 相似文献
118.
The classical action of the hormone 1,25-dihydroxyvitamin D3 (VD) is the regulation of calcium metabolism. In contrast, the peptide hormone atrial natriuretic factor (ANF) is one of the few known nonclassical VD responding genes. We screened the promoter of the rat ANF gene and identified a typical VD receptor (VDR) binding site formed by a direct repeat of two hexameric core binding motifs spaced by three nucleotides, between positions -907 and -891. Like most of the DR3-type VD response elements this sequence is bound with high affinity (Kd = 0.53 nM) by a heterodimer formed by VDR and retinoid X receptor. In a heterologous promoter context one copy of this sequence mediated an about fourfold gene activation by VD and a half-maximal activation (EC50) value of 0.48 nM VD. This characterizes the identified sequence as one of the most potent VD response elements. 相似文献
119.
120.