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951.
952.
OBJECTIVE: Although control of intraocular pressure (IOP) after cataract extraction may be of critical importance, little is known regarding changes in facility of outflow in the early postoperative period. The effect of phacoemulsification and conjunctival peritomy size on the coefficient of aqueous outflow facility (C) and IOP was studied. DESIGN: Participants were assigned randomly to one of two treatment groups. PARTICIPANTS: Seventy-four patients with cataract and without evidence of glaucoma were studied. INTERVENTION: Patients were randomized to receive either single- or two-quadrant conjunctival peritomy and phacoemulsification. MAIN OUTCOME MEASURES: Tonometry and tonography were assessed before surgery and at 1 day, 1 week, 6 weeks, and 1 year after surgery by a masked observer. RESULTS: Fifty patients with a mean of 11.4 months' (range, 10-13 months) follow-up were analyzed. Patients with reduced preoperative facility of outflow (as defined by C < or = 0.28 microliter/min/mmHg) showed a significant improvement from a mean preoperative value of 0.24 +/- 0.04 microliter/min/mmHg to 0.41 +/- 0.22 microliter/min/mmHg at 1 year (P = 0.002, N = 19). Among all patients, there was no significant change between mean preoperative C and last follow-up (0.39 +/- 0.23 vs. 0.46 +/- 0.38 microliter/min/mmHg, not significant [ns], N = 50). Furthermore, there was no significant change between mean preoperative and final IOP (23.7 +/- 4.1 vs. 23.3 +/- 3.9 mmHg, ns, N = 50). There was a significant elevation of mean IOP on postoperative day 1 to 27 +/- 6.2 mmHg (P = 0.001, N = 50). Patients with IOP elevations greater than 8 mmHg on postoperative day 1 had significantly elevated IOP at 1 year compared to preoperative values (P = 0.02, N = 12). There were no significant differences detected regarding C or IOP between single- or two-quadrant peritomy groups. CONCLUSIONS: Outflow facility improves after phacoemulsification in patients with a reduced preoperative coefficient of aqueous outflow. Postoperative day 1 IOP is significantly elevated after phacoemulsification. Conjunctival peritomy size does not appear to play a role in aqueous outflow facility or IOP after surgery. 相似文献
953.
Classification within the genus Pistacia has been based on leaf morphology and geographical distribution. Molecular genetic tools (PCR amplification followed by restriction analysis of a 3.2-kb region of variable chloroplast DNA, and restriction fragment length polymorphism analysis of the Pistacia cpDNA with tobacco chloroplast DNA probes) provided a new set of variables to study the phylogenetic relationships of 10 Pistacia species. Both parsimony and cluster analyses were used to divide the genus into two major groups. P. vera was determined to be the least derived species. P. weinmannifolia, an Asian species, is most closely related to P. texana and P. mexicana, New World species. These three species share a common origin, suggesting that a common ancestor of P. texana and P. mexicana originated in Asia. P. integerrima and P. chinensis were shown to be distinct whereas the pairs of species were monophyletic within each of two tertiary groups, P. vera:P. khinjuk and P. mexicana:P. texana. An evolutionary trend from large to small nuts and leaves with few, large leaflets to many, small leaflets was supported. The genus Pistacia was shown to have a low chloroplast DNA mutation rate: 0.05-0.16 times that expected of annual plants. 相似文献
954.
Nemaline (rod) myopathy is a congenital muscle disease with a wide spectrum of phenotypes, ranging from forms with neonatal onset and fatal outcome to asymptomatic forms. An adult-onset variant is characterized by large numbers of rod-containing myofibers, numerous rods per affected myofiber, and the absence of specific structural abnormalities typical of other muscle diseases. Few cases fulfilling these criteria have been described in the literature. Rare cases have had an associated inflammatory component, and the majority of these have occurred in patients with an underlying immunologic disorder. We present an unusual case of an immunologically competent 65-year-old man with late-onset nemaline myopathy, who was previously diagnosed with an inflammatory myopathy based on a muscle biopsy that contained chronic inflammation. His symptoms consisted of a 2-year history of progressive proximal muscle weakness; his family history was unremarkable. A neurologic examination confirmed the presence of bilateral proximal muscle weakness, normal sensation, and decreased upper and lower extremity reflexes. Creatine kinase levels were normal, and electromyographic findings indicated a myopathic process. A modified trichrome stain of the right biceps muscle revealed granular, basophilic, centrally located rods in the atrophic myofibers. Ultrastructurally, these myofibers contained osmiophilic rectangular structures with a latticelike appearance typical of nemaline myopathy. This case illustrates that adult-onset nemaline myopathy, although rare, should be considered in the differential diagnosis of an inflammatory myopathy. 相似文献
955.
Creating a population-based linked health database: a new resource for health services research 总被引:1,自引:0,他引:1
R Chamberlayne B Green ML Barer C Hertzman WJ Lawrence SB Sheps 《Canadian Metallurgical Quarterly》1998,89(4):270-273
Cytologically, the distinction between bronchioalveolar carcinoma and reactive/reparative processes of respiratory epithelium can be difficult. Retrospectively, we have identified 11 consecutive cases of bronchioalveolar carcinoma from the cytology files of University Missouri-Kansas City/Truman Medical Center. On average, a combined 5.71 cytologic/histologic procedures were performed before reaching a definitive diagnosis for this group. An additional seven random cases of reactive/reparative respiratory cases of adult respiratory distress syndrome patients were used as a control. Cytomorphometric analysis was performed. The mean average nuclear diameter for the carcinoma group was 13.76 microns and for the reactive/reparative group was 13.29 microns. There was no statistical difference between the two groups (paired student t test, P > .05). It appears from our data that mean nuclear diameter is not a discriminator for the cytologic distinction between bronchioalveolar carcinoma and reactive/reparative respiratory epithelium and that the accepted cytologic parameters of for bronchioalveolar carcinoma are more valid. 相似文献
956.
AG Kurkchubasche DG Fendya TF Tracy ML Silen TR Weber 《Canadian Metallurgical Quarterly》1997,132(6):652-7; discussion 657-8
957.
U-100592 and U-100766 are closely related antibiotics of the oxazolidinone class. Their in vitro activities were determined against 100 isolates of Staphylococcus aureus and 100 isolates of coagulase-negative Staphylococcus species by broth and agar dilution test methods. The MICs of both compounds by either test method at which 50 and 90% of isolates are inhibited were 2 and 4 micrograms/ml, respectively, for S. aureus and 1 to 2 micrograms/ml for coagulase-negative staphylococci. Time-kill assay with selected strains indicated a primarily bacteriostatic effect against staphylococci. 相似文献
958.
M Hansen SH Sindrup PB Christensen NK Olsen O Kristensen ML Friis 《Canadian Metallurgical Quarterly》1994,90(3):145-149
We have previously reported that polymorphonuclear granulocyte (PMN) and monocyte oxidative metabolism is reduced in polycythemia vera (PV) patients compared to healthy control subjects, after stimulation with cell surface receptor-dependent stimuli such as n-formyl-methionyl-leucyl-phenylalanine, leukotriene B4 and platelet-activating factor (PAF). In contrast, the oxidative response to phorbol myristate acetate (PMA) is normal. We now show that, in PV patients exhibiting significantly reduced PMN chemiluminescence after PAF stimulation, PAF induced platelet aggregation was also reduced--40 +/- 3% compared to 50 +/- 2% in controls (p < 0.01). The defective aggregatory response to PAF in PV remained over a wide range of stimuli concentrations. Platelet aggregation induced by PMA and ADP, however, was similar in PV and controls. In contrast, platelet aggregation induced by PAF (or by ADP and PMA) was not significantly reduced in patients with chronic myeloid leukemia, essential thrombocythemia and multiple myeloma. Furthermore, the release of beta-thromboglobulin was slightly but not significantly higher after PAF stimulation in PV and this argues against an abnormal PAF receptor as the cause of the defective function. Thus, not only PV neutrophils, but also PV platelets show a discrete defect of the stimulus response coupling for PAF, indicating a disease-specific abnormality that appears to be of clonal origin. 相似文献
959.
JA Ledbetter JA Francisco CB Siegall LK Gilliland D Hollenbaugh A Aruffo AW Siadak N Mischel-Petty LS Grosmaire ML Gordon TJ Brown P Moran-Davis RS Mittler PA Kiener SG Nadler 《Canadian Metallurgical Quarterly》1997,17(5-6):427-435
A single-chain Fv (sFv) was expressed from the variable regions of the CD40-specific mAb G28-5. The molecule bound CD40 with a high affinity (2.2 nM) and was a monomer in solution. Surprisingly, G28-5 sFv was a potent CD40 agonist that rapidly crosslinked CD40 on the cell surface but did not crosslink CD40-Ig in solution. G28-5 sFv was a more potent agonist than G28-5 IgG and was able to stimulate CD40 responses by B cells and monocytes. G28-5 IgG partially blocked, whereas G28-5 sFv augmented CD40 responses during stimulation with natural ligand (gp39-CD8 fusion protein). These results indicate that the functional activity of ligands built from the binding site of G28-5 is highly dependent upon the size and physical properties of the molecule both in solution and on the cell surfaces. 相似文献
960.
Y Zhu ML Moreno E Porqueras E Bourke A Bruzzi M Aletrari P Kanari D Partasidou J Nienhuis W Ferigo JL Robert JH Miller JM Spieser E Roets J Hoogmartens 《Canadian Metallurgical Quarterly》1996,14(8-10):1151-1156
A liquid chromatographic method for the analysis of ampicillin was examined in a collaborative study involving seven laboratories. The method included an isocratic part, which is used in the assay. The isocratic part is similar to the assay method for ampicillin of the US Pharmacopeia XXIII Revision. When the isocratic part is combined with gradient elution, the method is suitable for purity control. Six samples of ampicillin (anhydrous, trihydrate and sodium salt) with varying purity were analysed. The main component and related substances were determined. An analysis of variance proved the absence of consistent laboratory bias. The laboratory-sample interaction was significant. Estimates of the repeatability and reproducibility of the method, expressed as standard deviations of the result of the determination of ampicillin, were calculated to be about 0.9 and 1.1 respectively. 相似文献