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BACKGROUND: Intensive risk factor reduction in patients with dyslipidemias and coronary atherosclerosis has been shown to result in alterations in coronary artery morphology and reduced clinical events. However, the impact of such interventions in populations with relatively normal levels of low-density lipoproteins (LDL) is unclear. METHODS: To test the hypothesis that intensive risk factor reduction results in angiographic regression in patients with only mildly elevated levels of LDL, 14 patients with angiographically proven coronary atherosclerosis were entered into the University of California Davis Coronary Artery Disease Regression Program and intensively treated with pharmacologic and nonpharmacologic interventions for 2 years. Quantitative angiography was performed prior to and after 2 years of therapy to determine changes in coronary artery diameter. RESULTS: As a result of this program, dietary fat intake was reduced by 58% and LDL fell from 120 +/- 7 mg/dL to 104 +/- 6 mg/dL (p = 0.05). The average diameter of the measured arterial locations (including all 53 stenoses and 292 nondiscrete regions) on study entry was 2.74 +/- 0.05 mm. After 24 months, there was a net increase in arterial diameter (regression) of +0.05 +/- 0.04 mm to 2.81 +/- 0.05 mm (p = 0.01). While there was no significant change in the average diameter of discrete stenoses, all 8 lesions > or = 50% initial diameter narrowing regressed, with a mean diameter change of + 0.2 mm. Conversely, only 1 of 8 mild lesions < or = 20% regressed, while 4 progressed. Intermediate lesions (20% to 50%, n = 37) had balanced progression and regression. CONCLUSIONS: When examined as a continuous variable, there was a significant linear correlation between initial lesion severity (% stenosis) and the extent of regression (mm). Therefore, risk factor reduction (dietary therapy, exercise, psycho-social counseling, and lipid lowering therapy) in patients with only mild dyslipidemia results in angiographic regression of more severe lesions (> 50% initial stenosis), but does not prevent progression of mild lesions (< 20%). These findings demonstrate that intensive risk factor reduction in patients with only mild elevation of lipids beneficially influences the morphology of the most severe lesions.  相似文献   
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After reviewing the records of 111 patients with Fuchs' heterochromic iridocyclitis, we studied the therapy and prognosis of secondary glaucoma in 30 of these 111 patients (27%) who had glaucoma or could be considered glaucoma suspects. Maximal medical therapy was unsuccessful in 22 of the 30 patients (73%). Surgical intervention (mostly trabeculectomies, half with 5-fluorouracil) successfully controlled intraocular pressure (< or = 21 mm Hg with or without medication) in 13 of the 18 operated-on patients (72%) after a mean follow-up of 26 months. All successfully operated-on patients retained a visual acuity of 20/80 or better. We had favorable results, possibly because of modern surgical techniques (use of 5-fluorouracil, sodium hyaluronate) or earlier surgical intervention, or both.  相似文献   
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A small instrument is described which is operated on the stage of a light microscope to trim resin-embedded specimens to precise levels for subsequent ultramicrotomy and to cut thin pilot sections for light microscopy. The operating procedure and examples of results are given.  相似文献   
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We describe a systematic series of experiments on thermalization of electrons in lithographic metallic thin films at millikelvin temperatures using Coulomb blockade thermometry (CBT). Joule dissipation due to biasing of the CBT sensor tends to drive the electron system into non-equilibrium. Under all experimental conditions tested, the electron-electron relaxation is fast enough to ensure thermal electron distribution, which is also in agreement with the theoretical arguments we present. On the other hand, poor electron-phonon relaxation plays a dominant role in lifting the electron temperature above that of the bath. From a comparison of the results with the theoretical current-voltage characteristics of the thermometers we precisely determine the electron-phonon coupling constant for the common metals used. Our experiments show that it is a formidable task to attain thermal equilibrium with the bath using single-electron devices under non-zero bias conditions at 20–50 mK temperatures that are typically encountered in experiments. The conclusion concerning Coulomb blockade thermometry is more optimistic and two-fold: (1) One can now correct the errors due to bias heating in a satisfactory manner based on known material properties and the size of the metal films in the sensor. (2) Reliable thermometry down to 20 mK requires islands whose volumes are >10?15 m3, which is still acceptable both from the parameter (capacitance) and fabrication points of view.  相似文献   
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The challenge of Duchenne muscular dystrophy (DMD) carrier identification resides in the ability to identify the presence of a mutant gene over the background contributed by the normal allele. Current diagnosis of carrier status when a deletion has been identified in a proband is based on an analysis of a gene dosage. We present a diagnostic strategy that uses fluorescence in situ hybridization (FISH) to detect female carriers with major deletions in the dystrophin gene. We screened a human X-chromosome-derived genomic library with a full-length dystrophin cDNA and isolated 15 dystrophin-specific cosmids that contain DMD gene exons. Six cosmids were further tested as FISH probes in control individuals and subsequently applied on chromosomes from eight males with DMD and known deletions and on samples from three female carriers. As expected, X chromosomes in normal females displayed four signals, two for the DMD-specific probe and two for the X-chromosome centromeric probe. Hybridization on chromosomal spreads from carriers of deletions revealed only one signal from the DMD-specific probe and two from the control centromeric probe. Males carrying deletions showed no DMD-specific signal for the deleted exons tested. Our data indicate that FISH could represent an alternative method for the detection of female carriers with DMD gene deletions.  相似文献   
8.
Spores of Bacillus subtilis NCTC 8236 were treated with glutaraldehyde, Lugol's iodine, polyvinylpyrrolidone-iodine (PVP-I), sodium hypochlorite or sodium dichloroisocyanurate (NaDCC). After exposure survivors were enumerated on nutrient agar containing potential revival agents (subtilisin, lysozyme, calcium dipicolinate, calcium lactate). Of these, only calcium lactate had any significant enhancing effect and then only with iodine-treated spores. Calcium lactate (9 mmol l-1) in nutrient broth enhanced the rate and extent of germination of iodine-treated spores but not of spores previously subjected to glutaraldehyde, hypochlorite or NaDCC.  相似文献   
9.
Prostaglandin E2 levels in isolated rat islets were increased from 64 +/- 11 pg/30 islets when incubated in medium containing 2 mM glucose to 115 +/- 9 pg/30 islets in medium containing 20 mM glucose. In contrast, glyceraldehyde (10 mM) reduced prostaglandin E2 levels to 29 +/- 6 pg/30 islets. Inhibition of glucose metabolism by mannoheptulose (10 mM) abolished the stimulatory effect of glucose on prostaglandin E2 levels and inhibited glucose-induced insulin release. The cyclooxygenase inhibitor, flurbiprofen (20 microM), did not affect insulin release caused by glucose or glyceraldehyde. In the presence of 1 mg/ml bovine serum albumin, insulin secretion induced by 20 mM glucose (6.9 +/- 1.1% of islet insulin content) was reduced by the lipoxygenase inhibitor BW755 C (20 microM) to 3.1 +/- 0.6%, and by the phospholipase A2 inhibitor, p-bromophenacyl bromide (10 microM), to 2.1 +/- 0.8%. In the absence of bovine serum albumin the inhibitory action of BW755 C and p-bromophenacyl bromide on glucose-induced insulin release was significantly more pronounced. These drugs whether in the presence or absence of bovine serum albumin, did not affect glyceraldehyde-stimulated insulin secretion. Glyceraldehyde (10 mM), potentiated glucose-induced insulin release in the presence of 2-8 mM glucose, but not for 10-20 mM glucose. Although the phospholipase A2 activator, melittin, initiated insulin release in the presence of 2 mM glucose and enhanced 10 mM glyceraldehyde-stimulated insulin secretion it had no effect on 20 mM glucose-induced insulin release. These two stimulatory effects of melittin on insulin release were totally abolished by p-bromophenacyl bromide.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
10.
This paper looks into a new area for knowledge-based system application, that of manufacturing modelling. Manual generation of IDEF0 models of manufacturing systems is time-consuming and inconsistent. However, the process can be automated to improve timeliness and consistency. In this paper, a knowledge-based manufacturing modelling system for the automatic generation of IDEF0 models is proposed. The system will not only greatly reduce the IDEF0 modelling time but will also eliminate the inconsistency problem of conventional IDEF0 modelling systems. The paper explains the knowledge-based approach and identifies the kinds of domain knowledge that are required for the construction of the knowledge-based manufacturing modelling system.  相似文献   
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