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The study presented comprises the initial and angiographic long-term results of a consecutive series of recanaliza-tion procedures in a single center. Between 1988 and 1992, a total of 400 patients underwent transluminal recanalization for total coronary occlusions. In 82% of successfully attempted patients, the occlusion could be passed by a standard guidewire. The overall initial success rate was 75% (298 of 400). The highest success rates could be achieved in the left circumflex artery (84%) and left anterior descending coronary artery (77%). Complications were uncomplicated myocardial infarction in ten patients (2.5%) and death in two patients (0.5%). Angiographic follow-up 3–6 months after recanalization could be achieved in 263 (88%) of 298 patients. Significant restenosis (≥ 50% minimum lumen diameter) was found in 57 (22%) of 263, and reocclusion was present in 38 (14%) of 263 patients, resulting in a total recurrence rate of 36%. In conclusion, recanalization can be performed with an initial success rate of 75% using bare-wire technique under the prerequisite operator experience. If a nearly complete angiographic follow-up is performed, the overall recurrence rate is 36%, which seems to be very acceptable in comparison with PTC A results for incomplete obstructions published so far . (J Interven Cardiol 1996;9:73–79)  相似文献   
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Germ cells in human testicular samples have been estimated by histology and quantitated by flow cytometry. There is an excellent relationship between the two techniques. These samples were classified histologically as "normal", "reduced number of germ cells" or "no germ cells". A definition of "normalcy" as determined by flow cytometry as having at least 38% of the cells in the haploid state, is proposed. Testicular samples from prepubertal boys with infiltrating leukemic cells often show an increase in the percentage of S-phase cells indicating the presence of tumor. These results indicate the value of flow cytometry in the identification of reproductive and neoplastic disorders.  相似文献   
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Abstract In an earlier study we demonstrated that the transfer of cholesteryl ester (CET) estimated as the net mass of CE lost from HDL to the apoB-containing lipoproteins (VLDL + LDL) during incubation of plasma is accelerated in normolipidaemic patients with insulin-dependent diabetes mellitus (IDDM). Recombination experiments with isolated lipoprotein fractions employing this same mass transfer assay indicated that this disturbance resulted from dysfunction of VLDL and not from changes in the activity of CE transfer protein (CETP). In this study, we sought first to determine whether CET estimated with an isotopic method that measures the transfer of radiolabelled CE from exogenous HDL from non-diabetic controls to endogenous VLDL + LDL was also increased in IDDM and, if so, the extent to which this disturbance was affected by glycaemic control, VLDL and CETP. As observed with the mass transfer assay, the rate of transfer of the HDL-CE label to VLDL + LDL was also significantly accelerated in IDDM plasma (IDDM: k = 0·256±0·07; control: k = 0·092±0·05; mean±SD; P < 0·001). Fasting glucose and fructosamine correlated with both isotopic transfer (k) (r= 0·54, P= 0·009; r= 0·57, P= 0·005, respectively) and the mass of CE transferred at 2 h (r= 0·55, P= 0·006; r= 0·59, P= 0·004, respectively). Recombination experiments revealed that isotopic CET was accelerated when: (a) IDDM VLDL were combined with controls HDL and d > 1·21 fractions; and (b) IDDM d > 1·21 plasma fractions containing CETP were combined with controls VLDL + LDL and HDL. While CETP concentrations in a subset of the study group were higher in the diabetic than in the non-diabetic controls, the difference was not statistically significant (IDDM 2·25±0·97 vs. control 1·58±0·58 μg ml-1; mean±SD; P<0·1). These findings indicate that dysfunction of VLDL and increased CETP concentrations both contribute to the pathological acceleration of isotopic transfer in IDDM plasma and that the magnitude of this proatherogenic defect correlates closely with glycaemic control.  相似文献   
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Between May 1985 and May 1991 we implanted 115 DFH-leads as unipolar atrial leads. The active fixation mechanism of this electrode consists of two sickle-shaped anchoring hooks which are placed at a distance of 0.9 mm parallel to the distal flat end of the electrode. All leads were affixed to the free wall of the right atrium. One hundred eight leads (93.9%) were implanted for dual chamber pacing and seven leads (6.1%) for single chamber atrial pacing. Parameters measured at implantation were (mean values): stimulation threshold 1.06 ± 0.42 V at 0.5 msec pulse width, P wave amplitude 5.12 ± 2.04 mV, and lead impedance 560 ± 76.1 Ohms. Within the first week after implantation, three early dislodgements occurred (2.6%). The follow-up period averaged 30.4 ± 16.2 months (range 2–76 months). During this time, 14 late macrodislodgements (12.2%) occurred after a mean period of 18.4 months (range 2–59 months). All of them required reoperation. The active fixation mechanism of the DEH-lead appears to be unreliable, if implanted in the free wall of the right atrium for dual chamber pacing.  相似文献   
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