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991.
H Pawar EL Bingham K Hiriyanna M Segal JE Richards PA Sieving 《Canadian Metallurgical Quarterly》1996,46(6):329-335
We studied 17 pedigrees with 108 affected males with X-linked juvenile retinoschisis (RS; McKusick No. 31270) and have analyzed all of the known polymorphic markers in the RS region of Xp22.1-p22.2 between DXS987 and DXS41. By haplotype analyses we found 7 individuals who showed crossovers in this interval surrounding RS. We previously reported AFM291wf5 as the centromeric boundary, and this remains unchanged in the present study. A new recombination was identified on the telomeric side at (DXS1195, DXS418). Our data support the locus order Xpter--(DXS987, DXS207, DXS1053, DXS43)--(DXS1195, DXS418)--(RS, DXS257, DXS999)--(AFM291wf5, DXS443)--DXS1052--(DXS1226, DXS274, DXS41)--Xcen; loci grouped in parentheses could not be mutually ordered by our genetic data. Physical mapping has indicated a distance of at most 900-1,000 kb between (DXS1195, DXS418) and AFM291wf5. No recombination was observed between RS and DXS257 which lies in our new interval of interest, but one critical individual was not informative with this marker. Our data now define the smallest RS inclusion interval. This interval is contained on a single YAC from which we have identified expressed sequences as candidate genes for RS. 相似文献
992.
993.
994.
RB Singh H Mori J Chen S Mendis M Moshiri S Zhu SH Kim RG Sy AM Faruqui 《Canadian Metallurgical Quarterly》1996,3(6):489-494
PURPOSE: Two types of glass wool were used to remove leukocytes in semen for evaluation of reactive oxygen species production by spermatozoa in oligozoospermic patients with leukocytospermia. METHODS: Semen samples were prepared using fine-structure glass wool (SpermFertil) and coarse-structure glass wool. In each treatment group, native semen was evaluated for sperm concentration, percentage motility, viability, leukocyte concentration, and production of reactive oxygen species. RESULTS: Electron microscopically, SpermFertil showed a higher number of leukocytes attached to the fibers compared to coarse-structure glass wool. Leukocytes in native semen and after glass wool filtration as determined by peroxidase cytochemistry confirmed this observation. Reactive oxygen species decreased from 45.303 counts/10(7) viable cells in native semen to 15.806 counts/10(7) cells in coarse structure wool and 7.465 counts/10(7) cells in Spermfertil, respectively. CONCLUSIONS: Removal of leukocytes from semen of oligozoospermic patients by means of glass wool filtration is a useful method to distinguish production of reactive oxygen species by leukocytes versus sperm cells. 相似文献
995.
The optimization problem corresponding to the design of a presteered broadband processor with maximally flat second-order spatial response in the look direction is discussed. The constraints corresponding to necessary and sufficient conditions for second-order flatness are presented. The nonlinearly constrained optimization approach is unable to consistently locate the global minimum. An approach to solving this problem that essentially converts the nonconvex optimization problem into a parameterized set of convex problems is presented. In the case of 2-D scenarios, the global optimum is determined by finding the roots of a cubic function. The characteristics of the constraints, including the minimum number required and the dependence on the choice of coordinate systems, are examined 相似文献
996.
We performed combined vitrectomy, lens removal and posterior chamber intraocular lens implantation for proliferative diabetic retinopathy in 120 eyes of 101 patients. Follow-up periods ranged from 3 to 63 months, with a mean of 17 months. Three lens removal methods were used: extracapsular cataract extraction (14 eyes), phacoemulsification and aspiration (49 eyes), and pars plana phacoemulsification (57 eyes). Preoperative rubeosis iridis or neovascular glaucoma was found in 21 eyes. Gas or temporary silicone oil tamponade was employed in 32 eyes. Surgical results were good, and the postoperative vision was finger counts or below only in 13 eyes. Thus the combined surgery proved to have no serious problems. Our results indicate two important points. (1) It is best to chose either of the following two methods for the lens surgery: phacoemulsification with continuous circular capsulorhexis, self sealing sclerocorneal incision, and in-the-bag fixation of the posterior chamber lens, or pars plana phacoemulsification leaving the anterior capsule, rub off and aspirating the lens epithelial cells, continuous circular capsulorhexis, and posterior chamber lens implantation in front of the anterior capsule from a self-sealing sclerocorneal wound. (2) It is mandatory to do complete vitrectomy and cut out the vitreous gels incarcerated in the sclerotomy site. 相似文献
997.
S Müller-Hülsbeck J Link H Schwarzenberg KP Walluscheck D Regensburger M Heller 《Canadian Metallurgical Quarterly》1997,122(9):775-80; discussion 781
Percutaneous stent placement has been described for treatment of aneurysms as an alternative to surgical therapy. Literature reports of percutaneous minimal invasive therapy of peripheral aneurysms shall be reviewed and compared with our own results. Six male patients (51-69 years) with femoropopliteal occlusions related to aneurysms were treated percutaneously. In two cases Wallstents and in four cases polyester-covered nitinol stents were applicated. A clinical investigation including doppler-ultrasound was performed 24 hrs, 1, 3, 6, 12 and 24 months after the intervention. Stent placement succeeded in all cases. No adjunctive surgical treatment was necessary. Ankle-brachial-index (ABI) improved from 0.22 +/- 0.2 before to 0.74 +/- 0.2 24 hours after the intervention. One patient was lost for follow-up (Wallstent). A decrease of ABI and additional intraarterial angiography revealed stent-graft occlusion within one month (n = 2) and within three months (n = 1). One of these cases was successfully recanalized with local fibrinolysis therapy. In three patients patency of the stent persisted for 24 (+/- 2) months follow-up with three-vessel-supply of the calf. These results warrant further investigations for this minimal invasive method of percutaneous stent deployment as an alternative to surgical bypass treatment of femoropopliteal aneurysms. Time of hospitalization was reduced. At this time, surgical treatment of peripheral vascular aneurysms is gold standard. 相似文献
998.
999.
The effects of duration of disease on serum angiotensin converting enzyme (ACE) was measured in 60 patients with endemic nephropathy (30 men and 30 women) of age between 30 and 60 years. There were formed three groups: patients with endemic nephropathy and duration of disease less than 5 years (n = 23), patients with endemic nephropathy and duration of disease between 5-10 years (n = 17); and patients with endemic nephropathy and duration of disease 10 years and more (n = 20). The serum ACE activity was determined by the spectrophotometric method using Hip-Gly-Gly as a substrate. The activity of enzyme were expressed in units corresponding to 1 nmol of the hippuric acid that was released by the hydrolysis of Hip-Gly-Gly per minute and ml of serum. The results showed that serum ACE activity decreased in group of patients with endemic nephropathy and duration of disease 10 years and more (29.21 +/- 2.25; X +/- SEM) in comparison with group of patients with endemic nephropathy and the duration of disease less than 5 years (35.57 +/- 1.75), which was statistically significant (p < 0.03). 相似文献
1000.
In arc welding processes, because of the complexity and nonlinearity of heat transfer phenomena, it is often difficult to design an effective control system based upon an exact mathematical model. In this paper, a self-organizing fuzzy control method is proposed to obtain a uniform weld quality by regulation of the surface temperature at a desired level. The proposed control system is designed to comprise a combined structure of the fuzzy SOC with conventional PD control for improving the system's stability. The control experiments show that the proposed controller guarantees a uniform weld quality for various welding conditions. 相似文献