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951.
To evaluate the separation efficiency of Ericsson's two- and three-layer albumin separation methods, semen samples from 21 healthy males were studied. Seven patients already had two or more sons, another seven had two or more daughters and the other seven had primary infertility due to female factors. The semen samples were divided into three aliquots: one remained unprocessed initially, the other two aliquots went through two- and three-layer albumin separation methods respectively. All samples were then stained with X-Y double staining probes. In each group, four or five samples were processed at room temperature, and two or three at body temperature (37 degrees C). The labelling efficiency of X-Y double staining probe was over 99%. The X:Y sperm ratios were even in the original samples. The ratios of the X and Y spermatozoa were altered slightly but significantly after the two-layer (P < or = 0.05) or the three-layer (P < or = 0.005) separation. The alterations occurred only at room temperature. The X spermatozoa increased and the Y spermatozoa decreased, both to a small degree of difference (1.4-3.5%). Double fluorescence in-situ hybridization analysis therefore showed that albumin separation methods do not enrich Y spermatozoa. 相似文献
952.
JH Dequesne A Gallinat JG Garza-Leal CJ Sutton HF van der Pas K Wamsteker JG Chandler 《Canadian Metallurgical Quarterly》1997,42(5):311-318
OBJECTIVE: To test the hypothesis that treating dysfunctional uterine bleeding by automated application of electrothermal energy to the uterine cavity, with precise regional control, might yield results equivalent to those reported for hysteroscopically directed laser and electrosurgical endometrial ablations. MATERIALS AND METHODS: Patients with life style compromising menorrhagia, referred to six gynecologic surgical centers for hysterectomy or endometrial ablation, were admitted to the study if they had normal cervical cytology, a benign endometrial biopsy, no defined cause for their bleeding, and consented to participate in the evaluation of a newly developed Vesta DUB Treatment System. The device consists of a silicone-inflatable electrode carrier to be inserted into the uterine cavity and a controller to monitor and distribute current from a matched electrosurgical generator. Treatment involved a 3-minute or shorter warm-up period and a 4-minute treatment phase. RESULTS: Three- to 24-month follow-up data were available for 187 patients, with a mean follow-up of 14.8 months. The amenorrhea rate was 38%. Bleeding was reduced in 95% of patients. Actuarially, 88 +/- 3% of patients should expect to be free of menorrhagia, dissatisfaction, or need for a second procedure out to 24 months. CONCLUSIONS: The unique regional feed-back control offered by this system causes thorough, evenly distributed, thermal destruction 4-5 mm into the myometrium that reduces bleeding with durability equivalent to published reports of hysteroscopic endometrial ablation. 相似文献
953.
954.
955.
G. E. Fuchs 《Metallurgical and Materials Transactions A》1997,28(12):2543-2553
The hot compression behavior and microstructure evolution of ingot metallurgy (I/M) and powder metallurgy (P/M) processed
samples of the near-γ Ti-aluminide alloy, Ti-48Al-2Nb-2Cr (at. pct), were determined. Three I/M conditions and two P/M conditions were examined
in this study. Hot compression tests were performed in the temperature range of 1100 °C to 1300 °C at strain rates ranging
from 1.67×10−1/s to 1.67×10−4/s. The P/M materials consolidated by either hot isostatic pressing (“hipping”) or extrusion exhibited the best hot workability
in most cases. The P/M materials possessed finer, more homogeneous microstructures than the I/M materials. It was also noted
that improved workability was observed in materials with equiaxed microstructures without any lamellar constituents. 相似文献
956.
Anorectal manometry has been developed from an object of clinic oriented scientific interest to an established tool within the spectrum of proctologic diagnostics. At present it represents the only objective diagnostic method with regards to continence disorders; it is routinely applied in the evaluation of constipation, of incontinence, of pre- and postoperative conditions in diseases of the anorectum as well as in the indication and therapeutic control investigations during biofeedback training of the anal sphincter. The new technique of determination of the anal sphincter pressure vector volume allows for the most sensitive functional separation of patients with different degrees of continence; this method delivers a 3-dimensional graphic imaging of the sphincter pressure profile, thus allowing for an objective visualisation of the present mechanic defect and an aid in planning a surgical correction. 相似文献
957.
HP Sinn H Schmid H Junkermann J Huober G Leppien M Kaufmann G Bastert HF Otto 《Canadian Metallurgical Quarterly》1994,54(10):552-558
Primary (neoadjuvant) chemotherapy of locally advanced breast carcinomas is performed to locally reduce the tumour mass and to improve the operability. Recently, the indication for primary chemotherapy has been extended for preoperative treatment in breast conserving surgery. In an ongoing clinical trial we examined the resection specimens of 51 mammary carcinomas after primary chemotherapy. These patients had received a neoadjuvant therapy with epirubicin/cyclophosphamide for size reduction of large (> 3 cm) but operable tumours (pretreatment median tumour size 4.5 cm by mammography). The tumour response was evaluated pathologically and compared with the clinical tumour regression that was observed in over two-thirds of all cases. We classified the regressive changes using a semiquantitative scoring system from 0 to 4 (0 = no effect, 1 = resorption and tumour sclerosis, 2 = minimal residual invasive tumour [< 0.5 cm], 3 = residual noninvasive tumour only, 4 = no tumour detectable). The aim of this study was to evaluate the improvement of operability objectively and to correlate the histology of the primary tumour with the response to treatment. With invasive lobular carcinomas, the tumour size after therapy was reduced less than average and irrespective of the amount of histological tumour cell reduction, largely due to the stromal content of these neoplasms. Invasive ductal carcinomas with extensive or predominant intraductal component also underwent only a slight decrease in tumour size; this was because of the lack of tumour response with the intraductal component. Well differentiated tubular carcinomas were particularly resistant to primary chemotherapy.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
958.
Protracted diarrhea with insulin dependent diabetes mellitus (DM) and hypothyroidism in a 9 month old Japanese girl who was firmly suspected to have autoimmune enteropathy (AIE) is reported. Her severe secretory diarrhea failed to respond to intensive antidiarrheic treatment and was gradually improved with steroid therapy. The circulating autoantibodies to enterocytes in her serum were detected by indirect immunofluorescence technique and the impaired suppressor T (Ts) cell function was proved by plaque forming assay using bead-separated CD4 or CD8 T cells together with CD19 B cells. The anti-enterocyte antibodies were exclusively of immunoglobulin M (IgM) class and were detected with the progress of the protracted diarrhea. Maximum antibody titer was obtained at the onset of DM and the disappearance of autoantibodies was associated with the resolution of the clinical symptoms and signs. The helper functions of adult CD4 T cells to induce Ig-secreting cells from adult and the patient were strikingly suppressed by adult CD8 T cells. However, the CD8 T cells from the patient lost the ability to inhibit the induction of these Ig-secreting cells when stimulated with adult CD4 T cells. Moreover, the patient's CD8 T cells stimulated rather than suppressed the induction of Ig-secreting cells from the patient when stimulated with the patient's CD4 T cells. These results suggest that the impaired Ts cell function in this patient might play some immunological role in the pathogenesis of AIE. 相似文献
959.
960.