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In the experiment on dogs and in patients with duodenal ulcer disease, it was established that the regulation of acid production besides the vagal nerves was mediated by the intragastric gastrin transport with the blood flow. A method of preoperative diagnosis of the intensity of intragastric blood flow permitting to define more accurately the indications for the choice of a method for surgical treatment has been developed. Supplementation of the selective proximal vagotomy with circular mucosectomy at the boundary between the antrum and body of a stomach enhances the effectiveness of operation due to reduction of the antral gastrin influence on the acid-producing zones of the stomach.  相似文献   
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The ascending colon of a guinea pig injected with tritiated thymidine was cut serially, autoradiographed and stained with periodic-acid-Schiff-hematoxylin. Maps of transversely sectioned crypts were prepared with the use of a microscope eye-piece projector. The number and angular positions of pulselabelled (DNA-synthesizing) cells around the circumference of transverse sections of the crypt were recorded. A method of “statistics of the circumference” was applied in order to find the variances of angular distances between labelled cells and thereby to find the type of arrangement of DNA-synthesizinbg cells in the crypt. The spatial distribution of DNA-synthesizing cells, both around the crypt circumference and along the crypt, was found to be non-random. While the pattern of nonrandomness around the crypt circumference is such that the DNA-synthesizing cells tend to occupy positions in the crypt circumference at maximal distances from each other, DNA-synthesizing cells along the crypt tend to occupy positions at minimal distances from each other. DNA-synthesizing cells are arranged in the crypt in rows, each consisting of several cells and each parallel to the long axis of the crypt. Apparently the dividing cell of the crypt produces either two proliferating or two differentiating cells. No evidence of differential mitosis could be found.  相似文献   
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Cross-bridge kinetics underlying stretch-induced force transients was studied in fibres with different myosin light chain (MLC) isoforms from skeletal muscles of rabbit and rat. The force transients were induced by stepwise stretches (< 0.3% of fibre length) applied on maximally Ca2+-activated skinned fibres. Fast fibre types IIB, IID (or IIX) and IIA and the slow fibre type I containing the myosin heavy chain isoforms MHC-IIb, MHC-IId (or MHC-IIx), MHC-IIa and MHC-I, respectively, were investigated. The MLC isoform content varied within fibre types. Fast fibre types contained the fast regulatory MLC isoform MLC2f and different proportions of the fast alkali MLC isoforms MLC1f and MLC3f. Type I fibres contained the slow regulatory MLC isoform MLC2s and the slow alkali MLC isoform MLC1s. Slow MLC isoforms were also present in several type IIA fibres. The kinetics of force transients differed by a factor of about 30 between fibre types (order from fastest to slowest kinetics: IIB > IID > IIA ≫ I). The kinetics of the force transients was not dependent on the relative content of MLC1f and MLC3f. Type IIA fibres containing fast and slow MLC isoforms were about 1.2 times slower than type IIA fibres containing only fast MLC isoforms. We conclude that while the cross-bridge kinetics is mainly determined by the MHC isoforms present, it is affected by fast and slow MLC isoforms but not by the relative content of MLC1f and MLC3f. Thus, the physiological role of fast and slow MLC isoforms in type IIA fibres is a fine-tuning of the cross-bridge kinetics.  相似文献   
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BACKGROUNDToday, biological fixation of uncemented press-fit acetabular components plays an important role in total hip arthroplasty. Long-term stable fixation of these implants depends on the osseointegration of the acetabular cup bone tissue into the acetabular cup implant, and their ability to withstand functional loads.AIMTo compare the strength of bone-implant osseointegration of four types of porous metal implants in normal and osteoporotic bone in rabbits.METHODSThe study was performed in 50 female California rabbits divided into non-ovariectomized (non-OVX) and ovariectomized groups (OVX) at 6 mo of age. Rabbits were sacrificed 8 wk after the implantation of four biomaterials [TTM, CONCELOC, Zimmer Biomet''s Trabecular Metal (TANTALUM), and ATLANT] in a 5-mm diameter defect created in the left femur. A biomechanical evaluation of the femur was carried out by testing implant breakout force. The force was gradually increased until complete detachment of the implant from the bone occurred.RESULTSThe breakout force needed for implant detachment was significantly higher in the non-OVX group, compared with the OVX group for all implants (TANTALUM, 194.7 ± 6.1 N vs 181.3 ± 2.8 N; P = 0.005; CONCELOC, 190.8 ± 3.6 N vs 180.9 ± 6.6 N; P = 0.019; TTM, 186.3 ± 1.8 N vs 172.0 N ± 11.0 N; P = 0.043; and ATLANT, 104.9 ± 7.0 N vs 78.9 N ± 4.5 N; P = 0.001). In the OVX group, The breakout forces in TANTALUM, TTM, and CONCELOC did not differ significantly (P = 0.066). The breakout force for ATLANT in the OVX group was lower by a factor of 2.3 compared with TANTALUM and CONCELOC, and by 2.2 compared with TTM (P = 0.001). In the non-OVX group, the breakout force for ATLANT was significantly different from all other implants, with a reduction in fixation strength by a factor of 1.9 (P = 0.001).CONCLUSIONTANTALUM, TTM, and CONCELOC had equal bone-implant osseointegration in healthy and in osteoporotic bone. ATLANT had significantly decreased osseointegration (P = 0.001) in healthy and in osteoporotic bone.  相似文献   
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Productivity trend information is valuable in developing policy and for understanding changes in the ‘value for money’ of the care system. In this paper, we consider approaches to measuring productivity of adult social care (ASC), and particularly care home services. Productivity growth in the public sector is traditionally measured by comparing change in total output to change in total inputs, but has not accounted for changes in service quality and need. In this study, we propose a method to estimate ‘quality adjusted’ output based on indicators of the Adult Social Care Outcomes Toolkit (ASCOT), using data collected in the annual adult social care survey (ASCS). When combined with expenditure and activity data for 2010 to 2012, we found that this approach was feasible to implement with current data and that it altered the productivity results compared with non-adjusted productivity metrics. Overall, quality-adjusted productivity grew in most regions between 2010 and 2011 and remained unchanged for most regions from 2011 to 2012.  相似文献   
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