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11.
1. The aim of the present study was to compare electrolyte handling in naturally reared neonatal spontaneously hypertensive rats (SHR) with those reared by a Wistar-Kyoto (WKY) rat foster mother (denoted SHRX), as cross-fostering SHR pups to a WKY rat dam lowers adult blood pressure in the SHR. 2. The electrolyte content of WKY rat and SHR dams’ milk was determined and electrolyte intake and urinary excretion rates were calculated in both naturally reared and cross-fostered WKY rat and SHR pups. 3. The milk sodium concentration fell in both strains (WKY rat: 31.8 ± 2.0 to 15.2 ± 1.2 mmol/L; SHR 31.9 ± 2.5 to 18.2 ± 1.6 mmol/L; P < 0.001), as did potassium (P < 0.001), over lactation, but there were no differences between strains. Calcium and magnesium concentrations increased (P< 0.001), although SHR dam's milk contained less calcium (P < 0.001) than that of WKY rat dams during the third week of lactation. 4. Spontaneously hypertensive rat pups ingested less milk (P<0.05) than WKY rat pups; therefore, their cumulative sodium intake over postnatal days 4–15 was significantly lower than that of WKY rat pups (WKY rat vs SHR: 84.4 ± 3.6 vs 59.7 ± 2.6 μmol/g bodyweight, respectively; P < 0.05) and fostered SHRX pups (77.7 ± 7.0 μmol/g bodyweight; P < 0.05). Potassium and magnesium intakes were comparable between SHR, WKY rat and SHRX pups, but SHR pups ingested significantly less calcium than either WKY rat pups (136.1 ± 6.4 vs 200.1 ± 9.5p, mol/g bodyweight, respectively; P<0.05) or SHRX pups (200.0 ± 18.0 μmol/g bodyweight; P<0.05). 5. These data show that the neonatal SHR experiences a period of sodium deficiency during the developmental stage when cross-fostering is effective in lowering blood pressure. This is consistent with the reported up-regulation of the renin-angiotensin system observed in SHR at this time and may have a long-term influence on blood pressure.  相似文献   
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Objects We designed several distraction devices and applied these instruments in 14 patients with varying types of craniosynostosis. The aim of this report is to clarify the advantages and disadvantages of these surgical methods and to discuss current concepts for the surgical strategy in the treatment of craniosynostosis. Methods From January 2000 to July 2005, 28 patients with craniosynostosis were retrospectively analyzed. Surgical treatment was performed on 14 patients using the distraction method with internal distraction devices that we designed, in which 5 patients had plagiocephaly, 3 brachycephaly, and 6 scaphocephaly. All patients underwent preoperative and postoperative evaluations, which included the patient’s neurological state, and three-dimensional CT. Results With distraction devices, the time required for the surgery could be shortened almost 3 1/3 h; the bleeding during the surgery was decreased with reduced requirement of more than 200 ml of blood transfusion as compared with remodeling surgery. Postoperatively achieved distraction distances varied from 30.0 to 47.5 mm (mean, 42.99 mm). The average increased volume percent of cranium in distraction surgery group was 20.9% (range, −11.5 to 58.9%) after full distraction. Conclusion With distraction surgery, satisfactory cranial volume expansion and aesthetically pleasing morphological states were achieved in all cases, and the efficacy was statistically significantly high as compared with remodeling method.  相似文献   
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We describe the pattern and progression of atrophy delineated using fluid registration of serial magnetic resonance imaging scans in a case of multiple system atrophy (MSA). The in vivo findings were consistent with those found at postmortem, including significant supratentorial atrophy concurrent with an unusual degree of cognitive impairment for MSA.  相似文献   
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Minimally invasive surgery offers quicker recovery and less morbidity for our patients through smaller surgical wounds and less tissue trauma. Although minimally invasive surgery has progressed in other fields of surgery for many years, spine surgeons have not previously embraced this philosophy for the various reasons discussed. However, minimally invasive spinal surgery has gained much interest in recent years. With the advent of new instrumentation, technology, and techniques, the promise of minimally invasive surgery in the spinal arena has become a reality. With the use of the microscope, navigational tools, newly developed canula for retraction, and image-guided percutenous pedicle screw systems, we can accomplish the same surgical procedures as currently used through smaller wounds and with greater precision. Nevertheless, all new technology does offer us an initial challenge of steep learning curves. Minimally invasive should not equate to minimal and inadequate treatment for our patients. Furthermore, careful analysis of this new technique is underway to assess its true advantages as compared with our current and proven techniques.  相似文献   
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Background: Many studies have addressed the effect of the timing of surgery for breast cancer relative to menstrual cycle phase, with conflicting results. Explanations for the possibility that survival could be altered by the appropriate timing of breast cancer surgery in humans remain speculative. Methods: We examined the expression of three estrogen related proteins (c-erbB-2, cathepsin D, pS2) in the breast tumors from 69 premenopausal women sampled in different phases of the menstrual cycle. Data on S-phase fraction and hormone receptor expression were also analyzed. Immunohistochemical assays were used to measure the proteins of interest. S-phase fraction was determined by flow cytometry. Analyses were performed based on fraction of cells staining positive for the protein, density of stain, and a histoscore that combined both fraction of positive cells and density. Results: We found no differences in c-erbB-2, cathepsin D, hormone receptor, or S-phase levels in tumors sampled in the follicular versus luteal phase, or perimenstrual versus periovulatory phase. The exception was pS2, which was expressed at greater levels during the luteal than during the follicular phase of the cycle (p<0.01); but there was no difference in pS2 expression when the patients were classified as periovulatory versus perimenstrual. Conclusions: Our findings do not support a variation in c-erbB-2, cathepsin D, S-phase fraction, or receptor expression as an explanation for the differences in breast cancer prognosis when surgery is timed by menstrual cycle phase. The finding that pS2 (an indicator of hormone sensitivity, and possibly better prognosis) is expressed at higher levels in tumor samples during the luteal phase suggests that the biologic profile of breast tumors may vary with the menstrual cycle and that these variations deserve further study.  相似文献   
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When considering the chances of establishing a healthy ongoing pregnancy after in vitro fertilization (IVF), the cause of infertility plays a relatively minor role. In recent years, there has been a shift from determining the diagnosis to the individual prognosis for a given patient. A number of prognostic factors were identified, which enabled clinicians to appropriately counsel patients. Patient-determined factors are of crucial importance and some are amenable to intervention such as lifestyle and nutritional advice. However, the attention of clinicians remains on seeking adjuvant therapeutic interventions designed to improve the outcomes of IVF treatment. In this article, the patient-determined factors underlying the individual chance of conceiving and the more commonly prescribed empirical medical therapies prescribed to enhance outcomes are reviewed. It is concluded that greater attention to optimizing the health of the couple before starting IVF treatment may be more beneficial than adjuvant medical therapies during treatment.  相似文献   
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