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991.
992.
993.
An interpretation of previous and recent observation on calcium salt crystallization and calcium stone formation provide the basis for formulation of a hypothetical series of events leading to calcium oxalate (CaOx) stone formation in the urinary tract. The various steps comprise a primary precipitation of calcium phosphate (CaP) at high nephron levels, establishment of large intratubular and/or interstitial (sub-epithelial) aggregates of CaP. These crystal masses subsequently might be dissolved during periods with low urine pH. On the denuded surface of subepithelial or intratubularly trapped CaP, release of calcium ions can result in very high ion-activity products of CaOx, particularly during simultaneous periods with peaks of CaOx supersaturation. Crystals of CaOx may result from nucleation in the macromolecular environment surrounding the apatite crystal phase. In the presence of low pH, low citrate and high ion-strength of urine, formation of large CaOx crystal masses can be accomplished by self-aggregation of Tamm–Horsfall mucoprotein. Following dislodgment of the initially fixed CaOx stone embryo, the further development into to clinically relevant stone is accomplished by CaOx crystal growth and CaOx crystal aggregation of the retained stone material. The latter process is modified by a number of inhibitors and promoters present in urine. The retention of the stone is a consequence of anatomical as well as hydrodynamic factors.  相似文献   
994.
Channel transurethral resection of prostate (TURP) is an accepted treatment for advanced carcinoma of prostate (CaP) to improve quality of life. We are presenting a case of penile gangrene and urethrocutaneous fistula following TURP in a CaP. This is the first case in literature to our knowledge.  相似文献   
995.
Chou YH  Su CM  Li CC  Liu CC  Liu ME  Wu WJ  Juan YS 《Urological research》2011,39(4):283-287
The prevalence and incidence of urinary stone disease have been reported to be associated with body weight and body mass index (BMI). The aim of the study was to determine the difference in stone components among different BMI groups in patients with urolithiasis. Between Dec 2005 and Jan 2008, 907 urinary calculi were collected and analyzed by infrared spectroscopy. Most of the stones had been passed spontaneously, and some were collected during surgical manipulations. The data on patients’ gender, age, BMI at diagnosis, and stone composition were collected. The patients were classified as normal weight (18.5≤ BMI <24), overweight (24≤ BMI <27), or obese (BMI ≥27). Of the 907 patients with urinary stone disease, 27.7% had normal weight, 33.5% were overweight, and 38.8% were obese. The prevalence of calcium oxalate stones in the normal weight, overweight, and obese groups were 23.1, 30.6, and 34.9%, respectively (P = 0.002), and the prevalence of uric acid stones in the different groups was 2.8, 7.2, and 7.7%, respectively (P = 0.002). The prevalence of calcium oxalate and uric acid stones, but not that of calcium phosphate stones, increased with body size. There was a significant correlation between BMI and uric acid stones in the overweight and obesity groups, with odds ratios of 3.28 and 4.35, respectively. The prevalence and incidence of urinary stone disease were found to be associated with BMI. The percentage of uric acid and calcium oxalate stones was higher in obese than in non-obese patients. There was no apparent difference in the prevalence of calcium phosphate stones between obese and non-obese patients.  相似文献   
996.

Background  

Cardiac arrest during spine surgery in the prone position is difficult to manage as poor access makes cardiopulmonary resuscitation and defibrillation difficult. Advanced age is the maximal risk factor for cardiac arrest. Therefore, we wanted to determine the relationship between age and cardiac risk factors/pre-operating tests for cervical spine surgery in the prone position.  相似文献   
997.
Propagation of short pulses of light through biological tissues can be studied by numerically solving the diffusion equation. The boundary integral method was used to convert the differential equation to integral form and the result was solved using the boundary element method. The effects of different optical parameters of the tissue, i.e. scattering, absorption coefficients and anisotropic factor, on temporal evolution of the diffusely reflected pulse were studied. The results were compared with those obtained using the finite difference time domain method and the boundary integral method was found to be more precise and faster than the last method. The method can be used to investigate reflected pulses in the study of cell morphology and tumours in different types of tissue.  相似文献   
998.

Background  

This retrospective study compares the results of primary gastric bypass (PGB) versus secondary gastric bypass (SGB) performed after gastroplasty.  相似文献   
999.
The aim of this study was to assess structural indices from high-resolution peripheral quantitative computed tomography (HR-pQCT) images of the human proximal femur along with areal bone mineral density (aBMD) and compare the relationship of these parameters to bone strength in vitro. Thirty-one human proximal femur specimens (8 men and 23 women, median age 74 years, range 50–89) were examined with HR-pQCT at four regions of interest (femoral head, neck, major and minor trochanter) with 82 μm and in a subgroup (n = 17) with 41 μm resolution. Separate analyses of cortical and trabecular geometry, volumetric BMD (vBMD), and microarchitectural parameters were obtained. In addition, aBMD by dual-energy X-ray absorptiometry (DXA) was performed at conventional hip regions and maximal compressive strength (MCS) was determined in a side-impact biomechanical test. Twelve cervical and 19 trochanteric fractures were confirmed. Geometry, vBMD, microarchitecture, and aBMD correlated significantly with MCS, with Spearman’s correlation coefficients up to 0.77, 0.89, 0.90, and 0.85 (P < 0.001), respectively. No differences in these correlations were found using 41 μm compared to 82 μm resolution. In multiple regression analysis of MCS, a combined model (age- and sex-adjusted) with aBMD and structural parameters significantly increased R 2 values (up to 0.90) compared to a model holding aBMD alone (R 2 up to 0.78) (P < 0.05). Structural parameters and aBMD are equally related to MCS, and both cortical and trabecular structural parameters obtained from HR-pQCT images hold information on bone strength complementary to that of aBMD.  相似文献   
1000.
目的 探讨原癌基因Ets-1在前列腺组织中的表达及其与前列腺癌组织学分级的关系.方法 利用免疫组化法检测Ets-1在4例正常前列腺组织,12例良性前列腺增生组织和53例前列腺癌组织中的表达.结果 Ets-1蛋白的阳性表达在前列腺癌细胞的胞浆及胞核内均可见,79%的前列腺癌组织中Ets-1呈阳性表达,而在良性前列腺组织细胞中无表达或仅有微弱表达,差异有显著性意义(P<0.05).在前列腺癌组织中,Gleason评分高危组Ets-1阳性表达率明显高于Gleason中危组和低危组(P<0.05).结论 与良性前列腺组织对照相比,Ets-1有肿瘤特异性,其表达与前列腺癌的组织学分级相关,可作为前列腺癌病变程度及临床预后判断的一个分子标志.  相似文献   
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