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81.
OBJECTIVES: Most of our knowledge concerning renal obstruction has been derived from experimental animal models, and it is not yet well defined in spontaneous hydronephrosis. The aim of our study is to evaluate the roles of transforming growth factor-beta1 (TGF-beta1) and apoptosis in congenital hydronephrotic kidneys in comparison with experimental models. METHODS: We made histological studies on kidneys from 6-week-old Wistar-Imamichi rats with congenital unilateral hydronephrosis as well as surgical models of complete or partial unilateral ureteral obstruction. The severity of hydronephrotic kidneys was evaluated on routine hematoxylin and eosin (H&E) stained sections, and the tubulointerstitial fibrosis analyzed morphometrically on Masson's trichrome stained sections. Renal tubular atrophy was assessed on periodic acid Schiff (PAS) stained sections, and tubular cell apoptosis assessed with TUNEL technique. The renal TGF-beta1 level was determined by a sandwich enzyme-linked immunosorbent assay (ELISA). RESULTS: We observed a significant loss of kidney weight with profound compensatory growth of the contralateral kidney in rats with congenital hydronephrosis. Most of the hydronephrotic kidneys were markedly enlarged with dilatation of the collecting system, renal parenchymal thinning, tubular atrophy, interstitial infiltration and fibrosis. The renal TGF-beta1 level was markedly elevated in hydronephrotic kidneys as compared with normal controls (326.01 +/- 30.64 pg/mg protein vs 227.81 +/- 11.07 pg/mg protein, P < 0.01). The tubular apoptotic score in hydronephrotic kidneys was also significantly higher than normal controls (2.17 +/- 0.50/HPF [high power field]vs 0.14 +/- 0.04/HPF, P < 0.01). The increased TGF-beta1 and apoptotic status paralleled the histological changes of tubulointerstitial fibrosis and tubular atrophy. Similar findings were also obtained in experimental obstructive models. CONCLUSION: In comparison with surgical models of partial and complete ureteral obstruction, our data provide solid morphological and molecular evidences of renal obstruction in rats with congenital hydronephrosis.  相似文献   
82.
Stereoisomers of cyclo(Gly-Pro-Phe-Ala-Asn-Ala-Val-Ser) were synthesized. NMR studies of their solution conformations, focusing on peptide N-H solvent exposure, were made. These indicated that a single proline residue in the cyclic octapeptide ring is insufficient constraint to stabilize the backbone conformations that were previously established for cyclo(Gly-Pro-Phe-Ala)2.  相似文献   
83.
The purpose of this study was to compare rubidium-82 PET withthallium-201 SPECT imaging in 150 patients. Both techniquesfollowed a single dipyridamole-handgrip stress, and images weredisplayed using the same 3-dimensional format and quantitativecolour scale. Coronary arteriography was employed to assignthe correct diagnosis in situations of disparity. Results of PET and SPECT were at least partially concordantin 110 patients (73%), although 22 had more than one defect.A reversible perfusion defect was identified in 60 patients,but the scans were concordant in only 20 (33%). These disparitieswere chiefly due to false-negative SPECT imaging (22 patients,55%), and probable delayed thallium redistri bution (13 patients,33%). No patients had ischaemia correctly identified by SPECTin the presence of normal PET imaging. Persistent defects wereidentified in 91 patients, some of whom also had reversibledefects, and the results were consistent in 54 (59%). Otherthan the delayed thallium redistribution group, the major categoriescausing disparities were false-positive (6 patients, 16%), andfalse negative SPECT (8 patients, 22%), attributable to attenuationand scatter. PET appears able to identify smaller, less ischaemic areas subtendedby milder coronary stenoses. The availability of a true restingscan with Rb-PET enhances the discrimination between ischaemiaand infarction. Attenuation correction, and the high energyphotons of positron annihilation, yield more accurate evaluationof inferior wall defects and greater specificity in the presenceof soft tissue attenuation.  相似文献   
84.
改良第二掌背动脉皮瓣修复示中指中末节套脱伤   总被引:3,自引:2,他引:1  
Objective To investigate the operative procedure and the clinical results of the modified reversed island flap based on the second dorsal metacarpal artery (SDMA) for repairing index or long finger degloving defects.Methods From May 2004 to January 2010, circumferential soft tissue defect in the middle and distal phalanx of the index or long fingers in 17 patients were repaired by the modified reversed island flaps based on SDMA.The dorsal digital nerve in the flap was coapted to the severed proper digital nerve.The area of the flaps ranged from 2.5 cm × 5.6 cm to 5.0 cm × 6.5 cm.The donor sites were closed by skin graft.Results Postoperatively blister and necrosis of the distal flap occurred in 2 cases which was cured by dressing change.All the other flaps survived uneventfully.Primary healing of the flaps and donor sites was achieved.All 17 patients were follow-up for 4 to 27 months with an average of 15.3 months.The flaps were pliable, full but not bulky.Two-point discrimination was 7 to 11 mm (mean 8.6 mm).Hand function as judged by the total active range of motion of the fingers was excellent in 8 fingers, good in 7 fingers and fair in 2 fingers.The satisfactory rate was 88.2%.Conclusion Modified SDMA reversed island flap transfer with dorsal digital nerve coaptation is an ideal procedure to repair index or long finger degloving injuries.The area of the harvested flap is large enough to cover the circumferential soft tissue defect in the middle and distal phalanx.The surgery is safe due to the reliable flap circulation.  相似文献   
85.
目的 探讨简易悬吊术治疗男性尿失禁的疗效.方法 2000年10月-2009年7月上海交通大学附属第六人民医院收治的男性获得性尿失禁患者44例,其中前列腺术后34例,后尿道手术后10例;完全性尿失禁11例,压力性尿失禁33例,每人需尿布1~5块/d,平均(3±1)块/d.43例行心脏涤纶补片和尼龙线+经阴道无张力尿道中段悬吊(TVT)吊带球部尿道复合悬吊术,1例采用经闭孔途径球部尿道悬吊术.结果 随访6~90个月,平均为(52±30)个月.术后初期治愈35例,尿失禁改善7例,手术失败2例,总有效率为95.4%(42/44).术后随访1年以上患者的总有效率为90.0%(36/40),2例分别在术后1年和2年复发.1例采用经闭孔途径球部尿道悬吊术的患者术后随访6个月,能完全控尿,无残余尿.结论 球部尿道悬吊术是治疗男性尿失禁简单而有效的方法.  相似文献   
86.

Background  

The relationship between primary source of income and HIV risk behaviors and the racial/ethnic differences in risk behavior profiles among disadvantaged populations have not been fully explored. This is unusual given that the phenomenon of higher risk in more disadvantaged populations is well-known but the mechanisms remain unclear. We examined the relationship between primary source of income and differences in HIV risk behaviors among four racial/ethnic groups in the southern United States.  相似文献   
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89.
Littlejohn  GO; Brand  CA; Ada  A; Wong  C 《Radiology》1985,155(1):237-240
Thirty-four patients who clinically were suspected of having deep venous thrombosis (DVT) underwent Tc-99m red blood cell (RBC) venography followed by contrast venography. The sensitivity (88%) and specificity (94%) of Tc-99m RBC venography for DVT confirmed findings of previous studies. Twenty-four patients who had proved popliteal cysts and swollen calves also were examined using Tc-99m RBC venography. Large cysts (greater than 9 X 4 X 4 cm) showed lack of DVT features, photon deficient cold areas in the popliteal fossa, and diversion of venous flow around the photon deficient area. These features were seen in 25% of the study population (six patients), and assisted in the distinction between the two conditions.  相似文献   
90.
A systematic study was carried out on mutability of amino acid residues in evolving proteins in relation to their polarity and location within three-dimensional structure of proteins. Exteriority of residue sites is quantitatively defined as accessibility based on their static accessible surface area to solvent water molecule. Residue sites are classified into interior and exterior depending on their accessibility. More frequent substitution on exterior sites is confirmed to be general in eight sets of homologous protein families regardless of their biological functions and of presence or absence of a prosthetic group. Virtually all types of amino acid residues are found to have higher mutabilities on the exterior than in the interior. No correlation between mutability and polarity was observed of amino acid residues in the interior and on the exterior, respectively. Amino acid residues are classified into three depending on their polarity, polar (Arg, Lys, His, Gln, Asn, Asp and Glu), weak polar (Ala, Pro, Gly, Thr and Ser) and nonpolar (Cys, Val, Met, Ile, Leu, Phe, Tyr and Trp). Amino acid replacements during protein evolution are very conservative; 88% and 76% of them in the interior and on the exterior, respectively, are within the same group of the three. Inter-group replacements are such that weak polar residues are replaced more often by nonpolar residues in the interior and more often by polar residues on the exterior.  相似文献   
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