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41.
42.
Haruo Ito Zengo Kataumi Shigeyuki Yanagi Kenji Kawamura Hidenori Sumiya Hideki Fuse Jun Shimazaki 《International journal of andrology》1986,9(3):161-169
Testicular development was studied in prepubertal boys with retractile testes. Testicular volume, the diameter of the seminiferous tubules and the number of spermatogonia in the tubules were decreased in cases of unilateral retractile testis, when compared with values for the contralateral normally descended testis. On the other hand, in patients with a unilateral retractile testis and contralateral inguinal testis, there was no difference in the developmental parameters between the two testes. These results suggest that the retractile testis has developmental failures characteristic of a cryptorchid testis and therefore requires orchiopexy. 相似文献
43.
Summary: The present study was undertaken in the hope that conflicting opinions concerning interrelationships among minimal change disease (MCD), mesangial proliferative glomerulonephritis (MPG) and focal segmental glomeruloscierosis (FSGS) might be elucidated by morphometric methods performed by image analysis, as well as to study whether serum creatinine and changes in quantitatively analysed glomeruli could correlate with the interstitial fibrosis in these glomerulopathies. Fifteen renal biopsy specimens from children with MCD, 10 with primary MPG and 12 with FSGS for whom both light and electron microscopy as well as immunofluorescence microscopy and full clinical data were available, were examined quantitatively. As a control five biopsy and 10 autopsy specimens of the normal kidneys were used. Our quantitative study showed that in MCD, MPG and FSGS glomerular and interstitial values differed from normal. Morphometric differences between MPG and both MCD and FSGS groups were also shown. Although the mean values of total glomerular area and relative interstitial volume were increased in FSGS patients, in total glomerular cells per unit of glomerular area and mesangium (% of total glomerular area) were similar in both MCD and FSGS groups. In MPG strong positive correlations existed between interstitial volume and serum creatinine, interstitial volume and total glomerular cells per unit of glomerular area as well as between interstitial volume and glomerular mesangium (% of total glomerular area). In FSGS there was significant positive correlation between interstitial volume and serum creatinine. In the MCD group all correlations were weak and not significant. In conclusion, our morphometric studies suggest a close relationship between MCD and FSGS, and indicate that MPG is a separate morphologic entity in children. 相似文献
44.
The glomerular capillary wall imposes a remarkably efficient barrier to the passage of proteins the size of albumin and larger. The development of heavy proteinuria signifies impairment of the function of this barrier. Because endogenous proteins of graded size are heterogeneous with respect to their molecular charge and undergo extensive tubular reabsorption, they are not useful for quantifying the extent of barrier dysfunction. An alternative approach is to determine the fractional clearance of uncharged and non-reabsorbable polymers of graded size. When combined with a hydrodynamic theory of solute transport through a heteroporous membrane, the intrinsic properties of healthy and diseased glomerular capillary walls can be inferred. This approach reveals the nephrotic range proteinuria that attends minimal change nephropathy to be associated with impairment of both the size- and charge-selective properties of glomerular capillary walls. 相似文献
45.
Tetsuo Ohta Takukazu Nagakawa Hiroshi Itoh Luis Fonseca Itsuo Miyazaki Tadashi Terada 《Journal of gastrointestinal cancer》1993,14(3):283-289
Summary We present a serous cystadenoma of the pancreas with focal malignant changes, and describe its characteristic histological
features. On gross examination, a tumor was present on the anterior surface of the body of the pancreas and measured approx
25×25⋻20, mm. Microscopically, most tumor cells showed the typical histological features of serous cystadenoma, characterized
by a microcystic architecture and glycogenrich cells with a uniform and bland appearance. However, in some areas, a tendency
to papillary structures with fibrovascular cores was noted. These papillary lesions were composed mainly of nonmucinous, glycogen-poor
epithelial cells, the nuclei of which showed a mild atypia. In addition, vascular and perivascular invasion was focally observed.
However, there was no clinical evidence of local or distant metastasis. From these findings, we diagnosed this lesion as a
serous cystadenoma of the pancreas with focal malignant changes rather than a serous cystadenocarcinoma of the pancreas. 相似文献
46.
47.
脑出血患者血肿周围组织病理及超微结构变化的动态观察 总被引:12,自引:2,他引:10
目的观察脑出血患者血肿周围组织普通病理及超微结构的动态变化。方法对30例脑出血患者采取非功能区人颅直视手术,清除血肿前于血肿旁约1cm处取少许脑组织作为实验组,按发病到手术的时间分为6h以内组6例,6~12h组7例,12~24h组5例,24~48h组3例,48~72h组3例,3~4d组3例,5d组2例,8d组1例。从12h以内组中的7例患者于手术入颅路径上远离血肿处取少许脑组织作为对照组。应用光镜_硐J电镜观察脑组织普通病理及超微结构的动态变化。结果对照组脑组织形态和结构基本正常。实验组6h以内脑组织有轻微损伤。6h以后脑组织损伤逐渐加重。24~48h损伤达高峰,光镜显示脑细胞和纤维水肿明显,细胞形态不完整,核固缩,炎性细胞侵润明显;电镜显示神经元细胞核变空染色质聚集,线粒体肿胀,嵴变短或消失,核糖体减少,次级溶酶体增加,细胞变空,细胞膜不完整,胶质细胞核固缩。72h以后损伤逐渐好转,5d时损伤与6~12h组相似,8d时基本好转,与6h以内组基本接近。结论脑出血后血肿周围脑组织继发性损伤早期就有病理改变,损伤高峰在24~72h,与一般脑出血临床神经功能损害的变化规律基本一致。 相似文献
48.
Modic changes following lumbar disc herniation 总被引:4,自引:3,他引:1
Only a small proportion (20%) of patients with LBP can be diagnosed based on a patho-anatomical entity. Therefore, the identification
of relevant subgroups, preferably on a patoanatomical basis, is strongly needed. Modic changes have been described by several
authors as being closely linked with LBP. The aims of this study were to describe the prevalence of Modic changes, their development
as well as their association to LBP, previous disc contour, and surgery in patients with previous severe sciatica. This is
a longitudinal cohort study where the patients were recruited from an RCT comparing two active conservative treatments, the
181 patients, who at baseline had radicular pain in or below the knee; all underwent a physical examination and MRI. MRI’s,
pain history and physical examination of 166 patients were obtained at follow-up 14 months later. The prevalence of Modic
changes type 1 increased from 9% at baseline to 29% at follow-up. At that time, a strong association between Modic changes
and non-specific LBP was noted. Apparently, Modic changes type 1 was more strongly associated with non-specific lumbar pain
than Modic changes type 2. The development of new Modic changes was closely related to the level of a previous disc herniation.
A lumbar disc herniation is a strong risk factor for developing Modic changes (especially type 1) during the following year.
Furthermore, Modic changes are strongly associated with LBP. 相似文献
49.
Rosenberg Leonard S. Hostetler Cheryl K. Wagenknecht Dietmar M. Aunet Diane A. 《Pharmaceutical research》1988,5(8):514-517
Esmolol hydrochloride degrades in aqueous solutions by the hydrolysis of a labile aliphatic carboxy-ester group. The products are methanol and ASL-8123. The resulting aliphatic carboxylic acid moiety (ASL-8123) has a pK of 4.80, which is within 1 pH unit of the pH of the formulation. ASL-8123 therefore acts as a secondary buffer and minimizes the change in pH due to degradation. Equations are presented to calculate the change in the pH when the primary degradation product acts as a secondary buffer. This information can be used in the development of a parenteral product to predict, a priori, the concentration of buffer necessary for optimal pH maintenance. This knowledge can reduce the number of formulation screens required to determine the necessary buffer capacity for optimal drug stability. 相似文献
50.
目的 探讨清创换药、负压引流、富血小板血浆治疗的创基准备程序性治疗在慢性难愈性创面中的效果。方法 回顾性分析2017年5月—2021年5月江南大学附属医院收治的83例创基准备程序性治疗的慢性难愈性创面患者的临床资料,根据治疗方法不同分为清创换药组25例、负压引流组35例、富血小板血浆组23例。比较3组患者创面愈合时间、创面完全愈合患者占比,临床疗效,治疗前后视觉模拟疼痛评分(VAS)差值、温哥华瘢痕评定量表(VSS)评分,治疗前后创面感染指标差值,创面细菌阳性率及复发情况。结果 富血小板血浆组创面愈合时间短于清创换药组和负压引流组(P <0.05),富血小板血浆组与清创换药组和负压引流组创面完全愈合患者占比比较,差异无统计学意义(P>0.05);富血小板血浆组与清创换药组和负压引流组总有效率比较,差异无统计学意义(P>0.05);富血小板血浆组治疗前后VAS评分差值高于清创换药组和负压引流组(P <0.05),富血小板血浆组VSS评分低于清创换药组和负压引流组(P <0.05);富血小板血浆组治疗前后C反应蛋白差值、白细胞计数差值均高于清创换药组和负压引流... 相似文献