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1.
《The surgeon》2022,20(4):e100-e104
IntroductionUndescended testis (UDT) is a clinical diagnosis and a common reason for referral to paediatric urology outpatients. Our aim was to assess current referral patterns at our unit and to identify predictive factors that may better aid primary care physicians (PCP) in diagnosing UDT based on history and physical exam.MethodsA retrospective analysis of referrals to outpatients from 2014 to 2016 was performed to assess current referral patterns including referral source, age, reason for referral and outcome following assessment by a single consultant paediatric urologist.A prospective analysis of new referrals was performed to identify predictive factors which may aid in the diagnosis of UDT including gestational age, presence of scrotal asymmetry and previously obtained imaging.ResultsFrom 2014 to 2016, 259 boys were referred with suspected UDT. The majority of referrals were received from PCPs (62%) followed by Neonatology (29%), Paediatrics (8%) and general surgery (1%). Median age at time of assessment was 29 (5–180) months. One hundred and eight (41.7%) boys were diagnosed with UDT.There were 74 boys assessed prospectively. Median age at assessment was 24.5 (6–171) months. We identified 3 predictors of a diagnosis of UDT; history of prematurity (p = 0.001), UDT mentioned to the parents at birth (p = 0.027) and scrotal asymmetry on examination (p < 0.001). Greatest diagnostic inaccuracy was found in boys referred beyond one year of age (27.7%). In this cohort, the absence of all three risk factors was associated with a negative predictive value of 94.1%.ConclusionThe majority of boys with suspected UDT are referred beyond the age recommended for orchidopexy (6–12 months). The majority of boys referred for assessment did not have UDT. We have identified three predictive factors that may aid referring physicians when assessing boys, particularly those older than 1 year.  相似文献   
2.
在13只恒河猴精索内注射长效局麻药后,睾丸发生明显变化;而且给药剂量不同,睾丸曲精小管改变的程度和恢复正常的时间亦不同。睾丸间质细胞无明显变化;睾酮分泌不减少,无毒性反应。对临床男性节育应用及生殖生理研究均具有意义。  相似文献   
3.
The Testes in Cadmium Intoxication: Morphological and vascular aspects   总被引:1,自引:0,他引:1  
M. A. Gouveia 《Andrologia》1988,20(3):225-231
Cadmium toxicity was tested on young male Wistar rats by injecting 1 mg/ml of cadmium chloride (CdCl2) intra-peritoneally. Post-mortem examination was done 4 hours, 24 hours and 14 days after cadmium administration to observe time-sequence cadmium-induced alterations in vascular permeability of the mesothelium in the pleura, peritoneum and tunica vaginals. This paper mainly reports the alterations observed in the testes. Vascular permeability was assessed by the colloidal carbon technique. Vascular labelling was evidenced as early as 4 hours after CdCl2, injection; 24 hours later severe oedema with leakage of particles to the interstitium and also into the tubules was patent. Fourteen days after CdCl2 administration atrophy of the testes with necrosis of the tubules, fibrosis of the interstitium and vascular thrombosis was found, compatible with chemical castration.  相似文献   
4.
IntroductionTo evaluate the feasibility of testis diffusion tensor imaging (DTI), to determine normative apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values and to assess the efficacy of DTI in characterizing testicular pathology.Materials and methodsFifty-six men underwent MRI of the scrotum, including DTI. Parametric and non-parametric statistical tests were used to compare the ADC and FA between the cranial, middle and lower thirds of normal testis and between the bilateral testicular thirds. Comparison between the ADC and FA of normal testis, malignant and benign testicular lesions was performed.ResultsNo significant differences of the ADC and FA in normal testis between the cranial, middle and lower thirds and between the bilateral testicular thirds were found. ADC was significantly lower in malignancies compared to normal testis (P = 0.006) and benign testicular lesions (P = 0.006). FA was significantly higher both in malignancies (P = 0.001) and benign lesions (P < 0.001) compared to normal testis. FA in malignancies did not differ from FA in benign lesions (P = 0.221)ConclusionsThis study shows the feasibility of testis DTI. Both ADC and FA significantly differ between testicular lesions and normal testis, although FA did not show an incremental diagnostic value compared to ADC in lesion differentiation.  相似文献   
5.
IntroductionPatients with vestibular hypofunction, a typical finding in peripheral vestibular disorders, show body balance alterations.ObjectiveTo evaluate the postural control of patients with vertigo and unilateral vestibular hypofunction.MethodThis is a clinical cross-sectional study. Twenty-five patients with vertigo and unilateral vestibular hypofunction and a homogeneous control group consisting of 32 healthy individuals were submitted to a neurotological evaluation including the Tetrax Interactive Balance System posturography in eight different sensory conditions.ResultsFor different positions, vertiginous patients with unilateral vestibular hypofunction showed significantly higher values of general stability index, weight distribution index, right/left and tool/heel synchronizations, Fourier transformation index and fall index than controls.ConclusionIncreased values in the indices of weight distribution, right/left and tool/heel synchronizations, Fourier transformation and fall risk characterize the impairment of postural control in patients with vertigo and unilateral vestibular hypofunction.  相似文献   
6.
Zearalenone (ZEA) is a mycotoxin commonly found as a contaminant in cereals. ZEA toxicity targets mainly the reproductive system, and oxidative stress plays an etiological role in its toxic effects. Therefore, the present study aimed to investigate the effect of lycopene, a potent carotenoid antioxidant, on markers of oxidative stress in liver, kidney and testes, and on reproductive, hematological and histopathological parameters after ZEA administration. Adult Swiss albino male mice received lycopene (20 mg/kg, p.o.) for ten days before a single oral administration of ZEA (40 mg/kg, p.o.), and 48 h thereafter tissues (liver, kidney, testes and blood) were collected for biochemical, hematological and histological analyses. Lycopene prevented ZEA-induced changes in hematological parameters (increased number of leukocytes, segmented neutrophils, sticks, eosinophils and monocytes and decreased number of red blood cells (RBC), number of lymphocytes and platelets). Moreover, lycopene prevented the reduction in the number and motility of spermatozoa and the testicular tissue damage induced by ZEA. In addition, lycopene prevented the decrease in glutathione-S-transferase activity in kidney and testes and increased glutathione-S-transferase activity per se in the liver, kidneys and testes as well as superoxide dismutase activity in the liver. In summary, lycopene was able to prevent ZEA-induced acute toxic effects in male mice, suggesting that this antioxidant carotenoid may represent a promising prophylactic strategy against ZEA toxicity.  相似文献   
7.
正常阴囊及其内容物的超声应用解剖   总被引:11,自引:0,他引:11  
器官和组织的病理解剖是超声诊断疾病的客观基础。了解阴囊、睾丸、附睾的正常解剖特征和血管分布特点,是超声诊断这类器官疾病的必要条件。文中指出,睾丸大小形态、血管分布、动脉血流速度和阻力指数、附睾的大小、形态以及阴囊壁厚度等等都是诊断和鉴别诊断的主要线索,同时以大量的图片辅助说明。此外还阐述了应用彩色多普勒超声检查阴囊时如何提高仪器灵敏度,尽可能发现更细微、更全面的病变信息的技术要领。  相似文献   
8.
Analyses of the development of the reproductive system in seasonally breeding birds in the framework of long-term ecological studies are rare. Here, we present the first results of such a study in two Corsican populations of a European passerine bird, the blue tit (Parus caeruleus). The two study populations occupy different oak habitats and are separated by only 25 km. Despite their close proximity, they show a one-month difference in onset of egg laying, even after controlling for altitude. This micro-geographic difference in breeding date appears adaptive because both study populations raise chicks when food is most plentiful. In our study, males reached their maximum song activity during the egg-laying stage while maximal testosterone levels and testes sizes were reached 2-3 weeks before egg laying. The rate of development of the reproductive system in males was much faster in the earlier population, in spite of a similar onset of gonad development and song activity for the two study populations. No change in the volume of the song-control nuclei (HVC and RA) could be detected during the study period. Development of brain nuclei was completed 2-3 months before the beginning of intense sexual activity.  相似文献   
9.

Aim

Fertility post-orchidopexy is dependent on transformation of neonatal gonocytes (G) into adult dark spermatogonia at about 3 months, the same time as gonadotrophins stimulate androgen secretion. We examined how androgen blockade affects transformation of gonocytes to spermatogonial stem cells (SSC) during this period in patients with undervirilisation syndromes.

Methods

Patients with undervirilisation syndromes (n = 30, 1.5 weeks–16 years) underwent review of medical records, pathology reports, and H&E slides of testes (ethics HREC32164). Fluorescent immunohistochemistry against anti-Mullerian hormone (AMH, Sertoli cells), mouse VASA homologue (MVH, germ cells) and DAPI (nuclei) allowed the number of MVH-positive gonocytes/spermatogonial stem cells per seminiferous tubular cross-section (G/T or SSC/T) to be counted.

Results

Gonocytes (MVH-positive cells in the tubular lumen) were present in 15/16 patients under 2 years old. SSC (MVH-positive cells on the tubule basement membrane) were present in 25/30 patients. With increasing age, the mean number of SSC/T decreased from ~ 4 to 0, and G/T decreased from ~ 1.5 to 0. SSC were present in CAIS and PAIS patients at 1.5 and 3.5 weeks old, respectively.

Conclusions

Gonocytes transform into SSC earlier than expected in patients with undervirilisation syndromes. Lack of androgens may stimulate non-androgenic regulators to trigger transformation. Understanding how gonocytes transform may enable optimization of spermatogonial development to preserve fertility post-orchidopexy.  相似文献   
10.
The multidrug resistance-associated protein 1 (MRP1/ABCC1) is a member of the ABC active transporter family that can transport several steroid hormone conjugates, including 17β-estradiol glucuronide, dehydroepiandrosterone sulfate (DHEAS), and estrone 3-sulfate. The present study investigated the role that MRP1 plays in maintaining proper hormone levels in the serum and testes. Serum and testicular steroid hormone levels were examined in both wild-type mice and Mrp1 null mice. Serum testosterone levels were reduced 5-fold in mice lacking Mrp1, while testicular androstenedione, testosterone, estradiol, and dehydroepiandrosterone (DHEA) were significantly reduced by 1.7- to 4.5-fold in Mrp1 knockout mice. Investigating the mechanisms responsible for the reduction in steroid hormones in Mrp1−/− mice revealed no differences in the expression or activity of enzymes that inactivate steroids, the sulfotransferases or glucuronosyltransferases. However, steroid biosynthetic enzyme levels in the testes were altered. Cyp17 protein levels were increased by 1.6-fold, while Cyp17 activity using progesterone as a substrate was also increased by 1.4- to 2.0-fold in mice lacking Mrp1. Additionally, the ratio of 17β-hydroxysteroid dehydrogenase to 3β-hydroxysteroid dehydrogenase, and steroidogenic factor 1 to 3β-hydroxysteroid dehydrogenase were significantly increased in the testes of Mrp1−/− mice. These results indicate that Mrp1−/− mice have lowered steroid hormones levels, and suggests that upregulation of steroid biosynthetic enzymes may be an attempt to maintain proper steroid hormone homeostasis.  相似文献   
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