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31.
Detecting pre-ovulatory luteinizing hormone surges in urine 总被引:2,自引:1,他引:2
Kesner JS; Knecht EA; Krieg EF Jr; Wilcox AJ; O'Connor JF 《Human reproduction (Oxford, England)》1998,13(1):15-21
The study objectives were to determine (i) if pre-ovulatory luteinizing
hormone (LH) surges, undetected in urine by two immunoradiometric assays
(IRMA), were detectable by an ultrasensitive immunofluorometric assay
(IFMA) and (ii) the influence of creatinine adjustment on the detection and
timing of the urinary LH surges. Daily urine specimens were contributed by
healthy 25-36 year old volunteers during 14 ovulatory menstrual cycles for
an epidemiological study conducted in 1983-1985. Specimens were selected as
having been previously assayed by two IRMA without consistently detecting
LH surges. These urine specimens were remeasured using an IFMA and adjusted
for creatinine concentration. IFMA measurements revealed unambiguous LH
surges in all cycles. Adjusting IRMA urinary LH values for creatinine
concentrations revealed previously undetected LH surges in four of eight
cycles. Creatinine adjustment also altered the timing of IRMA and IFMA LH
surges by 1-5 days. These results demonstrate an IFMA that detects pre-
ovulatory LH surges in unpreserved, frozen urine from cycles where such
surges were previously undetectable. Further, creatinine adjustment can
markedly affect detection and timing of the onset and peak of the urinary
LH surge. While our analysis suggests that this adjustment improves the
validity of the LH measure, this requires further investigation.
相似文献
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33.
Poor development of outer dense fibers as a major cause of tail abnormalities in the spermatozoa of asthenoteratozoospermic men. 总被引:2,自引:0,他引:2
For a reasonable analysis of sperm motility, consideration should be given to the morphology of the flagellum. Among various tail disturbances, the present paper describes a structural shaft defect that is characterized by variations in diameter, poor outline and/or lacking endpiece. Electron microscopical examinations, especially the negative staining technique, have shown that in addition to membrane alterations there is one essential cause for the limited extension of the outer dense fibres. This disturbance may be of genetic origin or due to toxic or inflammatory influences. Further molecular biological studies are required to detect the actual cause of this defect, for which there is so far no adequate therapy. 相似文献
34.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
35.
Infertility is a major health issue affecting over 48.5 million couples around the world, with the male factor accounting for about 50% of the cases. The conventional semen analysis recommended by the World Health Organization (WHO) is the cornerstone in the evaluation of male fertility status. It includes macroscopic and microscopic evaluation of the ejaculate, which reflects the production of spermatozoa in the testes, the patency of the duct system and the glandular secretory activity. Evaluation of seminal fructose, sperm vitality and leucocytes (Endtz test) are useful adjuncts to semen analysis that provide information on specific clinical conditions. Though several computer-assisted sperm analysis (CASA) systems have been developed, conventional methods for semen analysis are still widely accepted in clinical practice. This review summarises the conventional techniques used in routine semen analysis and their diagnostic value in clinical andrology. 相似文献
36.
Varicocele is one of the major causes of male infertility and has a negative impact on spermatogenesis. The conventional semen analysis does not reveal the underlying subcellular mechanisms associated with defects in spermatozoa. Proteomics and bioinformatics analysis can be used to identify the molecular aetiologies associated with poor semen quality in varicocele patients. Mitochondrial dysfunction has been identified as the main factor affecting normal physiological functions of spermatozoa. This article discusses the proteomic studies of spermatozoa and seminal plasma in varicocele patients. Proteomics can identify potential spermatozoa and seminal plasma biomarkers in varicocele-mediated male infertility. In future, these protein biomarkers can be useful in the development of noninvasive diagnostic and therapeutic strategies for varicocele patients. 相似文献
37.
Haitham Elbardisi Ahmad Majzoub Christiana Daniel Fadwa Al.Ali Mohamed Elesnawi Kareim Khalafalla Ashok Agarwal Ralf Henkel Alia Alattar Ibrahim Al-Emadi Mohamed Arafa 《Andrologia》2021,53(8):e14135
In this study, we investigated the prevalence of sexual dysfunction among males with advanced chronic kidney disease and the effect of treating hyperprolactinemia among these patients. In this prospective study, patients were assessed with history, physical examination, hormonal assessment, and two questionnaires, IIEF and AIPE. Patients with hyperprolactinemia received treatment with cabergoline 0.5 mg once per week for 6 months and were re-evaluated. A total of 102 patients were included in this study, 75 (73.53%) were on hemodialysis, 13 (12.75%) on peritoneal dialysis and 14 (13.73%) on medical treatment alone. Ninety (88.24%) patients had premature ejaculation, 85 (83.33%) had anything from mild-to-moderate-to-severe erectile dysfunction. The incidence of hypogonadism and hyperprolactinemia was 34.4%. Patients treated with cabergoline (n = 26) showed a significant increase in LH levels (p = .003) and a significant decrease in prolactin levels (p = .003). Testosterone levels and the incidence of erectile dysfunction or premature ejaculation did not improve significantly. There is a high incidence of sexual dysfunction among patients. Treatment of hyperprolactinemia is effective in correcting prolactin levels, but does not improve erectile dysfunction or premature ejaculation. Therefore, treating hyperprolactinemia is not an overall effective treatment for erectile dysfunction in these patients. 相似文献
38.
JS Tsang Chi Chung Foo Jeremy Yip Hok Kwok Choi Wai Lun Law Oswens Siu Hung Lo 《The surgeon》2021,19(3):150-155
IntroductionThe difference in outcome between right (RCD) and left colonic diverticulitis (LCD) is not well established. The aim of this study was to analyse the presentation and surgical outcome of RCD versus left-sided disease following emergency surgery.MethodWe conducted a retrospective review of patients presenting with acute diverticulitis over a 10-year period from 2004 to 2014 to a tertiary unit. Patient demographics, Hinchey classification, need for emergency surgery, perioperative outcome and recurrence were evaluated.ResultsIn total 360 patients presented with acute diverticulitis, 218 (61%) were right-sided and 142 (39%) were left-sided. The mean age (57 yrs vs 68 yrs) and median length of stay (4 days vs 5 days) were significantly less in RCD (p < 0.001). The need for emergency surgery was similar between RCD and LCD (30.7% vs 23.2%, p = 0.12). Sixty-seven (31%) patients with RCD required emergency surgery, 42 (62.7%) of these were based on a presumptive diagnosis of appendicitis and underwent laparoscopic appendicectomy only. Operative morbidity (10.4% vs 51.5%, p < 0.001) and mortality were significantly higher in LCD (1.5% v 15.2%, p = 0.007). Subgroup analysis of non-appendicectomy, RCD patients, showed LCD were more likely to require surgery (11.5% vs 23.2%, p = 0.003). There was no difference in recurrence (p = 0.6).ConclusionRight colonic diverticulitis patients are younger and disease course is more benign compared to LCD. Presentation can be confused with appendicitis without proper imaging. In the rare cases where emergency surgery is required, RCD is associated with a lower operative morbidity and mortality compared to left-sided disease. 相似文献
39.
40.
0 引言 人类免疫缺陷病毒 (human immunodeficiencyvirus,HIV) - 1编码的反式激活蛋白 TAT具有独特的跨膜运转方式 ,而且有转导速度快 ,效率高的特点 ,被称为蛋白转导结构域 (protein transduction domain,PTD) [1 ,2 ] .本研究用PCR扩增了慢性粒细胞白血病慢粒 bcr/ abl融合蛋白的基因片段 ,在其 5′端融合 PTD结构域的编码区后在大肠杆菌中进行了表达 .表达产物经纯化后 ,加入培养的 HL 6 0细胞 ,表达的蛋白可直接进入细胞内 .这一结果为用外源蛋白负载(L oading)免疫细胞提供了新的途径 .1 材料和方法1.1 DNA重组 人工合… 相似文献