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51.
Detecting pre-ovulatory luteinizing hormone surges in urine   总被引:2,自引:1,他引:2  
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   
52.
In our previous study, we demonstrated that immobilization stress blocked estrogen-induced luteinizing hormone (LH) surge possibly by inhibiting the synthesis and release of gonadotropin-releasing hormone (GnRH) at the hypothalamic level and by blocking estrogen-induced prolactin (PRL) surge by increasing the synthesis of dopamine receptor at the pituitary level in ovariectomized rats. The present study was performed to determine whether immobilization stress affects pituitary LH responsiveness to GnRH, and whether endogenous opioid peptide (EOP) and dopamine systems are involved in blocking LH and PRL surges during immobilization stress. Immobilization stress was found to inhibit basal LH release and to completely abolish LH surge. However, the intravenous application of GnRH agonist completely restored immobilization-blocked LH surge and basal LH release. Treatment with naloxone did not exert any effect on immobilization-blocked LH surge but increased basal LH release during immobilization stress. Pimozide did not affect immobilization-blocked LH surge or basal LH release. Naloxone also decreased immobilization-induced basal PRL release, but had no effect on immobilization-blocked PRL surge. Immobilization-increased basal PRL levels were augmented by pimozide treatment and immobilization-blocked PRL surge was dramatically restored by pimozide. We conclude that immobilization stress does not impair pituitary LH response to GnRH, and that the immobilization stress-induced blockage of LH surge is probably not mediated by either the opioidergic or the dopaminergic system. However, immobilization-blockade of PRL surge may be partly mediated by the dopaminergic system.  相似文献   
53.
Mucormycosis is a rare but invasive opportunistic fungal infection with increased frequency during chemotherapy-induced neutropenia. The clinical infections due to Mucor include rhinocerebral, pulmonary, cutaneous, gastrointestinal and disseminated diseases. The first two are the most common diseases and all entities are associated with a high mortality rate. Still hepatic involvement of Mucor is rarely reported. We experienced a case of hepatic and small bowel mucormycosis in a 56-year-old woman after induction chemotherapy for B-cell acute lymphocytic leukemia. Initial symptoms were a high fever unresponsive to broad spectrum antibiotics and pain in the left lower abdominal quadrant. It was followed by septic shock, deterioration of icterus and progressively elevated transaminase. An abdominal CT demonstrated multiple hypodense lesions with distinct margins in both lobes of liver and pericolic infiltration at small bowel and ascending colon. Diagnosis was confirmed by biopsy of the liver. The histopathology of the liver showed hyphae with the right-angle branching, typical of mucormycosis. The patient was managed with amphotericin B and operative correction of the perforated part of the small bowel was performed. However, the patient expired due to progressive hepatic failure despite corrective surgery and long-term amphotericin B therapy.  相似文献   
54.
Park YK  Galik J  Ryu PD  Randic M 《Neuroscience letters》2004,361(1-3):220-224
The activation of group I metabotropic glutamate receptors (mGluRs) produces a long-term potentiation of sensory transmission in the substantia gelatinosa (SG) region of the spinal cord (Prog. Brain Res. 129 (2000) 115). The mechanism(s) responsible for the induction of this potentiation is not known. Using rat spinal cord slice preparation and patch-clamp recordings, here we show, that the activation of the group I mGluRs by (S)-3,5-dihydroxyphenylglycine (DHPG, 1 microM), the mGluR1/5 agonist, increased the frequency of both activity-dependent spontaneous EPSCs, and activity-independent miniature EPSCs (mEPSCs). However, DHPG did not affect amplitude of mEPSCs. The effects of DHPG were not seen in the presence of the preferential mGluR1 antagonist CPCCOEt (10 microM). On the other hand, 2-methyl-6-(phenylethynyl)-pyridine (10 microM), a selective mGluR5 antagonist, blocked the DHPG facilitation present during the wash-out of the drug. This novel facilitating effect of the group I mGluR activation on glutamate release is the first report of a direct facilitatory action of both mGluR1 and mGluR5 subtypes on sensory transmission in the spinal cord SG region. These results indicate the potential contribution of synaptic activation of these facilitatory autoreceptors in plasticity of primary afferent neurotransmission.  相似文献   
55.
This study examined the prevalence and correlated factors of cigarette smoking in a cross-sectional, epidemiological survey of Korean American men living in Maryland (n=333). In this sample, 26.1% were current smokers and 42.3% were former smokers. The older age group (> or = 40 years) was more likely to have quit smoking than the younger age group (< 40 years). In multiple logistic regression analysis, acculturation was associated with smoking status; those who stayed more than 20 years in the U.S. were less likely to be current smokers (OR=0.32, 95% CI 0.13-0.77) than those who stayed less than 10 years. Alcohol use was associated with smoking status; those who consumed alcohol were more likely to be current smokers (OR=5.24, 95% CI 2.33-11.79) or former smokers (OR=5.45, 95% CI=2.69-11.04) than those did not. Those with hypertension were more likely to have quit smoking (OR=3.11, 95% CI=1.33-7.24). The results suggest that the role of acculturation in smoking status among Korean American men deserves further attention by researchers as well as by health professionals who develop smoking prevention and cessation programs.  相似文献   
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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   
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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   
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