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2.
The plasma catecholamine stress response is characteristic for a given animal over a one-year period
The same male and female rats with indwelling jugular catheters were stressed (immobilization) on two occasions at the ages of 3 to 4 and 15 to 16 months. Plasma levels of the catecholamines (CA) norepinephrine (NE) and epinephrine (E) were determined before and during stress at each session. During stress, plasma NE and E levels increased markedly. At the younger age, female animals showed markedly higher CA levels than male animals. After one year, stress CA levels were higher for both sexes, but had increased markedly in male and little in female animals. A positive correlation was found between the plasma CA stress response of individual animals at both sessions; this correlation was stronger for males and NE. This indicates that "high" responders usually remain high responders, "low" responders remain low and intermediate responders intermediate. In conclusion, the plasma CA stress response increases markedly in male, but little in female rats over the period of 1 year and the relative magnitude of the individual stress response remains a characteristic of each given animal. 相似文献
3.
Enzyme Immunoassay Detecting Teichoic and Lipoteichoic Acids versus Cerebrospinal Fluid Culture and Latex Agglutination for Diagnosis of Streptococcus pneumoniae Meningitis 下载免费PDF全文
Kristin Stuertz Imke Merx Helmut Eiffert Erich Schmutzhard Michael Mder Roland Nau 《Journal of clinical microbiology》1998,36(8):2346-2348
A newly developed enzyme immunoassay (EIA) was used to detect the presence of pneumococcal teichoic and lipoteichoic acids in cerebrospinal fluid (CSF) from patients with Streptococcus pneumoniae meningitis who were being treated with antibiotics. All initial CSF samples, which on culture grew S. pneumoniae, were positive in the EIA. A total of 14 subsequent culture-negative samples gave clear signals in the EIA up to day 15 after the onset of antibiotic treatment. For 11 CSF specimens, culture, microscopy, and latex agglutination were negative while the EIA detected pneumococcal antigens. The EIA did not react either with CSF of patients with meningitis caused by bacteria other than S. pneumoniae or by viral pathogens. In conclusion, this EIA can be a valuable tool for the diagnosis of S. pneumoniae meningitis from CSF samples in cases in which prior antimicrobial therapy minimizes the usefulness of culture or other antigen detection tests. 相似文献
4.
Amygdala-prefrontal coupling depends on a genetic variation of the serotonin transporter 总被引:12,自引:0,他引:12
Heinz A Braus DF Smolka MN Wrase J Puls I Hermann D Klein S Grüsser SM Flor H Schumann G Mann K Büchel C 《Nature neuroscience》2005,8(1):20-21
Major depression is conditionally linked to a polymorphism of the human serotonin transporter gene (SLC6A4). During the presentation of aversive, but not pleasant, pictures, healthy carriers of the SLC6A4 short (s) allele showed stronger activation of the amygdala on functional magnetic resonance imaging. s carriers also showed greater coupling between the amygdala and the ventromedial prefrontal cortex, which may contribute to the abnormally high activity in the amygdala and medial prefrontal cortex seen in major depression. 相似文献
5.
Veltman I van Asseldonk M Schepens M Stoop H Looijenga L Wouters C Govaerts L Suijkerbuijk R van Kessel A 《Cancer Genetics and Cytogenetics》2002,136(1):17-22
Cytogenetic analysis of peripheral lymphocytes of an infantile patient with a sacral teratoma revealed a constitutional translocation (12;15)(q13;q25) pat. The same translocation was found in four additional relatives. Loss of heterozygosity analysis of the patient's tumor material showed retention of both translocation-derived chromosomes. Since allelic loss in the 12q13 region has been observed in germ cell tumors, we hypothesize that disregulation of genes located at or near the 12q13 breakpoint may be related to the development of this sacral teratoma. As a first step towards the identification of these genes, a 12q13 genomic contig that spans the breakpoint has been constructed. 相似文献
6.
Primary visual cortex contains functional maps of a number of stimulus properties including ocular dominance, orientation, direction, color, and spatial frequency. These maps must be organized with respect to each other and to a single continuous retinotopic map of visual space such that each stimulus parameter is represented at each point in space. In the ferret, geniculo-cortical inputs to cortical layer IV are segregated into ON- and OFF-center patches, suggesting the possibility that there might be an additional cortical map in this species. We have used optical imaging of intrinsic signals to search for ON-OFF maps in ferret visual cortical cells and have found none. This suggests that the high degree of ON-OFF segregation seen subcortically in the ferret may play a role in the development of visual cortical receptive fields rather than in adult cortical function. 相似文献
7.
Carlos R Ferreira Dillon Kavanagh Ralf Oheim Kristin Zimmerman Julian Stürznickel Xiaofeng Li Paul Stabach R Luke Rettig Logan Calderone Colin MacKichan Aaron Wang Hunter A Hutchinson Tracy Nelson Steven M Tommasini Simon von Kroge Imke AK Fiedler Ethan R Lester Gilbert W Moeckel Björn Busse Thorsten Schinke Thomas O Carpenter Michael A Levine Mark C Horowitz Demetrios T Braddock 《Journal of bone and mineral research》2021,36(5):942-955
Inactivating mutations in human ecto-nucleotide pyrophosphatase/phosphodiesterase-1 (ENPP1) may result in early-onset osteoporosis (EOOP) in haploinsufficiency and autosomal recessive hypophosphatemic rickets (ARHR2) in homozygous deficiency. ARHR2 patients are frequently treated with phosphate supplementation to ameliorate the rachitic phenotype, but elevating plasma phosphorus concentrations in ARHR2 patients may increase the risk of ectopic calcification without increasing bone mass. To assess the risks and efficacy of conventional ARHR2 therapy, we performed comprehensive evaluations of ARHR2 patients at two academic medical centers and compared their skeletal and renal phenotypes with ENPP1-deficient Enpp1asj/asj mice on an acceleration diet containing high phosphate treated with recombinant murine Enpp1-Fc. ARHR2 patients treated with conventional therapy demonstrated improvements in rickets, but all adults and one adolescent analyzed continued to exhibit low bone mineral density (BMD). In addition, conventional therapy was associated with the development of medullary nephrocalcinosis in half of the treated patients. Similar to Enpp1asj/asj mice on normal chow and to patients with mono- and biallelic ENPP1 mutations, 5-week-old Enpp1asj/asj mice on the high-phosphate diet exhibited lower trabecular bone mass, reduced cortical bone mass, and greater bone fragility. Treating the Enpp1asj/asj mice with recombinant Enpp1-Fc protein between weeks 2 and 5 normalized trabecular bone mass, normalized or improved bone biomechanical properties, and prevented the development of nephrocalcinosis and renal failure. The data suggest that conventional ARHR2 therapy does not address low BMD inherent in ENPP1 deficiency, and that ENPP1 enzyme replacement may be effective for correcting low bone mass in ARHR2 patients without increasing the risk of nephrocalcinosis. © 2021 American Society for Bone and Mineral Research (ASBMR). 相似文献
8.
The effectiveness and side effects of Marvelon (0.150 mg desogestrel and 30 mcg ethinyl estradiol) were evaluated in a multicenter study of 1570 women for a total of 22,158 menstrual cycles. Half the women in the study were under age 25. Only 1 pregnancy was reported, and this was due to patient failure. The frequency of spotting and breakthrough bleeding decreased steadily from 22.3% in the 1st treatment cycle, 14.9% in the 2nd, 8.4% in the 6th, 5.6% in the 12th, to 2.8% in the 21st and then rose slightly from 3.6% in the 24th cycle. This pattern of irregular bleeding during the early cycles is common to all oral contraceptive preparations. Changes in body weight were almost negligible and restricted to women under age 20. There was no change in average blood pressure when compared with pretreatment values. Superficial thrombophlebitis occurred in 7 women. Side effects, including nausea, headache, nervousness, depression, and breast tenderness, declined to negligible levels as treatment progressed. Levels of plasma protein sex-hormone-binding globulin (SHBG) appear to be higher with Marvelon than with a similar preparation containing levonorgestrel and ethinyl estradiol. Other studies have noted significantly higher serum high density lipoprotein (HDL) cholesterol levels with Marvelon than with combined levonorgestrel and ethinyl estradiol. This is attributed to the lack of androgenicity of desogestrel in the clinical dosage used in this study. SHBG and serum HDL levels are increased by estrogens and decreased by androgens. 相似文献
9.
S. Weyers G. Selvaggi S. Monstrey M. Dhont R. Van den Broecke P. De Sutter G. De Cuypere G. T‘ Sjoen P. Hoebeke 《Gynecological surgery》2006,3(3):190-194
The objective was to compare the outcome of a combined total hysterectomy-vaginectomy-phalloplasty procedure vs. a vaginectomy-phalloplasty procedure in female-to-male (FTM) gender dysphoric individuals, and to report on a large series of vaginectomies in young women. This was a retrospective study and the setting was the Gender Team at Ghent University Hospital. One hundred and five consecutive cases of vaginectomy-phalloplasty with (one-stage) or without (two-stage) total hysterectomy between 1993 and 2003 were included in the study. Patient files of 69 one-stage and of 36 two-stage procedures were reviewed and analysed. Operation time, the need for transfusions, complications, repeated surgery and hospitalisation time were the main outcome measures. Patients were equally distributed over the study period of 10 years. Comparing the two groups, there was a greater need for transfusion in the group of patients undergoing the one-stage procedure. There was no difference in operation time, rate of major complications or hospitalisation time. One-stage sex reassignment surgery (SRS) in FTM transsexual individuals is associated with more blood loss. However, there is no difference in operative and postoperative complications. Vaginectomy seems to be a safe and relatively simple procedure in FTM transsexual patients. 相似文献
10.
van Aar F Schreuder I van Weert Y Spijker R Götz H Op de Coul E The Partner Notification Group F 《BMC infectious diseases》2012,12(1):114
ABSTRACT: BACKGROUND: Partner notification (PN) among individuals newly diagnosed with HIV/STI is seen as a vital tool to identify others at risk of infection. However, hardly any data are available on the effectiveness of PN on HIV/STI transmission in the Netherlands. This study aims to fill this gap by assessing current PN practices, case-finding effectiveness, and determinants of being notified among men having sex with men (MSM) in the Netherlands. METHODS: Nurses from five STI centers participated in a prospective pilot study on PN outcomes (partners being: at risk, notifiable, notified, and tested) for HIV/STI, by completing a newly developed PN registration form (PN database). PN outcomes including case-finding effectiveness (number of newly diagnosed cases in partners/number of partners being tested) for HIV, syphilis, and gonorrhoea were studied among MSM. Furthermore, the national STI database was analyzed to identify determinants of being notified. The number of infections that remained undetected was estimated based on these two databases. RESULTS: In total 105 MSM, newly diagnosed with HIV/STI, reported 612 sexual partners at risk of whom 41% were notifiable and 31% were notified. Patient referral was the predominant PN method (90%). The overall case-finding percentage was 36% (HIV: 15-33%, gonorrhoea: 17- 50% and syphilis: 4-11%). Case-finding percentages were lower in the national STI database: 21% (5%, 28%, 12%). Persons with one or more sexual partners, known HIV positives, and IDU were more likely to be notified to the STI clinic. Notified clients were more likely to have HIV/STI than unnotified clients (OR 1.7-2.5). Based on these two databases, an estimated 75 to 133 infections remained undetected (HIV: 12-90; gonorrhoea: 28-97; syphilis: 5-12 infections). CONCLUSIONS: Partner notification among MSM in the Netherlands is suboptimal; an extensive number of STI/HIV infections remained undetected mainly due to unnotifiable partners. To enhance PN practices, combined and innovative PN interventions such as Internet-based PN will be implemented for hard-to-reach MSM and other risk groups. 相似文献