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排序方式: 共有818条查询结果,搜索用时 16 毫秒
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G M Christman J F Randolph R P Kelch J C Marshall 《The Journal of clinical endocrinology and metabolism》1991,72(6):1278-1285
Polycystic ovarian disease (PCO) is characterized by hyperandrogenism, ovulatory dysfunction, and altered gonadotropin secretion. Mean plasma FSH concentrations are low, while LH is elevated in a majority of patients. LH pulsatile secretion has been shown to occur at rapid follicular phase frequencies (approximately one pulse per h) in PCO, suggesting persistent rapid frequency GnRH secretion in this disorder. Anovulatory women with PCO were given estradiol (E2; Estraderm skin patches) and progesterone (P; vaginal suppositories) to produce midluteal concentrations for 21 days. The aim was to determine if E2 and P would slow LH (GnRH) pulse frequency and if this would result in augmented FSH secretion and follicular development after withdrawal of E2 and P. Plasma LH was measured every 10 min for 8 h before, during (days 10 and 20), and 7 days after withdrawal of E2 and P (day 28). On each of these study days FSH was measured hourly, and E2 and P were measured every 2 h. After sampling, GnRH (25 and 250 ng/kg, iv) was given to assess pituitary responsiveness. Follicular development was monitored by vaginal ultrasound through day 34 of the study. Basal LH frequency was 8.5 +/- 0.5 pulses/8 h (mean +/- SEM). During E2 and P, LH pulse frequency fell to 3.3 +/- 1.0 (10 days) and 2.3 +/- 0.8 (20 days), 39% and 27% of the basal value, respectively, and subsequently increased to 5.6 +/- 0.7 (66% of basal) 7 days after withdrawal of E2 and P. LH pulse amplitude (basal, 7.2 +/- 1.5 IU/L) was not reduced until day 20, but remained suppressed (3.9 +/- 1.1 IU/L) on day 28. As a result, mean LH (basal, 21.0 +/- 3.5 IU/L) fell progressively during E2 and P, to 3.8 +/- 1.2 IU/L on day 20, and remained low (39% of basal) 7 days after steroid withdrawal. Mean plasma FSH (basal, 7.1 +/- 0.9 IU/L) also fell during steroid administration, but in contrast to LH, had risen to 93% of the basal value by 7 days after E2 and P. LH release in response to exogenous GnRH revealed marked initial responses which did not decrease until day 20, but remained suppressed (8% of basal) after withdrawal of E2 and P. FSH responses were also suppressed on day 20, but had increased to 75% of the basal value by day 28. Initiation of follicular development occurred in all patients, and the lead follicle measured 12.3 +/- 0.8 mm 13 days post-E2 and P. Ovulation occurred in one patient.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
4.
L Christman 《American journal of psychotherapy》1987,41(3):384-390
Up to now not many patients have interacted with trained psychiatric nurses, since their numbers have been small. It is only a recent development that nurses are continuing their education to the Master's and Ph.D. levels. Suggestions for courses are made. Because of the growing convergence of the biological and behavioral sciences, nurses will be in a strong position to provide effective patient management. Their traditional involvement in the community, the work place, the schools, as well as the fact that they are in close contact with medical and surgical patients in particular stressful situations, may enable them not only to treat but even mitigate emergent psychopathology. Nurses would be uniquely placed to interact with other members of the mental health professions and to supplement their work. 相似文献
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Sepsis and cytokines: current status 总被引:26,自引:0,他引:26
Sepsis is a constellation of clinical signs and symptoms resulting from
excessive systemic host inflammatory response to infection. This
inflammatory response is largely mediated by cytokines, which are released
into the systemic circulation. Plasma concentrations of specific cytokines,
TNF alpha, IL-1 beta, IL-6 and IL-8 are frequently elevated in human sepsis
and cytokine concentrations correlate with severity and outcome of sepsis.
In addition to pro-inflammatory cytokines, soluble cytokine receptors,
cytokine receptor antagonists and counter-inflammatory cytokines are also
produced in large quantities in patients with sepsis; however, the specific
role of these molecules in sepsis remains undefined. A complex interaction
of cytokines and cytokine-neutralizing molecules probably determines the
clinical presentation and course of sepsis. Intervening in this sequence of
events to modify the host inflammatory responses may prove to be a
beneficial treatment strategy for sepsis, but currently tested anticytokine
therapies have been largely unsuccessful.
相似文献
7.
Evaluation of three substitutes for Percoll in sperm isolation by density gradient centrifugation 总被引:9,自引:4,他引:9
Silane-coated silica particle solutions (ISolate(TM) and PureSperm)TM)) and
iodixanol (OptiPrep(TM)) were compared to polyvinylpyrrolidone (PVP)-coated
silica particles (Percoll(TM)) in their efficacy to recover spermatozoa by
gradient centrifugation for use in assisted reproductive procedures.
Efficacy was assessed in terms of percentages of sperm recovery, sperm
vitality and motility, normal sperm morphology and normal sperm chromatin
condensation. No significant difference was found in the recovery of
spermatozoa for men with both normal sperm counts and oligozoospermia,
between PVP-coated and silane-coated particle solutions. Iodixanol had
significantly lower sperm recovery compared to the other products. Sperm
vitality, progressive motility, normal morphology and normal chromatin
condensation did not differ significantly between any of the sperm
isolation products.
相似文献
8.
Intratracheal administration of liposomal clodronate accelerates alveolar macrophage reconstitution following fetal liver transplantation 总被引:1,自引:0,他引:1
Everhart MB Han W Parman KS Polosukhin VV Zeng H Sadikot RT Li B Yull FE Christman JW Blackwell TS 《Journal of leukocyte biology》2005,77(2):173-180
To facilitate study of alveolar macrophages in vivo, we developed a method to rapidly and efficiently replace resident alveolar macrophages with macrophages of a different (donor) genotype. Chimeric mice were generated by lethal irradiation followed by fetal liver transplantation (FLT) using green fluorescent protein (GFP) transgenic reporter mice as donors. Kinetics of peripheral blood monocyte (PBM) and alveolar macrophage reconstitution was determined 4 and 10 weeks post-FLT by quantifying the percentage of GFP+ cells. To enhance the recruitment of donor monocytes into the lung after FLT, mice were treated with intratracheal administration of liposomal clodronate to deplete host alveolar macrophages at 6 weeks post-FLT. PBM reconstitution occurred by 4 weeks after FLT (85.7+/-1.6% of CD11b+/Gr-1+ monocytes were GFP+), and minimal alveolar macrophage repopulation was observed (9.5% GFP+). By 10 weeks following FLT, 48% of alveolar macrophages were GFP+ by immunostaining of macrophages on lung tissue sections, and 55.1 +/- 1.6% of lung lavage macrophages were GFP+ by fluorescein-activated cell sorter analysis. Clodronate treatment resulted in a significant increase in GFP+ alveolar macrophages 10 weeks after FLT. By immunostaining, 90% of macrophages were GFP+ on lung tissue sections and 87.5 +/- 1.1% GFP+ in lung lavage (compared with GFP-transgenic controls). The ability of newly recruited alveolar macrophages to clear Pseudomonas aeruginosa and activate nuclear factor-kappaB in response to Eschericia coli lipopolysaccharide demonstrated normal macrophage function. Optimizing this methodology provides an important tool for the study of specific genes and their contribution to alveolar macrophage function in vivo. 相似文献
9.
Mutation spectrum and genotype-phenotype analyses in Cowden disease and Bannayan-Zonana syndrome, two hamartoma syndromes with germline PTEN mutation 总被引:22,自引:1,他引:22
Marsh DJ; Coulon V; Lunetta KL; Rocca-Serra P; Dahia PL; Zheng Z; Liaw D; Caron S; Duboue B; Lin AY; Richardson AL; Bonnetblanc JM; Bressieux JM; Cabarrot-Moreau A; Chompret A; Demange L; Eeles RA; Yahanda AM; Fearon ER; Fricker JP; Gorlin RJ; Hodgson SV; Huson S; Lacombe D; Eng C 《Human molecular genetics》1998,7(3):507-515
The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403
amino acid dual specificity phosphatase (protein tyrosine phosphatase;
PTPase), was shown recently to play a broad role in human malignancy.
Somatic PTEN deletions and mutations were observed in sporadic breast,
brain, prostate and kidney cancer cell lines and in several primary tumours
such as endometrial carcinomas, malignant melanoma and thyroid tumours. In
addition, PTEN was identified as the susceptibility gene for two hamartoma
syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or
Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD
families and seven BZS families was screened for germline PTEN mutations.
PTEN mutations were identified in 30 of 37 (81%) CD families, including
missense and nonsense point mutations, deletions, insertions, a
deletion/insertion and splice site mutations. These mutations were
scattered over the entire length of PTEN , with the exception of the first,
fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified
in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD
mutations identified in this exon. Seven of 30 (23%) were within the core
motif, the majority (five of seven) of which were missense mutations,
possibly pointing to the functional significance of this region. Germline
PTEN mutations were identified in four of seven (57%) BZS families studied.
Interestingly, none of these mutations was observed in the PTPase core
motif. It is also worthy of note that a single nonsense point mutation,
R233X, was observed in the germline DNA from two unrelated CD families and
one BZS family. Genotype-phenotype studies were not performed on this small
group of BZS families. However, genotype-phenotype analysis inthe group of
CD families revealed two possible associations worthy of follow-up in
independent analyses. The first was an association noted in the group of CD
families with breast disease. A correlation was observed between the
presence/absence of a PTEN mutation and the type of breast involvement
(unaffected versus benign versus malignant). Specifically and more
directly, an association was also observed between the presence of a PTEN
mutation and malignant breast disease. Secondly, there appeared to be an
interdependent association between mutations upstream and within the PTPase
core motif, the core motif containing the majority of missense mutations,
and the involvement of all major organ systems (central nervous system,
thyroid, breast, skin and gastrointestinal tract). However, these
observations would need to be confirmed by studying a larger number of CD
families.
相似文献
10.
Venkatakrishnan A Stecenko AA King G Blackwell TR Brigham KL Christman JW Blackwell TS 《American journal of respiratory cell and molecular biology》2000,23(3):396-403
In cystic fibrosis (CF), inflammatory mediator production by airway epithelial cells is a critical determinant of chronic airway inflammation. To determine whether altered signal transduction through the nuclear factor (NF)-kappaB pathway occurs in CF epithelial cells and results in excessive generation of inflammatory cytokines, we evaluated tumor necrosis factor (TNF)-alpha-induced production of the NF-kappaB-dependent cytokine interleukin (IL)-8 and activation of NF-kappaB in three different human bronchial epithelial cell lines: (1) BEAS cells that express wild-type CF transmembrane conductance regulator (CFTR), (2) IB3 cells with mutant CFTR, and (3) C38 cells, which are "corrected" IB3 cells complemented with wild-type CFTR. Treatment of cells with TNF-alpha (30 ng/ml) resulted in markedly elevated NF-kappaB activation and production of IL-8 by IB3 cells compared with BEAS and C38 cells. Despite the differences in NF- kappaB activation, no differences in basal levels of IkappaB-alpha or TNF-alpha- induced IkappaB-alpha processing and degradation were detected among the cell lines. In contrast, the basal level of IkappaB-beta was increased in the IB3 cells. Treatment with TNF-alpha resulted in increased formation of hypophosphorylated IkappaB-beta and increased nuclear localization of IkappaB-beta in IB3 cells compared with the other cell types. These findings provide additional evidence of a dysregulated inflammatory response in CF. 相似文献