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81.
82.
This paper describes the tragic case of a young woman who died of cancer of
the colon after successfully donating eggs to her younger sister. Although
there is no direct link between her operation and the subsequent
development of bowel carcinoma, this case imparts a feeling of unease when
seen in conjunction with other cases reported during the last few years. It
is a reminder that little is known of the long-term consequences of some
aspects of assisted conception. Women undergoing ovarian stimulation for
themselves or a matched recipient have the right to be advised, in an
agreed format, that there is some concern about unproven potential risks
from the stimulatory drugs. The safety of egg donors must assume priority
over all other considerations, including lack of donors or any moral
position. The recent decision by the Human Fertilisation and Embryology
Authority (HFEA) to withdraw any form of payment or recompense to egg
donors does not seem to us to be based on a balance of scientific advances,
patient needs and the ethics of gamete supply. They state that the
intention to withdraw payments was implicit in the 1990 Human Fertilisation
and Embryology (HFE) Act. However the Act was based on the Warnock report
made 6 years earlier. Even in 1990 ovum donation was uncommon and fertility
drugs had not yet caused any unease. The Act provided the HFEA with
discretionary powers to issue directions so that the future policies would
be consistent with any emerging new medical evidence. It is imperative that
the HFEA provide convincing evidence on how the current policy of payment
to donors harms society, donors or recipients, and how in the UK the new
policy will improve medical practice in assisted conception. Successful
pilot studies must precede the implementation of any new policy. Failure to
do this could cause irreversible harm to the practice of assisted
conception using donor gametes, which will ultimately be against the basic
aims of the 1990 HFE Act.
相似文献
83.
Pseudoangiomatous stromal hyperplasia (PASH) is an uncommon lesion usually found in premenopausal women. Histologically, it is characterized by complex, anatomosing, empty slit-like spaces in a dense collagenous stroma. These pseudoangiomatous spaces are lined by monomorphic spindle cells of myofibroblastic differentiation. Cytological features of PASH are rarely discussed and reported, and may pose diagnostic challenge to surgical pathologists. Two cases of PASH are reported with emphasis on the FNAC features and cytologic differentiation from other benign fibroepithelial lesions. 相似文献
84.
85.
Mutations in the Ca(2+)-sensing receptor gene cause autosomal dominant and sporadic hypoparathyroidism 总被引:3,自引:0,他引:3
Baron J; Winer KK; Yanovski JA; Cunningham AW; Laue L; Zimmerman D; Cutler GB Jr 《Human molecular genetics》1996,5(5):601-606
Parathyroid hormone secretion is negatively regulated by a 7- transmembrane
domain, G-protein coupled Ca(2+)-sensing receptor. We hypothesized that
activating mutations in this receptor might cause autosomal dominant
hypoparathyroidism (ADHP). Consistent with this hypothesis, we identified,
in two families with ADHP, heterozygous missense mutations in the
Ca(2+)-sensing receptor gene that cosegregated with the disorder. None of
50 normal controls had either mutation. We also identified a de novo,
missense Ca(2+)-sensing receptor mutation in a child with severe sporadic
hypoparathyroidism. The amino acid substitution in one ADHP family affected
the N-terminal, extracellular domain of the receptor. The other mutations
involved the transmembrane region. Unlike patients with acquired
hypoparathyroidism, patients with these mutations had hypercalciuria even
at low serum calcium concentrations. Their greater hypercalciuria
presumably reflected activation of Ca(2+)-sensing receptors in kidney
cells, where the receptor negatively regulates calcium reabsorption. This
augmented hypercalciuria increases the risk of renal complications and thus
has implications for the choice of therapy.
相似文献
86.
K.K.W. To C.C.Y. Yip C.Y.W. Lai C.K.H. Wong D.T.Y. Ho P.K.P. Pang A.C.K. Ng K.-H. Leung R.W.S. Poon K.-H. Chan V.C.C. Cheng I.F.N. Hung K.-Y. Yuen 《Clinical microbiology and infection》2019,25(3):372-378
Objectives
Automated point-of-care molecular assays have greatly shortened the turnaround time of respiratory virus testing. One of the major bottlenecks now lies at the specimen collection step, especially in a busy clinical setting. Saliva is a convenient specimen type that can be provided easily by adult patients. This study assessed the diagnostic validity, specimen collection time and cost associated with the use of saliva.Methods
This was a prospective diagnostic validity study comparing the detection rate of respiratory viruses between saliva and nasopharyngeal aspirate (NPA) among adult hospitalized patients using Xpert® Xpress Flu/RSV. The cost and time associated with the collection of saliva and nasopharyngeal specimens were also estimated.Results
Between July and October 2017, 214 patients were recruited. The overall agreement between saliva and NPA was 93.3% (196/210, κ 0.851, 95% CI 0.776–0.926). There was no significant difference in the detection rate of respiratory viruses between saliva and NPA (32.9% (69/210) versus 35.7% (75/210); p 0.146). The overall sensitivity and specificity were 90.8% (81.9%–96.2%) and 100% (97.3%–100%), respectively, for saliva, and were 96.1% (88.9%–99.2%) and 98.5% (94.7%–99.8%), respectively, for NPA. The time and cost associated with the collection of saliva were 2.26-fold and 2.59-fold lower, respectively, than those of NPA.Conclusions
Saliva specimens have high sensitivity and specificity in the detection of respiratory viruses by an automated multiplex Clinical Laboratory Improvement Amendments-waived point-of-care molecular assay when compared with those of NPA. The use of saliva also reduces the time and cost associated with specimen collection. 相似文献87.
Kobayashi Y Pang T Iwamoto T Wakabayashi S Shigekawa M 《Pflügers Archiv : European journal of physiology》2000,439(4):455-462
Replacement of external NaCl with LiCl induced cytoplasmic alkalinization in CCL-39 cells and rat L6 myoblasts expressing the endogenous Na+/H+ exchanger isoform NHE1. This Li+-induced alkalinization is due to activation of the Na+/H+ exchanger because it was completely inhibited by 100 microM ethylisopropylamiloride (apparent Kd=1 microM) and because it did not occur in exchanger-deficient PS120 cells. The effect of Li+ was not mimicked by Na+, K+, Cs+ and choline+. Li+ caused cytoplasmic alkalinization in PS120 cells expressing NHE1 or NHE2, but not NHE3, when Li+ was added to cells at a concentration high enough to saturate their external transport sites as predicted from Li+ affinities. Li+ did not induce phosphatidylinositol (PI) turnover or intracellular Ca2+ mobilization. Li+-induced alkalinization was not affected by protein kinase C down-regulation, loss of glycogen synthase kinase 3beta caused by antisense oligonucleotide treatment, or pretreatment with calphostin C, pertussis toxin, MEK inhibitor PD98059 and PI3-kinase inhibitor LY294002. However, it was markedly suppressed by the tyrosine kinase inhibitor genistein (10 microM). Thus, externally added Li+ activates NHE1 and NHE2 via a mechanism possibly involving a tyrosine kinase, causing an increase in cytoplasmic pH that could potentially affect various cell functions. 相似文献
88.
Wong N Hui AB Fan B Lo KW Pang E Leung SF Huang DP Johnson PJ 《Cancer Genetics and Cytogenetics》2003,140(2):124-132
Nasopharyngeal carcinoma (NPC) cell lines and xenografts represent valuable models for functional and therapeutic studies on this common malignancy in Southeast Asia. The karyotypic information in most NPC cell lines and xenografts, however, remains largely unclear to date. We have characterized the chromosomal aberrations in six commonly used human NPC cell lines and xenografts using the molecular cytogenetic technique of comparative genomic hybridization (CGH). Genomic imbalances identified in cell lines were further correlated with structural abnormalities indicated from spectral karyotyping (SKY) analysis. CGH revealed consistent overrepresentations of 8q (six out of six cases) with a smallest overlapping region identified on 8q21.1q22. Other common gains included 7p (4/6 cases), 7q (4/6 cases), 12q (4/6), and 20q (4/6 cases), where minimal overlapping regions were suggested on 7p15p14, 7q11.2q21, and 12q22q24.1. Common losses were detected on 3p12p21 (4/6 cases) and 11q14qter (4/6 cases). Although SKY analysis on cell lines revealed predominantly unbalanced rearrangements, reciprocal translocations that involved chromosome 2 [i.e., t(1;2), t(2;3), and t(2;4)] were suggested. Furthermore, SKY examination illustrated additional breakpoints on a number of apparently balanced chromosomes. These breakpoints included 3p21, 3q26, 5q31, 6p21.1p25, 7p14p22, and 8q22. Our finding of regional gains and losses and breakpoints represents information that may contribute to NPC studies in vitro. 相似文献
89.
新疆南疆地区嗜人T淋巴细胞病毒I型血清流行病学调查 总被引:8,自引:1,他引:8
通过血清流行病学调查,了解人嗜T淋巴细胞病毒I型(HTLV-1)在新疆南部(南疆)少数民族地区的流行情况,自南疆喀什,和田,阿图什地区采集正常人群中不同年龄组,不同民族的血清标本2642份,其中维吾尔族(维族)1082份,汉族1089份,柯尔克孜族(柯族)471份。用免疫荧光法(IFA)检测上述血清中HTLV-1IgG抗体,结果维族抗体阳性者为0.74%(8/1082)汉族为0(0/1089)柯族 相似文献
90.
应用制霉菌素穿孔全细胞电压钳技术.在急性分离的大鼠骶髓后连合核(SDCN)神经元上,研究抑制性氨基酸诱导的反应的电生理学和药理学特性。当钳制电压为-40mV时,γ-氨基丁酸(GABA)、甘氨酸(Gly)和牛磺酸(Tau)均诱导产生内向电流。它们的EC50值分别是GABA5.2×10-5M,Gly4.0×10-5M及Tau1.6×10-4M。其Hill系数分别为GABA1.21,Gly1.27和Tau1.23。所有这些电流均在膜电位为-1.8mV左右时翻转。此外.Tau和Gly反应问还存在很强的交叉脱敏。结果提示,GABAA,Gly和Tau作为递质,通过受体Cl-通道复合体.在调节SDCN社经元伤害性传递中可能有重要作用。 相似文献