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41.
42.
磷酸二酯酶5(PDE5)影响环磷酸鸟苷(cGMP)维持血管平滑肌紧张性的生理学效应,在阴茎海绵体的静脉系统和肺血管系统中尤为明显。 相似文献
43.
G Zaidi RP Sahu L Zhang G George N Bhavani N Shah V Bhatia A Bhansali G Jevalikar RV Jayakumar GS Eisenbarth E Bhatia 《Clinical genetics》2009,76(5):441-448
Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a rare recessive disorder resulting from mutations in the autoimmune regulator ( AIRE ) gene. There is no information on AIRE mutations in Indians. In a cross-sectional study, nine patients (eight families), from four referral hospitals in India, were studied for AIRE mutations by direct sequencing. We screened for new mutations in 150 controls by allele-specific PCR. The patients had 1–7 known components of APECED. Three patients had unusual manifestations: presentation with type 1 diabetes; chronic sinusitis and otitis media; and facial dysmorphism. All patients carried homozygous, probably recessive, AIRE mutations. Two unrelated patients from a small in-bred community (Vanika Vaisya) in south India carried an unreported missense mutation, p.V80G, in the N-terminal caspase recruitment domain. Another unique mutation, p.C302X, resulting in a truncated protein with deletion of both zinc-finger domains, was detected in a patient from Gujarat. Neither mutation was detected in controls. Other mutations, previously described in Caucasians, were: 13 base pair deletion (p.C322fsX372) in 4 (38%), and Finn-major (p.R257X) and p.R139X (Sardinian) mutation in one subject each. In conclusion, in this first series of APECED in Indians, we detected AIRE mutations previously reported in Caucasians, as well as unique mutations. Of these, p.V80G is possibly an ancestral mutation in an in-bred community. 相似文献
44.
Association of the steroid synthesis gene CYP11a with polycystic ovary syndrome and hyperandrogenism 总被引:12,自引:0,他引:12
Gharani N; Waterworth DM; Batty S; White D; Gilling-Smith C; Conway GS; McCarthy M; Franks S; Williamson R 《Human molecular genetics》1997,6(3):397-402
Biochemical data implicate an underlying disorder of androgen biosynthesis
and/or metabolism in the aetiology of polycystic ovary syndrome (PCOS). We
have examined the segregation of the genes coding for two key enzymes in
the synthesis and metabolism of androgens, cholesterol side chain cleavage
(CYP11a) and aromatase (CYP19), with PCOS in 20 multiply-affected families.
All analyses excluded CYP19 cosegregation with PCOS, demonstrating that
this locus is not a major determinant of risk for the syndrome. However,
our results provide evidence for linkage to the CYP11a locus (NPL score =
3.03, p = 0.003). Parametric analysis using a dominant model suggests
genetic heterogeneity, generating a maximum HLOD score of 2.7 (alpha =
0.63). An association study of 97 consecutively identified Europids with
PCOS and matched controls demonstrates significant allelic association of a
CYP11a 5' UTR pentanucleotide repeat polymorphism with hirsute PCOS
subjects (p = 0.03). A strong association was also found between alleles of
this polymorphism and total serum testosterone levels in both affected and
unaffected individuals (p = 0.002). Our data demonstrate that variation in
CYP11a may play an important role in the aetiology of hyperandrogenaemia
which is a common characteristic of polycystic ovary syndrome.
相似文献
45.
46.
D Arora TK Bhattacharyya SK Kathpalia SPS Kochar GS Sandhu VSM BK Goyal 《Medical Journal Armed Forces India》2007,63(1):7-11
Background
The aim of this study was to assess the role of middle cerebral artery peak systolic velocity (MCA-PSV), as measured by doppler ultrasound, in detecting foetal anaemia in Rh- isoimmunised pregnancies. Intra-uterine foetal blood transfusion was performed in such anaemic foetuses to tide over the crisis of foetal immaturity till considered fit for extra-uterine survival.Methods
Rh-isoimmunised pregnancies reporting to a tertiary institute from 2003 to 2005, were screened by doppler ultrasound to estimate MCA-PSV to detect foetal anaemia. If the foetus developed MCA-PSV of more than 1.5 multiple of median (MoM) for the gestational age, foetal blood sampling through cordocentesis was performed to confirm foetal anaemia, followed by intrauterine foetal blood transfusion to all anaemic foetuses at the same sitting. Neonatal outcome was evaluated by recording gestational age at the time of delivery, duration of gestational time gained and need for blood transfusion in the neonatal period.Results
A total of thirteen isoimmunised pregnancies were evaluated. Three pregnancies did not require in-utero foetal blood transfusion. Twenty-one intrauterine foetal blood transfusions were performed in the remaining ten patients. Five received blood transfusion in the neonatal period. Intra uterine foetal death occurred in one grossly hydropic foetus and favourable neonatal outcome was recorded in the rest.Conclusion
The clinical outcome of these pregnancies justifies the use of doppler studies of MCA-PSV in detecting foetal anaemia and intra uterine foetal blood transfusion is the only hope of prolonging pregnancy and salvaging such foetuses.Key Words: Rh-isoimmunisation, Middle cerebral artery peak systolic velocity, Foetal anaemia, Foetal blood transfusion 相似文献47.
Follicle lysis is a characteristic alteration of B cell follicles described recently in lymph node biopsies from homosexual men. It consists of disruption of germinal centers by aggregates of small mature lymphocytes variably associated with erythrocyte extravasation. We studied the immunohistology of follicle lysis identified in lymph node biopsies from 11 homosexual men. The results indicate that follicle lysis has two principal immunohistologic features: (1) intrafollicular aggregates of small lymphocytes predominantly of polytypic mantle B cell phenotype (T015+/Leu-8+/mu+/delta+/k+ or lambda+), and (2) disruption of the normal, unified follicular meshwork of R4/23+ dendritic reticulum cells by these B cell aggregates. These structural alterations may affect the functional integrity of the germinal center as it pertains to the abnormal B cell effector function and the increased prevalence of B cell lymphoma recently documented in the acquired immunodeficiency syndrome and related disorders. Because dendritic reticulum cells weakly express the Leu-3 (T4) antigen, which is known to be an essential component of the receptor for human T- lymphotropic virus type III/lymphadenopathy-associated virus (HTLV- III/LAV) retrovirus infection, it is possible that retroviral infection of dendritic reticulum cells may play a role in the pathogenesis of follicle lysis. 相似文献
48.
49.
Factors associated with nursing assistant quality-of-life ratings for residents with dementia in long-term care facilities 总被引:1,自引:0,他引:1
PURPOSE: We identify resident, nursing assistant, and facility factors associated with nursing assistant quality-of-life ratings for residents with dementia in long-term care. DESIGN AND METHODS: We used a cross-sectional survey of 143 nursing assistants providing care to 335 residents in 38 residential care/assisted living (RC/AL) facilities and nursing homes in four states. We assessed resident quality of life by using the Quality of Life-Alzheimer's Disease Scale (QOL-AD). RESULTS: Scores on the quality-of-life scale were most strongly associated with resident clinical conditions, including severity of cognitive and functional impairments, depression, and behavioral symptoms of dementia. There was also an independent positive association between nursing assistants' ratings of resident quality of life and their own attitudes regarding dementia-person-centered care as well as training. However, the results of hierarchical linear modeling suggest that some sources of nursing assistant variability in quality-of-life ratings remain unidentified. IMPLICATIONS: Quality-of-life ratings by nursing assistants may be influenced by their attitudes about dementia and their confidence in addressing residents' fundamental care needs. 相似文献
50.
Role of p21 RAS in p210 bcr-abl transformation of murine myeloid cells 总被引:11,自引:2,他引:11
Mandanas RA; Leibowitz DS; Gharehbaghi K; Tauchi T; Burgess GS; Miyazawa K; Jayaram HN; Boswell HS 《Blood》1993,82(6):1838-1847
The p21 RAS product has been implicated as part of the downstream signaling of certain nonreceptor tyrosine kinase oncogenes and several growth factor receptor-ligand interactions. We have reported that the chronic myelogenous leukemia oncogene p210 bcr-abl transforms a growth- factor-dependent myeloid cell line NFS/N1.H7 to interleukin-3 (IL-3) independence. In these p210 bcr-abl-transformed cells (H7 bcr-abl.A54) and in two other murine myeloid cell lines transformed to IL-3 independence by p210 bcr-abl, endogenous p21 RAS is activated as determined by an elevated ratio of associated guanosine triphosphate (GTP)/guanosine diphosphate (GDP), assayed by thin-layer chromatography of the nucleotides eluted from p21 RAS after immunoprecipitation with the Y13-259 antibody. Treatment of p210 bcr-abl-transformed cells with a specific tyrosine kinase inhibitor herbimycin A resulted in diminished tyrosine phosphorylation of p210 bcr-abl and associated proteins, without major reduction in expression of the p210 bcr-abl protein itself. Inhibition of p210 bcr-abl-dependent tyrosine phosphorylation resulted in a reduction of active p21RAS-GTP complexes in the transformed cells, in diminished expression of the nuclear early response genes c-jun and c-fos, and in lower cellular proliferation rate. To further implicate p21 RAS in these functional events downstream of p210 bcr-abl tyrosine phosphorylation, we targeted G- protein function directly by limiting the availability of GTP with the inosine monophosphate dehydrogenase inhibitor, tiazofurin (TR). In p210 bcr-abl-transformed cells treated for 4 hours with TR, in which the levels of GTP were reduced by 50%, but GDP, guanosine monophosphate, and adenosine triphosphate (ATP) were unaffected, p210 bcr-abl tyrosine phosphorylation was at control levels. However, expression of c-fos and c-jun nuclear proto-oncogenes were strongly inhibited and p21 RAS activity was downregulated. These findings show that p210 bcr-abl transduces proliferative signals, in part, through downstream activation of p21 RAS. Furthermore, p21 RAS activity is linked to pathways that regulate c-jun and c-fos expression. 相似文献