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11.
The androgen insensitivity syndrome is a heterogeneous disorder with a wide spectrum of phenotypic abnormalities, ranging from complete female to ambiguous forms that more closely resemble males. The primary abnormality is a defective androgen receptor protein due to a mutation of the androgen receptor gene. This prevents normal androgen action and thus leads to impaired virilisation. A point mutation of the androgen receptor gene affecting two siblings with partial androgen insensitivity syndrome is described. One had cliteromegaly and labial fusion and was raised as a girl, whereas the other sibling had micropenis and penoscrotal hypospadias and was raised as a boy. Both were shown to have the arginine 840 to cysteine mutation. The phenotypic variation in this family is thus dependent on factors other than abnormalities of the androgen receptor gene alone.  相似文献   
12.
Tyrphostin-23 is commonly used as inhibitor of tyrosine kinase (TK). We found that tyrphostin-23 concentration-dependently increased basal steroid-hormone secretion from dispersed human and rat adrenocortical cells, the maximal effective concentration being 10(-5) M. Tyrphostin-23 (10(-5) M) enhanced 10(-9) M angiotensin-II- and endothelin-1-stimulated secretion of human and rat adrenocortical cells, but not the secretory response to 10(-9) M ACTH However, it increased the response to lower concentrations (10(-12) or 10(-11) M) of ACTH. The secretagogue effect of tyrphostin-23 on dispersed rat adrenocortical cells was abolished by either the adenylate cyclase inhibitor SQ-22536 (10(-4) M) or the protein kinase A (PKA) inhibitor H-89 (10(-5) M). Tyrphostin-23 (10(-5) M) raised basal cyclic-AMP release by dispersed rat adrenocortical cells, but in the presence of the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX, 10(-3) M) it was ineffective. Both tyrphostin-23 and IBMX increased cyclic-AMP release by rat adrenocortical cells in response to 10(-10) M ACTH, and their effects were not additive. Taken together, our findings suggest that tyrphostin-23, acting as an inhibitor of phosphodiesterases in adrenocortical cells, increases the intracellular concentration of cyclic-AMP available for PKA activation thereby stimulating steroid-hormone secretion. They also stress that caution must be used in interpreting the results of studies aimed at investigating the possible cross-talk between adenylate cyclase- and TK-dependent signaling cascades.  相似文献   
13.
Australia has a large migrant population with variable fluency in English. Interpreting services help ensure that healthcare services are delivered appropriately to these populations. However, the use of professional interpreters in hospitals is expensive. There are also issues with service availability and convenience. Mobile devices containing software with translating abilities have promising potential to improve communication between patients and hospital staff as an adjunct to professional interpreters. It is highly convenient and inexpensive. There are concerns about the accuracy of the interpretation done with such software and more research needs to be carried out to support or allay these concerns. For now, clinically important and medicolegal related interpretation should be undertaken by professional interpreters whereas less crucial tasks may be performed with the help of interpreting software on mobile devices.  相似文献   
14.
目的:对分级检验在血脂检验中的应用价值进行评价分析,为今后临床检验工作提供可靠的参考依据。方法选取2012年8月~2014年8月在本院接受血脂检验患者109例,均采集血液标本6 ml,平均分成2份,分别采取拉网式检验和分级检验2种不同的检验方法对血脂水平进行检验,对比分析检验结果。结果2种方法在检测低密度脂蛋白胆固醇、载脂蛋白A值和B值方面的结果有显著性差异(P<0.05),三酰甘油、总胆固醇、高密度脂蛋白胆固醇的检验结果则无明显差异(P>0.05)。结论分级检验能够对高血脂进行直接准确检测,临床价值显著,值得关注并推广。  相似文献   
15.
Cardiac masses diagnosis and treatment are a true challenge, although they are infrequently encountered in clinical practice. They encompass a broad set of lesions that include neoplastic (primary and secondary), non-neoplastic masses and pseudomasses. The clinical presentation of cardiac tumors is highly variable and depends on several factors such as size, location, relation with other structures and mobility. The presumptive diagnosis is made based on a preliminary non-invasive diagnostic work-up due to technical difficulties and risks associated with biopsy, which is still the diagnostic gold standard. The findings should always be interpreted in the clinical context to avoid misdiagnosis, particularly in specific conditions (e.g., infective endocarditis or thrombi). The modern multi-modality imaging techniques has a key role not only for the initial assessment and differential diagnosis but also for management and surveillance of the cardiac masses. Cardiovascular magnetic resonance (CMR) allows an optimal non-invasive localization of the lesion, providing multiplanar information on its relation to surrounding structures. Moreover, with the additional feature of tissue characterization, CMR can be highly effective to distinguish pseudomasses from masses, as well as benign from malignant lesions, with further differential diagnosis of the latter. Although histopathological assessment is important to make a definitive diagnosis, CMR plays a key role in the diagnosis of suspected cardiac masses with a great impact on patient management. This literature review aims to provide a comprehensive overview of cardiac masses, from clinical and imaging protocol to pathological findings.  相似文献   
16.
Tsujimoto  T; Lisukov  IA; Huang  N; Mahmoud  MS; Kawano  MM 《Blood》1996,87(8):3375-3383
By using two-color phenotypic analysis with fluorescein isothiocyanate- anti-CD38 and phycoerythrin-anti-CD19 antibodies, we found that pre-B cells (CD38+CD19+) signifcantly decreased depending on the number of plasma cells (CD38++CD19+) in the bone marrow (BM) in the cases with BM plasmacytosis, such as myelomas and even polyclonal gammopathy. To clarify how plasma cells suppress survival of pre-B cells, we examined the effect of plasma cells on the survival of pre-B cells with or without BM-derived stromal cells in vitro. Pre-B cells alone rapidly entered apoptosis, but interleukin-7 (IL-7), a BM stromal cell line (KM- 102), or culture supernatants of KM-102 cells could support pre-B cell survival. On the other hand, inhibitory factors such as transforming growth factor-beta1 (TGF-beta1) and macrophage inflammatory protein- 1beta (MIP-1beta) could suppress survival of pre-B cells even in the presence of IL-7. Plasma cells alone could not suppress survival of pre- B cells in the presence of IL-7, but coculture of plasma cells with KM- 102 cells or primary BM stromal cells induced apoptosis of pre-B cells. Supernatants of coculture with KM-102 and myeloma cell lines (KMS-5) also could suppress survival of pre-B cells. Furthermore, we examined the expression of IL-7, TGF-beta1, and MIP-1beta mRNA in KM-102 cells and primary stromal cells cocultured with myeloma cell lines (KMS-5). In these cells, IL-7 mRNA was downregulated, but the expression of TGF- beta1 and MIP-1beta mRNA was augmented. Therefore, these results suggest that BM-derived stromal cells attached to plasma (myeloma) cells were modulated to secrete lesser levels of supporting factor (IL- 7) and higher levels of inhibitory factors (TGF-beta1 and MIP-1beta) for pre-B cell survival, which could explain why the increased number of plasma (myeloma) cells induced suppression of pre-B cells in the BM. This phenomenon may represent a feedback loop between pre-B cells and plasma cells via BM stromal cells in the BM.  相似文献   
17.
18.
A case report is presented of a rapidly growing congenital nasopharyngeal teratoma (epignathus) in a preterm infant, leading to severe upper airway obstruction. Prenatal diagnosis by ultrasonography did not reveal the condition because the tumour masses were initially small and there was no polyhydramnios. Epignathus is a rare cause of upper airway obstruction of the newborn that can grow rapidly in the neonatal period and should be treated surgically.
Conclusion:  Epignathus is a rare cause of upper airway obstruction of the newborn that can grow rapidly in the neonatal period.  相似文献   
19.
头孢克肟胶囊人体药动学研究及生物等效性评价   总被引:1,自引:0,他引:1  
目的:研究头孢克肟胶囊在健康人体内的药动学及生物等效性。方法:以18名健康志愿者为试验对象,采用同体交叉试验方法,分别单剂量口服受试制剂或参比制剂各400mg,采用HPLC法测定血浆中药物浓度。结果:参比制剂和受试制剂的tmax分别为(3.39±0.50)和(3.39±0.50)h,cmax分别为(2.33±0.33)和(2.27±0.25)μg/mL,t1/2分别为(3.92±0.85)和(4.41±0.68)h,AUC0~16分别为(14.61±2.67)和(14.82±2.02)μg·h·mL^-1,AUC0~∞分别为(16.00±3.13)和(16.81±2.62)μg·h·mL^-1。结论:受试制剂与参比制剂生物等效,受试制剂的相对生物利用度为(98.69±13.13)%。  相似文献   
20.
Atlanto-axial rotatory fixation (AARF) is an uncommon condition which is often missed at presentation because of its rarity and the relative subtlety of plain film X-ray findings, but early detection and appropriate management are vital for a cure. We describe three cases in which the use of spiral computed tomography scanning with 3D and sagittal reconstructions greatly aided diagnosis and management. The 3D images gave a more graphic picture of the overall alignment of the upper cervical spine and the skull base, while the sagittal reconstructions demonstrated the presence or absence of compensatory atlanto-occipital subluxation. The literature is briefly reviewed.  相似文献   
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