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31.
Most Ig receptors exist as hetero-oligomeric complexes with separate ligand binding (alpha) and signal transducing (beta, gamma, or zeta) subunits. For Fc gamma RIIIa and Fc epsilon RI, association with the FcR gamma-chain is essential for surface expression. However, the human high affinity IgG receptor, hFc gamma RI, was found to be surface- expressed by itself in transient transfection models. We have now analyzed the integrity of hFc gamma RI expression in more detail in stable transfectants. In vitro we noted that, in the absence of FcR gamma-chain, surface expression of hFc gamma RI rapidly declined to background levels, in both IIA1.6 B cells and NIH3T3 fibroblasts. The effect of FcR gamma-chain on hFc gamma RI surface expression in vivo was evaluated by using two newly generated transgenic mouse lines, selectively expressing hFc gamma RI on myeloid cells. These transgenic mice were crossed with FcR gamma-chain-deficient mice. Analysis of blood monocytes and peritoneal macrophages showed that surface expression of hFc gamma RI was reduced by approximately 80%. The remaining approximately 20% of receptors were still capable of binding IgG-opsonized RBC, suggesting FcR gamma-chain not to be critical for hFc gamma RI ligand-binding capacity. Importantly, however, hFc gamma RI signaling capacity was lost in FcR gamma-chain-deficient cells. No phagocytosis could be observed using either ligand sensitized (EA- IgG2a) or CD64-targeted erythrocytes (using a bispecific antibody) in both hFc gamma RI transgenic lines. This documents the FcR gamma-chain to be indispensable for both surface membrane expression and function of human Fc gamma RI in vivo.  相似文献   
32.
Autosomal recessive nonsyndromic hearing impairment (ARNSHI) segregating in three unrelated, large consanguineous Pakistani families (PKDF528, PKDF859 and PKDF326) is linked to markers on chromosome 12q14.2-q15. This novel locus is designated DFNB74 . Maximum two-point limit of detection (LOD) scores of 5.6, 5.7 and 2.6 were estimated for markers D 12 S 313, D 12 S 83 and D 12 S 75 at θ = 0 for recessive deafness segregating in these three families. Haplotype analyses identified a critical linkage interval of 5.35 cM (5.36 Mb) defined by D 12 S 329 at 74.58 cM and D 12 S 313 at 79.93 cM. DFNB74 is the second ARNSHI locus mapped to chromosome 12, but the physical intervals do not overlap with one another. A locus contributing to the early onset, rapidly progressing hearing loss of A/J mice ( ahl4 , age-related hearing loss 4) was reported to map to chromosome 10 in a region of conserved synteny to DFNB74 , suggesting that ahl4 and DFNB74 may be due to mutations of the same gene in these two species.  相似文献   
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34.

Background  

Influenza surveillance systems provide important and timely information to health service providers on trends in the circulation of influenza virus and other upper respiratory tract infections. Online dissemination of surveillance data is useful for risk communication to health care professionals, the media and the general public. We reviewed national influenza surveillance websites from around the world to describe the main features of surveillance data dissemination.  相似文献   
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建立了人血清中双氯芬酸的反相高效液相色谱测定方法。该法操作简便、精密度好、方法回收率为98.2~102.5%,日内、日间RSD为1.29~4。52%,血药浓度在0.2~10μg/ml范围内呈线性关系,相关系数0;9999,当信噪比为2时,最低检测限为10ng/ml。健康志愿者口服100mg双氯芬酸肠溶衣片,药代动力学过程符合一室开放模型,消除半衰期为2.15h。  相似文献   
37.
Background: Calcitonin gene-related peptide (CGRP) is known to have an extremely potent and prolonged vasodilator effect on the coronary arteries. Studies have shown that CGRP increased coronary blood flow and alleviated reperfusion injury in vitro. It is still unknown, however, whether exogenous CGRP has a protective effect on the reperfusion heart associated with cardiopulmonary bypass (CPB). Methods: An in vivo porcine model of CPB was established. Twenty pigs, 10 controls and 10 CGRP used animals (CGRP group), were performed a median sternotomy followed by a standard CPB. All the hearts were arrested for 45 minutes. In the CGRP group, 1mg/kg CGRP was added into the cardioplegia, and another 1mg/kg was reperfused just before the aortic cross-clamp was removed. In both groups, myocardial microvascular perfusion, coronary arterial microvessel diameter and microvessel blood flow were detected by a laser doppler flowmeter and a contact microscope with TV monitor on five consecutive time perioperatively. Result: Myocardial microvascular perfusion was significantly higher and coronary arterial microvessel diameter was larger in the CGRP group on every point of time of reperfusion compared to those in the control group. In the CGRP group, microvessel blood flow also improved significantly than that in the control group during reperfusion. Conclusion: CGRP improves myocardial microcirculation during cardiac ischemia-reperfusion associated with CPB and could become a new, potent myocardial protector.  相似文献   
38.
BACKGROUND: To present preparedness planning for an influenza pandemic for two nursing subunits: nursing services in hospitals and schools of nursing in universities. DISCUSSION: The preparedness plan is modeled on a modified Haddon matrix, a logical approach to identify measures appropriate for the pre-event, event, and postevent phases of an influenza pandemic. For the pre-event phase, the objective is to ensure preparedness for the potential pandemic outbreak through training, communication, surveillance, infection control, and vaccination. Once the pandemic outbreak is declared, the aim is to implement effective measures to ensure a rapid and appropriate response. For the postevent phase, the plan is focused on the restoration of core functions, vigilance for a second or possibly more waves of the pandemic, and psychosocial support to staff and students. CONCLUSION: Measures required to prepare for, respond to, and manage the consequences of influenza pandemic are identified. This planning indicates the need to balance a logical approach with contextual perspectives and the importance for nursing leaders to develop plans for subunits of larger entities.  相似文献   
39.

BACKGROUND:

Psychosocial stress can be the cause or the consequence of hypertension.

OBJECTIVE:

To study the association between hypertension and anxiety or depression in adults from Hong Kong, China.

SUBJECTS AND METHODS:

Patients with diagnosed hypertension (n=197) were recruited to complete the Hospital Anxiety and Depression Scale (HADS) questionnaire. The control group comprised 182 normotensive subjects recruited using random telephone numbers.

RESULTS:

The score in the anxiety subscale (HADS-A) of the HADS correlated with age (r= −0.23, P<0.001) and sex (r=0.11, P=0.042), and was found to be higher in women. The score in the depression subscale (HADS-D) correlated with age (r=0.17, P=0.003) and hypertension (r=0.12, P=0.039), but not with sex (r=0.02, P=0.68). When the control subjects were matched for sex and age with the subjects with hypertension, the mean HADS-A score was 5.51±0.41 in 113 hypertensive subjects and 4.38±0.39 in 113 normotensive subjects (P=0.047). The mean HADS-D score was 5.56±0.39 in the hypertensive and 4.76±0.32 in the normotensive subjects (P=0.11). Multiple regression analysis using data from both groups indicated that the HADS-A score was related to the HADS-D score (β=0.49, P<0.001), age (β= −0.25, P<0.001) and sex (β=0.12, P=0.01) (R2=0.28), whereas the HADS-D score was related to the HADS-A score (β=0.48, P<0.001), age (β=0.30, P<0.001), positive smoking status (β=0.13, P=0.004) and lack of exercise habit (β=0.12, P=0.008) (R2=0.31). Hypertension was related to waist circumference, history of parental hypertension and age (R2=0.38, P<0.001). Anxiety and depression scores were rejected as independent variables.

CONCLUSIONS:

Hypertension was associated with anxiety but not depression; however, age, history of parental hypertension and central obesity appeared to have a stronger association with hypertension in adults from Hong Kong.  相似文献   
40.
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