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31.
We have recently shown using dansyl-L-lysine exclusion studies that the release of human chorionic gonadotrophin (HCG) in conjunction with L- lactate dehydrogenase (LDH) from first trimester villi during organ culture is symptomatic of syncytiotrophoblast degeneration. The purpose of this study was to examine chorionic villi at the ultrastructural level in order to determine events occurring during organ culture. The tissue was sampled after 0, 24, 48 and 120 h in culture and processed for electron microscopy. In addition to confirming the previously recorded syncytial degeneration, the electron micrographs showed clearly the generation of a new syncytiotrophoblast layer. The new layer, derived from differentiating cytotrophoblast cells, was largely formed by 48 h and was maintained for at least 120 h in culture. This study demonstrates a model which provides an opportunity to study the differentiation of cytotrophoblast cells whilst they retain their anatomical relationships within the villous structure.   相似文献   
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目的 探讨勃脉力A注射液对体外循环心脏手术患者肝功能的影响.方法 选择术前肝功能正常、无肝炎病史的行体外循环心脏手术患者60名,随机分为勃脉力A组(P组)和林格液组(R组).所有患者均在术前、术后2h、1d、3d、7d分别采肘正中静脉血和挠动脉血:静脉血分离血清后应用自动血生化分析仪检测血清中天冬氨酸转氨酶和丙氨酸氨基转移酶,以了解患者的肝脏功能改变;抽取动脉血查乳酸浓度.术中及术后密切观察患者血压、心率、中心静脉压、尿量等,观察并记录患者拔管及停留ICU时间.结果 与R组相比较,在术后各时间点P组ALT、AST及乳酸浓度均显著降低(P﹤0.05),并且拔除气管导管时间和停留ICU时间均有所缩短.结论 勃脉力A注射液能够显著降低体外循环术中乳酸浓度,并能改善患者肝功能,非常适用于体外循环手术.  相似文献   
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BACKGROUND: Joint consultation sessions of a small group of general practitioners (GPs) and a specialist in orthopaedics proved to be an effective way of decreasing the referral rate of orthopaedic patients. Cardiac complaints comprise an important category of health problems with high referral rates. AIMS: To study the effects of joint consultation on the quality of care and referrals for patients with cardiac complaints. DESIGN OF STUDY: Randomised controlled trial. SETTING: Forty-nine GPs participated in 16 consultation groups, each with one of 13 cardiologists, in monthly joint consultations over a period of about 18 months. METHOD: The GPs selected patients about whom they were uncertain, and those needing urgent referral were excluded. Patients were randomly assigned to joint consultation or to usual care. After a follow-up period all patients had a joint consultation for outcome assessment. Referral data were provided by two regional health insurance companies and questionnaires were given to the patients, GPs, and cardiologists to gauge their opinion of the trial. RESULTS: One hundred and forty-eight patients in the intervention group and 158 patients in the control group fulfilled the whole protocol. The quality of care was similar in both groups. In the intervention group, 34% of the patients were referred, compared with 55% in the control group (P = 0.001), and fewer patients underwent further diagnostic procedures (7% compared with 16%, P = 0.013). Referrals to cardiology as a proportion of all referrals decreased in the practices of the participating GPs, compared with their reference districts (P = 0.024). CONCLUSION: Joint consultation is an effective method that provides a quality of care that at least equals usual care and that contributes to a better selection of patients who need specialist care.  相似文献   
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Background  The goal of this study was to test whether myocardial triglyceride (TG) turnover including oxidation of TG-derived fatty acids (FA) could be assessed with PET and 11C-palmitate. Methods and Results  A total of 26 dogs were studied fasted (FAST), during Intralipid infusion (IL), during a hyperinsulinemic-euglycemic clamp without (HIEG), or with Intralipid infusion (HIEG + IL). 11C-palmitate was injected, and 45 minutes were allowed for labeling of myocardial TG pool. 3D PET data were then acquired for 60 minutes, with first 15 minutes at baseline followed by 45 minutes during cardiac work stimulated with constant infusion of either phenylephrine (FAST, n = 6; IL, n = 6; HIEG + IL, n = 6) or dobutamine (FAST, n = 4; HIEG, n = 4). Myocardial 11C washout during adrenergic stimulation (AS) was fitted to a mono-exponential function (Km(PET)). To determine the source of this 11C clearance, Km(PET) was compared to direct coronary sinus-arterial measurements of total 11C activity, 11C-palmitate, and 11CO2. Before AS, PET curves in all groups were flat indicating absence of net clearance of 11C activity from heart. In both FAST groups, AS resulted in negligible net 11C activity and 11CO2 production higher than net 11C-palmitate uptake. AS with phenylephrine resulted in net myocardial uptake of total 11C activity and 11C-palmitate in IL and HIEG + IL, and 11CO2 production lower than 11C-palmitate uptake. In contrast, AS with dobutamine in HIEG resulted in net clearance of all 11C metabolites (total 11C activity, 11C-palmitate and 11CO2) with 11CO2 contributing 66% to endogenous FA oxidation. The AS resulted in significant Km(PET) in all the groups, except HIEG + IL. However, positive correlation between Km(PET) and 11CO2 was observed only in HIEG (R 2 = 0.83, P = .09). Conclusions  This is the first study to demonstrate that using PET and pre-labeling of intracardiac TG pool with 11C-palmitate, noninvasive assessment of myocardial TG use is feasible under metabolic conditions that favor endogenous TG use such as increased metabolic demand (β-adrenergic stimulation of cardiac work) with limited availability of exogenous substrate (HIEG).  相似文献   
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The survival of transfused red cells (RBCs) diminishes with time of in vitro storage in blood banks, but the molecular mechanisms underlying the slow but incessant deterioration are incompletely understood. To investigate the possibility that impaired resistance to autologous complement attack could play a role in this phenomenon, packed RBCs stored for variable periods were assayed for decay-accelerating factor (DAF) and CD59, two glycoinositol-phospholipid (GPI)-anchored, membrane- associated complement regulatory proteins that function physiologically to protect blood cells from autologous complement activation on their surfaces. Immunoradiometric and flow cytometric assays employing DAF and CD59 monoclonal antibodies showed that levels of both surface proteins gradually declined over 6 weeks. Digestion analyses with phosphatidylinositol-specific phospholipase C, an enzyme that releases GPI-anchored proteins from cell surfaces, showed that DAF and CD59 molecules with GPI anchors containing unacylated inositol were preferentially lost. These findings suggest: 1) that DAF and CD59 molecules with acylated GPI anchors are more stable in RBC membranes than are molecules with unacylated GPI anchors, and 2) that DAF and CD59 loss may participate with other membrane alterations that occur during in vitro storage in compromising the survival of transfused cells.  相似文献   
38.

Objective

To evaluate the difference in thickness of the anterior vaginal wall removed after different surgical dissecting techniques of anterior colporrhaphy.

Study design

In patients undergoing primary anterior colporrhaphy, trimmed vaginal tissue was taken following different surgical techniques of vaginal wall dissection. Tissues were preserved in formalin and stained with hematoxylin-eosin and elastica-van Giesen stains. The examiner was an experienced pathologist blinded to the surgical technique. The specimens were examined for the epithelial thickness (ET), lamina propria thickness (LPT), muscular layer thickness (MT) and total thickness (TT).

Results

Tissue was analysed in 93 women who underwent anterior compartment pelvic organ prolapse surgery. There was no difference between the different surgical techniques in thickness measured in the three histological layers and for the total thickness. The use of hydrodissection was the only independent factor leading to thicker removed vaginal tissue.

Conclusions

Dissecting the vaginal wall as thin as possible does not result in a thinner vaginal layer than dissecting in the most optimal surgical plane. The use of hydrodissection provides a thicker trimmed tissue.  相似文献   
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