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51.
老年大鼠松质骨骨重建的组织形态计量学研究 总被引:1,自引:0,他引:1
目的:研究老年大鼠及在促骨合成药前列腺素E2(PGE2)作用下松质骨骨重建和骨建造的形态计量学改变,探讨动物骨重建形态学新参数测量方法及其意义。方法:50只20月龄雄性Wistar大鼠随机分成5组,年龄对照组(基础组、10d和30d年龄对照组),PGE2给药组(分别10d和30d给予3mg/kg/d处理组)。用体内双荧光标记,不脱钙组织切片,粘合线(cement line)染色,骨组织形态计量学方法,测定骨重建和骨建造参数。结果:20月龄雄性大鼠胫骨近端松质骨的形成表面大多数为骨重建单位(占63.3%),少部分为骨建造单位(占26.7%);PGE2用药后骨重建单位增加1.5倍,骨建造单位增加4倍,比值倒置,成骨细胞10d时明显增多。说明PGE2通过刺激成骨细胞骨合成而介民导骨建造性骨增加和骨重建性骨量增加,并以前为主。结论:老年雄性大鼠 松质骨以骨重建活动为主,仍有骨建造活动。PGE2主要通过刺激成骨细胞骨建造而增加骨量。 相似文献
52.
I. A. NÆSS S. C. CHRISTIANSEN† P. ROMUNDSTAD‡ S. C. CANNEGIETER† F. R. ROSENDAAL†§ J. HAMMERSTRØM 《Journal of thrombosis and haemostasis》2007,5(4):692-699
Background: Estimates of the incidence of venous thrombosis (VT) vary, and data on mortality are limited. Objectives: We estimated the incidence and mortality of a first VT event in a general population. Methods: From the residents of Nord‐Trøndelag county in Norway aged 20 years and older (n = 94 194), we identified all cases with an objectively verified diagnosis of VT that occurred between 1995 and 2001. Patients and diagnosis characteristics were retrieved from medical records. Results: Seven hundred and forty patients were identified with a first diagnosis of VT during 516 405 person‐years of follow‐up. The incidence rate for all first VT events was 1.43 per 1000 person‐years [95% confidence interval (CI): 1.33–1.54], that for deep‐vein thrombosis (DVT) was 0.93 per 1000 person‐years (95% CI: 0.85–1.02), and that for pulmonary embolism (PE) was 0.50 per 1000 person‐years (95% CI: 0.44–0.56). The incidence rates increased exponentially with age, and were slightly higher in women than in men. The 30‐day case‐fatality rate was higher in patients with PE than in those with DVT [9.7% vs. 4.6%, risk ratio 2.1 (95% CI: 1.2–3.7)]; it was also higher in patients with cancer than in patients without cancer [19.1% vs. 3.6%, risk ratio 3.8 (95% CI 1.6–9.2)]. The risk of dying was highest in the first months subsequent to the VT, after which it gradually approached the mortality rate in the general population. Conclusions: This study provides estimates of incidence and mortality of a first VT event in the general population. 相似文献
53.
54.
Transfusion practice in central Virginia 总被引:4,自引:0,他引:4
55.
Fleischer AC; Dudley BS; Entman SS; Baxter JW; Kalemeris GC; James AE Jr 《Radiology》1987,162(2):307-310
The depth of myometrial invasion by endometrial carcinoma was evaluated using real-time sonography (US) in 20 patients with histologically proved adenocarcinoma of the endometrium. In 14 of 20 (70%) cases, US-based estimation of the depth of myometrial invasion was within 10% of the actual measurement in the gross specimen. The US-based estimation of tumor invasion was low in seven patients, high in four patients, and agreed with pathologic findings (+/- 5%) in nine patients. In four patients with polypoid intraluminal extension of tumor, a deeply invasive tumor was suspected on US but was not found on pathologic examination. In 12 superficially invasive tumors, the continuity of the demarcating subendometrial halo was intact in nine and incomplete in three. In six patients with deeply invasive tumors, this zone was partially disrupted in four, totally disrupted in one, and intact in one. Errors of estimation of the depth of myometrial invasion on US most frequently occurred when a tumor had a significant intraluminal polypoid extension. Demonstration of a subendometrial halo usually indicated superficial invasion, whereas the absence of a halo was frequently associated with deep invasion. 相似文献
56.
B Airan Ch SK Choudhary M. Ch CSK Ready M. Ch A Saxena DM SS Kothari DM IM Rao M.Ch P Venugopal M.Ch 《Indian Journal of Thoracic and Cardiovascular Surgery》2000,16(1):15-18
Introduction The Fontan procedure has undergone many modifications to avoid atrial arrhythmias and thrombus formation. We used patient’s
interatrial septum as a flap to direct the inferior venacaval blood to the superior venacava.
Methods Seventeen patients, aged 1 to 17 years, underwent modified total cavopulmonary anastomosis. Interatrial septum was used to
create the inner half of the atrial tunnel, outer half being formed by right atrial free wall. Post-operatively, all patients
underwent echocardiography. Seven patients underwent 24 hour ambulatory Holter monitoring and 6 patients underwent cardiac
catheterization and cineangiography.
Results There was one early death due to low cardiac output. One patient had transient supraventricular arrhythmia. Two patients had
singnificant pleural effusion. Holter Monitoring reveled sinus rhythm in all 7 patients studied. Follow up ranged from 18
to 60 months and patients were evaluated as they came for follow up. Long term follow up is currently being compiled. There
was one late death from a non-cardiac cause. The remaining patients were in New York Heart Association (NYHA) Class I or II.
All patients were in sinus rhythm. Echocardiography and cineangiography revealed absence of obstruction or leak.
Conclusions Total cavopulmonary anastomosis using autogenous atrial septum is a useful modification for classical cavopulmonary anastomosis
and provides good early results. 相似文献
57.
Erin L. Simon DO Peter Griffin Kantha Medepalli Gregory GriffinCarolyn J. Williams MS Michael Hewit Thomas S. Lloyd 《The Journal of emergency medicine》2014
Background
Freestanding emergency departments (FEDs) introduce a challenge to physicians who care for the patient with an ST-segment elevation myocardial infarction (STEMI) because treatment is highly time dependent. FEDs have no percutaneous coronary intervention (PCI) capabilities, which necessitates transfer to a PCI-capable facility or fibrinolysis.Study Objective
Our aim was to determine the proportion of STEMI patients who arrived to an FED and were subsequently transferred for PCI and met the door-to-balloon reperfusion guidelines of 90 min.Methods
This was a dual-center retrospective cohort review of all patients 18 years and older who were diagnosed with an STEMI and presented to the main hospital−affiliated FEDs. Electronic medical records and emergency medical services documentation were reviewed for all cases since the opening of the FEDs in July 2007 and August 2009, respectively. Key time points were abstracted and statistical evaluation was performed using Fisher's exact test.Results
A total of 47 patients met inclusion criteria. Median door-to-transport time was 34 min (interquartile range [IQR] 15 min). Median transport time from the FEDs to the main hospital catheterization laboratory was 21 min (IQR 5 min). Median arrival at the catheterization laboratory-to-balloon time was 25 min (IQR 13 min). Median total door-to-balloon time was 83 min (IQR 10.5 min), with 78.7% meeting the American Heart Association's recommended guidelines of ≤ 90 min.Conclusion
STEMI patients initially seen at two FEDs achieved door-to-balloon time goals of < 90 min. 相似文献58.
ObjectiveTo assess and compare the risk factors in patients with benign gastric and duodenal ulcers and to correlate the prevalence of Helicobacter pylori (H. pylori) infection in benign peptic ulcer disease.MethodsA total of 30 consecutive patients with peptic ulcer disease were included in this study after upper gastrointestinal endoscopy. Their clinical profile and endoscopic findings were noted. Antral biopsies were subjected to histopathological examination and urease test for detection of H. pylori. Results were correlated. The study was cleared by the Institute Research Council and the Ethics committee.ResultsThe male: female ratio was 11:4. Overall, H. pylori infection was prevalent in 93.3% of the patients. Patients who took spicy food had a significantly higher rate of H. pylori positivity (P=0.04). Smoking, alcohol intake and NSAIDs did not affect H. pylori status in patients. There was no significant association between the site of the ulcer and H. pylori infection.ConclusionsBased on our observations we conclude that prevalence of H. pylori infection is similar in duodenal and gastric ulcers and intake of spicy food is a significant risk factor. 相似文献
59.
Liu SC; Palek J; Yi SJ; Nichols PE; Derick LH; Chiou SS; Amato D; Corbett JD; Cho MR; Golan DE 《Blood》1995,86(1):349-358
Southeast Asian ovalocytosis (SAO) is an asymptomatic trait characterized by rigid, poorly deformable red cells that resist invasion by several strains of malaria parasites. The underlying molecular genetic defect involves simple heterozygous state for a mutant band 3 protein, which contains a deletion of amino acids 400 through 408, linked with a Lys 56-to-Glu substitution (band 3-Memphis polymorphism). To elucidate the contribution of the mutant SAO band 3 protein to increased SAO red blood cell (RBC) rigidity, we examined the participation of the mutant SAO band 3 protein in increased band 3 attachment to the skeleton and band 3 oligomerization. We found first that SAO RBC skeletons retained more band 3 than normal cells and that this increased retention preferentially involved the mutant SAO band 3 protein. Second, SAO RBCs contained a higher percentage of band 3 oligomer-ankyrin complexes than normal cells, and these oligomers were preferentially enriched by the mutant SAO protein. At the ultrastructural level, the increased oligomer formation of SAO RBCs was reflected by stacking of band 3-containing intramembrane particles (IMP) into longitudinal strands. The IMP stacking was not reversed by treating SAO RBCs in alkaline pH (pH 11), which is known to weaken ankyrin-band 3 interactions, or by removing the cytoplasmic domain of band 3 from SAO membranes with trypsin. Finally, we found that band 3 protein in intact SAO RBCs exhibited a markedly decreased rotational mobility, presumably reflecting the increased oligomerization and the membrane skeletal association of the SAO band 3 protein. We propose that the mutant SAO band 3 has an increased propensity to form oligomers, which appear as longitudinal strands of IMP and exhibit increased association with membrane skeleton. This band 3 oligomerization underlies the increase in membrane rigidity by precluding membrane skeletal extension, which is necessary for membrane deformation. 相似文献
60.
Engraftment of bone marrow cells into normal unprepared hosts: effects of 5-fluorouracil and cell cycle status 总被引:2,自引:7,他引:2
Bone marrow from animals treated with 5-fluorouracil (5FU) competes equally with normal marrow when assessed in vivo in an irradiated mouse, but shows markedly defective engraftment when transplanted into noncytoablated hosts. Using Southern Blot analysis and a Y-chromosome specific probe, we determined the level of engraftment of male donor cells in the bone marrow, spleen, and thymus of unprepared female hosts. We have confirmed the defective engraftment of marrow harvested 6 days after 5FU (FU-6) and transplanted into unprepared hosts and shown that this defect is transient; by 35 days after 5FU (FU-35), engraftment has returned to levels seen with normal marrow. FU-6 marrow represents an actively cycling population of stem cells, and we hypothesize that the cycle status of the stem cell may relate to its capacity to engraft in the nonirradiated host. Accordingly, we have evaluated the cycle status of engrafting normal and FU-6 marrow into normal hosts using an in vivo hydroxyurea technique. We have shown that those cells engrafting from normal marrow and over 70% of the cells engrafting from FU-6 marrow were quiescent, demonstrating no killing with hydroxyurea. We have also used fluorescent in situ hybridization (FISH) analysis with a Y-chromosome probe and demonstrated that normal and post-5FU engraftment patterns in peripheral blood were similar to those seen in bone marrow, spleen, and thymus. Altogether these data indicate that cells engrafting in normal, unprepared hosts are dormant, and the defect that occurs after 5FU is concomitant with the induction of these cells to transit the cell cycle. 相似文献