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61.
生物软组织可视为具有多层次结构的织构复合水凝胶体系(TCHS)、以水凝胶复合元件(HCE)为基本的构件(CP),通过一定的组合、排列方式构筑一系列多层次结构的不同软组织。软组织中任何层次的结构单元既可视为织构复合水凝胶体系又可视为构件。任何层次的TCHS中,构件的结构及其组合排列方式决定着该层次单元的功能。以织构复合水凝胶体系的观点考察了真核细胞、角膜和骨骼肌的多层次结构。双层网络水凝胶、皮芯复合水凝胶纤维人工肌肉模型、时空匹配可降解细胞支架等研究成果初步地证明了提出织构复合水凝胶体系观点的合理性。  相似文献   
62.
The pharmacology of a new pasteurized factor VIII (FVIII) concentrate derived from human blood plasma was studied in 23 adults with hemophilia A. In Part 1 of the study involving six nonbleeding subjects, the mean increase in FVIII activity was 1.43 +/- 0.34 U per ml 10 minutes after an intravenous dose of 50 U per kg. The intravascular survival kinetics in these six patients showed a biphasic decay curve with an initial mean half-life of 5.1 +/- 1.2 hours probably representing early redistribution, and a late half-life of 13.3 +/- 4.9 hours. In Part 2 of the study, the activity at 10 minutes was measured in another 17 patients, as well as in one patient already studied in Part 1. The mean increase in activity with the 24 observations was 1.13 +/- 0.37 U per ml with a mean FVIII dosage of 51.0 +/- 2.6 U per kg of body weight. Only one patient had an allergic reaction, which did not recur when the patient was given a second lot.  相似文献   
63.
Percutaneous umbilical blood samples (PUBS), obtained under ultrasound guidance, are used for prenatal diagnosis and management of hemolytic disease of the newborn (HDN) and other fetal disorders. Rapid testing at the time of sampling is vital to distinguish fetal from maternal blood. Blood typing was performed by slide technique in the treatment room during 38 procedures on 25 patients. Anti-I was used to test 50 presumed PUBS; venous I-positive maternal blood was tested in parallel. Because anti-I cannot detect fetal blood after umbilical vein transfusion (UVT) of I-positive donor blood, ABO and Rh blood typing reagents were used to test 29 samples when maternal and fetal or donor blood groups differed. Monoclonal reagents were used for optimal detection of weak AB antigens in fetal blood. Avid, chemically modified anti-D was used for Rh typing. Blood typing showed 27 (34%) of 79 samples to be maternal blood. Fetal blood was obtained in 8 of 10 cases investigated for fetal disorder and in 16 cases of potential HDN (anti-D, 5; -CD, 5; -cE, 2; -K, 2; -c; -E). The absence of HDN (antigen-negative fetus) was determined in 4 cases. UVT afforded live birth of 9 of 10 infants with HDN and was not indicated in two cases.  相似文献   
64.
The overrepresentation of persons with mental illnesses in the criminal justice system is well documented. As more communities attempt to offer appropriate evidence-based practices in diversion and reentry programs, a major issue that has become apparent is that adaptations to the standard practices are often required because of the legal predicaments faced by clients. The associated question is how extensive can adaptations be before fidelity to the proven practice is compromised. To better understand these pressing issues, the National GAINS Center for Evidence-Based Programs in the Justice System held a series of six meetings focused on evidence-based practices (assertive community treatment, housing, trauma interventions, supported employment, illness self-management and recovery, and integrated treatment) and their applicability for persons involved in the criminal justice system. This Open Forum integrates the results of those meetings and proposes future steps to establish relevant evidence-based practices that can influence both behavioral health and public safety outcomes for persons involved with the criminal justice system.  相似文献   
65.
Purpose: To retrospectively examine the optic disc photographs of a glaucoma population for optic disc haemorrhages, vascular occlusions and vascular abnormalities. Methods: The optic disc photographs of 906 eyes of glaucoma and suspect glaucoma patients were examined. Optic disc photographs were taken annually, where possible, with the follow-up period varying between 1 and 14 years duration (mean, 2.89). Glaucoma patients are regularly reviewed every 4–6 months and glaucoma suspects every 1–2 years, depending on the ophthalmologist. Low-tension glaucoma patients were reviewed more frequently (mean, every 2.6 months). The results of the findings were compared to a control group of 39 subjects with a mean follow-up period of 7 years, using Fisher's exact test. Results: It was found that during the period under review, 7.4% (n= 67) of eyes had optic disc haemorrhages. The highest frequency of optic disc haemorrhages (37.5%) was found in the low tension glaucoma group (P= 0.0001) followed by 11.4% of primary open-angle glaucoma eyes (P= 0.03). In the normal group there were three eyes with optic disc haemorrhages and one with a disc collateral, which constitutes 5.1% vascular changes in this sub-group. Of the study eyes 2.8% had central retinal vein occlusions, 1.3% branch vein occlusion, 1.2% disc vessel abnormalities (loops) and 1.1% disc collaterals. Discrete nerve fibre layer haemorrhages and microaneurysms were found in 0.8% and 1.8% of eyes, respectively. Conclusions: A total of 16.8% of the eyes observed in this study had either disc haemorrhages or vascular changes. The underlying trend of vascular and haemorrhagic changes in glaucoma are demonstrated in this sample, which is in general agreement with previous studies. The high percentage of optic disc haemorrhages in low tension glaucoma is highlighted. The presence of microaneurysms and nerve fibre layer haemorrhages is interesting but of unknown significance.  相似文献   
66.
In chronic inflammatory diseases, cytokines stimulate the hypothalamus pituitary adrenal axis and the hypothalamus autonomic nervous system (HANS) axis. The present study was performed to find autonomic nervous function parameters in patients with systemic lupus erythematosus (SLE) which are suitable to demonstrate the activation of the HANS axis during systemic inflammation. Thirty-four patients with SLE (age 35.3 +/- 1.9 yr) were investigated by seven standardized autonomic nervous function tests. The SLEDAI and laboratory parameters of systemic inflammation were assessed by standard techniques. Pupillary latency time hyperreflexia was found in 29.4%, whereas maximal pupillary area was hyperresponsive in only 2.9%. A total of 12% had overall cardiovascular autonomic nervous hyperreflexia. Patients with latency time hyperreflexia had more severe systemic inflammation [erythrocyte sedimentation rate (ESR): P < 0.001; C-reactive protein (CRP): P = 0.0094; fibrinogen: P < 0.001; albumin: P = 0.003; antinuclear antibodies: P = 0.020]. The longitudinal study of 13 patients during 4 yr demonstrated a parallel increase and decrease in latency time percentile and ESR. SLE patients with increased systemic inflammation had an activated HANS axis which can be measured by a parasympathetic pupillary reflex test.   相似文献   
67.
The effectiveness of coronary venous retroperfusion treatment of an ischemic myocardial segment was assessed by measurements of regional and global myocardial function in 16 dogs. The left anterior descending coronary artery was acutely occluded for 75 minutes. After the first 30 minutes of occlusion, diastolic retroperfusion was instituted for 45 minutes by synchronized pumping of arterial blood from the brachial artery into the anterior interventricular coronary vein. Data collected in the preocclusion control period, during occlusion and the subsequent retroperfusion period included simultaneous measurement os ischemic and border zone myocardial forces, epicardial electrocardiographic S-T segments, intracoronary pressure, coronary blood flow and oxygen pressure (PO2) sampled distal to the site of occlusion. Retroperfusion resulted in significant improvement from the level of regional dysfunction observed after 30 minutes of occlusion: Ischemic zone myocardial force increased 106%, epicardial S-T elevation decreased 46%, normalized peripheral left anterior descending coronary arterial flow increased 50% and distal left anterior descending PO2 decreased 44%. These regional improvements were significant when compared with findings in an untreated series of 12 dogs with 75 minutes occlusion of the left anterior descending coronary artery. Diastolic-augmented coronary venous retroperfusion with arterial blood provided significant but not complete restoration of function in the ischemic segment. Therefore, in the earliest phase of acute myocardial infarction, retroperfusion might represent a useful temporary support to an otherwise inaccessible jeopardized zone of the heart. Regional retroperfusion may constitute an effective emergency procedure, particularly when the occlusive lesions are diffuse and other medical or surgical emergency procedures are inadvisable, unavailable or ineffective.  相似文献   
68.
Stabler  SP; Lindenbaum  J; Savage  DG; Allen  RH 《Blood》1993,81(12):3404-3413
Homocysteine can be methylated to form methionine by the cobalamin- (Cbl) and folate-dependent enzyme, methionine synthase; serum levels of total homocysteine are elevated in greater than 95% of patients with either Cbl or folate deficiency. Homocysteine can also condense with serine to form cystathionine in a pyridoxal phosphate-dependent reaction catalyzed by cystathionine beta-synthase. Cystathionine is subsequently cleaved to cysteine and alpha-ketobutyrate by the pyridoxal phosphate-dependent enzyme gamma-cystathionase. To assess levels of cystathionine in Cbl and folate deficiency, we developed a new capillary gas chromatographic-mass spectrometric assay and measured cystathionine in the serum of normal subjects and patients with clinically confirmed deficiencies of these vitamins. The normal range for serum cystathionine was 65 to 301 nmol/L (median = 126 nmol/L) for 50 normal blood donors. In 30 patients with clinically confirmed Cbl deficiency, values for cystathionine ranged from 208 nmol/L to 2,920 nmol/L (median = 816 nmol/L) and 26 (87%) had levels above the normal range. In 20 patients with clinically confirmed folate deficiency, cystathionine concentrations ranged from 138 nmol/L to 4,150 nmol/L (median = 1,560 nmol/L) and 19 (95%) had values above the normal range. Five homozygotes for cystathionine beta-synthase deficiency had high values for serum-total homocysteine and low or low-normal values for serum cystathionine that ranged from 30 nmol/L to 114 nmol/L even though they were on treatment with pyridoxine and had partially responded. One patient with a defect in the synthesis of 5-CH3- tetrahydrofolate and five patients with defects in the synthesis of CH3- Cbl had high values for serum-total homocysteine and high values for cystathionine that ranged from 311 nmol/L to 1,500 nmol/L even though they were on treatment with folic acid and Cbl, respectively, and had partially responded. We conclude that levels of cystathionine are evaluated in the serum of most patients with Cbl and folate deficiency and that they are useful in the differential diagnosis of an elevated serum-total homocysteine level.  相似文献   
69.
Composites are increasing in popularity as restorative materials. This growing role indicates the necessity of studies on their clinical outcome. In this study, clinical studies published on the performance of posterior composite restorations were included except those of less than a 24‐month assessment period. Results of non‐vital, anterior or primary teeth and cervical single‐surface restorations were also excluded. Records about composite type, number of final recall restorations, failure/survival rate, assessment period and failure reasons were analysed for each decade. Overall survival/failure rates for studies in 1995–2005 were 89.41%/10.59% and for 2006–2016 were 86.87%/13.13%, respectively. In 1995–2005, the reasons for failure were secondary caries (29.47%) and composite fracture (28.84%) with low tooth fracture (3.45%) compared with reasons of failure in 2006–2016, which were secondary caries (25.68%), composite fracture (39.07%), and tooth fracture (23.76%). An increase in incidence of composite fracture, tooth fracture and need for endodontic treatment as failure reasons was noted in the latter decade in addition to a decrease in secondary caries, postoperative sensitivity, unsatisfactory marginal adaptation and wear. The overall rates of failure showed little difference, but the causes showed a notable change. This is believed to be a reflection of increased use of composites for larger restorations and possibly changes of material characteristics.  相似文献   
70.
Twenty-six patients with progressive Hodgkin's disease after conventional chemotherapy received intensive chemoradiotherapy and autologous bone marrow transplantation (ABMT); 19 also received additional involved-field radiotherapy. Twenty-one patients [81%, 95% confidence intervals (CI) 61% to 94%] attained complete (n = 18) or partial responses. Ten patients (38%, 95% CI 20% to 59%) are disease- free a median of 4.5 years later (range 3.5 to 7.0 years), including seven patients with continuous complete responses. The likelihood of overall response was not significantly influenced by any clinical or treatment variable examined. However, there was a trend favoring patients with higher Karnofsky scores, and higher scores were associated with attainment of complete responses (P = .06 and P = .02, respectively, Mann-Whitney U test). Both higher Karnofsky scores and shorter durations of disease before transplantation were associated with improved survival in a stepwise Cox multivariate analysis. The chief cause of failure was progression at sites previously involved with Hodgkin's disease. No patient relapsed in the marrow, and two of three patients with a history of marrow involvement with Hodgkin's disease achieved durable complete responses after transplantation. These data suggest that inadequate pretransplant conditioning, and not the reinoculation of occult tumor cells in the autologous marrow, caused most relapses. Fatal treatment-related toxicity occurred in six patients. Three patients died of idiopathic interstitial pneumonitis; each had previously received local mediastinal irradiation before intensive chemoradiotherapy. Intensive chemoradiotherapy and ABMT produces durable responses in some patients with Hodgkin's disease incurable with conventional therapy. Use of such therapies at the first sign of failure with conventional chemotherapy and development of more effective conditioning regimens should further improve results.  相似文献   
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