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Carcinoembryonic antigen (CEA) has been extracted and purified by two different methods from a single aqueous homogenate of liver metastases from a primary adenocarcinoma of the colon, thus enabling direct comparison to be made between a conventional technique using gel filtration and a monoclonal antibody immunoadsorbent method. Yield, immunoreactivity and purity have been determined in both cases by direct weighing, enzyme-linked immunoadsorbent assay, radioimmunoassay and SDS-polyacrylamide gel electrophoresis. Reactivity of the antigen with monoclonal and polyclonal anti-CEA antibodies recognising different epitopes was analysed by Western blotting. There appears to be no significant difference in immunoreactivity or purity by these criteria, but the immunoadsorbent method gave a higher yield of CEA for far less expenditure of time and effort. A variant of CEA with a lower molecular weight was also identified in both preparations.  相似文献   
43.
STUDY OBJECTIVE: To determine whether buffered lidocaine must be prepared just before use. DESIGN: Randomized, double-blind, prospective trial. SETTING: University hospital. PARTICIPANTS: Twenty-four adult volunteers. INTERVENTIONS: Three buffered lidocaine solutions prepared seven days, one day, and just before use were compared with a control solution. Subjects received 0.5 mL intradermal injections of each solution. Pain of infiltration and extent and duration of anesthesia were measured. MEASUREMENTS AND MAIN RESULTS: Pain of infiltration was less with all buffered solutions than control (P less than .0001). Mean maximum diameter of anesthesia ranged from 29 to 33 mm for the buffered solutions compared with 31 mm for control. Mean duration of anesthesia was 33 minutes for control and 30 minutes for all of the buffered solutions. There was no statistically significant difference in extent or duration of anesthesia for any of the solutions (P greater than .5, beta = .15 for delta = 10%). CONCLUSION: Buffered lidocaine stays effective for up to one week after preparation. It is therefore convenient to use in emergency settings.  相似文献   
44.
Parkin mutations account for the majority of familial and sporadic early onset Parkinson's disease (EOPD) cases with a known genetic association. More than 100 mutations have been described in the Parkin gene that includes homozygous, compound heterozygous, and single heterozygous mutations. We have designed a Parkin mutation genotyping array (gene chip) that includes published Parkin sequence variants and allows their simultaneous detection. The chip was validated by screening 85 PD cases and 47 controls previously tested for Parkin mutations. Similar genotyping microarrays have been developed for other genetically heterogeneous diseases including age-related macular degeneration. Here, we show the utility of a genotyping array for Parkinson's disease by analysis of 60 subjects from the Genetic Epidemiology of Parkinson Disease (GEPD) study that includes 15 early-onset PD case probands and 45 relatives.  相似文献   
45.
Angiogenesis precedes recovery following spinal cord injury and its extent correlates with neural regeneration, suggesting that angiogenesis may play a role in repair. An important precondition for studying the role of angiogenesis is the ability to induce it in a controlled manner. Previously, we showed that a coculture of endothelial cells (ECs) and neural progenitor cells (NPCs) promoted the formation of stable tubes in vitro and stable, functional vascular networks in vivo in a subcutaneous model. We sought to test whether a similar coculture would lead to the formation of stable functional vessels in the spinal cord following injury. We created microvascular networks in a biodegradable two-component implant system and tested the ability of the coculture or controls (lesion control, implant alone, implant + ECs or implant + NPCs) to promote angiogenesis in a rat hemisection model of spinal cord injury. The coculture implant led to a fourfold increase in functional vessels compared with the lesion control, implant alone or implant + NPCs groups and a twofold increase in functional vessels over the implant + ECs group. Furthermore, half of the vessels in the coculture implant exhibited positive staining for the endothelial barrier antigen, a marker for the formation of the blood–spinal cord barrier. No other groups have shown positive staining for the blood–spinal cord barrier in the injury epicenter. This work provides a novel method to induce angiogenesis following spinal cord injury and a foundation for studying its role in repair.  相似文献   
46.
Bile duct calculi in patients with primary sclerosing cholangitis   总被引:1,自引:0,他引:1  
  相似文献   
47.
The development and implementation of effective community support systems are goals of many public mental health authorities who are attempting to shift the focus and dollars for mental health services from inpatient to community care. This article presents the results of a survey which asked 90 community mental health agency case managers to assess the community support and residential needs of over 1400 of their clients. Medication monitoring and therapy were rated high priority needs. Psychosocial treatment, day and vocational activities also ranked high. Survey responses regarding residential services indicated a need for more supported and supervised options.The study reported was a collaborative effort by county and agency staff.  相似文献   
48.
A 46-year-old man presented with shock and adult respiratory distress syndrome. Investigations revealed an adrenal mass that was diagnosed, by fine-needle aspiration biopsy, as pheochromocytoma. Because biopsy is contraindicated in patients with pheochromocytoma, this confusing presentation underscores the value of excluding this diagnosis by biochemical means before performing fine-needle aspiration of adrenal tumours.  相似文献   
49.
To determine the effect of MR imaging on the immune system, 21 male C57BL/6 X DBA/2 F1 mice were exposed to MR imaging at a field strength of 0.15 T for 2 hr. Another nine mice (controls) were sham exposed for the same amount of time. Mice were sacrificed and their spleens removed 24, 72, and 144 hr after the exposure (MR or sham). Spleen cell suspensions were passed over nylon wool columns and then used as effector cells in a short-term natural killer cell cytotoxicity assay with 51Cr-labeled YAC-1 cells as target cells. The results showed no evidence of decreased cytotoxicity due to exposure to MR. On the contrary, at all three times after exposure and for all target-to-effector cell ratios, mean cytotoxicity was greater for MR-exposed groups than for sham-exposed groups. The results show that MR exposure has no adverse effect on the immune system, as evidenced by natural killer cell activity.  相似文献   
50.
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