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991.
Causative diagnosis of pneumonia is problematic. The lack of a reliable gold standard for diagnosis has also made the development of new diagnostic methods for different microbes causing pneumonia difficult. Serologic methods are continuously used in the diagnosis of pneumonia caused by viruses and atypical bacteria. However, rapid diagnostic methods are urgently needed to guide clinicians to choose proper antibiotic treatment because resistant bacteria are emerging in different parts of the world.  相似文献   
992.
Immune response after laparoscopic and conventional Nissen fundoplication.   总被引:7,自引:0,他引:7  
OBJECTIVE: To compare the changes in the immune responses of patients undergoing laparoscopic or conventional Nissen fundoplication. DESIGN: Prospective randomised clinical study. SETTING: University hospital, Finland. SUBJECTS: 20 patients undergoing Nissen fundoplication for symptomatic erosive oesophagitis. INTERVENTION: Laparoscopic Nissen fundoplication (n = 10) or conventional open Nissen fundoplication (n = 10). MAIN OUTCOME MEASURES: Leucocyte and differential counts; percentages of lymphocyte subpopulations (CD3, CD4, CD8, CD16 and CD20 positive lymphocytes); and monocytes (CD 14); phytohemagglutinin, concanavalin A and pokeweed mitogen-induced and unstimulated proliferation of separated lymphocytes; plasma interleukin-6 (IL-6), serum C-reactive protein (CRP), albumin, and cortisol concentrations; and group II phospholipase A2 (PLA2) activity. RESULTS: Laparoscopic fundoplication was associated with less tissue damage (IL-6, and CRP concentrations) than the conventional open operation. However, although there were pronounced changes in immune responses over time, there were no differences between the groups. CONCLUSION: Laparoscopic fundoplication seemed to cause less tissue damage than the conventional open operation, but this difference was not reflected in patients' immune responses.  相似文献   
993.
An organ culture model of four bovine anterior cruciate ligaments was used to compare synovial fluid with bovine serum, lactated Ringer's solution, and Basal Medium Eagle's (BME) to determine their relative abilities to support in vitro conversion of proline into hydroxyproline. There was no difference between serum and synovial fluid in their ability to support collagen synthesis. These results suggest that bovine synovial fluid is not inhibitory in that it is similar to bovine serum in supporting ligament collagen synthesis under the conditions described.  相似文献   
994.
Serum acid phosphatase levels were determined in 247 men with surgically confirmed intracapsular prostatic cancer (30 patients), benign prostatic hyperplasia (BPH) (114 patients) or palpably normal prostates (103 men). Both radioimmunoassay (245 cases) and an enzymatic method (218 cases) were used. Using radioimmunoassay, the mean serum prostatic acid phosphatase (PAP) level was significantly higher in patients with BPH than in patients with intracapsular cancer or men with normal prostates. The weight of hyperplastic tissue removed during operation in the BPH group correlated closely with PAP concentrations. Age or the presence (or absence) of an indwelling catheter had no effect on PAP concentration. Using the enzymatic method, the highest levels of acid phosphatase were also detected in patients with BPH but the difference was less marked. It was concluded that intracapsular cancer does not elevate serum acid phosphatase levels as determined by radioimmunoassay or an enzymatic method. BPH alone leads to significant rises in PAP concentrations. The degree of BPH correlates with PAP levels.  相似文献   
995.
After cranial subcutaneous injection of lidocaine 0.8–3.7 mg/kg+ adrenaline (epinephrine) 1:200,000 in neurosurgical patients, fast drug absorption was found with peak plasma concentrations of 0.6–1 μg/ml in 5–10 min. However, the concentrations remained above the lowest effective antiarrhythmic level of 0.6 μg/ml for only about 10 min. In one patient, simultaneously administered intravenous lidocaine had an additive effect on those levels. Induced hypotension (sodium nitroprusside) during aneurysm operations decreased the arterial plasma level of lidocaine and was followed by a new peak after discontinuation. Thus the absorption of a drug during induced hypotension from subcutaneous tissue is often erratic.  相似文献   
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Diem  C; Runger  TM 《Carcinogenesis》1997,18(4):657-662
In order to study the role of DNA damage processing in the development of cutaneous squamous cell carcinoma (SCC), we assessed the ability of six keratinocyte cell lines from a multistage-tumor progression model to repair three types of DNA damage: pyrimidine dimers, oxidative DNA lesions and DNA double strand breaks (DSB). The model comprised the spontaneously immortalized, non-tumorigenic human keratinocyte cell line HaCaT, four different c-Ha-ras transfectants of HaCaT (non-, benign- and two malignant-tumorigenic) and a SCC-derived cell line. Host cell reactivation assays with UVB-treated plasmid vectors pRSVcat showed no significantly altered repair of UVB-induced pyrimidine dimers in the tumorigenic cell lines, compared with the non-tumorigenic lines. Using the singlet oxygen-treated plasmids pRSVcat the Ha-ras-HaCaT- clones and the SCC-cells, exerted a DNA repair efficiency that was not significantly different from HaCaT cells. In order to assess the ability of the cells to ligate free DNA ends (repair of DSB), we used a plasmid shuttle vector assay with linearized plasmid pZ189. We found a significant increase of DNA end joining ability in the non-tumorigenic, the benign and in one of the malignant HaCaT-clones II-4. The malignant HaCaT-clone II-3, however, exerted a significantly lower rate of rejoining the linearized plasmid. This cell line also showed a highly and significantly elevated rate of micronuclei, which reflects a pronounced chromosomal instability. The SCC-cells exhibited a more efficient repair of DNA DSB than the HaCaT cells. We conclude that in the examined model, progression of human keratinocytes from the non- tumorigenic to the highly tumorigenic phenotype, is not accompanied by a decrease in the cell's capacity to repair UVB- and singlet oxygen- induced DNA lesions. However, an acquired deficiency in repairing DNA double strand breaks can be one mechanism promoting progression towards malignancy, possibly through impairing chromosomal stability.   相似文献   
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