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81.
Outcome analysis in 654 surgically treated lumbar disc herniations.   总被引:10,自引:0,他引:10  
This article reports the outcomes of 654 consecutive patients treated during a 4.5-year period. Patients had a microdiscectomy, a laminectomy plus microdiscectomy, or a decompressive laminectomy with a microdiscectomy. The causes of ruptured discs were lifting (31.4%), falls (10.2%), and sports (10.0%). Almost all patients had complained of leg pain (99%), and 79% had radicular pain in a dermatomal distribution. Thirty-three percent of the patients had been involved in industrial accidents, and 6% had legal claims pending during the surgical period. Almost 11% of the patients had complications, and there was one death caused by abdominal arterial bleeding. Patients were also rated according to the Prolo Functional-Economic Outcome Rating Scale to improve the ability to compare series in the future. Almost 80% of the patients had good outcomes as defined by scores on this scale of 8 (16.2%), 9 (33.2%), and 10 (26.9%). Several conclusions can be drawn from the results of this series: 1) most patients had good outcomes; 2) patients with nonindustrial injuries had better outcomes than did patients with industrial injuries; 3) professionals with legal concerns and laborers with industrial insurance had good outcomes; and 4) the Functional-Economic Outcome Rating Scale appears to be a useful tool for comparing different procedures more objectively and for comparing the outcomes across series.  相似文献   
82.
Spontaneous apoptosis in germinal-centre (GC) B cells can be prevented by treatment with anti-immunoglobulin (Ig). By contrast, susceptible group-I Burkitt lymphoma (BL) cells can be driven to apoptosis by anti-Ig. The second-messenger pathways involved in the regulation of apoptosis in GC B lymphocytes and in BL cell lines were studied using pharmacological agonists or inhibitors of intracellular calcium ([Ca2+]i) and protein kinase C (PKC). Anti-Ig was found to mobilize Ca2+ in group-I cells. Pre-incubation with the Ca2+ chelator EGTA partially reduced apoptosis induced by anti-Ig or by Ca2+ ionophore in group-I BL cells. Activation of PKC with phorbol ester reduced such Ca(2+)-driven programmed cell death (PCD) to control levels of apoptosis. Apoptosis in group-I BL cell lines could also be triggered by the kinase inhibitors staurosporine and Ro-31-8220 at concentrations selective for PKC activity. Expression of the bcl-2 protein in BL group-I cells following gene transfer affords protection from apoptosis induced by ionomycin or anti-Ig. In the present study, bcl-2 was additionally found to protect from apoptosis driven by staurosporine. The high levels of spontaneous apoptosis exhibited by normal GC B cells were reduced, but not abrogated, by co-culture with phorbol ester. These results indicate that, in group-I BL cells, imbalance in the phosphoinositide pathway of signalling, in favour of [Ca2+]i and away from PKC, results in apoptosis: constitutive phosphorylation of key proteins by PKC may therefore suppress apoptosis in BL as well as in GC B cells.  相似文献   
83.
cAMP production was investigated in retinal pigment epithelium (RPE) cells isolated from normal rats and from rats with an inherited retinal dystrophy (Rdy/p+). In normal RPE cells, 5'-[N-Ethylcarboxamido]-adenosine (A2 receptors) produced a fivefold increase in the level of cyclic adenosine monophosphate (cAMP) over basal levels. However, only a onefold increase in cAMP was observed in dystrophic cells. cAMP production by prostaglandins E1 and E2 (prostaglandin receptors) in dystrophic RPE cells was only 29-38% of the level observed in normal cells. Direct stimulation of adenylyl cyclase by 10 mumol/l forskolin increased cAMP levels in normal RPE cells by 90 fold over basal, but only by sixfold in the dystrophic cells. These data suggest there may be a defect in the adenylyl cyclase signaling pathway in dystrophic RPE cells.  相似文献   
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Summary:  B-cell development is a highly ordered multistep process dependent upon signals generated by the pre-B and B-cell antigen receptor (BCR). BCR signals drive maturation of the B cell by integrating a number of parallel and sequential biological processes that result in generation of fully immunocompetent B cells. Among these biological processes are positive selection through several developmental checkpoints, negative selection of potentially self-reactive B cells, and activation of the mature B cell. In addition, recent studies have shown that developing and mature B cells rely on the constant activity of the BCR for their continued survival. Ligand (antigen)-dependent and -independent mechanisms of BCR signaling have been proposed, but their specific contributions to B-cell maturation and differentiation in the bone marrow and periphery are not completely clear. We discuss here a model, whereby ligand-independent basal BCR activity would be sufficient to trigger B-cell development through to the mature stage. However, long-term survival and formation of specific mature B-cell populations may be dependent on ligand–receptor interactions.  相似文献   
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The outcome for 758 consecutive patients who had received one or more chemotherapy regimens for recurrent or metastatic breast cancer is presented. The response rate following first line treatment was 34%. Median duration of response was 7.8 months, median time to progression was 3.7 months and median survival was 7.9 months. The only factor predicting for response, of factors recorded at presentation and at initiation of chemotherapy, was the use of anthracycline based regimens, though this may reflect the patient selection policy. Initial disease free interval, presence of liver metastases and use of anthracyclines were significantly related to time to progression. Several factors related to survival following first chemotherapy, but anthracycline usage showed only a very weak correlation. One third of patients (249/758) received two or more chemotherapy regimens. The response rate (16%) and median time to progression (2.3 months) were significantly worse than for first line treatment. The outcome after third line chemotherapy was very similar to that observed following second line treatment. Achievement of an objective response with first line chemotherapy predicted for second response, but with insufficient power to be of use in selecting patients for subsequent chemotherapy. Time to progression following first line chemotherapy did not influence that after second line treatment.  相似文献   
90.
The objective of this study was to test the impact of entacapone (ENT) addition to levodopa with a decarboxylase inhibitor (LD) in full-time-employed patients with Parkinson's disease (PD), focusing on retirement rates, medical absenteeism, self-perception of disability, as well as motor assessments of parkinsonism, motor fluctuations, and dyskinesias. Thirty full-time-employed PD patients (disease onset before age 60 years) and on optimized monotherapy with LD exhibiting minor motor fluctuations or dyskinesias were entered into a 2-year randomized double-blind placebo-controlled study of ENT adjunctive therapy. The outcome measures were the number of full-time-employed patients at study end, cumulative days of medical absenteeism, patient-completed disability assessments, diary records, and the Unified Parkinson's Disease Rating Scale-based measures of motor fluctuations and dyskinesias. LD + ENT treatment was associated with a lower retirement rate (2 [17%] of 12 vs. 6 [50%] of 12; P = 0.12), lower absenteeism rate (21.5 vs. 43.5 days; P < 0.0001), improved self-perception of disability progression over 2 years (change score 1.0 vs. 4.5; P < 0.0001), and lower scores for both motor fluctuations and dyskinesia assessments compared to LD monotherapy. In this pilot study, LD with ENT adjunctive therapy positively influenced employment rate over 2 years; this effect was associated with reduced motor complications and patient perceptions of stabilized disability.  相似文献   
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