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41.
Aggressive surgical management of spinal metastatic disease can provide improvement of neurological function and significant pain relief. However, there is limited literature analyzing such management as is pertains to individual histopathology of the primary tumor, which may be linked to overall prognosis for the patient. In this study, clinical outcomes were reviewed for patients undergoing spinal surgery for metastatic breast cancer. Respective review was done to identify all patients with breast cancer over an eight-year period at a major cancer center and then to select those with symptomatic spinal metastatic disease who underwent spinal surgery. Pre- and postoperative pain levels (visual analog scale [VAS]), analgesic medication usage, and modifed Frankel grade scores were compared on all patients who underwent surgery. Univariate and multivariate analyses were used to assess risks for complications. A total of 16,977 patients were diagnosed with breast cancer, and 479 patients (2.8%) were diagnosed with spinal metastases from breast cancer. Of these patients, 87 patients (18%) underwent 125 spinal surgeries. Of the 76 patients (87%) who were ambulatory preoperatively, the majority (98%) were still ambulatory. Of the 11 patients (13%) who were nonambulatory preoperatively, four patients were alive at 3 months postoperatively, three of which (75%) regained ambulation. The preoperative median VAS of six was significantly reduced to a median score of two at the time of discharge and at 3, 6, and 12 months postoperatively (P < 0.001 for all time points). A total of 39% of patients experienced complications; 87% were early (within 30 days of surgery), and 13% were late. Early major surgical complications were significantly greater when five or more levels were instrumented. In patients with spinal metastases specifically from breast cancer, aggressive surgical management provides significant pain relief and preservation or improvement of neurological function with an acceptably low rate of complications.  相似文献   
42.
Both AVP and dDAVP effect a transient increase in cytosolic free calcium (iCa2+) in cortical collecting tubule (CCT) cells. To investigate the physiological role of this increase in iCa2+, we examined the effect of TMB-8, a putative inhibitor of iCa2+ release, on the initial and sustained phase of AVP- and dDAVP-stimulated water permeability (Pf) in isolated, perfused CCTs. Pretreatment of tubules with TMB-8, 50 microM, suppressed the increase in osmotic water permeability (Pf) induced by 10 microU/ml AVP and dDAVP, but had no effect on the sustained phase of the response. When increased to 100 microM. TMB-8 inhibited the sustained phase of AVP action. A similar pattern was observed on AVP-stimulated adenyly cyclase activity in rabbit renal membranes. Pretreatment of tubules with 50 microM TMB-8 attenuated the initial increase in Pf in response to cholera toxin but not to 8-Br-cAMP or forskolin. There was no effect of this concentration of TMB-8 on the sustained phase of these agonists. These studies suggest that, in lower concentrations, TMB-8 inhibits the mobilization of iCa2+, which is important for the interaction of Gs with the catalytic unit of adenylyl cyclase and the initial increase in AVP-stimulated Pf. In higher concentrations, TMB-8 inhibits adenylyl cyclase activity directly.  相似文献   
43.
烯丙胺类抗真菌药物比较分子力场分析(CoMFA)的研究   总被引:1,自引:0,他引:1  
本实验采用“活性类似物法”确定了烯丙胺类抗真菌化合物的药效构象,采用比较分子力场分析法(CoMFA)拟合了48个烯丙胺类抗真菌化合物对6种常见致病真菌的3D-QSAR方程,并比较了2种不同叠合规则对模型的影响,最后,用5个新合成化合物对所拟合的抗石膏样毛癣菌、抗烟曲霉菌的CoMFA模型的预测能力进行了检验,得到比较满意的结果。  相似文献   
44.
BACKGROUND: Fresh-frozen plasma (FFP) has generally been regarded as an acellular component. Recently, viable lymphocytes have been detected in this component and the question of irradiation of FFP for certain patients has been raised. Whether the numbers of white cells (WBCs) in FFP are sufficient to require WBC-reduction of acellular components for patients receiving WBC-reduced cellular components has not been determined. WBC numbers in FFP were examined, and the performance of a new commercial WBC-reduction filter for FFP was assessed. STUDY DESIGN AND METHODS: WBC numbers in plasma processed for use as FFP and in thawed FFP were counted before and after WBC-reduction filtration by the use of flow cytometry Fast and slow filtration was used to simulate laboratory and bedside filtration, respectively. Three different methods for plasma harvesting (soft-spin, hard-spin, and second-spin methods) were assessed. The filter capacity was also examined. RESULTS: The numbers of WBCs in plasma covered a three-log10 range (soft-spin method, 0.04-3.6 × 10(6); hard-spin method, 0.47-45.4 × 10(6); second- spin method, 0.4–37.2 × 10(6)). For the hard-spin and second-spin methods which produced the greatest plasma yields, 92 percent and 85.7 percent of bags, respectively, had counts>1 × 10(6) and 43 percent (hard-spin method) and 45.7 percent (second-spin method) had counts>5 × 10(6). There was no significant difference between the counts obtained in plasma and thawed FFP. The filter reduced WBC numbers to <1 × 10(5) in all but 3 of 49 bags. In the remaining three, there were <2 × 10(5) WBCs. Five bags of plasma could be processed effectively through each filter. CONCLUSION: FFP may contain WBC numbers above the threshold at which the use of WBC-reduction filters for cellular components in some patients is necessary. Confirmation of these findings and similar investigations on plasma prepared by other methods may help in defining a role for the use of WBC-reduction filters for FFP  相似文献   
45.
Calcium transport was studied in isolated S2 segments of rabbit superficial proximal convoluted tubules. 45Ca was added to the perfusate for measurement of lumen-to-bath flux (JlbCa), to the bath for bath-to-lumen flux (JblCa), and to both perfusate and bath for net flux (JnetCa). In these studies, the perfusate consisted of an equilibrium solution that was designed to minimize water flux or electrochemical potential differences (PD). Under these conditions, JlbCa (9.1 +/- 1.0 peq/mm X min) was not different from JblCa (7.3 +/- 1.3 peq/mm X min), and JnetCa was not different from zero, which suggests that calcium transport in the superficial proximal convoluted tubule is due primarily to passive transport. The efflux coefficient was 9.5 +/- 1.2 X 10(-5) cm/s, which was not significantly different from the influx coefficient, 7.0 +/- 1.3 X 10(-5) cm/s. When the PD was made positive or negative with use of different perfusates, net calcium absorption or secretion was demonstrated, respectively, which supports a major role for passive transport. These results indicate that in the superficial proximal convoluted tubule of the rabbit, passive driving forces are the major determinants of calcium transport.  相似文献   
46.
Antisickling effects of 2,3-diphosphoglycerate depletion   总被引:2,自引:0,他引:2  
Poillon  WN; Kim  BC; Labotka  RJ; Hicks  CU; Kark  JA 《Blood》1995,85(11):3289-3296
Elevation of 2,3-bisphosphoglycerate (2,3-DPG) in sickle erthrocytes (SS RBCs) and concomitant acidification of the cell interior promote polymerization by decreasing the solubility (csat) of deoxyhemoglobin S. The antisickling effect of 2,3-DPG depletion was evaluated after activation of the 2,3-DPG phosphatase activity of bisphosphoglycerate mutase by glycolate-2-phosphate, leading to rapid loss of intracellular 2,3-DPG. To ensure its maximal reduction in a physiologic medium, isosmotic CO2/bicarbonate-buffered saline, pH 7.0, was used. Substitution of K+ for Na+ as the major extracellular cation suppressed K:Cl cotransport, prevented cell shrinkage, and allowed demonstration of the full antisickling effect of 2,3-DPG depletion. The modest effect on solubility per se of removing intraerythrocytic 2,3-DPG (delta Csat = 1.6 g/dL) was amplified into a much larger antisickling effect by interaction with three other cellular variables affecting solubility and polymer content (intracellular pH, O2 saturation, and mean cell hemoglobin concentration). Acting in concert, these four antisickling effects (three solubilizing, one osmotic) reduced polymer fraction of glycolate-treated SS RBCs by 32% to 63%, with a concomitant decrease in sickling of 46% to 95% at the nominal pO2 of the microcirculation (20 mm Hg). A decrement in sickling of this magnitude should significantly ameliorate the vasoocclusive severity of sickle cell disease.  相似文献   
47.
2-Chloro-2'-deoxyadenosine (CldAdo) and 9-beta-D-arabinosyl-2- fluoroadenine (F-ara-A) have shown marked activity in the treatment of indolent lymphoid malignancies. Based on the susceptibility of various lymphocyte populations to apoptosis, we investigated whether CldAdo or F-ara-A would induce this process in lymphocytes from patients with chronic lymphocytic leukemia (CLL). In vitro exposure of leukemic lymphocytes to CldAdo or F-ara-A for 24 to 72 hours elicited features of apoptosis visible by light and electron microscopy. Analysis of DNA integrity showed DNA cleavage into nucleosomal-sized multimers. Using a quantitative assay, drug-induced DNA fragmentation was both time and dose dependent. Inhibition of active macromolecular synthesis did not prevent drug-induced fragmentation; however, both drug-induced and spontaneous DNA fragmentation were prevented by intracellular calcium chelation. In vitro culture with phorbol ester generally decreased drug- induced DNA cleavage. After prolonged incubation, CLL cells exhibited spontaneous cleavage; albeit, at significantly lower rates than drug- treated cells. Heterogeneity was observed for spontaneous and drug- induced DNA fragmentation and was significantly lower in B-leukemic cells obtained from patients with high-risk and refractory disease. We conclude that CldAdo and F-ara-A are potent inducers of apoptotic death in CLL and that this feature correlates with the disease status.  相似文献   
48.
Soltero L, Carbajal H, Xu J, McCarthy J, Suki WN, Gaber AO, Adrogué HE. Initial survival data of kidney transplant patients with pre‐transplant monoclonal gammopathy.
Clin Transplant 2011 DOI: 10.1111/j.1399‐0012.2011.01539.x.
© 2011 John Wiley & Sons A/S. Abstract: Background: Monoclonal gammopathy of undetermined significance (MGUS) is the presence of a serum monoclonal protein at a concentration of <3 g/dL without evidence of lymphoproliferative disease or organ damage. The prevalence of MGUS in kidney transplantation (KT) candidates is unknown. The present is a retrospective report of patients who underwent evaluation for a KT and were found to have MGUS at our center. Methods: All transplant candidates found to have MGUS between the years 2000 and 2007 were included. Variables were collected. Patients with MGUS that received a KT were compared with patients with MGUS that were not transplanted. Results: Of a total of 1215 KT candidates, 34 were found to have MGUS during the KT evaluation. Nine patients with MGUS were transplanted. Myeloma or lymphoproliferative disease was not observed. Following transplantation, the MGUS group had a lower survival than the non‐transplanted group. However, survival from the time of MGUS diagnosis was not different between the transplanted and non‐transplanted MGUS groups. Conclusions: In this group, transplantation did not confer a survival benefit. It is our hope that these initial data will serve as a platform for future studies. We suggest MGUS screening in all patients older than 50 yr of age undergoing evaluation for transplantation.  相似文献   
49.
Among 67 renal transplant recipients with nephrotic syndrome (NS), nine episodes were reversible in eight patients. Biopsies showed minimal-change disease, focal segmental membranous glomerulonephritis and acute glomerulitis, IgA nephropathy and acute glomerulitis or thrombotic microangiopathy, and chronic transplant nephropathy with or without acute glomerulitis. NS developed 1-4 months post transplant in the four patients with minimal-change disease, but later (33-151 months) in the others. At onset, serum creatinine was normal or elevated. Treatment included calcium-channel blockers, angiotensin-converting enzyme inhibitors, or both, together with routine antirejection therapy. Remission was achieved 4-12 months after onset, when renal function remained normal in four, improved in four, and worsened in one. At last follow-up, six patients still had remission and functional grafts. One lost graft to chronic transplant nephropathy while NS remained in remission. In the remaining patient, proteinuria, which was due to chronic transplant glomerulopathy unrelated to the initial minimal-change disease-associated NS, recurred 50 months post transplant. Remission of post-transplant NS is possible. It is often associated with minimal-change diseases and less frequently with other glomerular lesions, including acute glomerulitis. Reversible post-transplant NS does not have an adverse effect on the renal allografts.  相似文献   
50.
运用Ca2+指示剂Fura-2作为细胞内钙离子的荧光探针,利用AR—CM—MIC阳离子测定系统,检测了分离的神经细胞内游离钙及其变化,并观测了DGAVP和Org2766对蛋白质合成抑制剂茴香霉素(ANI)引起细胞内钙离子浓度([Ca2+]i)变化的影响。结果表明茴香霉素可使[Ca2+]i显著升高,且有量效关系;DGAVP本身并不引起[Ca2+]i发生显著变化,但适当剂量的DGAVP可显著对抗一定剂量范围内ANI升高[Ca2+]i的作用,提示DGAVP对抗ANI的蛋白质合成抑制效应可能是通过拮抗ANI升高[Ca2+]i这一途径实现的,另一神经肽Org2766则可能不是通过这一机制发生作用。从细胞内Ca2+的角度看,这两种肽的作用机理显然是不同的。  相似文献   
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