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121.
A health study was carried out on 2066 workers in an aluminum smelter in Kitimat, British Columbia to study the effects of exposure to fluoride and other air contaminants encountered on the potlines on the musculoskeletal system, hemopoietic tissue, liver, and renal function. Three hundred seventy-two railway repair workers from Squamish, British Columbia served as an "external" control group. Examination of the spine and sacroiliac joints and pelvic X-ray were conducted on long-term potline workers and a number of "internal" control workers in the smelter not exposed to any air contaminants. Urinary fluoride measurements and personal sampling for airborne fluoride were also carried out. Blood samples were collected for routine blood count and liver and renal function test. Definite cases of skeletal fluorosis were not found in any potroom workers. Some of the changes of early skeletal fluorosis described on pelvic X-rays, e.g., increased density, calcification of ligaments, and periosteal changes, were found in a few workers who were employed on the potlines for more than 10 yr. There was, however, poor agreement in the findings of the two radiologists who read the films. The entity "musculoskeletal fluorosis" does not exist in this smelter where the potroom workers were exposed to total fluoride levels below the currently accepted threshold limit value of 2.5 mg/m3. No ill effects on the hematopoietic tissue or liver and renal function were found.  相似文献   
122.
Eudesmanolides and Other Constituents from Artemisia argyi   总被引:10,自引:0,他引:10  
Tan R  Jia Z 《Planta medica》1992,58(4):370-372
The phytochemical investigation of the aerial parts of ARTEMISIA ARGYI afforded beta-sitosterol, stigmasterol, alpha-amyrin, beta-amyrin, friedelin, naringenin, quercetin, and four eudesmane derivatives, two of which were new eudesmanolides. The structures of the novel compounds were elucidated by high field NMR techniques.  相似文献   
123.
An ischemic myocardial region contains cells with a depolarized resting membrane potential. This depolarization leads to an intercellular current flow between the ischemic region and the surrounding normal myocardial cells, which has been termed an "injury current." We have devised an experimental model system in which an isolated rabbit ventricular cell is electrically coupled to a model depolarized cell to evaluate the effects of this injury current on the electrical properties of a normal ventricular cell. We found that the action potential duration of the isolated cell could be reversibly altered by varying the coupling resistance such that the action potential duration was shortened by high values of coupling resistance but could be considerably prolonged by lower resistance coupling. We did not observe automaticity in the isolated cell as a consequence of coupling to the depolarized model. The changes in action potential duration were accompanied by alterations in the frequency at which the isolated cell could respond to repetitive stimuli. In addition, the depolarization of the isolated cell produced by the electrical coupling led to a significant increase in the cellular excitability. This last effect may be of particular importance in understanding the mechanisms for origination of arrhythmias in the border zone of myocardial ischemia.  相似文献   
124.
Clinical characteristics of pramipexole-induced peripheral edema   总被引:4,自引:0,他引:4  
BACKGROUND: Pramipexole, a new dopamine agonist, effectively treats early and advanced Parkinson disease and restless legs syndrome. OBJECTIVES: To report the clinical features of and to investigate the predisposing factors and eventual outcomes in patients who developed peripheral edema (PE) following treatment with pramipexole. DESIGN: Retrospective case series in a tertiary referral center. RESULTS: Of the 300 patients who were receiving pramipexole therapy, 17 patients had mild to severe PE, which was attributable to the medication. Fifteen patients had Parkinson disease and 2 patients had restless legs syndrome. The mean (+/-SD) time of onset of PE after pramipexole therapy was started was 2.6 +/- 3.6 months (range, 0.25-11 months). The mean (+/-SD) dose at onset of PE was 1.7 +/- 1.0 mg/d (dose range, 0.75-3 mg/d) and the mean (+/-SD) dose when PE was at its maximum was 2.6 +/- 0.7 mg/d (dose range, 1.5-3 mg/d). In all cases, the PE rapidly abated with discontinuation of therapy, and in all cases that we rechallenged, it rapidly returned. The condition seemed to be dose dependent but also idiosyncratic, as we could not identify any predisposing features. It resulted in extensive medical evaluation in some patients and was only minimally responsive to diuretic therapy. CONCLUSION: Peripheral edema should be included among the potential adverse events associated with pramipexole therapy.  相似文献   
125.
HPLC法测定冠心通络片中橙皮苷的含量   总被引:1,自引:0,他引:1  
目的:建立冠心通络片中橙皮苷含量的测定方法。方法:采用高效液相色谱法,色谱柱为HypersilODSC18(5μm,4.6mm×100mm);流动相为甲醇-5%醋酸溶液(30∶70);检测波长为283nm;柱温为30℃;流速为1.0mL/min。结果:橙皮苷在419.2~2096μg(r=0.9998,n=5)范围内呈良好的线性关系;平均回收率98.71%;RSD为1.13%。结论:本法检测快速,定量准确,可用于冠心通络片的定量分析。  相似文献   
126.
瘤内注射重组人p53腺病毒治疗晚期肺癌临床试验观察   总被引:1,自引:0,他引:1  
目的 观察重组人p53腺病毒注射液(rAd-p53)在晚期肺癌治疗中的疗效和毒副反应。方法 12例IIIb-IV期肺癌及3例肺转移癌,CT定位经皮肺穿刺瘤内注射rAd-p53,1 次/周×4/疗程;通过临床观察、CT及病理对照及短期随访进行评价。结果 治疗后2 月观察肿瘤缩小5例(33.3%),无变化7例(46.7%),增大3例(20%);治疗后病理观察:癌组织坏死,癌细胞稀少(6/11,54.5%);除自限性发热外,无明显毒副反应。结论rAd-p53瘤内注射治疗肺癌,无明显毒副作用,能较好地抑制局部肿瘤的发展,尤其对失去手术机会,不能耐受放化疗的患者,是一种可行的有前景的方法。  相似文献   
127.
The Bcl-2 oncoprotein is commonly overexpressed in hematological malignancy, where it promotes the survival of neoplastic cells. Recently, a small molecule (HA14-1) was reported to bind the surface pocket of Bcl-2 that mediates antiapoptotic interactions, triggering apoptosis in a Bcl-2-transfected cell line. We investigated the activity of this compound in a panel of malignant hematopoietic cell lines. Consistent with its proposed role as a Bcl-2 inhibitor, HA14-1 was most cytotoxic in lines expressing high levels of Bcl-2. In addition, at lower concentrations (5-12.5 muM), the compound predominantly triggered apoptosis. However, at concentrations two-fold higher than this and above, increasing primary necrosis was observed, suggesting the onset of interactions supplementary to Bcl-2 inhibition. In experiments on primary cells, 25 muM HA14-1 induced extensive apoptosis in acute leukemic blasts, but also suppressed normal hematopoietic colony formation to <50% of baseline. Importantly, low-concentration HA14-1 (5 muM) was nontoxic to normal colony-forming cells, whereas it enhanced the cytotoxicity of the antileukemia drug cytarabine in Bcl-2-positive lymphoblastic leukemia cells. In conclusion, our results indicate that HA14-1 at low concentration selectively triggers apoptosis in malignant hematopoietic cells that overexpress Bcl-2. Agents of this class may have particular utility in combination with cytotoxic chemotherapy drugs.  相似文献   
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Rosai-Dorfman disease, also known as sinus histiocytosis with massive lymphadenopathy, is a rare but distinct clinicopathologic entity characterised histologically by a benign s histiocytic proliferation. Isolated involvement of extranodal sites without concomitant nodal disease is rare. We describe the pathological features of 2 cases of Rosai-Dorfman disease that were clinically confined to the skin. In both male adult Chinese patients, proliferation of histiocytes was accompanied by S-100 protein expression demonstrated immunohistochemically within the histiocytes. The pathology of Rosai-Dorfman disease and its microscopic differential diagnoses are discussed.  相似文献   
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