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排序方式: 共有9696条查询结果,搜索用时 15 毫秒
1.
Facilitated uptake of zinc into human erythrocytes. Relevance to the treatment of sickle-cell anaemia 总被引:1,自引:0,他引:1
R C Hider L Ejim P D Taylor R Gale E Huehns J B Porter 《Biochemical pharmacology》1990,39(6):1005-1012
The ability of a number of heterocyclic metal chelators to deliver zinc into red cells, to release the liganded zinc to haemoglobin and thereby cause a left shift in the oxygen dissociation curve of intact red cells has been investigated. Incubation of neutrally charged zinc-pyrone and zinc-pyridin-2-one complexes with red cells led to the rapid accumulation of zinc within cells, whereas unliganded zinc in the form of zinc acetate, zinc chloride or zinc sulphate accumulated only slowly. The rate at which zinc was delivered to red cells by pyrone and pyridin-2-one ligands increased with increasing lipid solubility of the ligands. The uptake of zinc into both normal adult and sickle red cells was associated with a dose-dependent increase in the oxygen affinity of haemoglobin. The degree of left shift in the oxygen dissociation curve following the incubation of red cells with zinc-pyrone and -pyridin-2-one complexes suggests that these complexes may find application as agents to increase the oxygen affinity of haemoglobin in sickle cell disease and thereby decrease the probability of intravascular sickling at low tissue oxygen tensions. Ethylmaltol appears to be a particularly useful agent due to its known low toxicity. 相似文献
2.
T E Porter B M Hargis J L Silsby M E el Halawani 《General and comparative endocrinology》1989,74(3):400-405
This study was conducted to determine if lower steroid secretion by the small white follicles in incubating turkey hens contributes to lower circulating steroid concentrations during this time. Turkey hens were grouped as either laying or incubating. Serum samples and the ovarian small white follicles (SWF; 2-7 mm diameter) were collected from each hen. The SWF were pooled for each group and their cells were dispersed by trypsin digestion. Serum-luteinizing hormone (LH), progesterone (P), testosterone (T), and estradiol (E) concentrations were lower and serum prolactin concentration was higher during incubation than during egg laying. SWF cells from incubating hens secreted more P and T and less E in response to ovine luteinizing hormone (oLH) than did similar cell suspensions from laying hens. The incubating hens' SWF cells' capacity to secrete E but not their capacity to secrete P or T in vitro is consistent with the observed circulating levels. It is hypothesized that lower levels of circulating LH and/or higher levels of prolactin found in incubating hens may have a depressing effect on aromatase activity and/or an up-regulating effect on LH-induced P and T secretion by the SWF cells. 相似文献
3.
Eric T. Stoopler DMD res Pinto DMD Faizan Alawi DDS Sree Raghavendra DMD Ricardo Boyce Jr. DDS David Porter MD Thomas P. Sollecito DMD 《Special care in dentistry》2004,24(2):65-69
Acute myelogenous leukemia (AMU is a hematologic disorder that is characterized by an abnormal proliferation of immature myeloid cells. Granulocytic sarcomas are clusters of leukemic myeloid cells that may develop as a result of AML. Oral manifestations of AML are common and often involve enlargements of the gingiva and/or mucosal tissue from direct leukemia cell infiltration. We describe the case history of a 50-year-old man who had an ulcera-tive lesion of the oral mucosa that was determined to be a granulocytic sarcoma of AML-M0 subtype. The combination of both the subtype and clinical presentation of the leukemia makes this presentation unusual, and to the best of our knowledge, of a type that has not been previously reported in the literature. 相似文献
4.
ROLF HULTCRANTZ BO ANGELIN KURT EINARSSON LEIF FRIMAN 《Journal of internal medicine》1987,221(5):503-507
ABSTRACT. Hultcrantz R, Angelin B, Einarsson K, Friman L (Departments of Internal Medicine and Roentgenology, Serafimer Hospital, and Department of Internal Medicine, Huddinge University Hospital, Karolinska Institute, Stockholm, Sweden). Spontaneous regression of Budd-Chiari syndrome (hepatic venous occlusion) in a young female. Acta Med Scand 1987; 221:503–7. A case of occlusion of the hepatic veins in an 18-year-old girl is presented. The onset was sudden with massive ascites and markedly impaired general condition. The diagnosis was based on liver biopsy and angiograms of the caval and hepatic veins as well as of the celiac artery. No predisposing factors could be found. The patient was treated conservatively with laparo-centesis and diuretics. Clear improvement was seen after two weeks, and after four weeks she had no ascites and could be discharged. All liver function tests were then normalized. After three months, all diuretics could be withdrawn, and in the following 11 years she has remained completely recovered. The case illustrates that also widespread thrombi of the hepatic veins may sometimes rapidly dissolve spontaneously, with apparent total reconstitution of hepatic function. This case is unusual since previously reported cases have had high mortality rates and, in surviving cases, operative procedures or large doses of diuretics have been required to control the ascites. 相似文献
5.
6.
SUNG-GOO CHANG CHUL-SOO KIM SEUNG HYUN JEON YOUN-WHA KIM BO YOUL CHOI 《International journal of urology》2006,13(2):122-126
AIM: To evaluate the cause of elevated prostate-specific antigen (PSA) in patients with transrectal needle biopsy negative for prostate cancer. METHODS: Serum PSA concentration, prostate volume, and pathologic findings were examined in 223 patients with negative biopsy for prostate cancer. The degree of prostate inflammation was determined by the extent and degree of inflammation shown by biopsy specimens and is expressed as an inflammation score (range: 0-36). RESULTS: A significant correlation was found between PSA concentration and prostate total volume (P=0.0001). Prostate chronic inflammation showed no correlation with PSA concentration (P=0.485, F=0.488). After allocating patients to normal PSA (4 ng/mL) groups, we found that serum PSA concentrations in both groups were predominantly affected by prostate total volume. CONCLUSIONS: An increase in prostate volume appears to be the major contributor to a high serum PSA concentration in patients with negative biopsy for prostate cancer. However, in contrast to previous reports, there was no correlation between the degree of prostate chronic inflammation and serum PSA concentrations. 相似文献
7.
To identify and compare the methods of evaluation for suspected traumatic aortic rupture, 1,031 trauma charts from 1983-1989 were reviewed. Fifty-nine patients were evaluated for possible aortic injury. Patients who died before completion of the CT or aortogram were excluded. Widening of the mediastinum on chest x ray was the most frequent indication for follow-up studies. Twenty-five had a CT of the aortic arch alone. No study showed disruption. There were no false negative studies. Thirty patients had only aortography. Twenty-four were read as normal (one false negative). Six were read as positive (one false positive). In four, both studies were performed (CT/aortography--TP/TP, TN/TN, TP/FN, FP/FP). (FP = False Positive, TP = True Positive, FN = False Negative, TN = True Negative.) Six received surgical repair of the aortic injury (one death). In this experience, CT was used successfully as a screening tool for aortic disruption. It was highly sensitive in recognizing aortic injuries when present (100% vs. 75% for aortography) and in most cases did not require aortographic verification. False positive rates were comparable (CT = 3.8%, aortography = 7.7%). Specificity was also comparable (CT = 96%, aortography = 92%). Overall, four aortograms were inaccurate while only one CT was inaccurate. We recommend the use of CT for the evaluation of widened mediastinum in the stable patient. 相似文献
8.
Poverty, health services, and health status in rural America 总被引:5,自引:0,他引:5
Access to health services for everyone has been a major policy goal in the United States: inequitable access is assumed to lead to inequitable health status, particularly for low-income groups. A sophisticated model of the relation between poverty, health care needs, service use, and health outcomes is used to analyze cross-sectional data on 7,823 adults from 36 rural communities. Improved access and use are helpful, but evidence clearly indicates that combined health and social initiatives will be necessary to reduce inequalities in health status. 相似文献
9.
NATURE AND HEALING OF TIBIAL SHAFT FRACTURES IN ALCOHOL ABUSERS 总被引:3,自引:1,他引:2
NYQUIST FREDRIK; BERGLUND MATS; NILSSON BO E.; OBRANT KARL J. 《Alcohol and alcoholism (Oxford, Oxfordshire)》1997,32(1):91-95
Alcohol abuse is associated with an increased risk of osteopeniaand fractures. Previous histomorphometric studies on iliac crestbone have found decreased bone formation and increased boneresorption in alcohol abusers but it has not been establishedwhether alcohol abuse has any effect on the anatomical locationor the healing time of tibial shaft fractures. We studied, retrospectively,199 adult male patients hospitalized for isolated tibial shaftfracture in the city of Malmö, Sweden, between 1980 and1990. Forty-nine of the patients had earlier been registeredat the Department of Alcohol Diseases and were judged to beproblem drinkers. Abusers sustained their tibial shaft fracturesmore often by falling at ground level (P<0.0001) or froma higher level (P=0.009) and the fractures were more often obliquethan transverse (P=0.002) as compared with non-abusers. Healingtime was impaired in abusers who had sustained a transversefracture (P=0.035), but no difference was observed in healingtime in those with an oblique fracture. We found no differencebetween the abusers and the non-abusers regarding duration ofhospital stay, fracture location, amount of displacement, occurrenceof open fractures or the rate of complications. 相似文献
10.
J Porter A Ahsan D Mulcahy U Sigwart 《British journal of hospital medicine》1992,47(6):411, 414, 417-411, 414, 419
In this article we review the early history of the coronary artery stent in clinical cardiology, cite a clinical case and assess the potential role of stents in revascularization in the future. 相似文献