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991.
We present a summary of the quadrupolar metal ion NMR studies of metalloproteins conducted in our laboratory in recent years. The approaches we employ can be subdivided into two categories: (i) the use of low-frequency metal nuclei to probe metal ion binding sites in small proteins, exemplified by 43Ca NMR studies of alpha-lactalbumins and calcium-binding lysozymes, and (ii) the novel detection of the central transition of half-integer quadrupolar nuclei of moderate frequency bound to large metalloproteins, typified by 27Al, 45Sc, 69,71Ga, and 51V NMR studies of the transferrins. We highlight the chemical information regarding the nature of metal ion binding sites that can be obtained from this technique and emphasize the salient parameters that an investigator must consider to successfully apply quadrupolar NMR to the study of biological macromolecules. 相似文献
992.
D Mesa Rubio M Franco Zapata M Anguita Sánchez A Ramírez JM Arizón del Prado J Suarez de Lezo F Vallés Belsué 《Canadian Metallurgical Quarterly》1998,51(8):680-683
The pulmonary thromboembolism is a frequent and severe disease, usually difficult to recognize, specially in patients with thrombotic material trapped within right heart cavities. We present our experience in three patients with severe pulmonary thromboembolism where echocardiographic study demonstrated the presence of huge mobile thrombus in right heart cavities, which demanded urgent therapy with excellent results. We would like to stress that echocardiographic study in these patients could be elective diagnostic procedure, avoiding the realization of pulmonary arteriography, which could bring risk of possible thrombus mobilization. 相似文献
993.
RG Khadaroo JM Walton JA Ramsay MJ Hicks SD Archibald 《Canadian Metallurgical Quarterly》1998,33(6):893-895
Although mucoepidermoid carcinoma (MEC) is the most common malignant salivary gland neoplasm in childhood and adolescence, it is rarely found in children under the age of 10. A 6-year-old girl had an asymptomatic neck mass for 5 months. Clinical examination findings showed a 1.5-cm smooth and firm but mobile nontender mass located in the upper left anterior cervical triangle, clinically separate from the parotid gland. Ultrasound examination findings showed a vascular mass, with a cystic component, possibly within the tail of the parotid gland. An excisional biopsy was performed and frozen section showed a low-grade MEC. A left superficial parotidectomy was then performed. Final histopathologic examination showed one positive resection margin. Subsequently, reexcision of the surgical site and an upper modified neck dissection was undertaken. This unusual presentation of MEC as a neck mass in one of the youngest reported patients illustrates that the anatomic region for parotid tumors is large. Possibly some of these tumors may arise from heterotopic or accessory parotid tissue. 相似文献
994.
H Djouhri L Arrivé L Monnier-Cholley M Baud H Dahan JM Tubiana 《Canadian Metallurgical Quarterly》1998,79(9):889-891
OBJECTIVE: To report a suspected case of isoniazid-induced psychosis in a 31-year-old woman. CASE SUMMARY: A 31-year-old white woman without a prior psychiatric history presented with psychotic symptoms suspected to be related to prophylactic treatment with isoniazid after she tested positive to a tuberculin (purified protein derivative) test. The psychotic symptoms resolved partially after isoniazid was discontinued and completely after treatment with olanzapine was begun. The patient remained symptom-free 11 months after discharge from the hospital. DISCUSSION: Cases of isoniazid-related psychiatric disorders reported in the literature include psychosis, obsessive-compulsive neurosis, and mania. With the increasing prevalence of tuberculosis in the US, more people are expected to receive treatment for tuberculosis. Pyridoxine deficiency may play a role in the pathogenesis of isoniazid-induced psychosis. Such deficiency states may be detected indirectly by measuring urinary metabolites of tryptophan. CONCLUSIONS: Clinicians should be aware of this adverse effect of isoniazid and that it may present with a broad clinical picture. 相似文献
995.
A survey of indications and results of cryopreserved testicular spermatozoa has been performed by French Federation of CECOS from 1 January 96 to 31 December 97. 340 sperm cryopreservations (264 with testicular sperm) has been performed: 252 in excretory azoospermia, 88 in non obstructive azoospermia. 30 cycles of ICSI was performed with frozen-thawed spermatozoa with 6 clinical pregnancies (20%). 相似文献
996.
V Segarra MI Crespo F Pujol J Beleta T Doménech M Miralpeix JM Palacios A Castro A Martinez 《Canadian Metallurgical Quarterly》1998,8(5):505-510
In order to define more precisely the risk of hypoglycaemia in GH-deficient children and to clarify the role of growth hormone (GH) in glucose homeostasis, a 24-h fast was monitored in 10 GH-deficient children aged 1.1-6.5 y. Asymptomatic hypoglycaemia (blood glucose < or = 2.6 mmol/l) occurred in 9/10 children, 2 of whom prematurely interrupted the test. Blood glucose profile was not reproducible between children and had no correlation with age (p = 0.48). Gluconeogenesis was considered as non-altered as read from the normal plasma lactate and pyruvate concentrations throughout the test. Plasma ketone body concentrations increased during the test, but were lower than expected with respect to the decrease of blood glucose. This suggests insufficient ketogenesis which could exacerbate hypoglycaemia in GH-deficient children if brain glucose utilization were not alleviated by ketone body oxidization, as is normally the case. The positive glucose response after glucagon stimulation in 6/10 patients indicated normal hepatic glycogen content. However, these responses were unexpected following the prolonged fast and its concomitant hypoglycaemia, and would therefore tend to suggest a defect in glycogenolysis. These results confirm the tendency to hypoglycaemia, even after infancy, in GH-deficient children. These hypoglycaemias may occur by different types of malfunctioning, such as insufficient ketogenesis or a defect in glycogenolysis. These hypotheses require confirmation by a more systematic study of the metabolic and hormonal changes that occur during fasting in both GH-deficient and normal children. 相似文献
997.
AD Dwarakanath LG Yu C Brookes D Pryce JM Rhodes 《Canadian Metallurgical Quarterly》1995,37(4):585-588
Pyoderma gangrenosum is strongly associated with inflammatory bowel disease and exhibits pathergy, occurring at sites of previous minor trauma. A patient is presented with a 21 year history of extensive ulcerative colitis, who developed pyoderma gangrenosum and arthralgia while receiving high dose corticosteroids for active ulcerative colitis. The arthralgia exhibited pathergy affecting particularly the left temporomandibular joint, which was stressed by an asymmetric bite, and the left elbow, which had been fractured many years previously. This prompted the hypothesis that neutrophils in this condition may be marginated, as a result of increased stickiness of either the neutrophil or the vascular endothelium. The introduction of heparin therapy was associated with rapid resolution of the arthralgia, pyoderma gangrenosum, and ulcerative colitis. 相似文献
998.
999.
An NSF-like ATPase, p97, and NSF mediate cisternal regrowth from mitotic Golgi fragments 总被引:2,自引:0,他引:2
Golgi cisternae regrew in a cell-free system from mitotic Golgi fragments incubated with buffer alone. Pretreatment with NEM or salt washing inhibited regrowth, but this could be restored either by p97, an NSF-like ATPase, or by NSF together with SNAPs and p115, a vesicle docking protein. The morphology of cisternae regrown with p97 and NSF-SNAPs-p115 differed, suggesting that they play distinct roles in rebuilding Golgi cisternae after mitosis. 相似文献
1000.
Radiotherapy-induced emesis depends on the site of irradiation, the field size and the dose per fraction and is generally less intense than chemotherapy-induced emesis. Established anti-emetic drugs offer only limited symptom control (50%). Ondansetron, a 5HT3 receptors antagonist, had proven a complete or a major control efficacy (0-2 emetic episodes) of 68 to 95% in three pilot studies (fractionated, single-dose and total body irradiations). In controlled studies, ondansetron efficacy was significantly higher than placebo, metoclopramide and prochlorperazine. The treatment was well tolerated in the different studies. 相似文献