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11.
Abstract: The effects of zinc on the production of active oxygen species were investigated in rat neutrophils by chemilumi-nescence and spectrophotometric assays. The luminol-dependent chemiluminescence in unstimulated neutrophils showed a single peak. Zinc at concentrations lower than 0.1 mM augmented the intensity of chemiluminescence and showed a bimodal pattern, the first peak of which was inhibited by superoxide dismutase and catalase, while the second peak disappeared in the presence of catalase, but was unaffected by superoxide dismutase. At the same concentrations of zinc, O2? and H2O2 production increased, but secretion and activity of myeloperoxidase were not affected. Zinc at 0.1 mM enhanced the second peak of luminol-dependent chemiluminescence, and concomitantly O2? and H2O2 production of neutrophils stimulated with formyl-methionyl-leucyl-phenylalanine. Homogenized neutrophils showed a bimodal pattern on induction by zinc, the second peak of which was inhibited slightly by catalase and completely by sodium azide, but was not inhibited by superoxide dismutase. Zinc-induced O2? production was inhibited by pertussis toxin, but was not significantly inhibited by a protein kinase C inhibitor, 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H-7), or a calmodulin antagonist, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7). These results suggest that zinc can augment luminol-dependent chemiluminescence by increasing O2? production through the classical signal transduction pathway, and by increasing H2O2 not via O2?.  相似文献   
12.
13.
In five of six cases of camptodactyly in which an abnormality of the flexor tendon was examined at operation, the flexor digitorum superficialis tendon was hypoplastic and there was no continuity of the normal tendon between the muscle belly and bony insertion. The proximal end of the flexor digitorum superficialis tendon was attached to the palmar aponeurosis and the flexor tendon sheath of the ring finger in two patients, to the palmar aponeurosis in one, to the undersurface of the transverse carpal ligament in one and to the flexor tendon sheath of the ring finger in one. The tenodesis effect of the abnormal tendon of the flexor digitorum superficialis is considered to play an important role in the cause and rapid increase of the deformity of camptodactyly.  相似文献   
14.
We report the surgical results of 13 accessory nerve neurotizations in brachial plexus birth palsy. The mean age at operation was 5.9 months. The accessory nerve was transferred to three C5 roots, to three C6 roots, to four posterior division of the middle trunks, to one musculocutaneous nerve, and to two suprascapular nerves. Sixty-seven percent of the cases acquired M4 or more in the deltoid muscle, 88% in the infraspinatus muscle, and 100% in the biceps brachii muscle. Twenty-five percent of the cases acquired M4 or more in the triceps brachii muscle and the wrist extensor muscles. These results were much better than formerly reported for adult cases by other authors. No functional compromise of the trapezius muscle was noted. The accessory nerve neurotization can be used safely and effectively in neurosurgical reconstruction of the brachial plexus palsy in infants. © 1994 Wiley-Liss, Inc.  相似文献   
15.
We did 18 arthrodeses of the wrist in 16 patients with rheumatoid arthritis using an intramedullary fixation technique. There were 15 women and one man, whose ages at operation ranged from 47 to 71 years (mean 58). Follow up ranged from 13 to 68 months (mean 27). The operative technique consists of a combination of intramedullary placement of two Kirschner (K)-wires and an autogenous bone graft. At follow up bony union was apparent in all cases. K-wires came out of the metacarpal joints in two cases. Paraesthesiae in the median nerve distribution occurred in two cases which both recovered within three months.  相似文献   
16.
We describe the case of a 61-year-old woman diagnosed with primary Sj?gren's syndrome (SS) after an 8-year history of IgA nephropathy and a 3-year history of recurrent purpuric rashes. Her two daughters had previously been diagnosed with other autoimmune diseases. One daughter had Graves' disease and the other had Hashimoto's disease and systemic lupus erythematosus. The diagnosis of SS was made based on dryness of mucous membranes, Shirmer test, and parotid sialography. Thrombocytopenia, high platelet-aggregated IgG (PA-IgG) level, and normal megakaryocytes count in bone marrow suggested that her recurrent purpuric rashes were due to idiopathic thrombocytopenic purpura (ITP). Patients with SS may develop other autoimmune diseases. This case aids understanding of the immune pathogenesis and genetic background of SS.  相似文献   
17.
Late Effects of Childhood Acute Leukemia and Its Treatment   总被引:1,自引:0,他引:1  
Late effects of childhood acute leukemia and its treatment were studied in 766 patients (684 ALL, 73 ANLL, and 9 others) in Japan who had remained in remission for more than 1 year after their first complete remission. Delayed adverse sequelae involve a wide variety of organs and their functions. Short stature was present in 2.61%, obesity in 3.79%, abnormalities of growth hormone secretion in 1.5%, delayed secondary sex characteristics in 1.5% of males and 0.6% of females, motor disturbances in 1.17%, sensory disturbances in 0.91%, intellectual and learning disabilities in 2.48%, abnormal findings in routine neurologic examinations in 1.31%, EEG abnormalities in 4.30%, brain CT abnormalities in 5.09% and cardiac dysfunction in 1.07%. Various other disorders were seen in 20 patients. Many of these delayed adverse sequelae are caused by or related to central nervous system prophylaxis and systemic combination chemotherapy. The results suggest that it is needed to improve therapeutic methods through the stratification of patients by risk factors and detailed analysis of prognostic factors. Moreover it is important to render medical and psychosocial support to long-term survivors of childhood leukemia through interactions between the patient, parents and medical staff.  相似文献   
18.
The effects of pulsatile cardiopulmonary bypass on the renin-angiotensin-aldosterone system and tissue metabolism, especially those which occur soon after surgery, were studied in 26 patients who required total cardiopulmonary bypass for longer than 60 minutes. These patients comprised 11 who underwent open heart surgery utilizing nonpulsatile cardiopulmonary bypass (Group I) and 15 who underwent open heart surgery utilizing pulsatile cardiopulmonary bypass (Group II). Plasma angiotensin II and serum aldosterene levels were significantly increased one and 5 hours postoperatively in Group I when compared with the preoperative values, whereas no significant elevations were observed in Group II. Plasma angiotensin II and serum aldosterone levels one hour postoperatively in Group II were significantly lower than those in Group I. Lactate levels in the arterial blood were significantly elevated, one and 5 hours postoperatively in both Groups I and II. Moreover, no significant difference was observed in the lactate levels between Groups I and II, one hour postoperatively. In the nonpulsatile group (Group I), plasma angiotensin II levels one hour postoperatively were correlated significantly with the duration of total cardiopulmonary bypass. In conclusion, pulsatile cardiopulmonary bypass offers significant advantages in terms of lower plasma angiotensin II and serum aldosterone levels, when compared with nonpulsatile cardiopulmonary bypass soon after open heart surgery requiring total cardiopulmonary bypass for longer than 60 minutes, however, it does not offer a definite advantage for tissue metabolism.  相似文献   
19.
We examined the effects of angiotensin II (Ang II) on inward rectifier K+ currents (IK1) in rat atrial myocytes. [125I]Ang II-binding assays revealed the presence of both Ang II type 1 (AT1) and type 2 (AT2) receptors in atrial membrane preparations. Ang II inhibited IK1 in isolated atrial myocytes with an IC50 of 46 nmol/l. This inhibition was abolished by the AT, antagonist RNH6270 but not at all by the AT2 antagonist PD123319. Treatment of cells with pertussis toxin or a synthetic decapeptide corresponding to the carboxyl-terminus of Gialpha-3 abolished the inhibition by Ang II, indicating the role of a Gi-dependent signaling pathway. Accordingly, Ang II failed to inhibit IK1 in the presence of forskolin, dibutyryl-cAMP or protein kinase A catalytic subunits. In spite of the increased binding capacities for [125I]Ang II, Ang II failed to affect IKI in cells from spontaneously hypertensive rats (SHR). AT, immunoprecipitation from atrial extracts revealed decreased amounts of Gialpha-2 and Gialpha-3 proteins associated with this receptor in SHR as compared with controls. The reduced coupling of AT, with Gialpha. proteins may underlie the unresponsiveness of atrial IK1 to Ang II in SHR cells.  相似文献   
20.
Kampo, a Japanese-Chinese traditional herbal medicine, has been used for the treatment of various diseases for about 3,000 years in China. Among herbal medicines, Sairei-to is well known for improving the symptoms of rheumatoid arthritis (RA) and other collagen diseases. However, its immunosuppressive effects on autoimmune cutaneous phenomena are not completely understood. We investigated the effects of Sairei-to on the development of lupus dermatoses in autoimmune-prone MRL/Mp-lpr/lpr (MRL/lpr) mice, an animal model which spontaneously develops skin lesions similar to those seen in human lupus erythematosus. Virgin female MRL/lpr mice at 1 month of age, which were treated orally with Sairei-to, had reduced amounts of IgG deposition at the dermoepidermal junction, titers of anti-DNA antibodies and rheumatoid factor, and lymphoproliferation. These results support the use of traditional herbal medicines in patients with human RA and systemic lupus erythematosus.  相似文献   
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