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1.
Balloon dacryocystoplasty: indications and contraindications   总被引:3,自引:0,他引:3  
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Severe bleeding resulting from excessive fibrinolysis has been observed in patients with primary amyloidosis. The authors studied a patient with this hemostatic disorder before and during therapy with epsilon-aminocaproic acid. Excessive fibrinolysis was associated with depressed plasma concentrations of coagulation Factors XII, XI, high-molecular-weight kininogen, and Factors VIII and V; and plasminogen and alpha-2-plasmin inhibitor. These deficiencies were corrected with treatment. The functional and antigenic concentrations of tissue plasminogen activator and plasminogen activator inhibitor in the patient's plasma were normal. Urokinase-type activator activity and antigen were three to five times elevated in the patient's plasma. Results of immunoprecipitation showed that single-chain urokinase-type activator was the primary urokinase-type activator species in the patient's plasma. Excessive fibrinolysis in patients with amyloidosis results from increased plasma single-chain urokinase-type activator activity.  相似文献   
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Respiration and the ECG: a study using body surface potential maps   总被引:2,自引:0,他引:2  
Body surface potential maps and an eccentric spheres model of the heart were used to investigate some of the factors that cause the surface ECG to change with respiration. Although the pattern of the surface maps shifted inferiorly with inspiration, the pattern itself did not change significantly, even with deep respiratory movements. However, the temporal ECGs at specific electrodes changed dramatically. The model simulations show that the contribution to the change in amplitude of the surface potential due to lung conductivity and ventricular volume changes is small. It is suggested that the major cause of the surface potential changes with inspiration is due to the change in heart position.  相似文献   
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The molecular mechanisms involved in luteolysis are still unclear in the primate. This study aimed to investigate the effect of induced luteolysis on the ovarian luteinizing hormone (LH) receptor and the steroidogenic enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset monkey. Luteolysis was induced in the mid-luteal phase either directly by systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal using systemic gonadotrophin releasing hormone antagonist (GnRHant) treatment. The LH receptor was studied by isotopic mRNA in-situ hybridization and in-situ ligand binding and 3beta-HSD expression was studied using isotopic mRNA in-situ hybridization and immunohistochemistry. Induced luteolysis was associated with a reduction in the expression of LH receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a reduction in the LH receptor (P < 0.05) and 3beta-HSD protein concentrations within 24 h. There were no differences in the findings whether luteolysis was induced with PGF2alpha or GnRHant. This study shows that disparate mechanisms to induce luteolysis in the primate result in an identical rapid loss of the LH receptor and 3beta-HSD. In conclusion, induced luteolysis leads to rapid loss of the steroidogenic pathway in luteal cells.   相似文献   
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Immunostaining for pepsinogen with an immunoglobulin-peroxidase bridge procedure has been undertaken in conjunction with cytochemical staining for complex carbohydrate to investigate the composition and nature of large inclusions in gastric chief cells of beige mice with an analog of the human Chediak-Higashi syndrome (CHS). By these methods to stain chief cells and immunostaining for carbonic anhydrase to distinguish parietal cells, stomachs of the beige mouse were compared with those of normal black mice from which the genetic defect arose. The staining has confirmed that the chief cells are involved in CHS and has affirmed that one type of megabody in CHS chief cells contains both group I and group II pepsinogens and apparently arises in a process akin to crinophagy.  相似文献   
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We evaluated 14 patients with bilateral testicular tumour, one-sided tumour and contralateral carcinoma in situ (CIS) of the testis or testis tumour in single testis with respect to their fertility. We analysed semen parameters, serum hormones [follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone], testicular sonography, testicular volumes and testicular histology prior to further anti-cancer treatment. Ten out of 14 patients showed normal or reduced sperm concentrations, while 4/14 patients were azoospermic. Serum FSH levels showed a significant negative correlation with sperm concentrations in patients with testicular malignancies (r = -0.64, P = 0.025). Testicular volumes revealed a significant positive correlation with semen parameters in patients with testes that were affected by CIS (r = 0.733, P = 0.038). We conclude that even bilateral testicular cancer and/or CIS do not preclude fertility and, therefore, patients should be offered andrological investigation and therapy, including possibly surveillance strategy or the chance for cryopreservation of the semen prior to further treatment in order to preserve their chances for paternity.   相似文献   
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