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991.
Experiences with the methods are summarized. Follicular growth was monitored by ultrasound folliculometry (USFM) and estimation of serum estradiol (E2 values in physiologic cycles. USFM was found to predict follicular rupture-ovulation--more precisely than E2 values. Cases of disturbed folliculogenesis (persisting and luteinized unruptured follicle, cysts) are described. The wider use of USFM in Hungary is urged, because appropriate equipment is available while the chances of continuous hormonal monitoring are rather limited. 相似文献
992.
Intraoperative echography is a new field of application of the ultrasound diagnostics. With a special intraoperative examination head the parenchymal abdominal organs may be examined directly in the course of the operation. The intraoperative echo-examination of the tumors and cysts of the liver and pancreas as well as of nephroliths and gallstones is routinely applied in several institutions abroad. The authors report on their initial experiences with intraoperative ultrasonography of different abdominal organs. 相似文献
993.
994.
995.
Daniel Jirák Jan Kríz Vít Herynek Benita Andersson Peter Girman Martin Burian Frantisek Saudek Milan Hájek 《Magnetic resonance in medicine》2004,52(6):1228-1233
A promising treatment method for type 1 diabetes mellitus is transplantation of pancreatic islets containing beta-cells. The aim of this study was to develop an MR technique to monitor the distribution and fate of transplanted pancreatic islets in an animal model. Twenty-five hundred purified and magnetically labeled islets were transplanted through the portal vein into the liver of experimental rats. The animals were scanned using a MR 4.7-T scanner. The labeled pancreatic islets were clearly visualized in the liver in both diabetic and healthy rats as hypointense areas on T2*-weighted MR images during the entire measurement period. Transmission electron microscopy confirmed the presence of iron-oxide nanoparticles inside the cells of the pancreatic islets. A significant decrease in blood glucose levels in diabetic rats was observed; normal glycemia was reached 1 week after transplantation. This study, therefore, represents a promising step toward possible clinical application in human medicine. 相似文献
996.
997.
Association of HLA-DQA1*03011-DQB1*0301 haplotype with the development of respiratory scleroma. 总被引:1,自引:0,他引:1
Luis Alberto Sánchez-Marín Daniel Bross-Soriano José Arrieta Simón Kawa-Karasik Víctor Martínez-Vilchis Rocío Jiménez-Lucio Angélica Olivo-Díaz 《Otolaryngology--head and neck surgery》2007,136(3):481-483
OBJECTIVE: Respiratory scleroma (RS) is a progressive, chronic, granulomatous disease caused by Klebsiella rhinoscleromatis. There is only one report of RS association with HLA-DQ3. In this study, molecular association of HLA class II and RS was determined. STUDY DESIGN AND SETTING: Nine RS patients and 163 healthy controls were compared. DQA1, DQB1, and DRB1 loci were typed. RESULTS: Statistical analysis demonstrated association between DQB1*0301 and susceptibility to RS (P(c) = 0.004). Haplotype analysis showed an association of DQA1*03011-DQB1*0301 (P = 1.21E-19) and DRB1*0407-DQA1*03011-DQB1*0301 (P = 0.0002). CONCLUSIONS: Results established that DQA1*03011-DQB1*0301 haplotype is a strong risk factor for development of RS. 相似文献
998.
Ibrahim Ercan Burak Omür Cakir Tülay Ba?ak Eltaf Ay?a Ozbal Atilla Sahin Gürhan Balci Suat Turgut 《Otolaryngology--head and neck surgery》2006,134(5):751-755
OBJECTIVE: The aim of this study is to investigate dose-dependent effect of the topical application of methotrexate (MTX) in rats on the normal nasal mucosa, liver tissue, liver enzymes, and hemoglobin levels. STUDY DESIGN: Preclinical animal study. SETTING: Twenty male adult wistar albino rats were randomly divided into 4 groups (n=5). A single puff of MTX (2.5 microg) was applied to both nasal cavities 2 times a day. The animals were given MTX 1 day a week in group 1, 3 days a week in group 2, and 5 days a week in group 3. Control group animals were given 1 puff of physiologic saline to both nasal cavities 5 days a week and 2 times a day. After 28 days, liver biopsies, blood samples, and 5 nasal mucosal biopsies were taken. Histological examination was made with respect to certain parameters semiquantitatively (grade 0-3). The aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels and hemoglobin counts were studied from blood samples. RESULTS: There are no statistically significant differences with respect to histopathological parameters between the control group and the groups 1-3 (P>0.05). Histopathological examination of liver tissue did not reveal any evident difference between the control and study groups. Mean AST and ALT as liver function tests and hemoglobin counts were within normal limits. Topical application of MTX at these doses has no toxic effect on the nasal mucosa, the liver tissue, AST and ALT levels, and hemoglobin level. CONCLUSIONS: These results have been encouraging to investigate use of the topical application of MTX in nasal manifestation of autoimmune disease or addition of the topical application of MTX to the steroid treatment in cases with massive nasal polyposis resistant to steroids and prone to recurrence. 相似文献
999.
Miguelina Hernández Héctor Scannone Héctor J Finol Maria E Pineda Irma Fernández Alba M Vargas María E Girón Irma Aguilar Alexis Rodríguez-Acosta 《Experimental and toxicologic pathology》2007,59(2):129-137
This study explored the toxic effects of crotoxin isolated from Crotalus durissus cumanensis venom on the ultrastructure of mice cardiac autonomic nervous system. Mice were intravenously injected with saline (control group) and crotoxin diluted in saline venom (study group) at a dose of 0.107 mg/kg mouse body weight. Samples from the inter-ventricular septum were prepared for electron microscopy after 6 h (G1), 12 h (G2), 24 h (G3) and 48 h (G4). The G1 group showed some cardiomyocyte with pleomorphic mitochondria. Capillary swollen walls, nerve cholinergic endings with depleted acetylcholine vesicles in their interior and other depletions were observed. A space completely lacking in contractile elements was noticed. The G2 group demonstrated a myelinic figure, a subsarcolemic region with few myofibrils and nervous cholinergic terminal with scarce vacuoles in their interior. The G3 group demonstrated a structure with a depleted axonic terminal, mitochondrias varying in size and enhanced electron density. In addition, muscular fibers with myofibrillar structure disorganization, a depleted nervous structure surrounded by a Schwann cell along with an abundance of natriuretic peptides, were seen. An amyelinic terminal with depleted Schwann cell and with scarce vesicles was also observed. Finally, axonic lysis with autophagic vacuoles in their interior and condensed mitochondria was observed in the G4 group. This work describes the first report of ultrastructural damage caused by crotoxin on mice cardiac autonomic nervous system. 相似文献
1000.
G Diéguez A L García M V Conde B Gómez L Santamaría S Lluch 《Microvascular research》1987,33(2):143-154
The carotid rete of Artiodactyla, an intracranial arterial plexus which supplies blood to the brain, has intrigued investigators for a long time. This study was designed to examine the responsiveness of isolated retial arteries (250-700 microns in external diameter) of goat, pig, and cattle. The findings in these arteries were compared to those observed in cerebral arteries (250-650 microns in external diameter) of the same animal species. The magnitude of the arterial responses to potassium chloride varied with the resting tension applied to the tissue. The two types of vessels exhibited similar resting tension values (0.3 g) for maximal tension development in response to potassium chloride; however, the ability of retial vessels to contract in the presence of potassium chloride was consistently smaller than that of cerebral arteries. The contractile response of retial arteries to norepinephrine (10(-9) to 10(-4) M), tyramine (10(-8) to 10(-3) M), and field electrical stimulation (2-16 Hz) was negligible. The same retial arteries exhibited dose-dependent contractions in response to 5-hydroxytryptamine (10(-9) to 10(-5) M) and histamine (10(-9) to 3 X 10(-4) M). Cerebral arteries exhibited larger responses to the vasoactive agents than retial arteries. Our findings indicate that retial arteries have a small vasomotor activity in response to adrenergic stimulation or to vasoactive agents. Therefore, the carotid rete of Artiodactyla may have a low ability to change resistance to blood flow under neural or hormonal influences. 相似文献