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1.
Nine main organs in the mouse were studied by ESR spectroscopy at 77K. Manganese ions were readily detected in the pancreas, small intestine, stomach and kidney. In particular, the pancreas gave strong ESR signals for the transition metal, suggesting that Mn(II) plays an important role in pancreatic function. All organs reveal different ESR spectra indicating organ specificity. C-centered radical, R-OO radical and C0Q10 or ascorbate radical are stable in the tissue. In the brain, heart and pancreas, N-centered radical heme-NO adduct was detected at 6 and 24 h after excision since common process is involved in tissue degeneration and ESR is sensitive to proteolysis and necrosis of tissues. In endotoxemia and/or CDE-diet-induced pancreatic lesions, R-OO radical and Mn(II) ion were detected in the signal at 77K. By the spin-trapping method (DMPO) at 25 degrees C, DMPO-OH adduct and 3-Line and 6-Line were detected in CDE diet-induced acute pancreatitis. These results suggest that damaged pancreatic tissues are in a highly oxidative environment that probably contains oxygen radicals, and that free radicals are considered to play an important role in the development of pancreatic lesions.  相似文献   
2.
Lymphocytic adenohypophysitis is considered to be an inflammatory disease of the adenohypophysis that is commonly present with visual disturbance and hypopituitarism. Its etiology remains unclear but it is often related to an autoimmune disorder involving other organs, such as the thyroid, parathyroid, or adrenal glands. We encountered a rare case of lymphocytic adenohypophysitis associated with sarcoidosis of the lung and eye during the follow-up period. A 23-year-old woman was hospitalized in July 1986, with a one-month history of headache and visual disturbances which began three days after her second normal delivery. On admission, she showed slight visual impairment and had a left temporal superior quadrantanopia. Endocrinological evaluation revealed thyroid and adrenal hypofunction, and low response of human growth hormone to the loading test. A skull X-ray showed normal shaped sella with some erosion of the dorsum. CT scan showed a rounded contrast-enhanced intrasellar mass extending into the suprasellar cistern. MRI (SR: 500/30) showed a homogeneous low intensity mass which contained a small high intensity area on the relative T2-weighted image (2000/50). A biopsy was performed via right frontotemporal craniotomy. The consistency of the resected tissue was firmer than that of pituitary adenoma. Histologically, the tissue showed diffuse lymphocytic infiltration with some normal adenohypophysis. Her postoperative course was uneventful and the visual impairment improved two months later after the operation. Six months after the operation, she was readmitted with complaints of general fatigue and breathlessness. Chest X-ray showed diffuse infiltration throughout both lung fields, but there was no bilateral hilar lymphadenopathy.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
We examined the binding of [3H]U-46619, a thromboxane A2 agonist, to human and guinea pig platelets and the binding of [3H]SQ 29,548, a thromboxane A2 antagonist, to human, rat and guinea pig platelets. KW-3635 (sodium (E)-11-[2-(5,6-dimethyl-1- benzimidazolyl)ethylidene]-6,11-dihydrodibenz[b,e]oxepin-2-c arboxylate monohydrate) concentration-dependently inhibited the [3H]U-46619 binding to human and guinea pig platelets with inhibition constants of 1.2 nM and 2.7 nM, respectively. KW-3635 also potently inhibited the [3H]SQ 29,548 binding to human and guinea pig platelets with inhibition constants of 1.9 nM and 3.2 nM, respectively. In contrast, KW-3635 was less active against thromboxane A2/prostaglandin H2 receptors in rat platelets with an inhibition constant of 97 nM. KW-3635 at 10(-5) M did not antagonize various receptors including prostaglandin E2, prostaglandin I2 and neurotransmitters. In addition, 10(-5) M KW-3635 did not alter the prostaglandin D2-induced cAMP accumulation in EBTr cells. KW-3635 was inactive towards thromboxane synthase, cyclooxygenase and prostaglandin I2 synthase up to 10(-5) M. KW-3635 slightly inhibited 5-lipoxygenase with an IC50 value of 71 microM. These data indicate that KW-3635 is a potent and selective non-prostanoic thromboxane A2 antagonist, and it can recognize the species differences in thromboxane A2/prostaglandin H2 receptors.  相似文献   
4.
An attempt was made to isolate the active component which exhibits an improving effect on renal function from Salviae Miltiorrhazae Radix (Chinese crude drug). Systematic isolation from aqueous extract of Salviae Miltiorrhizae Radix was carried out, and Compound 1 was found to be more effective than any of the other constituents in improving renal functional parameters; that is, a marked reduction of glomerular filtration rate following adenine ingestion was improved by administration of this substance. The renal plasma flow and renal blood flow were also increased in renal failure rats. On the basis of chemical and spectroscopic data, Compound 1 was shown to be identical with magnesium lithospermate B.  相似文献   
5.
6.
Renal responses to magnesium lithospermate B   总被引:5,自引:0,他引:5  
Renal responses to magnesium lithospermate B isolated from Salviae miltiorrhizae radix were examined in normal rats. Urinary sodium, potassium, prostaglandin E2 and kallikrein excretion was significantly increased after magnesium lithospermate B administration, whereas excretion of urinary 6-keto-prostaglandin F1 alpha and thromboxane B2 was unchanged. Rats administered with the drug also revealed a slight elevation of plasma renin activity and the levels of angiotensins I and II. Plasma aldosterone was decreased slightly. No significant changes were observed in angiotensin-converting enzyme or blood pressure.  相似文献   
7.
Between January 1993 and December 2001, we employed percutaneous cardiopulmonary support (PCPS) in 35 patients. PCPS was used for postcardiotomy in 25 of these patients who could not be weaned from cardiopulmonary bypass (CPB) because of severe cardiogenic shock. In the other 10 patients, PCPS was used for a non-surgical disease. Twenty-nine patients (82.9%) were weaned from PCPS, and 28 (80.0%) survived. The other 7 patients (20.0%) died due to postoperative complications. The causes of death were multiple organ failure (MOF) due to wound bleeding, low cardiac output syndrome (LOS), myonephropathic metabolic syndrome (MNMS) with severe lower limbs ischemia, cerebrovascular accident (CVA), and sepsis. The first cause for the complications was postoperative sustained severe heart failure. To improve the survival rate, it was necessary to prevent bleeding and begin PCPS at an earlier stage.  相似文献   
8.
Lobular carcinoma of the male breast is very rare, because lobules do not exist in the male mammary gland. Seven cases of lobular carcinoma of the male breast have been reported in Europe and U.S.A., although no case in Japan. We encountered a very rare case of the lobular carcinoma of 74-year-old male breast. Histopathological examinations of both primary tumor and recurrent tumors of the skin led to the diagnosis of lobular carcinoma.  相似文献   
9.
Chromosome 1p36 deletion syndrome is characterized by hypotonia, moderate to severe developmental and growth retardation, and characteristic craniofacial dysmorphism. Muscle hypotonia and delayed motor development are almost constant features of the syndrome. We report a 4-year-old Japanese girl with 1p36 deletion syndrome whose muscle pathology showed congenital fiber type disproportion (CFTD) myopathy. This is the first case report of 1p36 deletion associated with CFTD. This association may indicate that one of the CFTD loci is located at 1p36. Ski proto-oncogene −/− mice have phenotypes that resemble some of the features observed in patients with 1p36 deletion syndrome. Because fluorescent in situ hybridization analysis revealed that the human SKI gene is deleted in our patient, some genes in 1p36, including SKI proto-oncogene, may be involved in muscle hypotonia and delayed motor development in this syndrome. Received: March 4, 2002 / Accepted: July 7, 2002  相似文献   
10.
1. To compare the properties of the vestibulocollic reflex (VCR) with those of vestibular neurons projecting to the neck [vestibulocollic (VC) neurons], we have studied the behavior of the latter in the decerebrate cat. Neurons were identified by their antidromic responses to stimulation in C1-C2, but not C5. Responses to stimulation of vestibular and neck receptors were produced by rotation of the body and head in vertical planes. 2. We determined the plane of whole body (vestibular) or body with head counter-rotated (neck) rotation, which produced the maximal modulation of each neuron (response vector orientation). Neuron dynamics were then studied with sinusoidal (0.02-2 Hz) stimuli aligned with this orientation. 3. On the basis of dynamics and vector orientation, the neuron was assigned a vestibular input classification of otolith, vertical canal, otolith + canal, or spatial-temporal convergence (STC). 4. The properties of this sample of VC neurons are similar to those of a larger population of vestibular neurons whose projection was not identified. For example, the distributions of cells with different types of vestibular inputs were roughly the same; in particular, few cells showed STC responses. In addition, there was no evidence of significant convergence of like canals across the midline (e.g., right anterior + left anterior). 5. Also similar to the larger unidentified population, 80% of VC neurons tested for neck input received such an input. The neck and vestibular responses tended to be antagonistic; the vector orientations were usually opposite, and the response gains and phases similar.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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