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1.
The effects of spironolactone (5% SYC-201G, a preparation developed for clinical use in acne vulgaris by Searle Yakuhin K.K.), which is known to have antiandrogenic effects by competitively inhibiting dihydrotestosterone at androgen receptor sites, was topically applied to the androgen stimulated sebaceous glands of adult female golden hamsters. Androgen stimulation, induced by intramuscular injection of testosterone propionate (TP) every other day over a two week period, resulted in a 2.5 to 2.7 time increase in the size of the sebaceous glands of the hamster pinna. Once-daily treatment with 5% SYC-201G or matching placebo was applied to androgen-stimulated hamsters on one pinna only during the same period as TP injection. Comparison between the treated and untreated sides revealed a significant suppression in the sebaceous gland size (p<0.05) by 5% SYC-201G; no such effect was observed with placebo. The difference in the suppression rate of the sebaceous gland size between 5% SYC-201G (23%) and matching placebo (–4.7%) was significant (p<0.01).  相似文献   
2.
BACKGROUND: Adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) are thought to contribute to the airway inflammation and airway hyper-responsiveness (AHR) of allergic asthma. Some differences from allergic asthma have been noted, including airway neutrophilia, and the involvement of ICAM-1 in toluene diisocyanate (TDI) asthma is currently unclear. OBJECTIVE: We utilized mice lacking ICAM-1 expression (ICAM-1(-/-)) to investigate the role of ICAM-1 in airway inflammation and AHR in TDI-induced asthma. METHODS: Male C57BL/6J mice (ICAM-1(+/+)) and ICAM-1(-/-) mice were intranasally sensitized to TDI solution or solvent alone. Airway inflammation, AHR and cytokine secretion were assessed 24 h after challenge by TDI or solvent. The production of antigen-specific IgG and IgE by TDI sensitized and non-sensitized mice was determined. RESULTS: TDI challenge to ICAM-1(+/+) mice induced an increase in airway inflammatory cell numbers, AHR and cytokine secretion of TNF-alpha, macrophage inflammatory protein-2 (MIP-2), IL-4, IL-5 and IFN-gamma into the bronchoalveolar lavage fluid. All these pathophysiological changes were reduced in ICAM-1(-/-) mice. Serum levels of TDI-specific IgG and IgE of ICAM-1(-/-) and ICAM-1(+/+) mice were comparable. CONCLUSION: These results suggest that ICAM-1 plays an essential role in airway inflammation and AHR in TDI-induced asthma.  相似文献   
3.
The present case report describes a case of ganglioglioma with a distinct sarcomatous component in the left temporal lobe of a 59‐year‐old Japanese man. Neoplastic neuroglial tissue contained both benign and anaplastic glial components with a MIB‐1 labeling index of 0.1% and 12.0%, respectively. Sarcomatous tissue adjacent to the anaplastic glial tissue was dominated by pleomorphic fibroblastic cells with a MIB‐1 labeling index of 10.8%. They were immunoreactive for smooth muscle actin, type IV collagen, and alpha 1 antitrypsin, but not for desmin and CD34. Interestingly, some of the sarcomatous cells were double‐positive for smooth muscle actin and GFAP. The p53 protein had accumulated in the anaplastic astrocytes and sarcomatous cells, but direct DNA sequencing of PCR products failed to detect any mutation in the p53 gene (from exon 4 to exon 10).  相似文献   
4.
A female patient with unilateral gonadal dysgenesis was a mosaic for three cell lines, 45,X/46,X, + marI/46,X, + marII, including two different marker chromosomes. DNA analysis using 17 Y-specific DNA probes revealed that each marker consists of different segments of the Y chromosome.  相似文献   
5.
We develop a compact scanning head for use in laser confocal fluorescence microscopy for in situ fluorescence imaging of organs. The head, cylindrical in shape, has 3.5 mm diameter and 30 mm length, and is thus small enough to operate in a living rat heart. The lateral and axial resolutions, defined as full widths at half maximum (FWHM) of a point spread function (PSF), measures 1.0 and 5.0 microm, respectively, for 488-nm excitation and 1.0 and 5.4 microm, respectively, for 543-nm excitation. The chromatic aberration between 488- and 543-nm laser beams is well suppressed. We perform Ca2+ imaging in cardiomyocytes through the right ventricular chamber of a perfused rat heart in line-scan mode with 2.9-ms time resolution. We also carried out two-color imaging of a fixed mouse heart and liver with subcellular resolution. The compact head of the microscope equipped with a line-scan imaging mode and two-color imaging mode is useful for in situ imaging in living organs with subcellular resolution and can advantageously be applied to in vivo research.  相似文献   
6.
The cavernous body in the lamprey gill filament was studied by electron microscopy. This body lies along the outer border of the axial plate of each gill filament and freely communicates with an afferent filament artery. Two series of blood channels run alternately, passing through the cavernous body, and lead to the marginal channels in the secondary lamellae. On the other hand, narrow blood spaces left in the cavernous body lead to the blood lacunae in the axial plate (osmoregulatory region) and to those in the secondary lamellae (respiratory region). All the blood in the cavernous body is finally collected by an efferent filament artery. The cavernous body is traversed by numerous trabeculae and collagenous columns which run diagonally in the blood spaces to connect the walls of the cavernous body. All the walls of the cavernous body, including trabeculae and collagenous columns, are completely surrounded by the cytoplasmic flanges of specialized cells called here “cavernous body cells.” These cells are about 30 μm in diameter and characterized by (1) association with collagenous columns or trabeculae and also by the presence of (2) coated caveolae and vesicles, (3) vacuoles and (4) cytoplasmic granules in their cytoplasm. These cells are considered to be related to the pillar cells in origin because of their close association with collagenous columns or trabeculae. The functional significance of the cavernous body and the cavernous body cells is discussed.  相似文献   
7.
BACKGROUND: In Japan in 1993, the Japanese Society of Allergology (JSA) developed guidelines for diagnosis and management of asthma (JGL), which were based on the concept that asthma is a chronic inflammatory disorder of the airway. METHODS: This survey study was intended to investigate the recognition and utilization of JGL among physicians who had treated asthma. The survey comprised two methods: a quantitative mail survey and a qualitative door-to-door survey conducted by trained interviewers. RESULTS: In the mail survey, a total of 1028 physicians responded; 552 members of the JSA and 476 nonmembers. Ninety-four percent of JSA members were aware of adult asthma management guidelines, while 53% of nonmembers were aware of them. Although approximately half of the physicians, both members and nonmembers, found differences between the asthma management policies in JGL and their previous policies, most of them utilized JGL once they read it. In the qualitative door-to-door survey, 80-90% of physicians evaluated JGL as good after they read it. CONCLUSIONS: JGL was recognized and utilized by most JSA members, but only half of nonmember physicians were aware of JGL, although they utilized JGL after they read it. Further action to implement JGL among nonspecialist physicians is needed to improve management of asthma.  相似文献   
8.
The myotendinous junction in the skeletal muscle of adult lamprey Lampetra japonica was studied with an electron microscope. Numerous finger-like sarcolemmal invaginations were present at the ends of muscle fibers to form the myotendinous junction. Parietal fibers of each muscle unit showed more closely distributed sarcolemmal invaginations than central fibers. Features of the myotendinous junction. Parietal fibers of each muscle unit showed more closely distributed sarcolemmal invaginations than central fibers. Features of the myotendinous junction generally conform to the accounts in the literature. The sarcolemmal invagination was covered on its sarcoplasmic aspect by the connecting filament layer and the dense amorphous attachment layer, and on the extracellular aspect by the intermediary layer and the external lamina with collagen fibrils arising from the myosepta. Sarcolemmal invaginations were sometimes seen to consist of a pair of sarcolemmas of adjacent muscle fibers within a muscle unit, which is characteristic to the myotendinous junction of lamprey. It is noteworthy that the connecting filament layer is much thinner than that, e.g., in the tadpole tail muscles (Nakao, '74). Furthermore, it is much thicker in the parietal fibers than in the central fibers. The sarcolemma of the terminal segment of the invagination frequently showed specific coupling with cisterns of the sarcoplasmic reticulum (terminal coupling). The external lamina is partially or completely deficient in the terminal segment of sarcolemmal invaginations which form terminal couplings so that collagen fibrils contained in the invagination appear to be in direct contact with the sarcolemma; however, definite relationships of collagen fibrils with the sarcolemma and the external lamina in the terminal segment of invagination still remain obscure. This type of coupling is considered to play a role in the coupling of excitation to contraction of muscle fibers as triads and diads.  相似文献   
9.
There is evidence of an association between major histocompatibility complex (MHC) genes and acute anterior uveitis; here the authors report the frequency of class I and class III MHC phenotypes in 32 Mexican mestizo patients with chronic anterior uveitis and compared them to those present in 100 ethnically matched healthy controls. Results showed in patients statistically significant increased frequencies of HLA-B(27) antigen (pC=0.02, OR=6.33, 95+ CI:1.63-26.47) and the complotype SC(21) (pC=0.04, OR=4.5, 95+ CI:1.40-14.67); the authors found a decreased frequency of HLA-B(35) (p=0.006, OR=0.10, 95+ CI: 0.00-0.65) as compared to normal controls. None of the individuals bearing the SC(21) complotype were positive for HLA-B(27), suggesting independent roles of the class I and class III antigens in the genetic susceptibility to chronic anterior uveitis.  相似文献   
10.
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