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991.
Neovaginal construction with buccal mucosal grafts 总被引:5,自引:0,他引:5
Several surgical techniques have been designed to construct a neovagina that will be satisfying in appearance, function, and feeling when the vagina is congenitally absent. However, no method has yet been approved as a perfect solution. With the aim of solving the problems with conventional methods, the authors describe a new surgical technique that is simple and safe for treating vaginal agenesis. This technique consists of creating a mucosal lining of the neovaginal cavity using multiple full-thickness buccal mucosal patch grafts. Four patients with congenital absence of the vagina treated with this technique are presented. This surgical procedure created a mucus-providing lining inside the neovagina. Selecting the donor site in the oral region resulted in an inconspicuous donor-site scar. Histologically, the neovaginal lining was confirmed as mucosal, and the cream-colored viscous fluid found in the neovaginal cavity was confirmed as mucus. At a mean follow-up period of 15 months, the neovagina remained adequate in depth and width. All of the patients were interviewed to evaluate the function of the neovagina. Each patient reported having regular sexual intercourse and that the neovagina had felt normal to their partners. The encouraging results obtained in four cases suggest that this new technique deserves further application. 相似文献
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In the present study, the possible role of ureogenesis to avoid the accumulation of toxic ammonia to a lethal level under
hyper-ammonia stress was tested in the air-breathing walking catfishClarias batrachus by exposing the fish at 25 mM NH4Cl for 7 days. Excretion of ammonia by the NH4Cl-exposed fish was totally suppressed, which was accompanied by significant accumulation of ammonia in different body tissues.
The walking catfish, which is otherwise predominantly ammoniotelic, turned totally towards ureotelism from ammoniotelism with
a 5-to 6-fold increase of urea-N excretion during exposure to higher ambient ammonia. Stimulation of ureogenesis was accompanied
with significant increase of some of the key urea cycle enzymes such as carbamyl phosphate synthetase (urea cycle-related),
argininosuccinate synthetase and argininosuccinate lyase both in hepatic and non-hepatic tissues. Due to this unique physiological
strategy of turning towards ureotelism from ammoniotelism via the induced urea cycle, this air-breathing catfish is able to
survive in very high ambient ammonia, which they face in certain seasons of the year in the natural habitat. 相似文献
997.
Idiopathic cases of male infertility from a region in India show low incidence of Y-chromosome microdeletion 总被引:2,自引:0,他引:2
Ambasudhan R Singh K Agarwal JK Singh SK Khanna A Sah RK Singh I Raman R 《Journal of biosciences》2003,28(5):605-612
Chromosomal and Y-chromosomal microdeletion analysis has been done in cases of idiopathic infertility with the objective of
evaluating the frequency of chromosomal and molecular anomaly as the causal factor of infertility. Barring a few cases of
Klinefelter syndrome (XXY or XY/XXY mosaics), no chromosomal anomaly was encountered. Y-microdeletion was analysed by PCR-screening
of STSs from different regions of the AZF (AZFa, AZFb, AZFc) on the long arm of the Y, as well as by using DNA probes of the
genes RBM, DAZ (Yq), DAZLA (an autosomal homologue of DAZ) and SRY (Yp; sex determining gene). Out of 177 cases examined,
9 (azoospermia -8 and oligoasthenospermia -1) showed partial deletion of AZF. The size of deletion varied among patients but
AZFc was either totally or partially removed in all of them. In contrast, no deletion was detected in AZFa. Testis biopsy
done on a limited number of cases (50) showed diverse stages of spermatogenic arrest with no specific correlation with the
genotype. The frequency of Y-chromosome microdeletion in our samples (∼ 5%) is much lower than the frequency (∼ 10%) reported
globally and the two previous reports from India. We contend that the frequency may be affected by population structures in
different geographical regions. 相似文献
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999.
Effects of vitamin E on microsomal Ca(2+) -ATPase activity and calcium levels in streptozotocin-induced diabetic rat kidney 总被引:1,自引:0,他引:1
Dogru Pekiner B Daş Evcimen N Ulusu NN Bali M Karasu C 《Cell biochemistry and function》2003,21(2):177-182
Vitamin E treatment has been found to be beneficial in preventing or reducing diabetic nephropathy. Increased tissue calcium and abnormal microsomal Ca(2+)-ATPase activity have been suggested as contributing factors in the development of diabetic nephropathy. This study was undertaken to test the hypothesis that vitamin E reduces lipid peroxidation and can prevent the abnormalities in microsomal Ca(2+)-ATPase activity and calcium levels in kidney of streptozotocin (STZ)-induced diabetic rats. Male rats were rendered diabetic by a single STZ injection (55 mg x kg(-1) i.p.). After diabetes was verified, diabetic and age-matched control rats were untreated or treated with vitamin E (400-500 IU kg(-1) x day(-1), orally) for 10 weeks. Ca(2+)-ATPase activity and lipid peroxidation (MDA) were determined spectrophotometrically. Blood glucose levels increased approximately five-fold (> 500 mg x dl(-1)) in untreated-diabetic rats but decreased to 340+/-27 mg x dl(-1) in the vitamin E treated-diabetic group. Kidney MDA levels did not significantly change in the diabetic state. However, vitamin E treatment markedly inhibited MDA levels in both control and diabetic animals. Ca(2+)-ATPase activity was 0.483+/-0.008 U l(-1) in the control group and significantly increased to 0.754+/-0.010 U l(-1) in the STZ-diabetic group (p < 0.001). Vitamin E treatment completely prevented the diabetes-induced increase in Ca(2+)-ATPase activity (0.307+/-0.025 U l(-1), p < 0.001) and also reduced the enzyme activity in normal control rats. STZ-diabetes resulted in approximately two-fold increase in total calcium content of kidney. Vitamin E treatment led to a significant reduction in kidney calcium levels of both control and diabetic animals (p < 0.001). Thus, vitamin E treatment can lower blood glucose and lipid peroxidation, which in turn prevents the abnormalities in kidney calcium metabolism of diabetic rats. This study describes a potential biochemical mechanism by which vitamin E supplementation may delay or inhibit the development of cellular damage and nephropathy in diabetes. 相似文献
1000.
Polysaccharopeptides of Coriolus versicolor: physiological activity, uses, and production 总被引:15,自引:0,他引:15
The protein-bound polysaccharides or polysaccharopeptides produced by Coriolus versicolor are effective immunopotentiators, which are used to supplement the chemotherapy and radiotherapy of cancers and various infectious diseases. Antitumor activity of polysaccharopeptides has been documented. Several kinds of protein-bound polysaccharides have been shown to be produced by the white rot fungus, C. versicolor. Although some of these polymers are structurally distinct, they are not distinguishable in terms of their physiological activity. This review focuses on the physiologically active polysaccharopeptides of C. versicolor. In nature, C. versicolor occurs as a mushroom body, but the fungus can be grown as mycelial biomass in submerged culture in bioreactors. Mushrooms gathered in the wild, cultivated mushrooms, and the mycelial biomass of submerged culture are used to produce the polysaccharopeptides. Submerged cultures are typically carried out in batches lasting 5-7 days and at 25-27 degrees C. Hot water extraction of the biomass is used to recover the thermostable polysaccharopeptides that are concentrated, purified, and dried into a powder for medicinal use. In view of the documented physiological benefits of these compounds, extensive research is underway on the structure, composition, production methods, and use of new C. versicolor strains for producing the therapeutic biopolymers. Properties, physiological activity, recovery, and purification of the bioactive polysaccharopeptides are discussed. 相似文献