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991.
992.
Hyperprolactinemia and luteal insufficiency in infertile patients with mild and minimal endometriosis. 总被引:4,自引:0,他引:4
J S Cunha-Filho J L Gross N A Lemos A Brandelli M Castillos E P Passos 《Hormones et métabolisme》2001,33(4):216-220
The objective of the present paper was to assess the presence of hormonal alterations in infertile women with stage I or II endometriosis (Group III, n = 20) compared to fertile women without endometriosis (Group I, n = 14) and to fertile women with endometriosis (Group II, n = 7). Serum levels of FSH, LH, estradiol, TSH, and PRL were measured between days 1 and 5 of the early follicular phase; in the luteal phase, three serum samples were collected for progesterone measurement, and endometrial biopsies were performed. Serum estradiol levels were lower (p = 0.035) in infertile patients with endometriosis than in fertile patients without endometriosis. Six infertile patients with endometriosis presented prolactin levels above 20 ng/ml. This was not observed in the other groups. Luteal insufficiency was more frequent in infertile patients with endometriosis (78.9%) than in fertile patients with (42.9%) or without endometriosis (0%). In a multiple logistic regression analysis, only the presence of endometriosis and infertility was significantly associated with luteal insufficiency. The serum levels of LH, FSH, and TSH were not significantly different among the groups. Luteal insufficiency and altered prolactin secretion were associated with endometriosis, and could be important mechanisms causing infertility in this group of patients. 相似文献
993.
This article describes the organisation of song in the serin (Serinus serinus) and analyses its variation among individuals. Serins have a repertoire of about 50 complex syllables that are sung at a
very fast rate and in a very stereotyped order, forming discrete songs. Songs are high pitched for the serin’s body size.
Song organisation is circular, with a limited number of starting points. Songs can stop at any point in their cycling. Within
songs there are trilled sections and fast, non-repeated sections that account for the greatest part of songs. These two modes
of singing also differ in average inter-element intervals and probably in their respiratory kinematics. Bird repertoire size
was measured and the difficulties of measuring it in this species are discussed. Repertoires are individually specific and
have a variable amount of syllable sharing with other birds. We found evidence for geographical variation in the composition
of repertoires. Considering our current knowledge of song in carduelines, the stereotyped and circular nature of serin song
appear to be unique within this group of birds.
Received: 30 May 2000 / Received in revised from: 14 August 2000 / Accepted: 12 September 2000 相似文献
994.
Bone marrow-derived cells as progenitors of lung alveolar epithelium. 总被引:70,自引:0,他引:70
D N Kotton B Y Ma W V Cardoso E A Sanderson R S Summer M C Williams A Fine 《Development (Cambridge, England)》2001,128(24):5181-5188
We assessed the capacity of plastic-adherent cultured bone marrow cells to serve as precursors of differentiated parenchymal cells of the lung. By intravenously delivering lacZ-labeled cells into wild-type recipient mice after bleomycin-induced lung injury, we detected marrow-derived cells engrafted in recipient lung parenchyma as cells with the morphological and molecular phenotype of type I pneumocytes of the alveolar epithelium. At no time after marrow cell injection, did we detect any engraftment as type II pneumocytes. In addition, we found that cultured and fresh aspirates of bone marrow cells can express the type I pneumocyte markers, T1alpha and aquaporin-5. These observations challenge the current belief that adult alveolar type I epithelial cells invariably arise from local precursor cells and raise the possibility of using injected marrow-derived cells for therapy of lung diseases characterized by extensive alveolar damage. 相似文献
995.
996.
Tetramer dissociation and monomer partial unfolding precedes protofibril formation in amyloidogenic transthyretin variants 总被引:5,自引:0,他引:5
Quintas A Vaz DC Cardoso I Saraiva MJ Brito RM 《The Journal of biological chemistry》2001,276(29):27207-27213
Amyloid fibril formation and deposition is a common feature of a wide range of fatal diseases including spongiform encephalopathies, Alzheimer's disease, and familial amyloidotic polyneuropathies (FAP), among many others. In certain forms of FAP, the amyloid fibrils are mostly constituted by variants of transthyretin (TTR), a homotetrameric plasma protein. Recently, we showed that transthyretin in solution may undergo dissociation to a non-native monomer, even under close to physiological conditions of temperature, pH, ionic strength, and protein concentration. We also showed that this non-native monomer is a compact structure, does not behave as a molten globule, and may lead to the formation of partially unfolded monomeric species and high molecular mass soluble aggregates (Quintas, A., Saraiva, M. J. M., and Brito, R. M. M. (1999) J. Biol. Chem. 274, 32943-32949). Here, based on aging experiments of tetrameric TTR and chemically induced protein unfolding experiments of the non-native monomeric forms, we show that tetramer dissociation and partial unfolding of the monomer precedes amyloid fibril formation. We also show that TTR variants with the least thermodynamically stable non-native monomer produce the largest amount of partially unfolded monomeric species and soluble aggregates under conditions that are close to physiological. Additionally, the soluble aggregates formed by the amyloidogenic TTR variants showed morphological and thioflavin-T fluorescence properties characteristic of amyloid. These results allowed us to conclude that amyloid fibril formation by some TTR variants might be triggered by tetramer dissociation to a compact non-native monomer with low conformational stability, which originates partially unfolded monomeric species with a high tendency for ordered aggregation into amyloid fibrils. Thus, partial unfolding and conformational fluctuations of molecular species with marginal thermodynamic stability may play a crucial role on amyloid formation in vivo. 相似文献
997.
Duodenal somatostatinoma of the ampulla of vater diagnosed by endoscopic fine needle aspiration biopsy: a case report 总被引:4,自引:0,他引:4
BACKGROUND: Duodenal somatostatinoma is a rare neuroendocrine neoplasm. A better prognosis can be obtained if these tumors are resected at an early clinical stage. Endoscopic punch biopsy has been the method most commonly used for the preoperative diagnosis of neuroendocrine duodenal tumors. To the best of our knowledge, endoscopic fine needle aspiration biopsy (FNAB) of duodenal somatostatinoma has not been reported before. CASE: A 41-year-old, black female presented with upper gastrointestinal bleeding as well as elevated bilirubin, liver enzymes and glucose. Computed tomography, esophagogastroduodenoscopy and endoscopic retrograde cholangiopancreatography (ERCP) detected a mass at the region of the ampulla of Vater partially obstructing the pancreatic duct. The initial punch biopsy yielded only intestinal mucosa. Subsequent endoscopic FNAB suggested the diagnosis of a neuroendocrine neoplasm, as confirmed by additional punch biopsies. Immunohistochemical and electron microscopic studies disclosed somatostatin production by the tumor, which was resected through a modified Whipple procedure. The patient recovered fully. CONCLUSION: This case demonstrates the usefulness of endoscopic FNAB in diagnosing submucosal gastrointestinal neuroendocrine tumors. 相似文献
998.
Cardoso CC Garrett T Cayla C Meneton P Pesquero JB Bader M 《Biological chemistry》2004,385(3-4):295-301
Kininogens serve dual functions by forming a scaffold for the assembly of the protein complex initiating the surface-activated blood coagulation cascade and as precursors for the kinin hormones. While rats have three kininogen genes, for mice, cattle, and humans only one gene has been described. Here, we present sequence and expression data of a second mouse kininogen gene. The two genes, kininogen-I and kininogen-II, are located in close proximity on chromosome 16 in a head-to-head arrangement. In liver and kidney, both genes are expressed and for each gene three alternative splice variants are synthesized. Two of them are the expected high and low molecular weight isoforms known from all mammalian kininogens. However, for both genes also a third, hitherto unknown splice variant was detected which lacks part of the high molecular weight mRNA due to splicing from the low molecular weight donor site to alternative splice acceptor sites in exon 10. The physiological functions of the six kininogen isoforms predicted by these findings need to be determined. 相似文献
999.
Silva MG Furtado NA Pupo MT Fonseca MJ Said S da Silva Filho AA Bastos JK 《Microbiological research》2004,159(4):317-322
A strain of Penicillium corylophilum isolated from Brazilian soil sample was submitted to different culture conditions to investigate the production of secondary metabolites with antimicrobial activity. The largest number of conidia was obtained after 5 days of incubation in oat medium and the highest level of antimicrobial activity was produced when the fungus culture was developed in the Czapek medium. The activity against Staphylococcus aureus was found only in the chloroform extract from Czapek culture broth, which also showed activity against Micrococcus luteus. Fumiquinozoline F was isolated from the active chloroform extract by using chromatographic methods. The minimal inhibitory concentration (MIC) values for M. luteus and S. aureus were 99 μg/mL and 137 μg/mL, respectively. 相似文献
1000.
Laport MS de Castro AC Villardo A Lemos JA Bastos MC Giambiagi-deMarval M 《Current microbiology》2001,42(4):264-268
One of the outstanding problems in the field of heat shock response has been to elucidate the mechanism underlying the induction
of heat shock proteins (HSPs). In this work, we initiate an analysis of the expression of heat shock groEL and dnaK genes and their promoters in S. pyogenes. The synthesis of total cellular proteins was studied upon transfer of a log-phase culture from 37°C to 42°C by performing
5-min pulse-labeling experiments with 35S-Met. The heat shock responses in the pathogenic Gram-positive cocci, Enterococcus faecalis and Staphylococcus aureus, were also analyzed.
Received: 12 July 2000 / Accepted: 27 August 2000 相似文献