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81.
Sanny S W Chung Wengkong Sung Xiangyuan Wang Debra J Wolgemuth 《Developmental dynamics》2004,230(4):754-766
Targeted mutagenesis of the retinoic acid receptor alpha (RAR alpha) gene has revealed its essential role in spermatogenesis. Although cells in all stages of spermatogenesis were detected in RAR alpha(-/-) testes, there was an increase in degenerating pachytene spermatocytes and a temporary developmental arrest in step 8-9 spermatids in the first wave of spermatogenesis, a delay in the onset of the second wave, and a temporary arrest in preleptotene to leptotene spermatocytes in the first, second, and third waves. A striking aspect of the mutant phenotype was the failure of spermatids to align at the tubular lumen at stage VIII. Furthermore, there were missing or decreased numbers of the predicted cell types in tubules, and they exhibited a profound asynchrony of mixed spermatogenic cell types. In vivo bromodeoxyuridine labeling revealed a significant decrease in germ cell proliferation in both juvenile and adult RAR alpha(-/-) testes and confirmed the arrest at step 8-9 spermatids. Retinoid signaling through RAR alpha, thus, appears to be critical for establishment of synchronous progression of spermatogenesis and the subsequent establishment of correct cellular associations. 相似文献
82.
Assessment of immunization as a technique to extend the chilled storage life of vacuum‐packaged lamb
The growth at — 1.5°C of Lactobacillus delbrueckii, a meat spoilage organism, was evaluated on vacuum‐packaged lamb legs obtained from animals immunized against that organism. Growth was significantly lower than that on similarly treated legs obtained from non‐immunized lambs. These findings suggest that immunization against spoilage organisms may contribute toward increasing the chilled storage life of fresh meat. 相似文献
83.
Mark A. Beilke Debra Riding In Rebecca Hamilton Gary A. Stone Elaine K. Jordan Gene Brashears Wayne Nusbaum David Huddleston Clarence J. Gibbs Jr. Maneth Gravell 《Journal of neuroimmunology》1991,33(2):129-143
HLA-DR expression in neuroendothelial cells (NEC) was studied during the course of SIV encephalitis in rhesus monkeys. HLA-DR determinants were detected on NEC in monkeys with SIV encephalitis, but not in control animals. In situ hybridization with an SIV probe indicated that HLA-DR expression was not a consequence of SIV replication within NEC. Cultured rhesus NEC stimulated with gamma interferon expressed HLA-DR to a higher degree than cultured brain fibroblasts or astrocytes. These data support the contention that NEC participate in retrovirus-induced inflammation and autoimmunity within the central nervous system. 相似文献
84.
Clinical phosphorus-31 magnetic resonance spectroscopy (31P MRS) of the liver requires the use of whole-body magnets and of spectroscopy techniques that acquire signal from defined volumes-of-interest within the liver. Such localization techniques and recent clinical studies are briefly reviewed. These studies indicate that (1) high phosphomonoester levels are present in liver diseases involving structural damage, and (2) that MRS of liver tumors may provide a sensitive and rapid indication of response to cancer therapy. Abnormalities of the liver such as alcoholic liver disease, viral hepatitis, and metastasis were analyzed to determine hepatic acid/base status (pH) and to derive absolute molar concentrations of hepatic phosphorus metabolites rather than metabolite ratios. These parameters allow diagnosis and differentiation of several liver pathologies, suggesting an increasing future role of MRS in medical investigation, clinical diagnosis, and patient treatment. 相似文献
85.
Debbie Gearner Thompson RN MS CCRN Debra Gaddy Cohen RN MSN 《Journal of obstetric, gynecologic, and neonatal nursing : JOGNN / NAACOG》1996,25(1):32-38
Care of the newborn diagnosed with a congenital malignancy is a challenge for the neonatal intensive-care unit nurse. Malignancies found in infants differ from those found in older children. Nursing care of the neonate suspected or diagnosed with a congenital malignancy includes standard practices and problem identification as well as interventions unique to the patient with cancer. This article reviews the incidence, diagnosis, treatment, and nursing management of neoplasms diagnosed in neonates. 相似文献
86.
Oli I. Traustason Steven E. Feldon Jay E. Leemaster John M. Weiner 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1988,226(3):206-212
Visual fields of patients with anterior ischemic optic neuropathy (AION) were classified according to quantitative criteria, using the Octopus perimeter. Although a significant altitudinal pattern of field loss was found in 55% of perimetric examinations, the "spared" hemifields routinely showed some loss of sensitivity. This finding, along with the diffuse loss of sensitivity in a high percentage of visual fields, indicates more extensive involvement of the circulation of the anterior optic nerve head than has previously been suggested. Furthermore, patients with diabetes mellitus alone were found to have a statistically separable pattern of visual field loss. The pathophysiologic implications of the visual fields in AION and their relationship to the clinical findings were investigated. 相似文献
87.
Jahrsdörfer B Wooldridge JE Blackwell SE Taylor CM Griffith TS Link BK Weiner GJ 《Journal of leukocyte biology》2005,77(3):378-387
Immunostimulatory oligodeoxynucleotides (IS ODN) can mediate a number of immunologic effects. We previously demonstrated that treatment of B cell chronic lymphocytic leukemia (B-CLL) cells with one class of IS ODN, CpG ODN, alters their phenotype and increases their immunogenicity. Here, we demonstrate that in contrast to the classic understanding of CpG ODN as inhibitors of B cell apoptosis, IS ODN including CpG ODN induce apoptosis in B-CLL cells. It is important that these changes are seen not only with CpG ODN but with ODN that lack the classical CpG motif. B-CLL cells from 20 subjects were treated in vitro with IS ODN for up to 7 days. IS ODN treatment resulted in increased numbers of apoptotic cells in 13 out of 20 B-CLL samples. IS ODN enhanced apoptosis in samples with 13q deletion as a single aberration and had a heterogeneous effect on apoptosis in samples with other aberrations including 17p deletion, 11q deletion, or trisomy 12. Induction of apoptosis did not correlate with expression of the CpG ODN receptor Toll-like receptor 9. Apoptosis was dependent on the activation of caspases and was accompanied by up-regulation of CD95/Fas and its ligand. We conclude that IS ODN including CpG ODN can induce apoptosis of most B-CLL samples. The ability of IS ODN to induce apoptosis differs based on cytogenetic status. Up-regulation of CD95/Fas may play a role in IS ODN-induced apoptosis of B-CLL. 相似文献
88.
89.
Wen FQ Kohyama T Sköld CM Zhu YK Liu X Romberger DJ Stoner J Rennard SI 《Inflammation》2002,26(6):279-290
TGF- is thought to play a central role in pulmonary fibrosis inducing fibroblast differentiation and extracellular matrix synthesis. In human lung fibroblasts, it is still unclear how various TGB- isoforms affect TGF- production and whether glucocorticoids, commonly used agents to treat fibrotic lung disease, modulate these processes. To this end, human fetal lung fibroblasts (HFL-1) were cultured with various concentrations of glucocorticoids (budesonide, dexamethasone or hydrocortisone) with and without TFG-1, -2, and -3. TGF- mRNA was assessed by real time RT-PCR. Smad 2, 3, and 4 and AP-1 complex (c-fos and c-Jun) cellular localization were evaluated by immunostaining. TGF-2 and -3 stimulated TGF-1 production significantly (p < 0.01 relative to control). TGF-1 stimulated TGF-2 production (p < 0.01 relative to control). TGF-3 was undetectable. Glucocorticoids significantly inhibited TGF-1 and -2 production and reduced expression of the upregulated TGF-1 and -2 mRNA induced by exogenous TGF-1, -2 or -3 (p < 0.01 for each) but had no effect on Smads. Although c-jun-related nuclear staining was not intensified in TGF--stimulated cells, it was reduced by glucocorticoids. Thus, TGF- isoforms may stimulate production of various TGF- isoforms in the lung. Glucocorticoids then may block TGF- production by modulating mRNA levels and c-Jun. 相似文献
90.