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排序方式: 共有9199条查询结果,搜索用时 412 毫秒
151.
Suneet P Chauhan Nancy N Lynn Maureen Sanderson Joyce Humphries Jill H Cole James A Scardo 《The journal of maternal-fetal & neonatal medicine》2006,19(11):699-705
OBJECTIVE: To develop a scoring system for the detection of a macrosomic fetus (birth weight (BW) >or= 4000 g) and predict shoulder dystocia among large for gestational age fetuses. STUDY DESIGN: We retrospectively identified all singletons with accurate gestational age (GA) that were large for GA (abdominal circumference (AC) or estimated fetal weight (EFW) >or= 90% for GA) at >or=37 weeks with delivery within three weeks. The scoring system was: 2 points for biparietal diameter, head circumference, AC, or femur length >or=90% for GA, or if the amniotic fluid index (AFI) was >or=24 cm; for biometric parameters <90% or with AFI <24 cm, 0 points. The predictive values for detection of shoulder dystocia were calculated. RESULTS: Of the 225 cohorts that met the inclusion criteria the rate of macrosomia was 39% and among vaginal deliveries (n = 120) shoulder dystocia occurred in 12% (15/120; 95% confidence interval (CI) 7-20%). The sensitivity of EFW >or=4500 g to identify a newborn with shoulder dystocia was 0% (95% CI 0-21%), positive predictive values 0% (95% CI 0-46%), and likelihood ratio of 0. For a macrosomia score >6, the corresponding values were 20% (4-48%), 25% (5-57%) and 2.3. CONCLUSION: Though the scoring system can identify macrosomia, it offers no advantage over EFW. The scoring system and EFW are poor predictors of shoulder dystocia. 相似文献
152.
Roisean E Ferguson Claire Taylor Anthea Stanley Elizabeth Butler Adrian Joyce Patricia Harnden Poulam M Patel Peter J Selby Rosamonde E Banks 《Clinical cancer research》2005,11(9):3439-3445
PURPOSE: The primary purpose of this study was to determine whether mutations of the class I beta-tubulin gene may be implicated in the inherent resistance to tubulin-binding agents (TBA) in renal cancer, with a small number of samples and cell lines also being examined for class I and III beta-tubulin isotype protein expression. EXPERIMENTAL DESIGN: DNA was extracted from 90 renal tumors and the class I beta-tubulin gene analyzed for mutations. For each sample, eight PCRs were used to cover the complete coding sequence with intronic primers ensuring highly homologous pseudogenes were not coamplified. Additionally, expression levels of class I and III beta-tubulin isotypes in 17 matched normal and malignant renal samples and a panel of renal cell carcinoma cell lines with differing intrinsic resistance to the TBAs was examined by Western blotting. RESULTS: Four polymorphic sequence changes of the class I beta-tubulin gene were identified with no mutations. Class I protein expression levels were higher in tumor tissue versus normal tissue, whereas class III expression showed no consistent change. In renal cancer cell lines, a significant correlation between class III isotype expression and vinblastine sensitivity was observed. CONCLUSIONS: These results do not support a role for mutations in the class I beta-tubulin gene in the intrinsic resistance of renal cancer to TBAs. Class III isotype expression may be implicated in resistance in vitro but in vivo, changes in class I isotype expression in renal cell carcinoma tissue may support a role in resistance to the TBAs and warrants further investigation. 相似文献
153.
Glutamate receptor subunits are altered in forebrain and cerebellum in rats chronically exposed to the NMDA receptor antagonist phencyclidine. 总被引:1,自引:0,他引:1
Phencyclidine (PCP) is a noncompetitive antagonist of the N-methyl-D-aspartate (NMDA) glutamate receptor subtype. It produces transient psychoses in normal individuals and exacerbates psychoses in schizophrenics. When administered to rodents, PCP elicits stereotypic behaviors including unrelenting head swaying, hyperlocomotion, and social withdrawal. In this study, we examined the relative distribution of the NMDA receptor subunits, as well as the subunits of its modulating receptor, alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) in the forebrain, hippocampus, and cerebellum of rats chronically exposed to PCP. Rats were injected for 30 days with PCP (10 mg/kg) and age/sex-matched controls were injected for 30 days with saline vehicle. Brain NMDA and AMPA receptor subunit distribution patterns and protein levels were then analyzed by immunocytochemistry and Western blot analysis. Chronic PCP-treated animals showed significant alterations in glutamate receptor subunits, particularly for the NR1, NR2B, NR2C, and NR2D components of the NMDA receptor. AMPA receptor subunits demonstrated few significant changes in subunit availabilities. Western blot analysis largely confirmed the immunocytochemical findings. These results support the conclusion that subunits of the NMDA receptor are selectively altered by chronic PCP antagonism, with minimal to no changes observed in AMPA receptor subunits. Our findings are consistent with the interpretation that a dysfunctional NMDA receptor complex may mediate abnormal glutamatergic neurotransmission and potentially contribute to the complex etiology of cognitive disorders. 相似文献
154.
Adaptation in sensory cortices has been seen as a mechanism allowing the creation of transient memory representations. Here we tested the adapting properties of early responses in human somatosensory areas SI and SII by analysing somatosensory-evoked potentials over the very first repetitions of a stimulus. SI and SII generators were identified by well-defined scalp potentials and source localisation from high-density 128-channel EEG. Earliest responses (~20 ms) from area 3b in the depth of the post-central gyrus did not show significant adaptation to stimuli repeated at 300 ms intervals. In contrast, responses around 45 ms from the crown of the gyrus (areas 1 and 2) rapidly lessened to a plateau and abated at the 20th stimulation, and activities from SII in the parietal operculum at ~100 ms displayed strong adaptation with a steady amplitude decrease from the first repetition. Although responses in both SI (1–2) and SII areas showed adapting properties and hence sensory memory capacities, evidence of sensory mismatch detection has been demonstrated only for responses reflecting SII activation. This may index the passage from an early form of sensory storage in SI to more operational memory codes in SII, allowing the prediction of forthcoming input and the triggering of a specific signal when such input differs from the previous sequence. This is consistent with a model whereby the length of temporal receptive windows increases with progression in the cortical hierarchy, in parallel with the complexity and abstraction of neural representations. 相似文献
155.
156.
Adolescence is a period of physical, cognitive, psychosocial, and moral development that often results in risk-taking behavior. As a consequence, adolescents are at high risk for sexually transmitted disease (STD). Two of the most common STDs in the United States, chlamydia and human papillomavirus (HPV), affect millions of adolescent women. HPV, contrasted with chlamydia, poses a unique challenge to health care providers. In addition to causing genital warts, HPV has been shown to be the causative agent in the development of cervical cancer. Interventions that are effective in decreasing the transmission of chlamydia, such as increasing condom use, are less effective in prevention of HPV. Efforts to increase adolescent awareness of HPV, to increase age of first coitus, and to decrease numbers of sexual partners are more effective for HPV prevention. Early screening for HPV, smoking cessation, and health promotion may be effective in decreasing the incidence of cervical cancer in young women. Nurse practitioners and other primary health care providers need a more holistic approach to the prevention of HPV in adolescent women. 相似文献
157.
Malcolm P. Chelliah BA Zachary Zinn MD Phoung Khuu MD Joyce M. C. Teng MD PhD FAAD 《Pediatric dermatology》2018,35(4):e224-e227
Epidermolysis bullosa is a rare blistering skin disorder that is challenging to manage because skin fragility and repeated wound healing cause itching, pain, limited mobility, and recurrent infections. Cannabidiol, an active cannabinoid found in cannabis, is postulated to have antiinflammatory and analgesic effects. We report 3 cases of self‐initiated topical cannabidiol use in patients with epidermolysis bullosa in an observational study. One patient was weaned completely off oral opioid analgesics. All 3 reported faster wound healing, less blistering, and amelioration of pain with cannabidiol use. Although these results demonstrate promise, further randomized, double‐blind clinical trials are necessary to provide scientific evidence of our observed benefits of cannabidiol for the treatment of epidermolysis bullosa. 相似文献
158.
159.
Wesley H. Self MD MPH Joyce Mickanin MSN RN Carlos G. Grijalva MD MPH Freda H. Grant MT ASCP Michelle C. Henderson MSN RN Glenda Corley MT ASCP D. Glen Blaschke II MD Candace D. McNaughton MD MPH Tyler W. Barrett MD MSCI Thomas R. Talbot MD MPH Barbara R. Paul MD 《Academic emergency medicine》2014,21(3):274-282
160.
Leila Akkari Vasilena Gocheva Jemila C. Kester Karen E. Hunter Marsha L. Quick Lisa Sevenich Hao-Wei Wang Christoph Peters Laura H. Tang David S. Klimstra Thomas Reinheckel Johanna A. Joyce 《Genes & development》2014,28(19):2134-2150
During the process of tumor progression, cancer cells can produce the requisite growth- and invasion-promoting factors and can also rely on noncancerous cells in the tumor microenvironment as an alternative, cell-extrinsic source. However, whether the cellular source influences the function of such tumor-promoting factors remains an open question. Here, we examined the roles of the cathepsin Z (CtsZ) protease, which is provided by both cancer cells and macrophages in pancreatic neuroendocrine tumors in humans and mice. We found that tumor proliferation was exclusively regulated by cancer cell-intrinsic functions of CtsZ, whereas tumor invasion required contributions from both macrophages and cancer cells. Interestingly, several of the tumor-promoting functions of CtsZ were not dependent on its described catalytic activity but instead were mediated via the Arg–Gly–Asp (RGD) motif in the enzyme prodomain, which regulated interactions with integrins and the extracellular matrix. Together, these results underscore the complexity of interactions within the tumor microenvironment and indicate that cellular source can indeed impact molecular function. 相似文献