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排序方式: 共有1783条查询结果,搜索用时 15 毫秒
1.
Hassen Lena M. Albarrak Rana A. Albahlal Reem A. Alsaqabi Dimah K. Hassen Ikhlass M. Daghestani Maha H. Alqurtas Eman M. Alkhalaf Abdulaziz T. Bedaiwi Mohammed K. Omair Mohammed A. Almaghlouth Ibrahim A. 《Quality of life research》2022,31(11):3229-3239
Quality of Life Research - The COVID-19 pandemic might add to the stressors experienced by people living with rheumatic diseases. This study aimed to examine rheumatic patients’ functional... 相似文献
2.
Ahmed M. Abu El-Asrar Eman S. Kahtani Khalid F. Tabbara 《Documenta ophthalmologica. Advances in ophthalmology》1995,89(4):313-320
In this report we describe, herewith, a patient with primary pigmentary dystrophy of the retina (retinitis pigmentosa) associated with unilateral retinal arteriovenous communication and exudative retinal detachment. The patient had complete resolution of the retinal detachment following laser photocoagulation treatment. Such association has not been previously reported. 相似文献
3.
Human uterine leiomyoma cells: binding and growth responses to epidermal growth factor, platelet-derived growth factor, and insulin 总被引:8,自引:0,他引:8
Y M Fayed J C Tsibris P W Langenberg A L Robertson 《Laboratory investigation; a journal of technical methods and pathology》1989,60(1):30-37
The specific binding of epidermal growth factor (EGF), platelet-derived growth factor (PDGF) and insulin were measured in matching cultures of human leiomyoma and myometrial cells, along with the effects of these proteins on DNA and protein syntheses. Scatchard analyses of the binding data revealed that the EGF receptor sites/cell were significantly lower in leiomyoma than myometrial cultures. Two types of PDGF binding were observed when porcine PDGF was used, and one type was seen with human PDGF. By contrast to EGF, more PDGF receptor sites/cell were found in leiomyoma than myometrium but the receptor affinity was higher in the latter. Insulin binding was similar among the myometrial and leiomyoma cells. Protein synthesis was stimulated 3-fold by EGF, PDGF, or insulin in both cell types. DNA synthesis, was higher in myometrial than leiomyoma cells in the basal state and was stimulated by EGF, insulin, or PDGF. A synergistic stimulation (p less than 0.02) of DNA synthesis was observed in both myometrial and leiomyoma cells when EGF was added with insulin. The addition of PDGF with insulin caused only additive stimulation of DNA synthesis. However, the addition of EGF with PDGF caused a synergistic decrease (p less than 0.05) in DNA synthesis by myometrial but no leiomyoma cells. Cultures of human vascular smooth muscle cells obtained from umbilical veins gave results similar to those from myometrium. These findings single out the EGF receptor and EGF, or perhaps an EGF-like growth factor, and to a lesser degree PDGF, as potential regulators of uterine leiomyomata. 相似文献
4.
Al-Baker EA Oshin M Hutchison CJ Kill IR 《Mechanisms of ageing and development》2005,126(6-7):664-672
A major cause of ageing is thought to be the accumulation of damage to macromolecules. Accumulation to DNA damage in cells therefore presupposes that aged cells are unable to repair this damage. We have used the in vitro model of cellular ageing to test the idea that senescent cells are deficient in some aspect of DNA repair. Using the alkaline single cell gel electrophoresis assay (comet assay), we have determined the responses of young and senescent human dermal fibroblasts to DNA damage caused by exposure to UVC light. At low doses of UVC, senescent cells generate smaller comets than young cells whilst at medium doses the situation is reversed. At high doses, young and senescent cells respond similarly to one another. Time course experiments revealing repair of DNA damage show that senescent cells generate larger comets than young cells at early stages of repair suggesting that either senescent cells bear more damage per genome than do young cells or that senescent cells are more efficient at excising bulky adducts from DNA. Cells maintained in low levels of serum irrespective of age are less able to repair DNA damage compared with cells maintained in high levels of serum, and furthermore young and senescent cells maintained in high levels of serum are equally able to repair DNA damage. Our data, therefore, reveal both age-dependent and age-independent responses to UV-induced DNA damage. Use of the comet assay highlights the heterogeneity of cellular responses to genotoxic stress. 相似文献
5.
Task-specific neural activity in the primate prefrontal cortex 总被引:12,自引:0,他引:12
Real-world behavior is typically more complicated than a one-to-one mapping between a stimulus and response; the same stimulus can lead to different behaviors depending on the situation, or the same behavior may be cued by different stimuli. In such cases, knowledge of the formal demands of the task at hand is required. We found that in monkeys trained to alternate between three tasks, the activity of many neurons in the prefrontal cortex was task dependent. This included changes in overall firing rate, in firing-rate profiles (shape of responses over time), and in stimulus and response selectivity. These findings support the hypothesis that a major prefrontal function is the acquisition and implementation of task context and the "rules" used to guide behavior. 相似文献
6.
Reactive oxygen species (ROS), represented by superoxide, hydrogen peroxide and hydroxyl radicals, have been implicated in many diseases including cancer. ROS have been known to play an important role in the initiation and promotion of multistep carcinogenesis. The cellular antioxidants play a crucial role in protection against neoplastic disease. However, very little is known about the antioxidant defense in cervical carcinoma. This is addressed in the present study. Lipid peroxides, glutathione content and the activities of antioxidant enzymes, together with vitamin C and E content, were estimated in patients who had carcinoma of the cervix, and the values were compared with those of normal women. The results showed a remarkable reduction in the content of glutathione, vitamin E and C. Activities of glutathione peroxidase and superoxide dismutase were also reduced in cervical cancer compared to normal controls (P < 0.001). This reduction was more marked in late stages (III, IV) than in early stages (I, II) (P < 0.001). Glutathione was reduced more in poorly differentiated tumors (grade III) than in well and moderately differentiated ones (grade I, II) (P < 0.05). Levels of lipid peroxides were found to be significantly higher in malignant than in normal tissue samples and their levels were correlated with advanced clinical stage (P < 0.001). Our results suggest impaired antioxidant status in carcinoma of the cervix. This impairment is related to tumor progression. 相似文献
7.
Lange CG Lederman MM Madero JS Medvik K Asaad R Pacheko C Carranza C Valdez H 《Journal of acquired immune deficiency syndromes (1999)》2002,30(1):33-40
We compared immune phenotypes, lymphocyte proliferation (LP), and delayed type hypersensitivity (DTH) responses in 28 male antiretroviral treatment-naive and experienced HIV-1-infected patients, matched pair-wise according to age and CD4+ T-lymphocyte count. Median CD4+ T-lymphocyte counts were 441 cells/microL and 483 cells/microL and median CD4+ T-lymphocyte nadirs were 435 cells/microL and 150 cells/microL in both groups, respectively. Absolute numbers of circulating T-lymphocyte subpopulations and proportions of naive and memory T-lymphocytes were comparable in the two groups. Untreated patients had greater proportions of activated CD4+ (p <.05) and CD8+ (p <.01) T-cells expressing human leukocyte antigen (HLA)DR and CD38 and fewer CD8+ cells expressing CD28 (p <.05). DTH and LP responses were comparable in both groups except for HIVp24, LP responses, and mumps DTH responses, which were of greater magnitude in the group treated with highly active antiretroviral therapy (HAART) (p <.05). Thus, HIV-1-infected patients who experienced substantial increases in CD4+ T-lymphocyte counts after suppression of viral replication on HAART had fewer activated lymphocytes and similar immune function when compared with findings in untreated patients with similar CD4+ T-cell counts. HIV replication has minimal real-time effect on CD4+ T-cell function in response to non-HIV antigens but helper T-cell responses to HIV-gag antigen are impaired during ongoing viral replication and may be restored by antiretroviral therapy. 相似文献
8.
Azza Farag Mostafa Hammam Nada Alnaidany Eman Badr Mustafa Elshaib Aliaa El-Swah Wafaa Shehata 《The Journal of clinical and aesthetic dermatology》2021,14(2):14
BACKGROUND: Melasma is a chronic hypermelanotic disorder that is challenging to treat; no single effective therapeutic agent for it has been discovered. Methimazole, an oral antithyroid drug, has a skin depigmenting effect when used topically. OBJECTIVE: We sought to evaluate the efficacy and safety of methimazole, applied during microneedling sessions and additional topical use in between sessions, for the treatment of melasma. METHODS: This split-face study included 30 Egyptian patients with melasma, each of whom received 12 microneedling sessions once per week for 12 weeks followed by topical methimazole on the right side of face and placebo on the left side. In between the sessions, topical methimazole 5% cream was applied twice per day on the right side and placebo on the left side. Assessments were performed using the Hemi-melasma Area and Severity Index (hemi-MASI) percentage of improvement, patient satisfaction, dermoscopy, and thyroid-stimulating hormone (TSH) serum levels. RESULTS: There were significant clinical and dermoscopic improvements; hemi-MASI scores on the methimazole-treated right sides were decreased (p<0.001). The percent of hemi-MASI score improvement was significantly associated with the malar pattern (p=0.031) and epidermal type (p=0.04) of melasma. About 70 percent of our studied patients reported being satisfied with their treatment response (7% excellent, 33% good, 30% fair). No significant local or systemic side effects were observed. Pre- and posttreatment serum TSH levels were within the normal range in all treated cases. CONCLUSIONS: Methimazole has the potential to be a safe and promising therapeutic agent for the treatment of melasma via dermapen-delivered microneedling sessions with topical use in between sessions. 相似文献
9.
Trippodo NC Fox M Monticello TM Panchal BC Asaad MM 《Journal of cardiovascular pharmacology》1999,34(6):782-790
Vasopeptidase inhibitors are single molecules that inhibit neutral endopeptidase (NEP) and angiotensin-converting enzyme (ACE) simultaneously. Omapatrilat, the first in this new class of cardiovascular agents, potentiates vasodilatory and cardioprotective peptides and represses angiotensin II. This study compared the effects of omapatrilat with those of a pure ACE inhibitor on cardiac geometry and survival in animals with heart failure. BIO TO-2 cardiomyopathic hamsters (CMHs) in the early stages of dilated heart failure were treated with vehicle or maximal ACE inhibitory doses of captopril (750 micromol/kg/day) or omapatrilat (200 micromol/kg/day). Prolonged vasopeptidase inhibition increased median survival time after the start of treatment by 99 and 31% compared with vehicle and captopril, respectively (median survival times: 146, 221, and 290 days with vehicle, captopril, and omapatrilat, respectively; p < 0.001 for all comparisons). In similar CMHs, captopril or omapatrilat administered for 2 months significantly (p < 0.05) decreased heart weight, pulmonary congestion (lung weight), and left ventricular (LV) chamber volume compared with vehicle. Omapatrilat significantly increased LV mass-to-volume ratio compared with vehicle and captopril. Omapatrilat, but not captopril, significantly increased urinary atrial natriuretic peptide excretion, indicating NEP inhibition. Thus vasopeptidase inhibition with omapatrilat was more effective than ACE inhibition with captopril in preventing changes in LV geometry and premature mortality in hamsters with dilated heart failure. 相似文献
10.
The ethereal extract of AJUGA IVA (L.) S CHREB. roots, yielded 4 ecdysones. Three were proved to be cyasterone, makisterone A and ecdysterone, by using UV, IR, MS spectral methods and comparison with standard samples. Spectral data indicate that the fourth ecdysone is similar to cyasterone but having an additional hydroxy group in the side-chain. The chromatographic pattern of ecdysone content in roots, stems and leaves is presented as well as a rapid and simple Semiquantitative method for their estimation. The roots had the highest total content (0.381%). 相似文献