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101.
Twenty-four patients with inflammatory lesions of the abdominal wall were examined by ultrasonography. Nine of these patients underwent computed tomographic (CT) scanning as well. Both ultrasonography and CT clearly delineated the exact location and extent of abdominal wall abscesses. Abscesses were easily differentiated from cellulitis or phlegmon with ultrasound. The peritoneal line was more clearly delineated on ultrasonograms than on CT scans; abscesses were also more distinct on the ultrasonograms because of their low echogenicity compared with the surrounding structures. Gas bubbles, fat density with specific low attenuation values, and underlying inflamed bowel loops in obese patients with Crohn's disease were better delineated by CT. 相似文献
102.
Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos 总被引:8,自引:2,他引:8
Yang HW; Hwang KJ; Kwon HC; Kim HS; Choi KW; Oh KS 《Human reproduction (Oxford, England)》1998,13(4):998-1002
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture
environment differs from in-vivo conditions in that the oxygen
concentration is higher, and in such conditions the mouse embryos show a
higher concentration of reactive oxygen species (ROS) in simple culture
media. ROS are believed to cause damage to cell membranes and DNA
fragmentation in somatic cells. This study was conducted to ascertain the
level of H2O2 concentration within embryos and the morphological features
of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31
fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was
obtained from the IVF-embryo transfer programme. The relative intensity of
H2O2 concentrations within embryos was measured using
2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence
imaging and DNA fragmentation was observed with transmission electron
microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations
were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/-
SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and
unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed
only in fragmented embryos, and was absent in non-fragmented embryos.
Electron microscopic findings confirmed apoptotic bodies and cytoplasmic
condensation in the fragmented blastomeres. We conclude that there is a
direct relationship between increased H2O2 concentration and apoptosis, and
that further studies should be undertaken to confirm these findings.
相似文献
103.
Michelle lampl Francesca Gotsch Juan Pedro Kusanovic Ricardo Gomez Jyh Kae Nien Edward A. Frongillo Roberto Romero 《American journal of human biology》2010,22(4):431-443
Sex differences in fetal growth have been reported, but how this happens remains to be described. It is unknown if fetal growth rates, a reflection of genetic and environmental factors, express sexually dimorphic sensitivity to the mother herself. This analysis investigated homogeneity of male and female growth responses to maternal height and weight. The study sample included 3,495 uncomplicated singleton pregnancies followed longitudinally. Analytic models regressed fetal and neonatal weight on tertiles of maternal height and weight, and modification by sex was investigated (n = 1,814 males, n = 1,681 females) with birth gestational age, maternal parity, and smoking as covariates. Sex modified the effects of maternal height and weight on fetal growth rates and birth weight. Among boys, tallest maternal height influenced fetal weight growth before 18 gestational weeks of age (P = 0.006), and prepregnancy maternal weight and body mass index subsequently had influence (P < 0.001); this was not found among girls. Additionally, interaction terms between sex, maternal height, and maternal weight identified that males were more sensitive to maternal weight among shorter mothers (P = 0.003) and more responsive to maternal height among lighter mothers (P ≤ 0.03), compared to females. Likewise, neonatal birth weight dimorphism varied by maternal phenotype. A male advantage of 60 g occurred among neonates of the shortest and lightest mothers (P = 0.08), compared to 150 and 191 g among short and heavy mothers, and tall and light‐weight mothers, respectively (P = 0.01). Sex differences in response to maternal size are under‐appreciated sources of variation in fetal growth studies and may reflect differential growth strategies. Am. J. Hum. Biol., 2010. © 2009 Wiley‐Liss, Inc. 相似文献
104.
Su-Feng Chen Shin Nien Chien-Hua Wu Chia-Lin Liu Yun-Ching Chang Yaoh-Shiang Lin 《Journal of the Chinese Medical Association》2013,76(3):146-152
BackgroundDespite increased experience in therapy, the overall outcome of oral squamous cell carcinoma (OSCC) has not improved because of the relative resistance to chemotherapeutic drugs in addition to local invasion and frequent regional lymph node metastases. Quercetin (Qu) is a principal flavonoid compound and an excellent free-radical-scavenging antioxidant that promotes apoptosis. Limited reports regarding the molecular or cellular role of Qu in anticancer properties on OSCC have been presented. This study was conducted to clarify the efficacy of Qu on OSCC in vitro and further to evaluate the possible mechanism(s).MethodsCultured OSCC cells (SCC-25) and human gingival fibroblasts (HGFs) were treated with different concentrations of Qu. Cell viability and cell colony-forming potential were detected with the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) and colony growth assays. Cell-cycle analysis and apoptosis were measured by flow cytometry. Cell migration and invasion were tested using the micropore chamber assay.ResultsCell viability and colony-forming potential were decreased in a dose-dependent manner following Qu treatment. Qu also dose-dependently inhibited the proliferation of SCC-25 cells via both G1 phase cell cycle arrest and mitochondria-mediated apoptosis. In addition, Qu also decreased the abilities of migration and invasion of SCC-25 cells in a dose-dependent manner.ConclusionQu effectively inhibits cell growth and invasion/migration of SCC-25 cells in vitro. The cellular and molecular mechanisms are via cell cycle arrest accompanied by mitochondria-mediated apoptosis. Our findings suggest that Qu may have potential as a new chemopreventive agent or serve as a therapeutic adjuvant for OSCC. 相似文献
105.
HC Korting C Schöllmann 《Journal of the European Academy of Dermatology and Venereology》2009,23(8):876-882
Rosacea is a common, often overlooked, chronic facial dermatosis characterized by intermittent periods of exacerbation and remission. Clinical subtypes and grading of the disease have been defined in the literature. On the basis of a genetic predisposition, there are several intrinsic and extrinsic factors possibly correlating with the phenotypic expression of the disease. Although rosacea cannot be cured, there are several recommended treatment strategies appropriate to control the corresponding symptoms/signs. In addition to adequate skin care, these include topical and systemic medications particularly suitable for the papulopustular subtype of rosacea with moderate to severe intensity. The most commonly used and most established therapeutic regimens are topical metronidazole and topical azelaic acid as well as oral doxycycline. Conventionally, 100–200 mg per day have been used. Today also a controlled release formulation is available, delivering 40 mg per day using non-antibiotic, anti-inflammatory activities of the drug. Anti-inflammatory dose doxycycline in particular allows for a safe and effective short- and long-term therapy of rosacea. Topical metronidazole and topical azelaic acid also appear to be safe and effective for short-term use. There are indications that a combined therapy of anti-inflammatory dose doxycycline and topical metronidazole could possibly have synergy effects. Further interesting therapy options for the short- and long-term therapy of rosacea could be low-dose minocycline and isotretinoin; however, too little data are available with regard to the effectiveness, safety, optimal dosage and appropriate length of treatment for these medications to draw final conclusions.
None declared. 相似文献
Conflicts of interest
None declared. 相似文献
106.
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109.
Liu JM; Chu HC; Chin YH; Chen YM; Hsieh RK; Chiou TJ; Whang-Peng J 《Japanese journal of clinical oncology》1997,27(1):37-41
The aim of this study was to ascertain the prevalence of alternative
medicine consumption in Chinese cancer patients on active conventional
treatment. A cross sectional survey of 100 consecutive advanced cancer
patients admitted to a cancer clinical trial referral unit were personally
interviewed by their assigned oncology research nurse using a specially
designed questionnaire. The results showed that 64% of our patients used
indigenous Chinese medication. In all age groups except the over-70s (P =
0.043), > 50% took such medication, more female (76%) than male (57.6%)
patients (P = 0.323). Patients of all educational levels (P = 0.062) and
religious backgrounds (P = 0.08) consumed alternative medicines. Duration
of alternative medication consumption was less than three months in 50% of
patients, with costs between US$40 and 2000/month for 70% of patients.
Reasons cited for alternative medication consumption was hope that it might
be of some benefit to their well being or disease control, and maybe even
result in a miracle cure. Sources of advice on medication were mostly from
strangers (by word of mouth), family, friends, the media, and infrequently
from qualified professional Chinese doctors. Reasons for discontinuing such
treatment were mostly given as lack of positive effect. In conclusion,
Chinese cancer patients, willingly, rampantly and non-selectively seek out
and consume alternative medications, with almost total ignorance of the
medication consumed, oblivious to any potential side effects, and with
little subjective benefit.
相似文献
110.