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排序方式: 共有9051条查询结果,搜索用时 11 毫秒
71.
Hjördis Högberg Petra Pålsson Fredrik Spak Margareta Larsson Michael B. Wells 《Health & social care in the community》2021,29(6):1896-1914
The aim is to test the reliability of two alcohol screening instruments: (1) The Parent Alcohol Screening Questionnaire (PASQ5), and (2) the Social Support for an Alcohol-free Pregnancy (SSAFP) questionnaire. This is a cohort study from the south of Sweden using repeated surveys during pregnancy. To examine if responses differed according to different data collection methods, two cohorts consisting of 289 expectant mothers and 141 fathers completed the PASQ5 both verbally (weeks 6–7) and in writing (week 12) within regular antenatal visits. One of the cohorts (n = 137/64) also completed the SSAFP in week 12 and later in week 33. The third cohort, consisting of 179 and 133 expectant mothers and fathers, respectively, completed the PASQ5 and the SSAFP twice in late pregnancy (week 31 + 33). Eight of 10 items in the PASQ5 were stable for both expectant mothers and expectant fathers when comparing verbal versus written-delivered formats. Eight of 10 questions in the PASQ5 were stable when assessing the items in a test–retest analysis in late pregnancy for expectant mothers and nine of 10 questions were stable for fathers. The SSAFP items showed high internal consistency (0.86) for expectant mothers and excellent internal consistency (0.94) for expectant fathers. Most SSAFP items (17 of 21 for expectant mothers and 18 of 22 for expectant fathers) were also stable in a test–retest scenario in late pregnancy. Both the PASQ5 and SSAFP are reliable tools and may be helpful for clinicians who aim to have a deeper dialogue about alcohol consumption during pregnancy. These tools may also be helpful for researchers aiming to better understand a person's changes in alcohol intake and/or their social support network. 相似文献
72.
Jana Jedlickova Marie Vajter Tomas Barta Graeme C. M. Black Rahat Perveen Jan Mares Marek Fichtl Bohdan Kousal Lubica Dudakova Petra Liskova 《Clinical genetics》2023,104(4):418-426
Four members of a three-generation Czech family with early-onset chorioretinal dystrophy were shown to be heterozygous carriers of the n.37C>T in MIR204. The identification of this previously reported pathogenic variant confirms the existence of a distinct clinical entity caused by a sequence change in MIR204. Chorioretinal dystrophy was variably associated with iris coloboma, congenital glaucoma, and premature cataracts extending the phenotypic range of the condition. In silico analysis of the n.37C>T variant revealed 713 novel targets. Additionally, four family members were shown to be affected by albinism resulting from biallelic pathogenic OCA2 variants. Haplotype analysis excluded relatedness with the original family reported to harbour the n.37C>T variant in MIR204. Identification of a second independent family confirms the existence of a distinct MIR204-associated clinical entity and suggests that the phenotype may also involve congenital glaucoma. 相似文献
73.
Petra Meier Peter Wiedemann 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1997,235(9):569-574
Background: A small number of eyes with proliferative diabetic retinopathy develop massive central fibrovascular membranes characterized by vitreoretinal tractions along the arcades and optic disk and retinal traction lines extending through the macula. The aim of our study was first to present the results of vitrectomy for removal of these central membranes and second to determine the correlation between preoperative parameters and postoperative visual outcome. Subjects and methods: We treated 28 eyes with severe central fibrovascular diabetic membranes by a modified bimanual en bloc excision technique during vitrectomy. Preoperative examination included general status, visual acuity, slit-lamp investigation, binocular funduscopy, ultrasound investigation and visual evoked potentials (VEP). Further, we analyzed intraoperative complications and postoperative anatomic and functional outcomes. Results: The retinas of 27 eyes with central traction retinal detachments were reattached by surgery. With a minimum of 6 months' follow-up, the macula remained attached in 24 eyes, while the retinas were completely attached in 22 eyes. Preoperative visual acuity was defective light perception to 0.1; an increase in visual acuity to maximal 0.1 was seen in 50% of the patients postoperatively. Preoperative visual acuity of light perception was associated with no functional improvement. Preoperative ultrasound investigation gave information about the real anatomic situation of the retina, especially if funduscopy was not possible. The other preoperative parameters could not predict correctly the functional outcome of vitrectomy in diabetics with severe central fibrovascular membranes because of the damage of the optic nerve and the retina. Conclusions: The high rate of anatomical rettachment after vitrectomy in diabetic eyes with severe central fibrovascular membranes is associated with a slight improvement of function; only preoperative visual acuity of hand motions or better was associated with an improvement of function. 相似文献
74.
Georg Bauer Susanne Kahl Iva Singh Sawhney Petra Hfler Ralph Gerspach Bertfried Matz 《International journal of cancer. Journal international du cancer》1992,51(5):754-760
Studies on the mechanisms of transformation of mammalian cells by herpes simplex virus (HSV) in vitro have been prevented so far by the extremely low transformation frequencies obtained in monolayer culture. Here we present a transformation system that relies on the direct seeding in soft agar of infected single cells, thus avoiding negative interactions between normal and transformed cells. We took advantage of HSV-I temperature-sensitive mutants at the UL9 locus, which codes for a DNA-binding protein necessary for viral DNA replication. At the non-permissive temperature, viral DNA synthesis and late gene expression are prevented. Viral gene expression is restricted to immediate early and early genes. Induction of transformation was highly efficient in our one-step transformation system. It depended on intact viral particles and viral DNA. Immediate early and/or early viral gene expression was sufficient to induce transformation. Colonies were stably transformed and did not show any rescue of viable virus after temperature downshift and co-cultivation with susceptible cells. Transformed cells maintained the transformed state in the absence of viral DNA. Our data therefore support the "hit-and-run" hypothesis for the transforming effect of HSV. 相似文献
75.
Detection of contamination with antineoplastic agents in a hospital pharmacy department 总被引:4,自引:0,他引:4
Paul J. M. Sessink Rob B. Anzion Petra H. H. Van den Broek Rob P. Bos 《Pharmacy World & Science》1992,14(1):16-22
The contamination with fluorouracil, cyclophosphamide and methotrexate was studied in a hospital pharmacy department where these drugs were prepared. In the preparation room, air samples were taken before and during preparation of the drugs. Methotrexate was detected in one sample which was collected during preparation (0.3g/m3). Spot samples were taken in the vertical laminar airflow safety hood before and after preparation of the drugs and after cleaning of the hood. Contamination of the laminar airflow hood was: cyclophosphamide: 1–160 ng/cm2; fluorouracil: 10–62 ng/cm2 and methotrexate: 2–633 ng/cm2. Spot samples from the floor in front of and beneath the laminar airflow hood showed contamination with especially fluorouracil (48–236g/m2). The gloves used during preparation of the drugs were contaminated mainly with fluorouracil (5–980 ng/cm2). Urine samples from two workers involved in the preparation of the drugs were analysed for unmetabolized cyclophosphamide; it was not detected. Although no uptake of cyclophosphamide was established, it is shown that the methods for measurement of cyclophosphamide, fluorouracil and methotrexate in the preparation room are applicable for the control of occupational exposure to these drugs. 相似文献
76.
d,l-Camphor was detected as a new inducer of hydroxylase in the liver musomes of female mice. After a 2-day inhalation of d,l-camphor, cyt. P-450 and the ethylumbelliferone dealkylase were increased by 250 per cent and the NADPH-cyt. P-450 reductase by 350 per cent. The product [NADPH-cyt. P-450 reductase activity × cyt. P450 concentration] was shown to be a suitable reference parameter for the ethylumbelliferone dealkylase activity in the liver musomes during the treatment with four different inducers. The relative dealkylase activity Q was much decreased during inhalation of cyclohexane or d,l-camphor.Obviously these two inducers preferably enhanced cyt. P-450 species with a low dealkylase activity. The Q-values were reproducible. Q was increased by 100 per cent during induction of a MC-sensitive mouse strain with 3-methylcholanthrene, but it was only moderately decreased by induction with phenobarbital. Corresponding to this, methylcholanthrene is known to selectively induce a cyt. P-448 with high dealkylase activity whereas phenobarbital is known to change the hydroxylase specificity in the liver musomes not very much. 相似文献
77.
Musholt TJ Musholt PB Petrich T Oetting G Knapp WH Klempnauer J 《World journal of surgery》2000,24(11):1409-1417
Hereditable predisposition to papillary thyroid carcinoma (PTC) and multinodular goiter (MNG) without evidence of an association
with other malignancies as a distinct entity was recognized only recently. A meta-review of the literature on familial PTC
(FPTC) was undertaken, and characteristics of families with frequent occurrence of PTC or MNG (or both) were summarized. A
database on thyroid cancer patients maintained in our institution was searched for potential FPTC families. Clinical examinations
were performed in 6 of 12 Hannover kindreds identified, and blood samples of all family members were collected for genetic
analyses. Clinical presentations and histopathologic features of the FPTC cases were compiled. Based on the FPTC meta-review
and own experience, predictive criteria to identify families at risk were developed: Exclusion criteria were previous radiation
exposure and coincidence with neoplasia syndromes. Primary criteria for susceptibility to FPTC are (1) PTC in two or more
first-degree relatives and (2) MNG in at least three first- or second-degree relatives of a PTC patient. Secondary criteria
are diagnosis in a patient younger than 33 years, multifocal or bilateral PTC, organ-exceeding tumor growth (T4), metastasis
(N1, M1), and familial accumulation of adolescent-onset thyroid disease. A hereditary predisposition to PTC is considered
if both primary criteria or one primary criterion plus three secondary criteria are present. Family history-taking is recommended
for all PTC patients to identify FPTC kindreds at risk. Blood relatives of FPTC index patients who harbor MNG should undergo
thorough and regular clinical screening. Suspicious lesions should prompt early surgical intervention. 相似文献
78.
Stefan Holdenrieder Jutta Stief Albrecht Bergner Fernando Gamarra Anke Mitlewski Dorothea Nagel Rudolph M Huber Petra Stieber 《Tumour biology》2004,25(5-6):321-326
Nucleosomes, which are typical cell death products, are elevated in the serum of cancer patients and are known to rapidly increase during radiotherapy. As both normal and malignant cells are damaged by irradiation, we investigated to which extent both cell types contribute to the release of nucleosomes. We cultured monolayers of normal bronchoepithelial lung cells (BEAS-2B, n = 18) and epithelial lung cancer cells (EPLC, n = 18), exposed them to various radiation doses (0, 10 and 30 Gy) and observed them for 5 days. Culture medium was changed every 24 h. Subsequently, nucleosomes were determined in the supernatant by the Cell Death Detection-ELISA(plus) (Roche Diagnostics). Additionally, the cell number was estimated after harvesting the cells in a second preparation. After 5 days, the cell number of BEAS-2B cultures in the irradiated groups (10 Gy: median 0.03 x 10(6) cells/culture, range 0.02-0.08 x 10(6) cells/culture; 30 Gy: median 0.08 x 10(6) cells/culture, range 0.02-0.14 x 10(6) cells/culture) decreased significantly (10 Gy: p = 0.005; 30 Gy p = 0.005; Wilcoxon test) compared to the non-irradiated control group (median 4.81 x 10(6) cells/culture, range 1.50-9.54 x 10(6) cells/culture). Consistently, nucleosomes remained low in the supernatant of non-irradiated BEAS-2B. However, at 10 Gy, BEAS-2B showed a considerably increasing release of nucleosomes, with a maximum at 72 h (before irradiation: 0.24 x 10(3) arbitrary units, AU, range 0.13-4.09 x 10(3) AU, and after 72 h: 1.94 x 10(3) AU, range 0.11-5.70 x 10(3) AU). At 30 Gy, the release was even stronger, reaching the maximum earlier (at 48 h, 11.09 x 10(3) AU, range 6.89-18.28 x 10(3) AU). In non-irradiated EPLC, nucleosomes constantly increased slightly. At 10 Gy, we observed a considerably higher release of nucleosomes in EPLC, with a maximum at 72 h (before irradiation: 2.79 x 10(3) AU, range 2.42-3.80 x 10(3) AU, and after 72 h: 7.16 x 10(3) AU, range 4.30-16.20 x 10(3) AU), which was more than 3.5 times higher than in BEAS-2B. At 30 Gy, the maximum (6.22 x 10(3) AU, range 5.13-9.71 x 10(3) AU) was observed already after 24 h. These results indicate that normal bronchoepithelial and malignant lung cancer cells contribute to the release of nucleosomes during irradiation in a dose- and time-dependent manner with cancer cells having a stronger impact at low doses. 相似文献
79.
Petra Heinm?ller Christof Gross Kurt Beyser Claudia Schmidtgen Gerd Maass Michele Pedrocchi Josef Rüschoff 《Clinical cancer research》2003,9(14):5238-5243
PURPOSE: For the first time a large number (563) of non-small cell lung cancer (NSCLC) samples was used to compare three different technologies for the assessment of HER2 status. Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) were used for tumor tissue samples, and ELISA for serum samples. The results were compared with other tumor entities, mainly breast. EXPERIMENTAL DESIGN: Samples (563) from patients suffering from primary advanced or metastatic NSCLC were evaluated. RESULTS: HER2 overexpression was demonstrated using IHC in 20% (83 of 410) of the specimens, whereas 2% (7 of 378) were positive by FISH and 6% (31 of 511) showed elevated serum HER2 levels (>15 ng/ml) by ELISA. Sixty-six specimens were positive by IHC only and 13 by ELISA only, whereas none of the specimens was positive only by FISH. Concordance between all of the techniques was seen for only 3 specimens. Of 7 IHC 3+ specimens, 4 showed gene amplification by FISH, and 3 were positive by ELISA (>15 ng/ml), whereas of 76 IHC 2+ cases only 2 were amplified by FISH, and 4 were positive by ELISA. HER2 positivity by at least one of the three techniques was most common in adenocarcinomas, at 29% (42 of 143). CONCLUSION: Gene amplification and HER2 protein overexpression at the 3+ level appear to be uncommon in NSCLC. The concordance between FISH and IHC 3+ disease was good in this study, in addition, ELISA would have detected several patients without IHC/FISH-positive disease. 相似文献
80.
Angiogenesis in Vulvar Intraepithelial Neoplasia 总被引:1,自引:0,他引:1
Dagmar Bancher-Todesca M.D. Andreas Obermair M.D. Selcuk Bilgi M.D. Petra Kohlberger M.D. Christian Kainz M.D. Gerhard Breitenecker M.D. Sepp Leodolter M.D. Gerald Gitsch M.D. 《Gynecologic oncology》1997,64(3):496-500
Vulvar intraepithelial neoplasia (VIN) has been reported to be a precursor of invasive vulvar cancer. Switching to the angiogenic phenotype is considered a key step in tumor growth. Microvessel density (MVD) and vascular endothelial growth factor (VEGF), a highly angiogenic peptide, are important parameters of tumor angiogenesis. Forty-three histologic slides with 38 VIN I–III lesions were immunohistochemically stained for factor VIII-related antigen (F8-RA) and 44 slides with 37 VIN I–III for VEGF, since F8-RA reliably highlights tumor microvessels. Determination of MVD and VEGF expression was done by counting microvessels and VEGF-positive cells at a magnification of 200× and 400×. The highest concentration of F8-RA-stained MVD and VEGF expression was found at a small subepithelial area at the border of the VIN lesion to the stroma underneath but concentrations were low in all specimens of normal epithelium. High VEGF expression was significantly correlated to high MVD. For both MVD and VEGF expression the differences between VIN I and VIN III and between VIN II and VIN III were statistically significant (P< 0.0001). VIN III lesions are the clinical relevant precursors of invasive cancer of the vulva, as outlined by intense expression of VEGF protein and a highly dense network of microvessels underlying the dysplastic epithelium. 相似文献