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1.
2.
Ultrastructure of the early human implantation in vitro 总被引:1,自引:1,他引:1
Lindenberg Svend; Hyttel Poul; Lenz Sunzan; Holmes Poul V. 《Human reproduction (Oxford, England)》1986,1(8):533-538
Four hatched human blastocysts obtained after in-vitro fertilizationand development were placed on monolayer cell cultures of humanendometrial epithelium, and subsequently examined by transmissionelectron microscopy. All four blastocysts became adherent tothe monolayer and three implanted and exhibited outgrowth oftheir trophoblastic cells. During implantation the blastocystsdifferentiated into mural and polar trophoblastic cells, andembryonic cells including endodermal cells. The endometrialcells were displaced and stacked into a multilayer at the peripheryof the implantation sites, allowing the trophoblastic cellsto come in contact with the culture dish. The endometrial cellsdisplayed local exo- or endo-cytosis where they contacted thetrophoblastic cells. The trophoblastic cells were not observedto be phagocytosing endometrial cells. These observations suggestthat human blastocysts portray an intrusive type of implantationduring the initial stages. 相似文献
3.
4.
Histopathological grading of soft tissue tumours. Prognostic significance in a prospective study of 278 consecutive cases 总被引:1,自引:0,他引:1
Olaf Myhre Jensen Jrgen Hgh Svend E.
stgaard Axel Munck Nordentoft Otto Sneppen 《The Journal of pathology》1991,163(1):19-24
A consecutive 10-year series of 278 soft tissue sarcomas was prospectively graded, using a system based on the number of mitoses and taking into account parameters such as cellularity, anaplasia, necrosis, and histogenetic type and subtype of tumour. Prognostic factors in relation to metastasis-free survival were studied by uni- and multivariate analysis. Fifty-seven (20.5 per cent) were low-grade tumours, 43 (15.5 per cent) were intermediate, and 178 (64 per cent) were high grade. High-grade tumours were divided into two groups; 80 (29 per cent) grade 3A (= 5-20 mitoses per 10 high power fields (HPF)) and 78 grade 3B (28 per cent) (= more than 20 mitoses/10 HPF); 10 HPF corresponds to 2.5 mm2. Twenty (7.2 per cent) high-grade tumours could not be further subdivided. Grading was found to be the prognostic factor associated with the strongest predictive value. Five-year survival in low-grade and intermediate tumours (95 and 86 percent, respectively) differed significantly (P less than 0.0001) from high grade (50 per cent) and (p = 0.0018) between grade 3A (64 per cent) and grade 3B (41 per cent). Other prognostic indicators of importance in high-grade tumours were age, local recurrence at presentation (primary operation outside the Centre), and localization (superficial vs. deep). 相似文献
5.
Svend Davanger Jon Storm-Mathisen Ole Petter Ottersen 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1994,98(2):342-354
Human retinae from surgical specimens rapidly fixed in a glutaraldehyde/formaldehyde mixture were subjected to postembedding, immunogold immunocytochemistry of glutamate and glycine, and subsequently analysed in an electron microscope. The two amino acids were visualised in the same tissue sections by the use of two different gold particle sizes. All bipolar cell perikarya and terminals showed significant glutamate labelling with mean gold particle densities 3–4 times higher than those of the retinal, non-neural pigment epithelial and Müller cells. Bipolar cell terminals displayed significantly higher glutamate labelling density than the bipolar cell bodies, as would be expected of glutamatergic neurons. A subpopulation of the glutamate-immunolabelled bipolar cell bodies (18%) and terminals (32%) also exhibited strong glycine labelling (7–8 times that of pigment epithelial and Müller cells). These glutamate-glycine positive terminals established contacts with amacrine cell processes and ganglion cell dendrites and were localised almost exclusively at between 44% and 88% depth of the inner plexiform layer, indicating that they belong to the ON cone bipolar system. This subpopulation of terminals was endowed with significantly higher glycine labelling density than the glycine positive bipolar cell bodies. These results show that human bipolar cell terminals colocalise glutamate and glycine and provide the first direct demonstration of an enrichment of these two amino acids in the same presynaptic element. 相似文献
6.
Classification of anti-FcepsilonRI and anti-IgE autoantibodies in chronic idiopathic urticaria and correlation with disease severity 总被引:5,自引:0,他引:5
Sabroe RA Fiebiger E Francis DM Maurer D Seed PT Grattan CE Black AK Stingl G Greaves MW Barr RM 《The Journal of allergy and clinical immunology》2002,110(3):492-499
BACKGROUND: Circulating autoantibodies against FcepsilonRI, IgE, or both occur in approximately one third of patients with chronic idiopathic urticaria (CIU), but not all autoantibodies initiate histamine release. OBJECTIVE: We sought to classify patients with CIU into subsets on the basis of serum bioactivity and immunoreactivity and to examine the relationship between newly defined subtype and disease severity. METHODS: Sera from patients with CIU (n = 78), dermog-raphism (n = 15), and cholinergic urticaria (n = 10) and sera from healthy subjects (n = 39) were analyzed by means of Western blot analysis for anti-FcepsilonRI autoantibodies and for histamine release from basophils and dermal mast cells. In vivo reactivity of autologous serum was tested by means of intradermal injection, and CIU severity was determined on the basis of clinical interview. RESULTS: We classified sera from patients with CIU into 5 subsets: immunoreactive histamine-releasing anti-FcepsilonRI autoantibodies (n = 20 [26%]); immunoreactive anti-FcepsilonRI autoantibodies without histamine-releasing activity (n = 12 [15%]); anti-IgE-like autoantibodies (n = 7 [9%]); serum containing a mast cell-specific histamine-releasing factor (n = 7 [9%]); and sera with no identifiable factor (n = 32 [41%]). Patients with serum histamine-releasing activity had more severe urticaria than patients without such activity. Positive skin test responses to autologous sera were associated with histamine-releasing anti-FcepsilonRI autoantibodies but not with non-histamine-releasing anti-FcepsilonRI autoantibodies. Neither healthy subjects nor patients with dermographism or cholinergic urticaria had his-tamine-releasing anti-FcepsilonRI autoantibodies. CONCLUSION: These data support the specificity of functional anti-FcepsilonRI autoantibodies to CIU. The identification of distinctive subsets of patients suggests that other pathogenic mechanisms occur in CIU in addition to direct ligation of FcepsilonRI by autoantibodies causing dermal mast cell degranulation. Elucidating these mechanisms might lead to new treatments for CIU. 相似文献
7.
Wang D Braendstrup O Larsen S Horn T Strandgaard S 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2004,112(6):358-368
Nitric oxide (NO) influences tubular fluid and electrolyte transport, and hence possibly also fluid accumulation in renal cysts. The expression and activity of intrarenal constitutive NO synthase (cNOS) [neuronal NOS, nNOS and endothelial NOS, eNOS] and inducible NOS (iNOS) and plasma nitrite/nitrate (PNOx) concentration were assessed in homozygous Han:SPRD polycystic kidney disease (PKD) rats (cy/cy), heterozygous Han:SPRD PKD rats (cy/+), homozygous normal Han:SPRD littermates (+/+) and Sprague Dawley rats (sd). The results showed: 1) nNOS expression was decreased in proximal tubules and thick ascending limbs of the loop of Henle in cy/cy and cy/+ rats compared to +/+ and sd rats (p<0.05). nNOS was weakly expressed in the epithelium of small cysts and unexpressed in epithelium of large cysts. 2) iNOS expression was increased in proximal tubular epithelial cells in cy/+ rats compared to +/+ rats and sd rats (p<0.01). iNOS expression in cyst epithelium was decreased in cy/+ rats (p<0.05) and absent in cy/cy rats. 3) eNOS expression was similar in the endothelium of intrarenal arteries in all groups. 4) The activity of renal cNOS was decreased in cy/cy and cy/+ rats; the activity of iNOS was decreased only in cy/cy rats, with no significant difference among the other three groups. 5) PNOx concentration was higher in cy/cy rats than in the other three groups, and correlated positively with plasma creatinine and urea. In conclusion, NOS expression and activity decreased as cysts developed, suggesting that NO downregulation is involved in the pathogenesis of PKD. 相似文献
8.
Thy Thy Vanem Tordis Böker Gunhild F. Sandvik Eva Kirkhus Hans‐Jørgen Smith Kai Andersen Liv Drolsum Rigmor Lundby Cecilie Røe Kirsten Krohg‐Sørensen Odd R. Geiran Benedicte Paus Svend Rand‐Hendriksen 《American journal of medical genetics. Part A》2020,182(2):397-408
The age‐dependent penetrance of organ manifestations in Marfan syndrome (MFS) is not known. The aims of this follow‐up study were to explore how clinical features change over a 10‐year period in the same Norwegian MFS cohort. In 2003–2004, we investigated 105 adults for all manifestations in the 1996 Ghent nosology. Ten years later, we performed follow‐up investigations of the survivors (n = 48) who consented. Forty‐six fulfilled the revised Ghent criteria. Median age: females 51 years, range 32–80 years; males 45 years, range 30–67 years. New aortic root dilatation was detected in patients up to 70 years. Ascending aortic pathology was diagnosed in 93 versus 72% at baseline. Sixty‐five percent had undergone aortic surgery compared to 39% at baseline. Pulmonary trunk mean diameter had increased significantly compared to baseline. From inclusion to follow‐up, two patients (three eyes) developed ectopia lentis, four developed dural ectasia, four developed scoliosis, three developed incisional or recurrent herniae, and 14 developed hindfoot deformity. No changes were found regarding protrusio acetabuli, spontaneous pneumothorax, or striae atrophicae. The study confirms that knowledge of incidence and progression of organ manifestations throughout life is important for diagnosis, treatment, and follow‐up of patients with verified or suspected MFS. 相似文献
9.
The aim of this present study was to compare the use by smokers and non-smokers of pamphlets about smoking as delivered from different settings. The study was a nation-wide cross-sectional survey of 1924 randomly selected, Danish men and women, aged 14–77 y, who had answered a mailed questionnaire in 1994. Of these 71% also participated in a telephone interview enquiring about the use of health education material, smoking status and socio-demographic variables, 39% of readers of household-delivered anti-smoking pamphlets reported having gained information from them and 22% reported having made changes in their own smoking behaviour such as avoiding smoking in the presence of non-smokers. In general practice settings, these percentages were higher among smokers. Smokers who were thinking of stopping smoking in the near future were in addition more likely to take and to read smoking related health education materials from other places. Non-smokers received (3–49%) and read pamphlets about smoking as frequently as did smokers who did not intend to quit. In conclusion, written health education material was well received by readers, but, when distributed in a more open setting it needs to be targeted towards smokers who are considering stopping smoking. In general practice, smokers not thinking of stopping were open to health education, and pamphlets used in this setting should also target this group. Non-smokers contribute indirectly to smokers quitting by providing support to smokers and pamphlets for non-smokers need to be more targeted towards this social role. 相似文献
10.
Strandgaard S 《The American journal of geriatric cardiology》1993,2(6):32-36
Cerebral blood flow (CBF) and cerebral metabolic activity tend to decrease in old age. The effect of age per se on the regulation of CBF is not readily separated from the effect of age-associated diseases such as atherosclerosis, multi-infarct dementia, and diabetes mellitus, which may lead to an impairment of CBF autoregulation. Stroke may be prevented effectively by antihypertensive treatment in otherwise healthy elderly patients, but care should be taken to prevent overtreatment with consequent cerebral ischemia. The risk of this may be especially great in elderly patients with hypertension who have postural hypotension. 相似文献