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排序方式: 共有1758条查询结果,搜索用时 62 毫秒
31.
Morphometric study of histological changes in sublabial salivary glands due to aging process. 总被引:2,自引:0,他引:2
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P C De Wilde J P Baak J C van Houwelingen L Kater P J Slootweg 《Journal of clinical pathology》1986,39(4):406-417
The sublabial salivary glands were studied by morphometric methods in 68 healthy volunteers to establish possible changes related to age in those tissue components that are affected in Sjögren''s syndrome and connective tissue diseases (and which might stimulate Sjögren''s syndrome). There was an increase in the amount of connective tissue and intralobular ducts with age and a corresponding decrease in acinar tissue. During the aging process changes in the intralobular ducts occurred: the outer and inner diameters of these ducts and the thickness of the epithelium decreased, but the ratio of the outer and inner diameters of the ducts remained constant. The amount of diffuse lymphoplasmacytic infiltrate and the vascularity of the tissue remains constant with age. In 15 of the subjects, however, discrete lymphocytic foci were seen and in six of these more than one focus/4 mm2 of salivary tissue was found, which has been described as suggestive of Sjögren''s syndrome. The volume percentage of lymphocytic foci is constant during the aging process. The histological features commonly used to diagnose Sjögren''s syndrome may occur in normal people, and false positive diagnoses will occur if these criteria are rigidly adhered to. Morphometry may provide more reliable criteria for distinguishing changes induced by inflammation and related to age which occur in salivary tissue. 相似文献
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34.
Morphometric data to FIGO stage and histological type and grade for prognosis of ovarian tumours. 总被引:2,自引:1,他引:2
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J P Baak E C Wisse-Brekelmans F A Langley A Talerman J F Delemarre 《Journal of clinical pathology》1986,39(12):1340-1346
The prognostic value of using histological typing, grading, and morphology, in addition to clinical staging, was assessed in 98 cases of invasive ovarian cancer of the common epithelial types (serous, mucinous, and endometrial). All of these cases had at least five years of follow up. When regression analysis was used, the International Federation of Gynaecology and Obstetrics' (FIGO) staging system was the best indicator for prognosis. Analysis of a combination of morphometric features was the second best indicator, being especially useful for the those patients with stage I disease. Variables that indicated a relatively poor prognostic outcome were mitotic index above 30; volume percentage epithelium above 65%; shortest nuclear axis above a mean of 1 X 1 micrometers. Histological typing of ovarian tumours was of limited value; mucinous tumours have a somewhat better prognosis than serous tumours, but the prognostic value of typing alone was found to be limited. Qualitative histological grading was useful, but the prognostic value of morphometric grading was better. Measurement of morphological features with an interactive computer program is simple and can be done by a pathologist or a technician: in future it is likely that such automated systems of measurement will improve the objectivity of tissue analysis. 相似文献
35.
Progression from colorectal adenoma to carcinoma is associated with non-random chromosomal gains as detected by comparative genomic hybridisation 总被引:6,自引:0,他引:6
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Meijer GA Hermsen MA Baak JP van Diest PJ Meuwissen SG Beliën JA Hoovers JM Joenje H Snijders PJ Walboomers JM 《Journal of clinical pathology》1998,51(12):901-909
AIMS: Chromosomal gains and losses were surveyed by comparative genomic hybridisation (CGH) in a series of colorectal adenomas and carcinomas, in search of high risk genomic changes involved in colorectal carcinogenesis. METHODS: Nine colorectal adenomas and 14 carcinomas were analysed by CGH, and DNA ploidy was assessed with both flow and image cytometry. RESULTS: In the nine adenomas analysed, an average of 6.6 (range 1 to 11) chromosomal aberrations were identified. In the 14 carcinomas an average of 11.9 (range 5 to 17) events were found per tumour. In the adenomas the number of gains and losses was in balance (3.6 v 3.0) while in carcinomas gains occurred more often than losses (8.2 v 3.7). Frequent gains involved 13q, 7p, 8q, and 20q, whereas losses most often occurred at 18q, 4q, and 8p. Gains of 13q, 8q, and 20q, and loss of 18q occurred more often in carcinomas than in adenomas (p = 0.005, p = 0.05, p = 0.05, and p = 0.02, respectively). Aneuploid tumours showed more gains than losses (mean 9.3 v 4.9, p = 0.02), in contrast to diploid tumours where gains and losses were nearly balanced (mean 3.1 v 4.1, p = 0.5). CONCLUSIONS: The most striking difference between chromosomal aberrations in colorectal adenomas and carcinomas, as detected by CGH, is an increased number of chromosomal gains that show a nonrandom distribution. Gains of 13q and also of 20q and 8q seem especially to be involved in the progression of adenomas to carcinomas, possibly owing to low level overexpression of oncogenes at these loci. 相似文献
36.
Monitoring serum CEA in women with primary breast tumours positive for oestrogen receptor and with spread to lymph nodes.
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J C van der Linden J P Baak T Postma J Lindeman C J Meyer 《Journal of clinical pathology》1985,38(11):1229-1234
Serum carcinoembryonic antigen concentrations (serum CEA) in 80 patients with primary breast cancer were measured preoperatively, one month after operation, and thereafter serially every third month. These data were related to histological and morphometric features of the primary breast carcinoma and the lymph node metastases and to clinical follow up data. Analysis of the serum CEA values showed significant correlations with size of tumour, the presence of lymph node metastases, oestrogen receptor, and occurrence of distant metastases. Furthermore, the results indicated that serial determination of serum CEA in the first two years after operation may be useful in monitoring for the occurrence of distant metastases in patients with metastatic spread to lymph nodes and with large (greater than or equal to 2 cm) primary breast tumours positive for oestrogen receptor. In agreement with other studies, however, it was found that the predictive value of serum CEA concentrations in general is weak and costs may prohibit the implementation of the routine assessment of CEA concentrations. 相似文献
37.
JJ Favre Ph Chaffanjon JG Passagia JP Chirossel 《Surgical and radiologic anatomy : SRA》1995,17(2):133-138
Summary The authors report the results of a series of dissections and anatomic sections of the fronto-basal region of the brain and of the anterior cranial fossa in human cadavers. The constant presence of an arachnoidal cistern above the olfactory nerve was verified. The arachnoid separates from the pial membrane and forms a bridge with the ventral part of the olfactory bulb and tract, from the lateral edge of the olfactory sulcus to the medial edge of the gyrus rectus. The cistern is wide in its anterior portion, between the gyrus rectus and the olfactory bulb, and is reduced to a virtual slit in its posterior portion where the tract is lodged in the olfactory sulcus. The olfactory nerve can be separated without damaging fronto-basal arachnoidial adhesions over several centimeters. Dissection of this region after intravascular injection of colored media shows the constant presence of an artery destined to the olfactory bulb and tract. It originates either from the lateral surface of the anterior cerebral a. (segment A2), or from the medial fronto-basal a., and consistently provides terminal branches in front of the olfactory trigone in the medial olfactory sulcus. At their ventral extremity, the olfactory structures are therefore vascularised independently for several centimeters, from the lower face of the frontal lobe. The independent vascularisation of the olfactory nerve, the tenuous and easily detachable adhesions, and the actual presence of a true arachnoidal cistern all contribute to enabling surgical techniques which conserve olfactory function during anterior approaches.
Vascularisation du nerf olfactif. Rapports méningés et applications chirurgicales
Résumé Les auteurs rapportent les résultats d'une série de dissections et de coupes de la région fronto-basale de l'encéphale et de la fosse crânienne antérieure sur sujets cadavériques. La présence constante d'une citerne arachnoïdienne au dessus du n. olfactif a été vérifiée. L'arachnoïde se sépare du feuillet pial et passe en pont à la partie ventrale du bulbe et du tractus olfactifs, du bord latéral du sillon olfactif au bord médial du gyrus rectus. La citerne est large dans sa portion antérieure, entre le gyrus rectus et le bulbe olfactif, se réduit à une fente virtuelle postérieure lorsque le tractus se loge dans le sillon olfactif. Le n. olfactif peut être séparé sans dommage des adhérences arachnoïdiennes fronto-basales sur quelques centimètres. La dissection de cette région, après injection intravasculaire de masses colorées montre, de façon originale, la présence constante d'une artère destinée au tractus et au bulbe olfactifs. Elle naît soit de la face latérale de l'a. cérébrale antérieure (segment A2), soit de l'a. fronto-basale médiale, pour donner ses branches terminales toujours en avant du trigone olfactif dans le sillon orbitaire médial. Sur quelques centimètres à leur extrémité ventrale, les structures olfactives ont donc une vascularisation indépendante de la face inférieure du lobe frontal. L'indépendance vasculaire du n. olfactif, des adhérences ténues, facilement détachables, et la réalité vérifiée d'une véritable citerne arachnoïdienne permettent d'imaginer des techniques conservatrices de la fonction olfactive utilisées dans plusieurs indications de la chirurgie de la fosse crânienne antérieure.相似文献
38.
The GAP-related domain of tuberin, the product of the TSC2 gene, is a target for missense mutations in tuberous sclerosis 总被引:5,自引:0,他引:5
Maheshwar MM; Cheadle JP; Jones AC; Myring J; Fryer AE; Harris PC; Sampson JR 《Human molecular genetics》1997,6(11):1991-1996
Tuberous sclerosis is an autosomal dominant trait in which the
dysregulation of cellular proliferation and differentiation results in the
development of hamartomatous growths in many organs. The TSC2 gene is one
of two genes determining tuberous sclerosis. Inactivating germline
mutations of TSC2 in patients with tuberous sclerosis and somatic loss of
heterozygosity at the TSC2 locus in the associated hamartomas indicate that
TSC2 functions as a tumour suppressor gene and that loss of function is
critical to expression of the tuberous sclerosis phenotype. The TSC2
product, tuberin, has a region of homology with the GTPase activating
protein rap1GAP and stimulates the GTPase activity of rap1a and rab5a in
vitro. Here we show that the region of homology between tuberin and human
rap1GAP and the murine GAP mSpa1 is more extensive than previously reported
and spans approximately 160 amino acid residues encoded within exons 34-38
of the TSC2 gene. Single strand conformation polymorphism analysis of these
exons in 173 unrelated patients with tuberous sclerosis and direct
sequencing of variant conformers together with study of additional family
members enabled characterisation of disease associated mutations in 14
cases. Missense mutations, which occurred in exons 36, 37 and 38 were
identified in eight cases, four of whom shared the same recurrent change
P1675L. Each of the five different missense mutations identified was shown
to occur de novo in at least one sporadic case of tuberous sclerosis. The
high proportion of missense mutations detected in the region of the TSC2
gene encoding the GAP-related domain supports its key role in the
regulation of cellular growth.
相似文献
39.
Assisted reproductive technology and complex chromosomal rearrangements: the limits of ICSI 总被引:4,自引:0,他引:4
Siffroi JP; Benzacken B; Straub B; Le Bourhis C; North MO; Curotti G; Bellec V; Alvarez S; Dadoune JP 《Molecular human reproduction》1997,3(10):847-851
Complex chromosomal rearrangements are very rare events in the human
population. According to our knowledge on the consequences of simple
reciprocal translocations for male fertility, translocations involving
three or more chromosomes are thought to lead to severe reproductive
impairments in terms of meiotic disturbance or chromosomal imbalance of
gametes. We report the case of a 48 year old man whose sperm count revealed
either oligozoospermia (<10(3) spermatozoa/ml) or azoospermia. He was
referred to the laboratory for in-vitro fertilization after
intracytoplasmic sperm injection. Cytogenetic investigations showed a
complex chromosomal rearrangement involving firstly a translocation between
the short arm of chromosome 7 and the long arm of chromosome 13 and
secondly a translocation between the short arm of the same chromosome 13
and the short arm of chromosome 9. Diagnosis was ascertained by
fluorescence in-situ hybridization and staining of the nucleolar organizer
regions. Theoretical study of the translocated chromosomes predicted a
'chain' configuration of the hexavalent at the pachytene stage of meiosis.
In all, 32 modes of segregation were considered and only one resulted
either in a normal or a balanced gamete karyotype. Genetic counselling and
choice of appropriate artificial reproduction technique are discussed.
相似文献
40.
Conclusion The opening of the anal canal appears to be the factor which initiated the differentiation of the sphincter apparatus.The internal sphincter m. of the anus is entirely composed of smooth muscle as distinct from the striated fibers of the m. puborectalis, and the external sphincter which is a mixture of smooth and striated fibers (of skeletal type). It develops in the terminal part of the internal circular layer of the rectal m., outside which are longitudinal fibers which descend early to form the external sphincter (beginning around the third month).This study shows that the internal sphincter is scarcely evident before 12 SA. Thus continence between 10 and 12 SA (after the closure of the anal membrane) is closely related to the other components of the sphincter apparatus. On the other hand, the internal sphincter has become well formed after 28 to 30 SA and then plays a direct role in maintaining continence. 相似文献