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11.
12.
The mean maximum nuclear diameter (Dmax) in 21 cases of non-Hodgkin's lymphoma (NHL) has been determined, using the Reichert-Jung (Kontron) MOP-AMO3 user-controlled image analyser. Nuclear diameters of high-grade malignancy NHL were found to be considerably greater than those of low-grade malignancy lymphomas, although there was some overlap of their ranges. These findings confirm objectively subjective estimates of nuclear size in NHL. The relative usefulness of the user-controlled (interactive) image analyser for the measurement of nuclei in tissue sections is compared with that of a fully automatic machine. 相似文献
13.
Preliminary report of an ultrasonography and colour Doppler uterine score to predict uterine receptivity in an in-vitro fertilization programme 总被引:1,自引:4,他引:1
Salle B; Bied-Damon V; Benchaib M; Desperes S; Gaucherand P; Rudigoz RC 《Human reproduction (Oxford, England)》1998,13(6):1669-1673
A total of 96 women undergoing in-vitro fertilization (IVF) treatment were
examined by transvaginal ultrasonography with colour and pulsed Doppler
ultrasound on the 22nd day of the menstrual cycle preceding IVF. We
assessed endometrial thickness, endometrial morphology, myometrial
echogenicity, subendometrial vascularization, the uterine artery
pulsatility index, protodiastolic notch and end diastolic blood flow in
order to define a uterine score which could be correlated with the
pregnancy rate. The overall pregnancy rate was 30.2%, and there was no
difference between the pregnant and non-pregnant groups with regard to any
of the ultrasonographic and Doppler parameters when examined separately.
However, the uterine score was significantly higher in the pregnant group
(15.9 +/- 2.81 versus 12.7 +/- 5.3, P = 0.002; t-test). No pregnancy
occurred if the score was between 0 and 10. With a score of 11-15 there was
a 34.7% chance of pregnancy, and scores >16 had a 42% chance of
pregnancy. In conclusion, individual ultrasonographic and Doppler
parameters are not of sufficient accuracy to predict uterine receptivity.
The uterine score calculated prior to IVF cycles appears to be a useful
predictor of implantation.
相似文献
14.
Yanni Li Lianne M. Nieuwenhuis Michiel D. Voskuil Ranko Gacesa Shixian Hu Bernadien H. Jansen Werna T. U. Venema Bouke G. Hepkema Hans Blokzijl Henkjan J. Verkade Ton Lisman Rinse K. Weersma Robert J. Porte Eleonora A. M. Festen Vincent E. de Meijer 《American journal of transplantation》2021,21(9):3133-3147
Thrombosis after liver transplantation substantially impairs graft- and patient survival. Inevitably, heritable disorders of coagulation originating in the donor liver are transmitted by transplantation. We hypothesized that genetic variants in donor thrombophilia genes are associated with increased risk of posttransplant thrombosis. We genotyped 775 donors for adult recipients and 310 donors for pediatric recipients transplanted between 1993 and 2018. We determined the association between known donor thrombophilia gene variants and recipient posttransplant thrombosis. In addition, we performed a genome-wide association study (GWAS) and meta-analyzed 1085 liver transplantations. In our donor cohort, known thrombosis risk loci were not associated with posttransplant thrombosis, suggesting that it is unnecessary to exclude liver donors based on thrombosis-susceptible polymorphisms. By performing a meta-GWAS from children and adults, we identified 280 variants in 55 loci at suggestive genetic significance threshold. Downstream prioritization strategies identified biologically plausible candidate genes, among which were AK4 (rs11208611-T, p = 4.22 × 10−05) which encodes a protein that regulates cellular ATP levels and concurrent activation of AMPK and mTOR, and RGS5 (rs10917696-C, p = 2.62 × 10−05) which is involved in vascular development. We provide evidence that common genetic variants in the donor, but not previously known thrombophilia-related variants, are associated with increased risk of thrombosis after liver transplantation. 相似文献
15.
RAJVIR BHALWAR HS SANDHU RC AHUJA GK SINGH RP MISRA 《Medical Journal Armed Forces India》1994,50(3):175-180
A population based hybrid design combining element of cohort and cross-sectional approach was used to develop a simple clinical algorithm to predict individual probability of developing hypertension (systolic BP > 140 mm Hg and/or diastolic BP > 90 mmHg). 3615 soldiers initially normotensive at the time of induction into high altitude, were studied by systematic random sampling. Multiple logistic regression analysis showed a high significant association between hypertension and age, body mass index (BMI), tobacco smoking and alcohol consumption. Using the constant/coefficient values obtained from the logistic model and the receiver operating characteristics (ROC) curve analysis, the following predictive rule was developed – To the age in years, add (BMIx 3.86); also add 5.53 if he is a smoker; and add 19.81 if he consumes alcohol. If the total exceeds 142, the individual is at high risk of developing hypertension. This algorithm carries a sensitivity of 68.2% and specificity of 78.5%.KEY WORDS: Hypertension, High altitude 相似文献
16.
A 3 year old Turkish girl is described who was suffering from major histocompatibility complex (MHC) class II deficiency syndrome, which is characterised by the lack of expression of HLA class II antigens on mononuclear cells. The presence of HLA class II genes was demonstrable at the DNA level. Combined immunodeficiency was indicated by hypogammaglobulinaemia and the absence of delayed type hypersensitivity on skin testing. Further, she was unable to produce specific antibodies towards foreign antigens and suffered from recurrent pulmonary, gastrointestinal, and septic infections from the third month of life. The clinical course was complicated by a Coombs test positive haemolytic anaemia due to the production of autoantibodies against the rhesus "e' antigen, a non-glycosylated protein antigen. Haemolysis could be controlled by oral steroid treatment. This case is of interest as it shows that despite the absence of HLA class II antigens and combined immunodeficiency autoimmune reactions with production of specific autoantibodies directed to protein antigens are possible. 相似文献
17.
A case of reflex sympathetic dystrophy is presented in a 12-year-old girl with comorbid conversion disorder. Her identical twin also had a conversion disorder. This is the first reported case of coexistence of reflex sympathetic dystrophy and conversion disorder. It is important for clinicians to be aware that these conditions may coexist since the presentation of symptoms differ, even though there are shared features of treatment. 相似文献
18.
Arif JM; Gairola CG; Glauert HP; Kelloff GJ; Lubet RA; Gupta RC 《Carcinogenesis》1998,19(8):1515-1517
The present study investigated the effects of dietary oltipraz on cigarette
smoke-related lipophilic DNA adduct formation. Female Sprague- Dawley rats
were exposed daily to sidestream cigarette smoke in a whole- body exposure
chamber 6 h/day for 4 consecutive weeks. One group of rats was maintained
on control diet while another group received the same diet supplemented
with either a low (167 p.p.m.) or high (500 p.p.m.) dose of oltipraz,
starting 1 week prior to initiation of smoke exposure until the end of the
experiment. Analysis of lipophilic DNA adducts by the nuclease P1-mediated
32P-post-labeling showed up to five smoke-related adducts. Adduct no. 5
predominated in both the lung and the heart while adduct nos 3 and 2
predominated in the trachea and bladder, respectively. Quantitative
analysis revealed that the total adduct level was the highest in lungs
(270+/-68 adducts/10(10) nucleotides), followed by trachea (196+/-48
adducts/10(10) nucleotides), heart (141+/-22 adducts/10(10) nucleotides)
and bladder (85+/-16 adducts/10(10) nucleotides). High dose oltipraz
treatment reduced the adduct levels in lungs and bladder by >60%, while
the reduction in lungs in the low-dose group was approximately 35%. In
trachea, the effect of low and high dietary oltipraz on smoke DNA adduction
was equivocal, while smoke-related DNA adducts in the heart were minimally
inhibited by high-dose oltipraz. In a repeat experiment that employed a
3-fold lower dose of cigarette smoke, oltipraz (500 p.p.m.) was found to
inhibit the formation of DNA adducts in rat lungs and trachea by 80 and
65%, respectively. These data clearly demonstrate a high efficacy of
oltipraz in inhibiting the formation of cigarette smoke-induced DNA adducts
in the target tissues.
相似文献
19.
Suppression of apoptosis in hematopoietic factor-dependent progenitor cell lines by expression of the FAC gene 总被引:2,自引:5,他引:2
Fanconi anemia (FA) is a genetically heterogeneous, inherited blood disorder characterized by bone marrow failure, congenital malformations, and a predisposition to leukemias. Because FA cells are hypersensitive to DNA cross-linking agents and have chromosomal instability, FA has been viewed as a disorder of DNA repair. However, the exact cellular defect in FA cells has not been identified. Sequence analysis of the gene defective in group C patients (FAC) has shown no significant homologies to other known genes. The FAC protein has been localized to the cytoplasm, indicating that FAC may either play an indirect role in DNA repair or is involved in a different cellular pathway. Recent evidence has indicated that FA cells may be predisposed to apoptosis, especially after treatment with DNA cross-linking agents. The demonstration that genes can suppress apoptosis has been accomplished by overexpression of such genes in growth factor-dependent cell lines that die by apoptosis after factor withdrawal. Using retroviral-mediated gene transfer, we present evidence that expression of FAC in the hematopoietic factor-dependent progenitor cell lines 32D and MO7e can suppress apoptosis induced by growth factor withdrawal. Flow cytometry and morphologic analysis of propidium iodide stained cells showed significantly lower levels of apoptosis in FAC-retroviral transduced cells after growth factor deprivation. Expression of FAC in both cell lines promoted increased viability rather than proliferation, which is consistent with other apoptosis-inhibiting genes such as Bcl- 2. These findings imply that FAC may act as a mediator of an apoptotic pathway initiated by growth factor withdrawal. Furthermore, the congenital malformations and hematologic abnormalities characterizing FA may be related to an increased predisposition of FA progenitor cells to undergo apoptosis, particularly in the absence of extracellular signals. 相似文献
20.
Factors that affect human hemopoiesis are produced by T-cell growth factor dependent and independent cultured T-cell leukemia-lymphoma cells 总被引:3,自引:0,他引:3
Some laboratory results and clinical situations suggest that human T cells may be important in the regulation of growth of hematopoietic cells. Since the discovery of T-cell growth factor (TCGF), systems are now available for the long-term specific in vitro propagation of mature normal or neoplastic human T cells, providing an opportunity to study the influence of T cells on hematopoiesis. Recently, 24 cell lines from patients with cutaneous T-cell lymphoma (CTCL) and T-cell acute lymphoblastic leukemia (T-ALL) were grown with TCGF and then assessed for release of humoral factors that affect hematopoiesis. Conditioned media (CM) from these cell lines were tested for erythroid burst- promoting activity (BPA) and granulocyte colony-stimulating activity (CSA). BPA was detected in CM from 3/6 cultures of T-ALL patients and 4/6 CTCL cultures. CSA was found in the CM from 6/8 cultures of T-ALL patients, 7/12 CTCL cultures, and 3/4 CTCL cell lines that become independent of exogenous TCGF for growth. The CSA from several of the neoplastic T-cell cultures stimulated high levels of eosinophil colonies, a possible source of the eosinophilia seen in these patients. The ability of continuously proliferating human T lymphocytes, which retain functional specificity and responsiveness to normal humoral regulation, to produce factors that directly or indirectly stimulate myeloid and erythroid colony formation lends further credence to the role of T lymphocytes in regulating hematopoiesis. 相似文献