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排序方式: 共有441条查询结果,搜索用时 31 毫秒
91.
Duration of breastfeeding was studied in 556 women delivering at 2 maternity hospitals in Perth, Australia. At discharge 83.8% of women were breastfeeding their infants, including 6% who were giving complementary feeds. At 3 and 6 months, 61.8% and 49.9%, respectively, were still breastfeeding. In a Cox survival analysis of factors associated with duration of breastfeeding a positive association was found with maternal education, age and intended duration of breastfeeding. Male infants were more likely to be weaned before female infants and women whose partners were unemployed, or did not have a preference for breastfeeding, breastfed for shorter duration. There is still a need for programmes which support and encourage breastfeeding, focusing particularly on younger, less well-educated women who intend to breastfeed for less than the recommended 4-6 months. 相似文献
92.
Use of a BamHI polymorphism in the factor IX gene for the determination of hemophilia B carrier status 总被引:8,自引:0,他引:8
A BamHI polymorphism has been identified in the human factor IX gene. This polymorphism, which occurs in approximately 6% of X chromosomes, has been used to determine the carrier status of a female in a family with a history of hemophilia B. This family was uninformative for the previously reported TaqI and Xmnl polymorphisms in the factor IX gene. 相似文献
93.
94.
Analysis of a family of cyclin-dependent kinase inhibitors: p15/MTS2/INK4B, p16/MTS1/INK4A, and p18 genes in acute lymphoblastic leukemia of childhood 总被引:11,自引:4,他引:11
Takeuchi S; Bartram CR; Seriu T; Miller CW; Tobler A; Janssen JW; Reiter A; Ludwig WD; Zimmermann M; Schwaller J 《Blood》1995,86(2):755-760
A newly recognized family of proteins that inhibit cyclin-dependent kinases (CDKs) termed cyclin-dependent kinase inhibitors (CDKI) have an important role in regulation of cell-cycle progression. A subfamily of these CDKIs (p15INK4B/MTS2, p16INK4/MTS1, and p18) have a high degree of structural and functional homology and are candidate tumor- suppressor genes. We evaluated the mutational status of the p15, p16, and p18 genes in 103 childhood acute lymphoblastic leukemia (ALL) samples and correlated these results with both their clinical data and additional results concerning their loss of heterozygosity in the region of the p15/p16 genes. Homozygous deletions of the p16 gene occurred extremely frequently in T-ALLs (17/22; 77%), and it was also frequent in precursor-B ALLs (12/81; 15%). Homozygous deletions of the p15 gene were also very frequent in T-ALLs (9/22; 41%), and it occurred in 5 of 81 (6%) precursor-B ALL samples. No deletions of p18 was found in any of the 103 ALL samples. Also, no point mutations of the p15, p16, and p18 genes were detected. We correlated p15/p16 alterations at diagnosis with their clinical characteristics as compared with 2,927 other patients treated similarly. Those with p15/p16 alterations were older; had higher white blood cell counts, often with T-cell ALL phenotype; and more frequently had a mediastinal mass at presentation; but they had the same nonremission, relapse, and survival rates at 5 years as did those patients whose blast cells did not have a p15/p16 deletion. To better understand the extent of alterations affecting chromosome 9p21 (location of the p15/p16 genes), loss of heterozygosity (LOH) was examined at D9S171, which is about 1 megabase proximal to the p15/p16 genes. LOH was detected in 15 of 37 (41%) informative samples. Interestingly, of the 24 informative samples that had no detectable alteration of the p15/p16 genes, 7 samples (29%) had LOH at D9S171. In summary, we show in a very large study that p15 and p16, but not p18, CDKI genes are very frequently altered in ALL; those with p15/p16 alterations are more frequently older children, have higher white blood cells at presentation, and often have a T-cell ALL phenotype. The LOH analysis suggests that another tumor-suppressor gene important in ALL also is present on chromosome 9p21. 相似文献
95.
96.
The list of immunodeficiency diseases grows each year as novel disorders are discovered, classified, and sometimes reclassified due to our ever‐increasing knowledge of immune system function. Although the number of patients with secondary immunodeficiencies (SIDs) greatly exceeds those with primary immunodeficiencies (PIDs), the prevalence of both appears to be on the rise probably because of scientific breakthroughs that facilitate earlier and more accurate diagnosis. Primary immunodeficiencies in adults are not as rare as once thought. Globally, the main causes of secondary immunodeficiency are HIV infection and nutritional insufficiencies. Persons with acquired immune disorders such as AIDS caused by the human immunodeficiency virus (HIV) are now living long and fulfilling lives as a result of highly active antiretroviral therapy (HAART). Irrespective of whether the patient's immune‐deficient state is a consequence of a genetic defect or is secondary in nature, dental and medical practitioners must be aware of the constant potential for infections and/or expressions of autoimmunity in these individuals. The purpose of this review was to study the most common conditions resulting from primary and secondary immunodeficiency states, how they are classified, and the detrimental manifestations of these disorders on the periodontal and oral tissues. 相似文献
97.
98.
Tsirpanlis G Boufidou F Manganas S Chantzis K Bleta A Stamatelou K Psimenou E Nicolaou C 《Blood purification》2004,22(6):518-524
BACKGROUND: Hemodialysis (HD) patients are frequently in an elevated inflammatory state which is correlated to the atherosclerosis-related and overall morbidity and mortality in this population. Statins, beyond their antilipidemic effects, are also considered to have anti-inflammatory, immunomodulating and antioxidant properties. The individual response of HD patients to a short course of fluvastatin, the mechanisms involved in the immunomodulating and anti-inflammatory effects of this drug and the time interval to the appearance of these effects are investigated in this longitudinal study. METHODS: In a group of 51 HD patients, fluvastatin 40 mg/day was administered for 4 weeks. Serial measurements of the lipid profile, C-reactive protein (CRP), interleukin-6 (IL-6), soluble IL-6 receptor (sIL-6R), interleukin-10 (IL-10), and serum oxidized LDL (ox-LDL), were performed before, during, and after the treatment period. RESULTS: Total cholesterol was significantly reduced after 14 days of treatment with fluvastatin (from mean +/- SD 216.7 +/- 34.3 to 179.2 +/- 42.3 mg/dl, p < 0.001). IL-6 and ox-LDL were reduced on day 28 (p < 0.001 and p < 0.01, respectively) and IL-10 was increased on day 14 (p = 0.05); CRP did not change significantly during the treatment period while sIL-6R was increased on day 28 of fluvastatin administration (p < 0.05). In a subgroup of patients with CRP, IL-6, sIL-6R, and ox-LDL baseline serum values > or = the median and IL-10 < or = the median, CRP was reduced on day 28 of fluvastatin treatment (p < 0.01), IL-6 and ox-LDL were reduced earlier, on day 14 (p = 0.05 and p < 0.05, respectively) while sIL-6R did not change significantly during the treatment period. CONCLUSIONS: Treatment with fluvastatin rapidly modulates inflammation in HD patients. Enhancement of anti-inflammatory mechanisms and attenuation of the inflammatory and oxidative state contribute to this modulation. Patients in an elevated baseline inflammatory state respond more rapidly and effectively to the treatment. This immediate and multi-potent action of the statins could be clinically useful in acute atherosclerosis complications or in the treatment of chronic inflammation in HD patients. 相似文献
99.
Abnormal stimulated adherence of neonatal granulocytes: impaired induction of surface Mac-1 by chemotactic factors or secretagogues 总被引:10,自引:0,他引:10
To identify possible secretory determinants of impaired hyperadherence and stimulated migration of neonatal granulocytes (NGs), we performed correlative studies of: (a) specific granule content and exocytosis, (b) secretago-gue-mediated upregulation of f-met-leu-phe (fMLP) receptors, (c) the chemotactic induction of the adhesive glycoproteins Mac-1 alpha (complement receptor 3) and beta, and (d) morphometric assessments of specific (peroxidase negative) granule depletion following chemotactic stimulation. Lactoferrin (LF) content of NG suspensions (cord blood or peripheral blood cells) was profoundly diminished (mean +/- SD 51% +/- 18% of normal) as compared with healthy adult granulocytes (AGs). Despite diminished cellular content, LF release by NG suspensions in response to fMLP was comparable to that of AGs. In contrast, LF release by NG suspensions was significantly diminished in response to phorbol myristate acetate (PMA) or calcium ionophor A23187 and/or during stimulated cell spreading, experimental conditions promoting overall greater LF depletion than chemotactic stimuli. In addition, NGs demonstrated an impaired capacity to upregulate fMLP receptors in response to PMA or A23187 when tested under the same experimental conditions. Baseline expression of the adhesive glycoproteins Mac-1 alpha and beta on NG surfaces was normal, but induction or upregulation of these proteins by chemotactic concentrations of fMLP, C5a as well as secretory (high) concentrations of PMA and A23187, was significantly diminished as compared with AGs. In contrast, chemotactic induction of the surface expression of the complement receptor-1 (CR-1) on NGs was normal. An impaired induction of Mac-1 alpha or beta was directly related to an impaired enhancement of adherence of NG in response to fMLP over a chemotactically relevant concentration range (10(-10) to 10(-7) mol/L). Moreover, in blocking- incubation experiments using anti-Mac-1 alpha/beta monoclonal antibodies (MAbs), significantly less inhibition of adherence by these MAbs was evident with fMLP-stimulated NG as compared with AG suspensions. Under selected chemotactic conditions, ultrastructural assessments of NGs demonstrated diminished peroxidase-negative granule loss in association with diminished granule-membrane fusion and the "addition" of plasma membrane. These studies suggest that abnormal expression of multiple surface determinants derived from peroxidase- negative granules or other intracellular pools may contribute to deficient chemotaxis or other inflammatory functions of NGs.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
100.
Edmond?SK?MaEmail author Chris?LP?Wong Kristi?TW?Lai Edmond?CH?Chan WC?Yam Angus?CW?Chan 《BMC infectious diseases》2005,5(1):60