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81.
82.
An apparently balanced reciprocal translocation 46,X,t(Y;6) (q11.23 ∼ q12;p11.1) was observed in an infertile man with severe oligozooteratozoospermia. Different mitotic chromosome banding patterns were performed and fluorescence in situ hybridization indicated a breakpoint in the fluorescent Yq heterochromatin. Molecular genetic deletion experiments for the azoospermia factor region in distal Yq11 showed the retention of the DAZ gene and meiotic pairing configurations suggested that the man’s infertility could be due to the pairing behaviour of the Y;6 translocation chromosome with the X chromosome visualised by synaptonemal complex analysis at the electron microscopy level. The morphological appearance of the normal chromosome 6 and the Y;6 translocated chromosome included in the compartment of the sex vesicle may allow an explanation of the degeneration of most spermatocytes after the pachytene stage. Received: 1 August 1997 / Accepted: 25 September 1997  相似文献   
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84.
Ochratoxin A: Occurrence as Natural Contaminant of a Corn Sample   总被引:8,自引:7,他引:1       下载免费PDF全文
Ochratoxin A was detected as a natural contaminant for the first time. It was present in a corn sample.  相似文献   
85.
This study builds on the findings that physical activity, such as wheel running in mice, enhances cell proliferation and neurogenesis in the adult hippocampus of the common mouse strain C57BL/6, and that the baseline level of neurogenesis varies by strain, being considerably lower in DBA/2. Because C57BL/6 and DBA/2 are important as the parental strains of the BXD recombinant inbred cross which allows the detection of genetic loci regulating phenotypes such as adult neurogenesis, we performed the current study to investigate the gene x environment interactions regulating neurogenesis. At equal distances and times run DBA/2J mice lacked the acute increase in precursor cell proliferation known from C57BL/6. In DBA/2J proliferation even negatively correlated with the distance run. This was neither due to a stress response (to running itself or single housing) nor differences in estrous cycle. DBA/2 animals exhibited a delayed and weaker pro-neurogenic response with a significant increase in numbers of proliferating cells first detectable after more than a week of wheel running. The proliferative response to running was transient in both strains, the effect being undetectable by 6 weeks. There was also a small transient increase in the production of new neurons in DBA/2J, although these extra cells did not survive. These findings indicate that the comparison between C57BL/6 and DBA/2, and by extension the BXD genetic reference population derived from these strains, should provide a powerful tool for uncovering the complex network of modifier genes affecting the activity-dependent regulation of adult hippocampal neurogenesis. More generally, our findings also describe how the external physical environment interacts with the internal genetic environment to produce different responses to the same behavioral stimuli.  相似文献   
86.
EBV, a B lymphotropic herpesvirus, encodes two immediate early (IE)-, >30 early (E)-, and >30 late (L)-phase proteins during its replication (lytic) cycle. Despite this, lytic Ag-induced CD8 responses are strongly skewed toward IE and a few E proteins only, all expressed before HLA I presentation is blocked in lytically infected cells. For comparison, we examined CD4(+) T cell responses to eight IE, E, or L proteins, screening 14 virus-immune donors to overlapping peptide pools in IFN-γ ELISPOT assays, and established CD4(+) T cell clones against 12 defined epitopes for target-recognition assays. We found that the lytic Ag-specific CD4(+) T cell response differs radically from its CD8 counterpart in that it is widely distributed across IE, E, and L Ag targets, often with multiple reactivities detectable per donor and with IE, E, or L epitope responses being numerically dominant, and that all CD4(+) T cell clones, whether IE, E, or L epitope-specific, show strong recognition of EBV-transformed B cell lines, despite the lines containing only a small fraction of lytically infected cells. Efficient recognition occurs because lytic Ags are released into the culture and are acquired and processed by neighboring latently infected cells. These findings suggested that lytic Ag-specific CD4 responses are driven by a different route of Ag display than drives CD8 responses and that such CD4 effectors could be therapeutically useful against EBV-driven lymphoproliferative disease lesions, which contain similarly small fractions of EBV-transformed cells entering the lytic cycle.  相似文献   
87.
Plant species richness (PSR) increases nutrient uptake which depletes bioavailable nutrient pools in soil. No such relationship between plant uptake and availability in soil was found for phosphorus (P). We explored PSR effects on P mobilisation [phosphatase activity (PA)] in soil. PA increased with PSR. The positive PSR effect was not solely due to an increase in Corg concentrations because PSR remained significant if related to PA:Corg. An increase in PA per unit Corg increases the probability of the temporal and spatial match between substrate, enzyme and microorganism potentially serving as an adaption to competition. Carbon use efficiency of microorganisms (Cmic:Corg) increased with increasing PSR while enzyme exudation efficiency (PA:Cmic) remained constant. These findings suggest the need for efficient C rather than P cycling underlying the relationship between PSR and PA. Our results indicate that the coupling between C and P cycling in soil becomes tighter with increasing PSR.  相似文献   
88.

Introduction

The sacroiliac joint (SIJ) is a common source of low back pain. However, clinical and functional signs and symptoms correlating with SIJ pain are widely unknown. Pelvic belts are routinely applied to treat SIJ pain but without sound evidence of their pain-relieving effects. This case-control study compares clinical and functional data of SIJ patients and healthy control subjects and evaluates belt effects on SIJ pain.

Methods

17 SIJ patients and 17 healthy controls were included in this prospective study. The short-form 36 survey and the numerical rating scale were used to characterize health-related quality of life in patients in a six-week follow-up and the pain-reducing effects of pelvic belts. Electromyography data were obtained from the gluteus maximus, biceps femoris, rectus femoris and medial vastus. Alterations of muscle activity, variability and gait patterns were compared in patients and controls along with the belts’ effects in a dynamic setting when walking.

Results

Significant improvements were observed in the short-form 36 survey of the SIJ patients, especially in the physical health subscores. Minor declines were also observed in the numerical rating scale on pain. Belt-related changes of muscle activity and variability were similar in patients and controls with one exception: the rectus femoris activity decreased significantly in patients with belt application when walking. Further belt effects include improved cadence and gait velocity in patients and controls.

Conclusions

Pelvic belts improve health-related quality of life and are potentially attributed to decreased SIJ-related pain. Belt effects include decreased rectus femoris activity in patients and improved postural steadiness during locomotion. Pelvic belts may therefore be considered as a cost-effective and low-risk treatment of SIJ pain.

Trial Registration

ClinicalTrials.gov NCT02027038  相似文献   
89.
The lipase A, lysosomal acid, cholesterol esterase enzyme (LIPA) is involved in the hydrolysis of triglycerides (TGs) and cholesteryl esters (CEs) delivered to lysosomes. LIPA deficiency in human causes two distinct phenotypes characterized by intracellular storage of CE and derangements in the control of cholesterol production, namely the Wolman disease (WD) and the CE storage disease (CESD). To test the potential association of LIPA gene polymorphisms with obesity-related metabolic complications, promoter, exons, and intronic flanking regions of the LIPA gene were first sequenced in 25 individuals. From the 14 common polymorphisms identified, 12 tagging single-nucleotide polymorphisms (tSNPs) were genotyped in a cohort of 1,751 obese individuals. After adjustments for the effect of age, sex, diabetes, and medication, the C allele of SNP rs1051338 was associated with lower blood pressure (BP; systolic (SBP) P = 0.004; diastolic (DBP) P = 0.006). Three of the tested SNPs were associated with modifications of the plasma lipid profile. The G/G genotype of rs2071509 was associated with higher high-density lipoprotein cholesterol (HDL-C) levels (P = 0.009) and minor allele of rs1131706 was also associated with higher HDL-C (P = 0.004) and an association between rs3802656 and total cholesterol (total-C)/HDL-C ratio was identified (P = 0.04). These results thus suggest that LIPA polymorphisms contribute to the interindividual variability observed in obesity-related metabolic complications.  相似文献   
90.
Background: Although cardiovascular disease (CVD) is the leading cause of death in women in the United States, a knowledge gap persists regarding the mechanisms and management of CVD in women. Before treatment can be optimized, the role of cardiovascular risk factors must be elucidated.Objective: This review provides an updated assessment of cardiovascular risk factors in women, with a focus on cardiometabolic risk.Methods: MEDLINE and Cochrane Library databases, and statistics from the National Health and Nutrition Examination Survey and the American Heart Association, were searched from 1990 to September 2008 using the following terms: cardiovascular risk factors, women, gender, cardiometabolic risk, abdominal obesity, and metabolic syndrome. Publications were classified as English-only original data, reviews, and clinical guidelines. Nonpublished data were excluded. Data were extracted by 2 reviewers independently.Results: Investigators performing multivariable predictive models have estimated that traditional risk factors account for ~70% of the variance in estimating cardiovascular events. However, substantial sex differences exist in the prevalence of traditional risk factors as well as in cardiovascular outcomes. Hypertension is more prevalent in men until the age of 59 years, but then contributes to greater morbidity in older women. Low levels of high-density lipoprotein and elevated triglyceride levels pose more of a threat to women, yet high levels of low-density lipoprotein pose equal risk for women and men. The CVD mortality rate is -3 times greater in people with diabetes than in those without diabetes. Among diabetic individuals, CVD mortality is slightly higher in women compared with men.Conclusions: Increased knowledge of gender-specific risks for CVD has led to national campaigns to educate women. In addition to traditional risk factors, cardiometabolic risk is an important consideration in women. Controversy exists regarding the exact definitions and usefulness of the term metabolic syndrome, but it is clear that the presence of certain factors contributes to increased morbidity and mortality in affected individuals. Abdominal obesity links insulin resistance, dyslipidemia, and hypertension through complex endocrine pathways. Current research is identifying gene × gender interactions, and continued research is necessary to explore the relationship of sex steroids and cardiovascular risk in both men and women.  相似文献   
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