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91.
B D Mitchell L A Almasy D L Rainwater J L Schneider J Blangero M P Stern J W MacCluer 《American journal of epidemiology》1999,149(11):1047-1056
There is a strong familial predisposition to type 2 diabetes, hypertension, and cardiovascular disease. The authors evaluated the association between a family history of these diseases and a large panel of cardiovascular risk factors in 1,431 Mexican American subjects who were enrolled in the San Antonio Family Heart Study in San Antonio, Texas. The baseline phase of the study covered 1992-1996. Diabetes and hypertension were diagnosed according to standard clinical criteria, while cardiovascular disease was defined as a history of heart attack or heart surgery. The prevalence of diabetes, hypertension, and cardiovascular disease in this population was 15%, 12%, and 3%, respectively. For each unaffected subject, the authors computed a family history score based on the presence or absence of disease in parents and older siblings, and correlations between cardiovascular risk factors and family history scores were estimated by using likelihood-based variance component methods. Diabetes family history score was significantly correlated with a broad panel of cardiovascular risk factors, including glucose and insulin, obesity, blood pressure, triglycerides, and total cholesterol. Hypertension family history score was significantly correlated with glucose, blood pressure, body mass index, waist circumference, total cholesterol, and triglycerides. These results support the idea that genes that confer a risk for diabetes, and to a lesser extent hypertension, adversely alter the cardiovascular risk profile long before the manifestation of clinical disease. 相似文献
92.
93.
In class II major histocompatibility complex (MHC) proteins, residue beta57 is usually aspartic acid. Alleles carrying serine, valine, or alanine at this position are strongly correlated with the development of insulin-dependent diabetes mellitus (IDDM). Asp(beta)57 participates in a conserved salt bridge that bridges the alpha and beta subunits in the peptide-binding site. It has been proposed that the correlation between IDDM and MHC alleles lacking Asp(beta)57 may be due to an instability of the protein caused by loss of this salt bridge. Using a pair of HLA-DQ proteins (alpha1*0201, beta1*0302) and (alpha1*0201, beta1*0303) differing only in having aspartic acid or alanine at position beta57, we show that the polymorphism does not have a significant effect on protein stability for either the empty or peptide-loaded forms. However, the circular dichroism spectra indicate that empty and peptide-loaded Alabeta57 proteins display slightly different secondary structures relative to their Aspbeta57 counterparts. A set of three peptides shows different binding affinities for DQ(alpha1*0201, beta1*0302) relative to DQ(alpha1*0201, beta1*0303). We propose that substitution of Asp(beta)57 residue causes a local rearrangement within the DQ peptide-binding site that alters the peptide-binding specificity. This rearrangement may help to explain the previously observed differences in SDS stability between Asp and non-Asp(beta)57 DQ proteins. 相似文献
94.
Genia Rozen Stephanie Sii Franca Agresta Debra Gook Alex Polyakov Catharyn Stern 《Reproductive Medicine and Biology》2021,20(3):277-288
Purpose
Uncertainties remain regarding the clinical efficacy of ovarian tissue cryopreservation and grafting. We report a retrospective analysis of reproductive outcomes and lessons learnt following 55 ovarian tissue transplant procedures at our center from 2006 to 2019.Methods
We analyzed variables related to graft success such as tissue volume, follicular density, total follicular volume, and age on the duration of graft function.Results
Follicular density and total follicular volume correlate positively with duration of graft function. All clinical pregnancies in our cohort occurred in women who were aged 35 or less at the time of ovarian tissue cryopreservation.Conclusion
Graft success, as determined by eventual pregnancy and the longevity of graft function, may be impacted by factors including age at cryopreservation, follicular density, and total follicular volume.95.
Rey-Osterrieth Complex Figure (ROCF) productions from 18 adults with Attention Deficit Hyperactivity Disorder (ADHD) were compared to 18 matched controls using the Boston Qualitative Scoring System (BQSS). ADHD adults showed impairment in measures of configural accuracy, planning, and neatness. A logistic regression model resulted in 75% sensitivity and 81% specificity in discriminating ADHD from control subjects. In contrast, there was no significant difference on the traditional ROCF 36-point score, and the sensitivity and specificity for the 36-point score were lower (68% and 71%, respectively). These findings suggest persisting executive dysfunction in adults with ADHD that can be detected in ROCF productions. Thus, the BQSS may be a useful tool contributing to the neuropsychological evaluation of adults with ADHD. 相似文献
96.
Slow deep breathing prevents the development of tachygastria and symptoms of motion sickness 总被引:4,自引:0,他引:4
Jokerst MD Gatto M Fazio R Stern RM Koch KL 《Aviation, space, and environmental medicine》1999,70(12):1189-1192
BACKGROUND: The purpose of this study was to see if slow deep breathing, a non-pharmacological procedure known to increase parasympathetic nervous system (PNS) activity, would prevent the development of gastric dysrhythmias and symptoms of motion sickness when subjects were exposed to a rotating optokinetic drum. METHODS: Participating in this study were 46 healthy males and females aged 17-26 who were pre-tested in the rotating drum and found to be susceptible to motion sickness. They were randomly placed into one of the following three conditions: Slow Deep Breathing (n = 18), Counting Breaths (subjects were asked to count their breaths and asked for the count every 3 min, n = 16), and Control (subjects breathed normally, n = 12). Electrogastrograms were recorded from all subjects during a 6-min baseline and a 16-min rotation period. Subjects were asked about their symptoms every 3 min. RESULTS: A significant difference in percent tachygastria from baseline to rotation was found between the three conditions. Percent tachygastria increased during rotation for the Counting Breaths group and the Control group, but remained the same as baseline for the Slow Deep Breathing group. The Slow Deep Breathing group (5.3) reported significantly fewer symptoms than the Counting Breaths group (9.0), but not the Control group (7.8). CONCLUSION: In conclusion, slow deep breathing in a situation previously demonstrated to provoke tachygastria prevented the development of gastric dysrhythmias and decreased symptoms of motion sickness. 相似文献
97.
Alterman RL Reiter GT Shils J Skolnick B Arle JE Lesutis M Simuni T Colcher A Stern M Hurtig H 《Stereotactic and functional neurosurgery》1999,72(2-4):150-153
The authors assess the accuracy of targeting nucleus ventralis intermedius (Vim) with fast spin echo inversion recovery (FSE/IR) magnetic resonance imaging (MRI) in 18 successful deep brain stimulator (DBS) implants for medically refractory tremor. FSE/IR-MRI-derived coordinates are compared to the final coordinates employed for DBS lead placement, selected with intraoperative neurophysiology. The authors conclude that FSE/IR MRI is sufficiently reliable to serve as the sole means of anatomically targeting Vim for DBS lead placement. An independent computer workstation is not required for accurate targeting; however, intraoperative neurophysiology remains essential. 相似文献
98.
Alexopoulos GS Bruce ML Silbersweig D Kalayam B Stern E 《Dialogues in clinical neuroscience》1999,1(2):68-80
We have suggested that cerebrovascular disease may predispose, precipitate, or perpetuate some late-life depressive syndromes. The mechanisms of "vascular depression" include disruption of cortico-striato-pallido-thalamo-cortical (CSPTC) pathways or their modulating systems. This view is supported by the presentation of vascular depression, which consists of depressive symptoms, cognitive abnormalities, as well as neuroimaging findings that may result from CSPTC impairment. Moreover, clinical and electrophysiological evidence of CSPTC impairment, an abnormality frequently found in patients with vascular depression, appears to be associated with poor response to antidepressant treatment and early relapse and recurrence. The vascular depression hypothesis provides the conceptual background for studies that may have clinical and theoretical impact. Agents influencing dopamine, acetylcholine, and opioid neurotransmitters may be studied in vascular depression, since these are essential neurotransmitters of the frontostriatal circuitry. Drugs used for prevention and treatment of cerebrovascular disease may be shown to reduce the risk for vascular depression or improve its outcomes. The choice of antidepressants in vascular depression may depend on their effect on neurological recovery from ischemic lesions. Finally, identification of specific relationships between specific symptoms, cognitive deficits, and disability may lead to interventions that target the patients' deficits as well as their interactions with psychosocial factors known to contribute to depression. Research can clarify the pathways to vascular depression by focusing on the site of lesion, the resultant brain dysfunction, the presentation of depression and time of onset, and the contribution of nonbiological factors. 相似文献
99.
Stern L Dannon PN Hirschmann S Schriber S Amytal D Dolberg OT Grunhaus L 《The journal of ECT》1999,15(4):252-257
Electroconvulsive therapy (ECT) is considered to be one of the most effective treatments for patients with major depression and persistent psychosis. Seizure characteristics probably determine the therapeutic effect of ECT; as a consequence, short seizures are accepted as one of the factors of poor outcome. During most ECT courses seizure threshold increases and seizure duration decreases. Methylxanthine preparations, caffeine, and theophylline have been used to prolong seizure duration. The use of aminophylline, more readily available than caffeine, has not been well documented. The objective of this study was to test the effects of aminophylline on seizure length. Fourteen drug-free patients with diagnoses of affective disorder or psychotic episode receiving ECT participated in this study. Seizure length was assessed clinically and per EEG. Statistical comparisons were done using paired t tests. A significant increase (p < 0.04) in seizure length was achieved and maintained on three subsequent treatments with aminophylline. No adverse events were noted from the addition of aminophylline. 相似文献
100.
Optimal histopathologic examination of the sentinel lymph node for breast carcinoma staging 总被引:30,自引:0,他引:30
Turner RR Ollila DW Stern S Giuliano AE 《The American journal of surgical pathology》1999,23(3):263-267
Sentinel lymph node dissection is a minimally invasive surgical technique for staging of breast carcinoma. The optimal pathologic examination of the sentinel node (SN) has not yet been determined. Our standard protocol for evaluation of the SN in patients with breast cancer included frozen section at one level, plus paraffin sections at two levels, separated by 40 microm, and stained with hematoxylin and eosin and cytokeratin immunohistochemistry (IHC) at each paraffin section level. In the current study, we evaluated the use of step sections and cytokeratin IHC in 60 SNs (42 consecutive patients) that were tumor-negative on frozen section and hematoxylin and eosin staining at permanent section levels 1 and 2. The SN were reexamined with cytokeratin IHC at eight additional levels (levels 3-10) of the paraffin block, each separated by 40 microm. Previous IHC sections from levels 1 and 2 had shown micrometastases in nine SNs (eight patients) and no tumor cells in the remaining 51 SNs (34 patients). Of the 51 previously negative SNs, only two (4%) SNs from one (3%) patient had metastatic carcinoma cells in levels 3-10. Thus, the additional step sections with cytokeratin IHC did not significantly increase the number of patients with tumor-positive SNs. We currently recommend that the SN be examined with cytokeratin IHC at two levels of the paraffin block. This should optimize sentinel lymph node dissection as a staging technique and minimize the labor and financial burden associated with multiple step sections and IHC stains. 相似文献