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1.
The location of the HYP gene, which determines X-linked hypophosphataemic rickets, has been refined considerably by linkage analysis, and three new microsatellite primers isolated, Cap32 (DXS7473), Cap29 (DXS7474) and 7v2 (DXS7475). The locations of four other markers have also been determined (DXS1226, AFMa176zb1, AFMa152wc5, and AFM346azc1). Markers Cap29 and Cap32 are the closest distal markers to the gene with zetamax=11.93, thetamax= 0.018 and zetamax=12.03, thetamax = 0.015 respectively. Both Cap29 and Cap32 are proximal to DXS365 and AFMa176zb1, as deduced by screening non-chimaeric yeast artificial chromosomes (YACs) from a contig spanning the HYP gene. A single crossover places AFMa176zbl distal to the disease gene. There are no recombinations between 7v2 and HYP (zetamax=12.9, thetamax=0.0), or between 7v2 and adjacent markers Cap32, Cap29, AFMa176zb1, DXS1683 and DXS365. However screening of YAC clones encompassing the HYP gene and also P1 clones localises 7v2 distal to Cap29 and Cap32, and proximal to DXS443. Marker DXS1226 is placed outside the region containing the gene, and is located proximal to DXS274 as confirmed by a crossover for this marker and DXS41 against HYP and its presence on YAC 83B05. Genetic mapping of CEPH pedigrees, and screening of YACs places AFMa152wc5 and AFMa346zcl between DXS1683 and DXS1052. The following gene marker map presents the best order for the HYP region: Xptel-DXS43-DXS999-DXS443-(DXS365/DXS74 75/AFMa176zb1)-(DXS7474/DXS7473)-HYP- DXS1683-(AFMa152wc5/AFMa346zc1)-DXS1052-DXS 274 -(DXS41/DXS1226)-Xcen. The distance between the cluster of distal flanking markers Cap29 (DXS7474), Cap32 (DXS7473), and DXS1683 is approximately 300 kb, as deduced from physical map data from a YAC contig spanning the gene. Thus the gene for HYP is contained within a single YAC (900AO472). Of further interest, is the location of a putative vitamin D response element (VDRE) on this YAC.  相似文献   

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OBJECTIVE: Syndrome X (angina, normal coronary arteriogram and positive exercise test) remains an enigma with unexplained features and apparent conflicts of evidence. The present study addressed whether (i) the Syndrome is characterised by generalised flow-related endothelial dysfunction, (ii) myocardial thallium201 defects reflect myocardial or microvascular dysfunction, (iii) endothelial dysfunction and its consequences can be improved by oral L-arginine. METHODS: Flow-mediated brachial artery dilatation was measured by ultrasonic 'wall-tracking' in 7 Syndrome X patients, further characterised as having thallium201 defects and no known cause of endothelial dysfunction, and a normal control group. Syndrome X patients entered a 4-week randomised double-blind placebo-controlled cross-over trial of oral L-arginine (7 g twice daily), with brachial artery studies, exercise tests and technetium99 tetrafosmin scans. RESULTS: Flow-mediated dilatation was absent in Syndrome X vs. normal. Stress technetium99 tetrafosmin and thallium201 scans showed similar defects. Flow-mediated dilatation, symptom-limited exercise duration and peak oxygen consumption (VO2max) were increased but rate-pressure-product (RPP) and radionuclide defects were unchanged after L-arginine vs. placebo. CONCLUSIONS: The study supports coronary microvascular rather than myocardial dysfunction and shows loss of flow-mediated dilatation in systemic arteries. Oral L-arginine improved flow-mediated dilatation, exercise capacity and VO2max (by ca. 17%) despite unchanged RPP. The findings support generalised endothelial dysfunction. The arginine effects imply NO-mediated improvement of skeletal muscle perfusion suggesting improved homogeneity of microvascular distribution.  相似文献   

4.
Viral respiratory infections cause acute airway abnormalities consisting of inflammation and physiological dysfunction in both animals and humans. It is likely that inflammatory cell products, such as cytokines, contribute substantially to viral-induced airway dysfunction. We hypothesized that imiquimod, an immune response enhancing agent that induces interferon-alpha, would attenuate the development of airway dysfunction during acute viral illness in rats. Adult Brown Norway rats were inoculated with parainfluenza type 1 (Sendai) virus or sterile vehicle, and treated with either imiquimod or water. Respiratory system resistance (Rrs), arterial oxygen tension (Pa,O2), lung viral titres and bronchoalveolar lavage (BAL) leucocyte counts were measured in anaesthetized, paralysed, ventilated rats. Virus-infected, water-treated rats had a significant decrease in Pa,O2 and had significant increases in leucocyte count and Rrs when compared to both the virus-infected, imiquimod-treated, (Pa,O2, p = 0.03; leucocyte count, p = 0.02; and Rrs, p = 0.009) and noninfected, water-treated rats (Pa,O2, p = 0.007; leucocyte count, p = 0.001; and Rrs, p = 0.01). In addition, imiquimod suppressed BAL eosinophils in both virus-infected (p = 0.02) and noninfected (p = 0.001) groups, and lowered overall virus titres (p = 0.03). Thus, both virus-induced airway inflammation and physiological dysfunction were attenuated significantly by imiquimod treatment in this animal model. By further delineating mechanisms by which infections induce airway dysfunction in animal models, more specific pharmacological interventions can be developed for the treatment of virus-induced asthma.  相似文献   

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Archival paraffin-embedded tissue from 5 normal adrenal glands (including 1 from a fetus of 28 weeks' gestation), 6 cases of adrenal cortical hyperplasia, 9 cortical adenomas, 14 cortical carcinomas, and 11 pheochromocytomas were immunostained with monoclonal antibody against bcl-2. Ultrastructural localization of bcl-2 protein was also performed on selected cases. Positive immunostaining for bcl-2 was seen in all of the layers of the normal adrenal cortex, with different staining characteristics. bcl-2 expression was never observed in the normal adrenal medulla. Electron microscopic studies revealed bcl-2 to be localized predominantly to mitochondria, with a small number of labels along the nuclear envelope. Analysis of adrenal neoplasms showed expression of bcl-2 in cortical tumors, but only one positive case in pheochromocytomas. Restriction of bcl-2 expression to adrenal cortex-derived tissue versus adrenal medulla-derived tissue might prove to be helpful for the differential diagnosis between cortical and medullary tumors.  相似文献   

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Several studies have shown impairment of endothelium-dependent relaxations as well as increased release of vasoconstrictor prostanoids in arteries from diabetic animals and humans. This impairment is restored towards normal by prostaglandin (PG) H2/thromboxane A2 receptor blockade or superoxide dismutase, indicating that the PGH2 and/or superoxide anion (O2-.) generated contributes to the abnormality. Of particular note is that PGH2 impairs endothelium-dependent relaxations and causes contractions by a mechanism that involves generation of O2-. in the endothelium. The effects of elevated glucose are exacerbated by increased aldose reductase activity leading to depletion of NADPH and generation of reactive oxidants. Because NADPH is required for generation of nitric oxide from L-arginine, the depletion of NADPH leads to reduced nitric oxide formation. In a manner similar to that observed with elevated glucose, oxygen-derived free radicals or activation of protein kinase C also cause impairment of endothelium-dependent relaxations, smooth muscle contractions, and release constrictor prostanoids, indicating that a common mechanism for the impairment of endothelial cell function may be operative in diabetes. In this review the cumulative effects of oxidative stress on diabetic endothelial cell dysfunction, together with the complex interrelationship of cyclooxygenase catalysis, protein kinase C activity, and flux through the polyol pathway, are considered.  相似文献   

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Bacterial lipopolysaccharide induces tyrosine phosphorylation of paxillin, actin reorganization, and opening of the transendothelial paracellular pathway through which macromoles flux. In this study, lipid A was shown to be the bioactive portion of the lipopolysaccharide molecule responsible for changes in endothelial barrier function. We then studied whether endotoxin-neutralizing protein, a recombinant peptide that is derived from Limulus antilipopolysaccharide factor and targets lipid A, could block the effects of lipopolysaccharide on protein tyrosine phosphorylation, actin organization, and movement of 14C-bovine serum albumin across bovine pulmonary artery endothelial cell monolayers. In the presence of serum, a 6-h exposure to lipopolysaccharide (10 ng/ml) increased transendothelial 14C-albumin flux compared to the simultaneous media control. Coadministration of endotoxin-neutralizing protein (> or =10 ng/ml) with lipopolysaccharide (10 ng/ml) protected against lipopolysaccharide-induced barrier dysfunction. This protection was dose dependent, conferring total protection at endotoxin-neutralizing protein/lipopolysaccharide ratios of > or =10:1. Similarly, endotoxin-neutralizing protein was capable of blocking the lipopolysaccharide-induced endothelial cell responses that are prerequisite to barrier dysfunction, including tyrosine phosphorylation of paxillin and actin depolymerization. Finally, endotoxin-neutralizing protein cross-protected against lipopolysaccharide derived from diverse gram-negative bacteria. Thus, endotoxin-neutralizing protein offers a novel therapeutic intervention for the vascular endothelial dysfunction of gram-negative sepsis and its attendant endotoxemia.  相似文献   

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A captive colony of baboons has been used for three decades for various reproductive studies where application of findings to human therapeutics was desired. The characteristics of the menstrual cycle in baboons are very similar to those of women, except that of the baboon is slightly longer and there is a lower luteal phase concentration of oestradiol. The duration of pregnancy in baboons is about two-thirds that of humans but patterns of oestrogen and progesterone secretion are virtually identical. The principal oestrogen produced by the pregnant baboon is oestrone, while oestriol is the most abundant in human pregnancies. Chorionic gonadotrophin (CG) is elevated significantly only in the first trimester of a baboon pregnancy, while human pregnancy concentrations of this hormone are about one-third of the first trimester level in the second and third trimesters. Breeding success of baboons in captivity depends on care being taken to cull infertile animals from the colony prior to commencing matings. Under optimal conditions, fertility rates can reach nearly 80%. Female baboons have been successfully used to gain insights into antifertility effects of contraceptive vaccines directed against CG, spermatozoa and ovum antigens. Extensive use of the colony for developing a human chorionic gonadotrophin (HCG) antifertility vaccine has been invaluable for progress in this field. Other pharmaceuticals and devices have been successfully tested in baboons, but costs and mandated regulations for the management of these nonhuman primates have made their current use in meaningful studies extremely difficult.  相似文献   

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This article describes the structure and development of a successful, rural nurse-midwifery service consisting of nine certified nurse-midwives and four obstetricians. The model has shown that the addition of a nurse-midwifery service and the adoption of a collaborative care model can improve obstetric outcomes. The outcomes of this model include an increase in the number of women served each year, a decrease in the cesarean section rate, an increase in the number of twin gestations delivered vaginally, an increase in the number of breech presentations delivered vaginally, an increase in the success rate of vaginal birth after cesarean section, and decreased numbers of episiotomies, with a resulting decrease in the number of third- and fourth-degree lacerations.  相似文献   

10.
PURPOSE: Multiple primary cancers are a feature of hereditary nonpolyposis colorectal cancer in which defects in DNA repair mechanisms result in accumulation of replication errors within tumor DNA. We assessed replication error incidence in multiple primary cancer patients who may have similar genetic defects. METHODS: DNA was obtained from 69 patients from the Yorkshire region who had developed colorectal cancer and one other primary tumor from the hereditary nonpolyposis colorectal cancer tumor spectrum (28 colorectal, 12 stomach, 15 ovary, and 14 uterus). DNA was also obtained from 86 sporadic, single primary cancer patients attending a colorectal cancer clinic. Replication error status was assessed at five microsatellite loci using fluorescent polymerase chain reaction and computer-assisted analysis. RESULTS: The replication error phenotype was observed in 7 of 86 (8 percent) of the sporadic single primary patients. This compared with 23 of 69 (33 percent) of the multiple primary group (P < 0.001). Replication error was also observed more frequently in each subgroup. Even excluding patients from families meeting the Amsterdam criteria (likely to be hereditary nonpolyposis colorectal cancer and have the replication error phenotype), this increased frequency remained in both the multiple primary group (P < 0.005) and multiple colorectal and colorectal/uterine subgroups (P < 0.001). CONCLUSIONS: Results suggest that genetic instability plays an important role in development of multiple primary cancers, particularly from certain cancer subsets. Testing for replication errors may be an appropriate way of identifying individuals at risk of multiple primary cancers.  相似文献   

11.
We examined the effects of diabetes on eicosanoid metabolism and endothelium-dependent relaxation in isolated aorta from alloxan-induced diabetic rabbits and that from normal rabbits incubated in increased concentrations (44 mM) of glucose in vitro for 6 h. Immunoreactive 15-hydroxyeicosatetraenoic acid (HETE) was assayed in the incubation media of isolated aortic segments. Basal and acetylcholine (ACh)-stimulated release of 15-HETE was significantly greater in aorta of diabetic animals as compared with those of normal rabbits. Incubation of aortic segments from normal rabbits in increased concentrations of glucose caused a significant increase in basal and ACh-stimulated release of 15-HETE; and the release was significantly greater in aortic segments with endothelium than in segments without endothelium. Basal and ACh-stimulated release of 15-HETE was inhibited by indomethacin, a cyclooxygenase inhibitor. 15-HETE caused contractions of aortic rings that were inhibited by the prostaglandin H2 (PGH2) thromboxane A2 (TXA2) receptor blocker SQ-29548, but not by the TXA2 synthase inhibitor carbethoxyhexyl imidazole or indomethacin. Treatment of aortic rings with subthreshold concentrations of 15-HETE impaired ACh-induced relaxation; this was prevented by treatment with SQ-29548. Thus, abnormal release of endothelium-derived 15-HETE may play a role in endothelial cell dysfunction and increased vasoconstriction in diabetes by a mechanism that involves interaction with PGH2/TXA2 receptors.  相似文献   

12.
OBJECTIVE: While elevated blood levels of homocyst(e)ine represent an independent risk factor for macrovascular disease, we assessed the link between hyperhomocyst(e)inemia and diabetic microvascular diseases. RESEARCH DESIGN AND METHODS: Plasma levels of homocyst(e)ine and thrombomodulin (TM), markers of endothelial cell damage, were measured before and 3 h after oral methionine loading in 75 patients with IDDM and 40 healthy control subjects matched for sex and age. Exclusion criteria were hyperlipidemia, hypertension, smoking, or positive family history for cardiovascular disease. RESULTS: IDDM patients had higher pre- and postload plasma levels of homocyst(e)ine than did healthy control subjects (12.0 vs. 7.7 mumol/l and 27.6 vs. 16.0 mumol/l; P < 0.001). Of 75 IDDM patients, 26 had plasma homocyst(e)ine levels above the normal range (means +/- 2 SD of values obtained in the control group). These IDDM patients with hyperhomocyst(e)inemia had higher plasma TM levels (62.2 vs. 38.2 ng/ml, P < 0.001), higher albumin excretion rates (485 vs. 115 mg/l, P < 0.005), and a higher prevalence of late diabetic complications (nephropathy, 76 vs. 33%; retinopathy, 69 vs. 51%; neuropathy, 57 vs. 41%; and macroangiopathy, 57 vs. 33%) compared with IDDM patients with normal plasma homocyst(e)ine. In vitro experiments with human umbilical vein cells showed an increased release of TM into the culture supernatant only when endothelial cells were pretreated with advanced glycation end product (AGE)-albumin before L-homocystine was added. A synergistic action of homocyst(e)ine and AGEs might contribute to vascular complications in patients with diabetes. CONCLUSIONS: Hyperhomocyst(e)inemia is common in nephropathic diabetic patients and may contribute to the enhanced morbidity and mortality from cardiovascular diseases characteristically observed in IDDM patients with diabetic nephropathy.  相似文献   

13.
We have examined whether the development of embryonic muscle fiber type is regulated by competing influences between Hedgehog and TGF-beta signals, as previously shown for development of neuronal cell identity in the neural tube. We found that ectopic expression of Hedgehogs or inhibition of protein kinase A in zebrafish embryos induces slow muscle precursors throughout the somite but muscle pioneer cells only in the middle of the somite. Ectopic expression in the notochord of Dorsalin-1, a member of the TGF-beta superfamily, inhibits the formation of muscle pioneer cells, demonstrating that TGF-beta signals can antagonize the induction of muscle pioneer cells by Hedgehog. We propose that a Hedgehog signal first induces the formation of slow muscle precursor cells, and subsequent Hedgehog and TGF-beta signals exert competing positive and negative influences on the development of muscle pioneer cells.  相似文献   

14.
Loss of functional integrity of the vascular endothelium may be one of the initiating events in the etiology of atherosclerosis. Endothelial cells interact with blood components and the abluminal tissues, thus playing an active role in many aspects of vascular functions, such as permeability and vessel tone regulation. Endothelial cells constantly are exposed to nutrients which can modulate enzymes, receptors, transport molecules and various vasoactive mediators, resulting in significant functional changes of the endothelium and the underlying tissues. Nutrition may play an important role in the atherosclerotic disease process. There is evidence that certain vitamins and minerals prevent some metabolic and physiological perturbations of the vascular endothelium. This review focuses on selected lipids which cause endothelial cell injury or dysfunction and on nutrients which may exhibit antiatherogenic properties by being able to function as antioxidants or membrane stabilizers.  相似文献   

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Explores the nature and development of introspective activity during adolescence. Topics addressed include the relationships among introspection, cognition, and ego identity development; defensive vs adaptive forms of introspection; the function of introspection in borderline and narcissistic adolescents; and the use of a patient"s introspective capacities as a therapeutic tool. The therapist"s need to be sensitive to the tension in adolescents between the benefits of introspection and the anxiety it may engender is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
This study, addressing etiologic and pathogenic aspects of fibromyalgia (FM), aimed at examining whether sensory abnormalities in FM patients are generalized or confined to areas with spontaneous pain. Ten female FM patients and 10 healthy, age-matched females participated. The patients were asked to rate the intensity of ongoing pain using a visual analogue scale (VAS) at the site of maximal pain, the homologous contralateral site and two homologous sites with no or minimal pain. Quantitative sensory testing was performed for assessment of perception thresholds in these four sites. Von Frey filaments were used to test low-threshold mechanoreceptive function. Pressure pain sensitivity was assessed with a pressure algometer and thermal sensitivity with a Thermotest. In addition the stimulus-response curve of pain intensity as a function of graded nociceptive heat stimulation was studied at the site of maximal pain and at the homologous contralateral site. FM patients had increased sensitivity to non-painful warmth (P < 0.01) over painful sites and a tendency to increased sensitivity to non-painful cold (P < 0.06) at all sites compared to controls, but there was no difference between groups regarding tactile perception thresholds. Compared to controls, patients demonstrated increased sensitivity to pressure pain (P < 0.001), cold pain (P < 0.001) and heat pain (P < 0.02) over all tested sites. The stimulus-response curve was parallely shifted to the left of the curve obtained from controls (P < 0.003). Intragroup comparisons showed that patients had increased sensitivity to pressure pain (P < 0.01) and light touch (P < 0.05) in the site of maximal pain compared to the homologous contralateral site. These findings could be explained in terms of sensitization of primary afferent pathways or as a dysfunction of endogenous systems modulating afferent activity. However, the generalized increase in sensitivity found in FM patients was unrelated to spontaneous pain and thus most likely due to a central nervous system (CNS) dysfunction. The additional hyperphenomena related to spontaneous pain are probably dependent on disinhibition/facilitation of nociceptive afferent input from normal (or ischemic) muscles.  相似文献   

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3 different types of complex spinal trauma are defined: Type I means a multilevel contiguous or non contiguous unstable injury, type II is described as a spinal injury with concomitant thoracic or abdominal lesion, type III stands for the coincidence of spinal injury and polytrauma. Overlapping of different types occurs. Type I: The incidence amounts according a german multicenter study to about 2.5%. Multilevel injuries need to be stabilized for a long distance from posterior. With a thorough analysis the segments to be fused are determined. Type II: The leading thoracic injury is a lung contusion which occurs in up to 50% of the cases. A CT scan of the thorax during the first diagnostic screening is recommended. Early reduction and stabilization from posterior should be aimed at. During the first two weeks anterior procedures are contraindicated. Abdominal injuries are to be found in 3-4% of all spinal injuries. All organs could be affected. A typical constallation is the "seat-belt syndrome" with lesions of the upper abdominal organs and a flexiondistraction injury of the upper lumbar spine. The main problem is to make the diagnosis of both components initially. Most of the patients may be treated in one operation by first taking care of the abdominal injury and than stabilizing the spine. The prognosis of this combination is favorable. Type III: In 17-18% of all polytraumatized patients lesions of the spine are to be diagnosed. From these only one third need surgical care. From 680 patients with operatively treated fractures of the thoracolumbar junction 6.2% were polytraumatized according to the multicenter study mentioned above. The risk of missing a spinal injury in polytrauma totals approximately 20%. Surgical stabilization should be performed in the primary phase (day-1-surgery). Additional injuries, potentially time consuming operations with a high blood loss sometimes necessitate a different approach. Non stabilized spinal injuries apparently do not have the same negative effect on the whole organism as long bone fractures. In the early phase of treatment on the C-spine only anterior procedures and on the thoracolumbar spine only posterior techniques should be applied.  相似文献   

19.
BACKGROUND: The mechanisms by which increased pulmonary blood flow results in pulmonary hypertension have not been determined. METHODS: To determine if increased pulmonary blood flow produces endothelial dysfunction that precedes vascular remodeling and smooth muscle proliferation, neonatal swine (n = 12) (age, 6.1+/-0.5 days) underwent ligation of the left pulmonary artery (LPA) to increase blood flow to the right lung. At 12 weeks of age, endothelium-dependent vasodilatation was assessed by acetylcholine infusion and endothelium-independent vasodilatation by inhaled nitric oxide (NO) in the LPA group and age-matched controls (CON) (n = 11). RESULTS: Mean pulmonary artery pressure was 24.1+/-3.0 mm Hg in the LPA group and 20.8+/-1.9 mm Hg in the CON group (p < 0.1). Pulmonary vascular resistance was 13.2+/-2.2 Wood units in the LPA group and 5.8+/-0.8 Wood units in the CON group (p = 0.001). Acute occlusion of the left pulmonary artery in the CON group increased pulmonary vascular resistance to 6.9+/-3.9 Wood units (p = 0.04). Administration of acetylcholine in the CON group after preconstriction with the thromboxane A2 analogue U46619 resulted in a 30.6%+/-5.4% decrease in pulmonary vascular resistance. In the LPA group, acetylcholine produced paradoxical vasoconstriction and a 15.4%+/-4.1% increase in pulmonary vascular resistance (p < 0.001 versus CON) indicating loss of endothelium-dependent vasodilatation. Nitric oxide decreased pulmonary vascular resistance by 41.9%+/-3.3% in the CON group and 30.8%+/-2.7% in the LPA group (p = 0.04 versus CON), indicating preserved endothelium-independent vasodilatation in both groups. Morphometric analysis was performed in 4 animals from each group. Medial wall thickness as percent of external diameter of small arteries (<100 microm) was the same in both groups (6.4%+/-0.4% in the LPA group versus 6.6% +/-0.4% in the CON animals; p > 0.1). CONCLUSIONS: Increased pulmonary blood flow in immature animals produces endothelial cell dysfunction with loss of endothelium-dependent vasodilatation before the onset of pulmonary vascular remodeling. Subsequent smooth muscle proliferation may be mediated by endothelium-derived factors.  相似文献   

20.
Relationships between neurophysiological and immune parameters were studied in normal middle-aged and elderly subjects and in patients with dementia of Alzheimer's type (DAT). The rate of such interaction was minimal in normal aging, in DAT neuroimmune relations increased. The correlation between the immune parameters and the characteristics of components of visual evoked potentials and auditory brain-stem responses suggests that in the middle-aged healthy subjects, a primary role in neuroimmune relations belongs to limbicoreticular structures and to the mesencephalon. In normal aging, the influence of limbicoreticular structures on immune structures decreases. In DAT, the modulation of immune processes by limbicoreticular and thalamocortical structures, as well as the pontobulbar part of the brain stem increases. In middle age and in DAT, persons with different functional brain asymmetry (as estimated from electrophysiological criteria) have different lymphocytic functional activities and rates of neuroimmune interactions.  相似文献   

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