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81.
There is disagreement over the HLA-DR associations of Hashimoto's (goitrous) thyroiditis. We have studied 86 English Caucasian patients with this condition whose DR types were determined by restriction fragment polymorphism analysis. HLA-DR3 was significantly more frequent in these patients than in 100 controls (chi 2 = 7.09; P less than 0.01). The relative risk was 2.23 and aetiological fraction 0.29. HLA-DPB and DQB alleles were analysed in a proportion of these subjects by enzymatic DNA amplification and oligonucleotide probing. The only significant finding was an excess of HLA-DQw2 (in linkage disequilibrium with DR3) in the Hashimoto group (chi 2 = 7.43, P less than 0.007). These results do not support a difference between goitrous and atrophic thyroiditis based on respective associations with HLA-DR5 and DR3, but confirm a recent study in which HLA-DR3 was associated with Hashimoto's thyroiditis. However, it is possible that genes telomeric to DR3 may be involved in determining which type of thyroiditis a patient with autoimmune hypothyroidism develops.  相似文献   
82.
83.
The microcirculatory architecture of normal tissue, transitional mucosa and adenocarcinoma of the human colon was investigated with microvascular corrosion casting (MVCC) combined with scanning electron microscopy (SEM). The study showed that the capillaries within the normal mucosa were arranged in a regular hexagonal pattern around the mucosal glands and that the microvessels of transitional mucosa mostly had lost the typical hexagonal pattern and become slightly wider in diameter. The microvessels in the tumor periphery were increased in number and disorganized, and presented large variation in morphology with claw-like formations, widened sinuses, diverticula and appendixoid patterns. Microvessels were lacking in the central areas of tumors. These morphological alterations may serve as additional indicators of tumor development.  相似文献   
84.
Immunology     
A selection of interesting papers that were published in the two months before our press date in major journals most likely to report significant results in immunology.  相似文献   
85.
Quantitative receptor autoradiography was used to study possible alterations of the densities of multiple serotonin (5-HT) receptor subtypes and of serotonin transporter in the brain of 5-HT(2C) receptor knockout mice. The radioligands employed were [(3)H]citalopram, [(3)H]WAY100,635, [(3)H]8-OH-DPAT, [(3)H]GR125743, [(3)H]sumatriptan, [(3)H]MDL100,907, [(125)I](+/-)DOI, [(3)H]mesulergine, [(3)H]5-HT, [(3)H]GR113808, and [(3)H]5-CT. As expected, radioligands that label 5-HT(2C) receptors showed a complete absence of labeling in mutant mice choroid plexus and significantly reduced densities in other brain regions expressing 5-HT(2C) receptors. With the rest of the radioligands, no significant alterations in the densities of labeled sites were found in any brain region. In situ hybridization showed no changes in 5-HT(2A) receptor and serotonin transporter mRNA levels, whereas 5-HT(2C) receptor mRNA levels were reduced in certain brain regions. The present results indicate that the mouse serotonergic system does not exhibit compensatory up- or down-regulation of the majority of its components (serotonin transporter and most 5-HT receptor subtypes) in response to the absence of 5-HT(2C) receptors.  相似文献   
86.
对16例垂体腺瘤采用单侧鼻前庭切口经蝶切除,效果满意,既可减少手术创伤,又缩短了手术距离,且避免了美容缺陷,是一种设计巧妙,较为实用的手术方法,尤其适用于生长激素腺瘤。  相似文献   
87.
The theoretical model for perfusion measurement by NMR using arterial labeling of endogenous water is extended to include the effects of transit time and cross-relaxation of tissue water with macromolecules. Water magnetization in rat brain is monitored using the STEAM method to simultaneously determine the transit time, magnetization transfer rate constant, and perfusion. The results show that the transit time in rat brain is quite short, and thus its effect on perfusion measurement is small. It is also demonstrated both theoretically and experimentally that the steady-state effects of cross-relaxation with macromolecules on perfusion measurement are accounted for by a proper control experiment.  相似文献   
88.
The effects of platelet-derived growth factor (PDGF) on phospholipase D (PLD) activity and deoxyribonucleic acid (DNA) synthesis in rat C6 glioma cells have been investigated. Pretreatment of serum-starved C6 cells with PDGF results in enhanced choline production and the phosphatidylethanol (PEt) formation in the presence of ethanol, indicating the activation of PLD acting on phosphatidylcholine (PC). The dose-response curve for choline generation and DNA synthesis were comparable. In addition, the effects of PDGF on both PEt formation and [3H]thymidine incorporation into acid-precipitable material was blocked by the potent protein kinase C (PKC) inhibitor 1-(5-isoquinolinesulphonyl)-2-methylpiperazine (H-7) but not by N-(2-guanidinoethyl)-5-isoquinolinesulphonamide (HA1004), a relatively weak inhibitor of PKC, suggesting that PDGF plays an important role as a positive regulator of glioma cell growth via a PLD-mediated mitogenic signal transduction cascades, which depends largely on the activation of PKC.  相似文献   
89.
检测了74例正常足月妊娠妇女和56例妊娠期肝内胆汁淤积症(ICP)患血清甘胆酸(CG)的浓度,结果ICP患血CG浓度显升高(13.52±9.54mg/L),为正常孕妇(2.67±1.92mg/L)的5~10倍,根据血CG浓度将ICP患分为〈10、10~20,〉20mg/L3组,将3组胎儿出生情况与正常组相对照,结果显示血CG浓度〈10mg/L组羊水胎粪污染率及新生儿窒息率与正常组无差异,而  相似文献   
90.
PURPOSE: During clinical monitoring, vecuronium appeared to reduce the rapidly extracted auditory evoked potentials index (A-line ARX index or AAI) to some extent. A prospective and randomized study was designed to analyze this phenomenon. METHODS: Forty adult patients undergoing elective surgery were studied. After tracheal intubation, anesthesia was maintained with an end-tidal isoflurane concentration (F(ET)ISO) of 1.0% for 20 min, then a 10-mL dose of either vecuronium 0.05 mg*kg(-1), 0.1 mg*kg(-1), 0.2 mg*kg(-1) or saline was administered in a randomized, double-blind design. The AAI and bispectral index (BI(hx)) were monitored throughout the study and analyzed off-line. RESULTS: BI(hx) was unaltered after the administration of saline or vecuronium. The mean of the averaged (per patient) AAI values recorded from two minutes to ten minutes after the administration of saline or vecuronium 0.05 mg*kg(-1) did not differ significantly from the corresponding mean recorded from 15 min to 20 min after F(ET)ISO maintained 1.0% (P = 0.678, 0.169), however after the administration of vecuronium 0.1 mg*kg(-1) or 0.2 mg*kg(-1), AAI was reduced from 18.3, 18.0 to 14.8, 13.4 (P = 0.016, 0.017). CONCLUSIONS: Neuromuscular block with vecuronium reduces AAI in patients during steady state anesthesia without surgical stimuli, while BI(hx) is unaltered. The cut-off values of AAI for events should be determined according to the level of neuromuscular blockade when monitoring the depth of anesthesia/sedation.  相似文献   
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