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排序方式: 共有7584条查询结果,搜索用时 15 毫秒
31.
Detection of frequent allelic loss on proximal chromosome 17q in sporadic breast carcinoma using microsatellite length polymorphisms. 总被引:20,自引:0,他引:20
P A Futreal P S?derkvist J R Marks J D Iglehart C Cochran J C Barrett R W Wiseman 《Cancer research》1992,52(9):2624-2627
Analyses of losses of heterozygosity and linkage studies have implicated a gene(s) on chromosome 17q in the genesis of sporadic and early-onset familial breast carcinomas, respectively. To define the critical region of 17q, we examined DNAs from a series of 20 sporadic breast carcinomas and corresponding blood samples for allelic losses of chromosome 17q using microsatellite length polymorphisms. With these highly informative markers (average heterozygosity, 0.73), we observed frequent deletions of 17q at several loci. We found that D17S250 was deleted in 50% (7 of 14), THRA1 in 79% (11 of 14), D17S579 in 59% (11 of 19), NME1 in 29% (5 of 17), MPO in 36% (4 of 11), and GH in 25% (4 of 16) in the tumor set examined. A common region of deletion was found that was flanked by D17S250 to D15S579. These markers have recently been localized to a 6-cM interval of proximal chromosome 17q in bands 17q11.2-q21 and map within the region of the early-onset familial breast cancer locus, implying that the same gene or genes may be involved in both sporadic and familial breast tumors. Thyroid hormone receptor alpha and retinoic acid receptor alpha are two potential candidate genes in this region. 相似文献
32.
Mini-Mental State Examination (MMSE) scores were studied in an ambulatory elderly population to identify correlates with self-reported signs, symptoms, diseases, drugs and laboratory values. A total of 1,264 subjects were studied including 844 women and 420 men. In this study, 5.0% of men and 5.3% of women scored less than 24 on the MMSE. A linear-regression model revealed eleven factors of significance in predicting scores on the MMSE. The most important predictors were age (p less than 0.0001), self-reported memory loss (p less than 0.0001), complaints of swollen feet or ankles (p less than 0.0010), the total number of diseases reported (0.0006) and the serum lactate dehydrogenase concentration (p less than 0.0098). Results suggest that cognitive function in the elderly is not related to the general level of health or consistently affected by specific disease states. 相似文献
33.
Marks K; Kilav R; Berman E; Naveh-Many T; Silver J 《Nephrology, dialysis, transplantation》1997,12(8):1581-1585
Background: The murine analogue of X-linked
hypophosphateaemia is the Hyp mouse; it has chronic
phosphate depletion from an inherited defect of renal tubular reabsorption.
Phosphate directly regulates the parathyroid (PT) in normal rats and it is
of interest whether this regulation is intact in Hyp
mice. Methods: Hyp mice were fed
either a low-phosphate diet or control diet and PTH mRNA levels were
measured. In addition changes in NMR-visible kidney and muscle
intracellular phosphate potentials in normal and Hyp
mice were determined. Mice were maintained on a low-phosphate (0.02%) or
normal-phosphate (0.6%) diet for 24 and 72 h. Results:
On the normal diet, Hyp mice had hypophosphataemia,
normocalcaemia, and normal PTH mRNA levels. Phosphate deprivation for 72 h
led to a profound fall in plasma phosphate, a slight but significant rise
in plasma calcium, and a dramatic decrease in PTH mRNA, similar to that of
normal mice fed this diet. Changes in kidney and muscle intracellular
phosphate measured by NMR spectroscopy were not affected by diet or
genotype. Conclusion: Dietary phosphate deprivation
decreased Hyp mice PTH mRNA levels and caused no
change in intracellular phosphate potentials. Therefore
Hyp mice parathyroids' adapt appropriately to
phosphate deprivation albeit at a lower threshold compared to normal mice. 相似文献
34.
Diagnosis and treatment of sacral and retrorectal tumors. I 总被引:1,自引:0,他引:1
35.
缺血性卒中或短暂性脑缺血发作患者的卒中预防指南 总被引:8,自引:0,他引:8
Ralph L.Sacco Robert Adams Grge Albers Mark J.ALBERTS Oscar Benavente Karen Furie Larry B.Goldstein Philip Gorelick Jonathan Halperin Robert Harbaugh S.Claiborne Johnston Irene Katzan Margaret Kelly-Hayes Edgar J.Kenton Michael Marks Lee H.Schwamm Thomas Tomsick 曹勇军 《中华脑血管病论坛》2006,4(1):21-66
这份新声明旨在为缺血性卒中或短暂性脑缺血发作存活者的缺血性卒中预防提供全面和及时的循证推荐,循证推荐包括对危险因素的控制,动脉粥样硬化性疾病的干预措施,心源性栓塞的抗栓治疗以及非心源性卒中抗血小板药的应用。另外,还为其他多种特殊情况下复发性卒中的预防提供了推荐、包括动脉夹层分离、卵圆孔未闭、高同型半胱氨酸血症、高凝状态、镰状细胞病、脑静脉窦血栓形成、女性卒中(特别是与妊娠和绝经后激素替代治疗相关卒中),脑出血后肮凝药的应用,以及该指南在高危人群中执行和应用的特殊措施。 相似文献
36.
Thirty-one patients underwent a negative second-look laparotomy between 1976 and 1986. Fourteen patients received intraperitoneal chromic phosphate (P-32) after a negative second-look laparotomy. There has been no local recurrence (zero of 14) and no deaths attributable to recurrent disease. Local control and disease-free survival are 100%, with a minimum follow-up of 2 years and a mean follow-up of 4 years. Seventeen patients received no further therapy because of patient refusal, poor diffusion, or other contraindications to P-32 installation. Four of 17 patients undergoing negative second-look procedures without the addition of P-32 have subsequently recurred. This difference is highly suggestive (P = .076). There have been no major complications with the addition of P-32. The use of intraperitoneal P-32 after negative second-look laparotomies on ovarian carcinoma is well tolerated and effective in preventing recurrence. 相似文献
37.
A comprehensive anatomic and radiographic analysis of the peribursal fat plane in 12 cadavers confirmed that the fat plane seen on radiographs represents extrasynovial fat lining the subacromial bursa and documented the anatomic relations of the bursa. A three-part retrospective clinical evaluation of rotator cuff tears, calcific tendinitis, and rheumatoid arthritis was performed. Two osteoradiologists blindly graded the appearance of the peribursal fat plane with the shoulder in external versus internal rotation in 21 patients with arthrographically intact rotator cuffs and 21 patients with disrupted rotator cuffs. The peribursal fat plane was seen better with disrupted rotator cuffs. The peribursal fat plane was seen better with the shoulder in internal rotation and was seen in 60% of control subjects but only 21% of patients with rotator cuff tears. Partial or complete obliteration of this fat plane is a sensitive (79%) but less specific (60%) indicator of rotator cuff tears. Obliteration of the peribursal fat plane by inflammatory processes in adjacent tissues, including calcific tendinitis and rheumatoid arthritis, occurred with a high frequency. 相似文献
38.
Studies on the endogenous flora of the human breast 总被引:1,自引:0,他引:1
Identification of the endogenous microbiological flora of the human breast and its role in breast infections following subglandular augmentation or reduction mammaplasty was undertaken. A total of 231 cultures were performed on 59 breasts in 30 patients. Patients were followed for 12 months. No fungus was cultured from any specimen. Of the breasts cultured 53% were positive for coagulase-negative staphylococcus. Other aerobes found included diphtheroids, lactobacillus, D-enterococcus, micrococcus, and alpha-hemolytic streptococcus. Propionibacterium acne was the most frequent anaerobic bacteria cultured. Other anaerobes included peptococcus and clostridium sporogenes. There was no correlation with respect to the type of bacterium and the depth within the breast where the culture specimens were taken. Postoperative wound infections developed in 2 of 19 patients undergoing reduction mammaplasty. Bacteria identical to those cultured at the time of surgery were again cultured from the wound. Twenty subglandular augmentation mammaplasties were performed with a 25% capsular rate at one year. Two capsules were associated with no bacterial growth at the time of mammaplasty surgery, whereas three were associated with coagulase-negative staphylococcus, Propionibacterium acne, and diphtheroids, respectively. Of the 15 breasts with no capsular contracture after one year, operative culture revealed coagulase-negative staphylococcus in 8 and no bacterial growth in 7. Even breast tissue located deep within the gland away from the nipple contains a flora that is similar to that of normal skin. Cases of infection in which the endogenous bacteria were correlated with later infection was documented. 相似文献
39.
Blood-injury phobia: a review 总被引:2,自引:0,他引:2
I Marks 《The American journal of psychiatry》1988,145(10):1207-1213
Natural human uneasiness about blood, injury, or deformity sometimes becomes a specific phobia, which can lead to serious disability if vital medical procedures are refused. Blood-injury phobia usually starts in childhood and is often familial. Unlike other phobic cues, which cause persistent tachycardia, blood-injury phobic cues evoke an initial rise in heart rate followed by vasovagal bradycardia and, frequently, syncope. Although blood-injury phobia may have an evolutionary, genetic, and physiological basis, it can be treated effectively by exposure. The tendency to faint early in exposure therapy can be reduced by lying down, tensing the muscles, or inducing anger. 相似文献
40.
M P Marks H Chee R P Liddell G K Steinberg N Panahian B Lane 《AJNR. American journal of neuroradiology》1994,15(5):821
PURPOSETo evaluate mechanically detachable coil designs capable of controlled and instantaneous release within an aneurysm or vascular space.METHODSThree mechanically detachable coil designs, clamped ball, looped ribbon, and interlocking cylinder, were evaluated using in vitro and in vivo testing to study reliability of coil release, retractability, and coil behavior in a microcatheters. In vitro tests were performed using a glass side-wall aneurysm model and conventional microcatheters. In vivo experiments in rabbits included aneurysm models (side-wall and bifurcation) and arterial occlusions (carotid and renal).RESULTSAll three designs deployed coils easily and were able to retract coils after partial deployment. Motion was seen in previously released coils and in the catheter when using the clamped ball and looped ribbon designs. The interlocking cylinder design did not cause similar motion. When compared with the other two designs, the interlocking cylinder had significantly greater separation forces between coil pusher and coil while in the catheter. Frictional forces within the catheter were lower for the interlocking cylinder mechanically detachable coil design than for a commercially available conventional coil and coil pusher system. During in vivo testing, the mechanically detachable coil design operated smoothly in the catheter, providing good release and retraction in aneurysms and straight vessels.CONCLUSIONThe interlocking cylinder mechanically detachable coil design is superior to the other two tested designs. The mechanically detachable coil was reliably delivered and detached in in vivo testing for the treatment of aneurysms and for the occlusion of blood vessels. 相似文献