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91.
Tissue microarrays have been created from 326 lung tumours, including 173 squamous cell carcinomas (SCCs) and 132 adenocarcinomas (ADs). In order to evaluate the usefulness of this microarray series, the expression of p53, p16, and Rb proteins was compared by immunohistochemistry on both the tissue microarrays and the corresponding whole sections for all 326 tumours. The presence of replicate punches improved both the yield and the concordance of data relative to the whole section results, so that the consensus score from the replicates agreed with the whole section result in more than 90% of informative tumours. The large number of tumours in this series also allowed significant differences in protein expression patterns to be detected between SCC and AD, the major subtypes of non-small cell lung carcinoma (NSCLC). SCC had higher levels of p53 staining (67% vs 52% in AD) and substantially increased p16 loss (SCC 75%, AD 53%) combined with greater retention of pRB expression (SCC 86% vs 67% in AD). The strong inverse correlation between p16 and pRB seen in SCC was essentially absent in AD. This study represents the largest single immunohistochemical survey of protein expression for p53, p16, and RB in NSCLCs.  相似文献   
92.
Lakhal B, Braham R, Berguigua R, Bouali N, Zaouali M, Chaieb M, Veitia RA, Saad A, Elghezal H. Cytogenetic analyses of premature ovarian failure using karyotyping and interphase fluorescence in situ hybridization (FISH) in a group of 1000 patients. To evaluate the implication of chromosome abnormalities in the etiology of premature ovarian failure (POF), 1000 patients with POF recruited at the Department of Cytogenetics of Farhat Hached Hospital (Sousse, Tunisia) between January 1996 and December 2008. Chromosome analyses were performed by using karyotyping and interphase fluorescent in situ hybridisation (FISH) using a centromeric probe of the chromosome X to look for low‐level mosaicism of X‐chromosome monosomy. Hundred and eight chromosomal abnormalities (10.8%) were found using karyotype analysis. Anomalies were detected in 61 cases out of 432 primary amenorrhea patients (14.12%) and 47 cases out of 568 secondary amenorrhea patients (8.27%). In 23 POF patients among 200 (11.5%) with 46,XX normal karyotype and explored using interphase FISH analysis, the percentage of cells with X‐chromosome monosomy was significantly higher as compared with controls in the same age. The cytogenetic study of POF patients showed a high prevalence of chromosome anomalies either in primary or in secondary amenorrhoea. Mosaic X‐chromosome s aneuploïdy was the most frequent abnormality and some patients with POF may be attributable to low‐level 45,X/46,XX mosaicism detectable using FISH analysis.  相似文献   
93.
Seventy-five patients with resistant acute leukemia or lymphoma received high-dose cyclophosphamide and etoposide to explore the activity of this combination in resistant hematologic malignancies, and to determine the maximum doses of these drugs that can be combined without bone marrow transplantation. Etoposide was administered over 29 to 69 hours by continuous infusion corresponding to total doses of 1.8 g/m2 to 4.8 g/m2. Cyclophosphamide, 50 mg/kg/d, was administered on 3 or 4 consecutive days total 150 to 200 mg/kg ideal body weight). At all dose levels myelosuppression was severe but reversible. Mucosal toxicity was dose-limiting with the maximum tolerated dose level combining etoposide 4.2 g/m2 with cyclophosphamide 200 mg/kg. Continuous etoposide infusion produced stable plasma levels that were lower than would be achieved after administration by short intravenous infusion, and this could explain our ability to escalate etoposide above the previously reported maximum tolerated dose. There were 28 complete (35%) and 12 partial (16%) responses. Median duration of complete response (CR) was 3.5 months (range 1.1 to 20+). Seventeen of 40 patients (42%) with acute myelogenous leukemia (AML) achieved CR, including 6 of 20 (30%) with high-dose cytosine arabinoside resistance. We conclude that bone marrow transplantation is not required after maximum tolerated doses of etoposide and cyclophosphamide. This regimen is active in resistant hematologic neoplasms, and the occurrence of CR in patients with high-dose cytosine arabinoside-resistant AML indicates a lack of complete cross-resistance between these regimens.  相似文献   
94.
A specially designed rotational viscometer was used to investigate the effects of the antiplatelet agent PGI2 in combination with theophylline on the response of human platelets subjected to shear stress. Samples of citrated platelet-rich plasma (PRP) were exposed to shear stress in the viscometer for a period of 5 min at 23 degrees C. The levels of stress studied ranged from 50 to 300 dynes/sq cm. Pretreatment of the platelets with 0.01 microM PGI2 and 500 microM theophylline before exposure to shear stress caused a large reduction in shear-induced platelet aggregation. However, it was also observed that the PGI2-- theophylline pretreatment concomitantly caused a large increase in shear-induced platelet lysis and serotonin release at stress levels equal to or greater than 150 dynes/sq cm. This observed increase in platelet fragility may have important implications for clinical applications of PGI2. The results are discussed and compared to those obtained in prior work in which platelets were pretreated with acetylsalicylic acid or with PGE1.  相似文献   
95.
Ingraham  LM; Boxer  LA; Haak  RA; Baehner  RL 《Blood》1981,58(4):830-835
We have studied membrane fluidity changes in polymorphonuclear leukocytes (PMN) during phagocytosis. Membrane fluidity was assessed by electron spin resonance (ESR) using a nitroxide-substituted stearic acid analog (5DS) as a spin probe. PMN from normal subjects and from 3 CGD patients (2 males, 1 female) were incubated in Kreb's Ringers phosphate with or without opsonized zymosan. ESR spectra were obtained and the order parameter (S), which is inversely related to membrane fluidity, was calculated. Without zymosan addition, S for normal (0.638) and for CGD (0.635) were not significantly different (p less than 0.35). The S values indicate that under resting conditions the molecular environment of the CGD membrane is similar to that of normal PMN membranes. However, with addition of opsonized zymosan, the normal, but not the CGD, PMN showed a significant increase (CGD, S = 0.638; normal, S = 0.647; p less than 0.001). This change in S for the normals is consistent with a more restricted movement of 5DS. Treatment of normal PMN with a mixture of scavengers specific for H2O2 (catalase, 1600 U/ml), O2-.(superoxide dismutase, 100 micrograms/ml), and for HO., (sodium benzoate, 1mM) during zymosan stimulation gave S values similar to those of resting cells. Catalase alone also lowered S value, suggesting that H2O2 was instrumental in causing the initial S value increase. This idea was supported by studies in which CGD cells were incubated with zymosan in the presence of glucose oxidase, an enzyme that catalyzes glucose oxidation resulting in the direct reduction of molecular oxygen to H2O2. Our results indicate that reduced O2 by- products, particularly H2O2, can cause altered biophysical properties of PMN membrane during phagocytosis.  相似文献   
96.
Oculocutaneous albinism   总被引:2,自引:0,他引:2  
Oculocutaneous albinism represents a group of inherited skin disorders characterized by a generalized reduction of cutaneous, ocular and pilar pigmentation from the time of birth. Oculocutaneous albinism types 1 and 2 are the most common, but several other types have been described. A defect in the melanin synthesis pathway, resulting in reduced formation of melanin, is responsible for oculocutaneous albinism. Aetiology, clinical manifestations, diagnosis and management are discussed.  相似文献   
97.

Background

Thirty-day readmission post-bariatric surgery is used as a metric for surgical quality and patient care. We sought to examine factors driving 30-day readmissions after laparoscopic sleeve gastrectomy (LSG).

Methods

We reviewed 1257 LSG performed between March 2012 and June 2014. Readmitted and nonreadmitted patients were compared in their demographics, medical histories, and index hospitalizations. Multivariable regression was used to identify risk factors for readmission.

Results

Forty-five (3.6 %) patients required 30-day readmissions. Forty-seven percent were readmitted with malaise (emesis, dehydration, abdominal pain) and 42 % with technical complications (leak, bleed, mesenteric vein thrombosis). Factors independently associated with 30-day readmission include index admission length of stay (LOS) ≥3 days (OR 2.54, CI?=?[1.19, 5.40]), intraoperative drain placement (OR 3.11, CI?=?[1.58, 6.13]), postoperative complications (OR 8.21, CI?=?[2.33, 28.97]), and pain at discharge (OR?8.49, CI?=?[2.37, 30.44]). Patients requiring 30-day readmissions were 72 times more likely to have additional readmissions by 6 months (OR?72.4, CI?=?[15.8, 330.5]).

Conclusions

The 30-day readmission rate after LSG is 3.6 %, with near equal contributions from malaise and technical complications. LOS, postoperative complications, drain placement, and pain score can aid in identifying patients at increased risk for 30-day readmissions. Patients should be educated on postoperative hydration and pain management, so readmissions can be limited to technical complications requiring acute inpatient management.
  相似文献   
98.
The authors report 2.5 years' experience with the use of cytomegalovirus (CMV)-seronegative blood components for the prevention of primary CMV infection after allogeneic marrow transplantation from seronegative marrow donors to 104 CMV-seronegative patients. Patients and blood donors were screened for CMV-seronegativity by a combination of passive latex agglutination, complement fixation, and indirect hemagglutination CMV antibody screening methods. Changes in blood banking procedures necessary to provide CMV-seronegative components are detailed. Providing CMV-seronegative components was a considerable undertaking; a mean, per patient, of 19 units of red cells and 105 units of platelets was required. Twenty percent of the platelet support was provided by family members and 80 percent by volunteer donors. CMV-infection was eliminated in all but one patient not considered infected at the time of transplantation. The capability to provide CMV-seronegative components depends on an adequate supply of seronegative donors, a sensitive and practical screening method for CMV antibody, a major commitment by the blood bank, and close communication between the blood bank and the patients' physicians.  相似文献   
99.
Six men were studied to compare the effects of pre-exercise carbohydrate feedings on endurance performance and muscle glycogen utilization during prolonged exercise. Trials consisted of a cycling ride to exhaustion at 75% maximal oxygen uptake preceded by the ingestion of either 75 g of glucose in 350 ml of water (GLU), 75 g of fructose in 350 ml of water (FRU), or 350 ml of an artificially sweetened and flavored placebo (CON). No differences were observed between trials for oxygen uptake, respiratory exchange ratio, heart rate, or exercise time to exhaustion (CON = 92.7 +/- 5.2 min, FRU = 90.6 +/- 12.4, and GLU = 92.8 +/- 11.3, mean +/- SE). Blood glucose was elevated as a result of the GLU feeding, but fell rapidly with the onset of exercise, reaching a low of 4.02 +/- 0.34 mmol X l-1 at 15 min of exercise. Serum insulin also increased following the GLU feeding but had returned to pre-drink levels by 30 min of exercise. No differences in blood glucose and insulin were observed between FRU and CON. Muscle glycogen utilization during the first 30 min of exercise (CON = 46.3 +/- 8.2 mmol X kg-1 wet weight, FRU = 56.3 +/- 3.0 mmol X kg-1 wet weight, GLU = 50.0 +/- 4.9 mmol X kg-1 wet weight) and total glycogen use (CON = 93.4 +/- 11.1, FRU = 118.8 +/- 10.9, and GLU = 99.5 +/- 4.3) were similar in the three trials.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
100.
Elastic recoil of the vessel wall is a common cause of failure of percutaneous transluminal angioplasty in renal arteries. To oppose such recoil, balloon-expandable metal stents were implanted in artificially stenotic renal arteries in pigs and normal renal arteries in dogs and pigs. The stents were then examined angiographically and histologically at regular intervals. All stents were completely covered with endothelialized neointima in 3 weeks. There was no difference in intimal thickness between the stenotic and nonstenotic renal arteries. A large stent diameter and a large open or nonmetal surface may cause less intimal hyperplasia, but nonturbulent, fast arterial flow is probably the most important factor in ensuring long-term patency of the vessel.  相似文献   
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