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31.
Bronchopulmonary carcinoid tumors are tumors with a low malignant potential. They metastasize in 5-15% of cases. Accurate histologic preoperative prediction of the presence of regional lymph node metastases is not possible at this time. A retrospective quantitative pathologic analysis was performed to investigate the possibility of predicting the presence or absence of regional lymph node metastases in 24 patients with bronchopulmonary carcinoid tumors. The results of univariate analysis showed that large tumor size was associated significantly more frequently with regional lymph node metastases than small tumor size (P less than 0.01). The other quantitative features, ie, a larger mean nuclear area, higher standard deviation of the nuclear area and the presence of an aneuploid DNA index, were frequently associated with regional lymph node metastases, but this tendency was not significant. In multivariate analysis the combination of tumor size and mean nuclear area predicted the presence or absence of regional lymph node metastases correctly in 80 and 94% of the cases, respectively. These results indicate that the combination of tumor size and mean nuclear area may serve as a guideline to predict the presence of regional lymph node metastases.  相似文献   
32.
It has been shown that in the intact canine heart the left-ventricular end-systolic pressure/volume relation (ESPVR) depends on loading conditions: an increase in arterial vascular resistance causes a leftwards shift and a steeper slope of the ESPVR, suggesting an increased inotropic state. Our purpose was to investigate the possible contribution of the sympathetic nervous system to this load sensitivity of the ESPVR, using intact, but denervated, hearts with normal coronary perfusion and afterload. We used two types of loading intervention: venous volume infusion and gradual occlusion of the descending aorta. ESPVRs were obtained in six anaesthetized open-chest dogs, both before and after bilateral ablation of the stellate ganglia. To exclude the influence of heart rate changes, bilateral vagotomy was performed and the heart was paced. The absence of (unpaced) heart rate changes in response to pressure alterations was used to confirm total denervation. Left ventricular pressure was measured with a micromanometer and volume with a conductance catheter. ESPVRs were essentially linear and characterized by their slope (E es) and volume intercept at 12 kPa (V 12). We found that E es (P<0.0001) and V12 (P<0.05) were both significantly different during pressure and volume interventions (0.67±0.29 and 0.41±0.18 kPa/ml for E es and 16.2±8.2 and 18.2±8.4ml for V12 respectively). Denervation did not significantly affect the parameters of the ESPVR obtained by either volume infusion or aortic occlusion. Two-way analysis of variance revealed no significant interactive effect between denervation and intervention, indicating that the sympathetic nervous system does not influence the load dependency of the ESPVR. The dP/dt max: EDV relationship behaved similarly. These results suggest that load dependency is an intrinsic property of the myocardium.  相似文献   
33.
Primary congenital glaucoma (gene symbol: GLC3) is an ocular disorder that occurs for 0.01-0.04% of blind people. In the majority of familial cases reported so far, this condition is inherited as an autosomal recessive trait. We have recently used a group of 17 GLC3 families with a minimum of two affected offspring and consanguinity in most of the parental generation and mapped the first GLC3 locus (GLC3A) to the 2p21 region. Six families did not show any linkage to the GLC3A locus and thus provided evidence for genetic heterogeneity of this disorder. A total of eight families unlinked to the 2p21 region were used to search for the chromosomal location of the second GLC3 locus. Herein, we describe mapping of a new locus (designated GLC3B) for primary congenital glaucoma to the short arm of chromosome 1 (1p36.2-36.1) that is situated centromeric to the neuroblastoma and Charcot-Marie-Tooth type 2A (CMT2A) loci. A total of 17 DNA markers were genotyped from this region of chromosome 1. Four families showed no recombination with the two markers D1S2834 and D1S402 with a maximum lod score of 4.510 and 4.157 respectively. Pairwise and multipoint linkage analysis and inspection of the haplotypes revealed that the remaining four families are not linked to this part of chromosome 1, thus providing further evidence that at least one more locus for the autosomal recessive form of GLC3 must exist in the genome. Based on the recombination events, the overall linkage map of this region is: tel-D1S1192-D1S1635-D1S1193 - (D1S1597/-D1S489/D1S228)- [GLC3B/D1S2834/D1S402] - (D1S1176/D1S507/D1S407) - D1S2728-(MFAP2/D1S170) - D1S1368 - D1S436- D1S1592-cen.   相似文献   
34.
Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent.  相似文献   
35.
36.
Rhabdomyosarcoma (RMS) is a common malignancy in children, but embryonal rhabdomyosarcoma (ERMS) deposits rarely occur in the breast in adults. Therefore, little is known about magnetic resonance imaging (MRI) features of breast metastases from RMS, especially the embryonal type. We reported a case of a 22-year-old woman who was diagnosed with ERMS at left foot 2 years ago and accepted operation and chemotherapy. She was confirmed to have breast metastases from the left foot. Successive imaging examinations were performed 3 months apart. Breast ultrasound indicated a benign lesion, and further examination did not reveal any bone metastases. However, predominant restricted diffusion and rim contrast enhancement on MRI combined with the patient's medical history suggested a malignancy of BI-RADS 5. After 3 months, breast ultrasound revealed masses detected last time became larger and lobulated. In addition, internal heterogeneous intensity and rim contrast enhancement with restricted diffusion were revealed on MRI. We speculated that typical MRI findings of breast metastases from RMS may include iso- to hypointensity on T1WI, heterogeneous hyperintensity on T2WI, and circular enhancement with restricted diffusion. Moreover, mild peritumoral edema, rapid expansion of necrosis, and ascending time-intensity curve detected on MRI may be features of the ERMS type.  相似文献   
37.
Cytosolic glutathione S-transferases are a family of enzymes involved in the metabolism of drugs, toxins, carcinogens and also of anticancer drugs. Recent studies have indicated that glutathione S-transferases (GSTs) may play an important role in the resistance of cells to toxins and carcinogens but also to anticancer drugs. This report reviews the current literature concerning the role of glutathione S-transferases in anticancer drug resistance. Moreover, the significance of GST pi in carcinogenesis and its role as prognostic factor is discussed.  相似文献   
38.
Objective. The objective of our study was to determine if clinical observation of pressure-flow relationships (PFR) can differentiate between partial external obstruction (obstruction) and infiltration as a cause of poor performance of gravity-fed infusions.Methods. A total of 24 patients with functional intravenous cannulae in situ had obstruction simulated by the application of a tourniquet proximal to the cannula. The change in flow (F) for a discrete change in pressure (P) was determined in each case by counting drop rates at two different elevations of the fluid reservoir level, 10 cm apart. The same process was repeated in 15 patients in whom the cannula was in an extra vascular location (infiltration). Three sizes of cannula—16-gauge, 18-gauge, and 20-gauge—were examined, with equal distribution of sizes in each group. The effect on flow rates of inflating a blood pressure (BP) cuff proximally on the cannulated limb was assessed. The ratio P/F is the total resistance of the infusion system, and by subtracting known values for resistance of infusion tubing and cannula, the venous or tissue resistance was calculated.Results. There was a statistically significant difference between the change in flow for obstructed compared with infiltrated cannulae for the same change in pressure for each cannula size. The mean venous resistance was 23 mm Hg/L/hr, while that of tissue was 280 mm Hg/L/hr, with no overlap between groups. There was no effect on flow rate with blood pressure cuff inflation in the infiltrated group whereas flow progressively fell in the obstructed group.Conclusions. Clinical observation of PFRs in poorly functioning gravity-fed IV infusions can assist in detecting infiltration as a cause. Inflation of a blood pressure cuff will further impair flow where the cannula is intravascular, but will have no effect in an extravascular location.  相似文献   
39.
Reconstructive surgery for ulcerative colitis and familial adenomatous polyposis nowadays usually takes the form of an ileoanal pouch, involving making a reservoir of the terminal portion of the ileum which subsequently is anastomosed to the anal canal. This method results in definite cure in many cases, but is associated with a morbidity of 15-30% and fails in 10%. A new surgical treatment includes complete removal of the affected large bowel mucosa, guaranteeing oroanal intestinal continuity, limiting complications and providing good function of the reservoir or of the new rectum. In creation of an ileoneorectal anastomosis, complete removal of the affected mucous membrane is followed by preparing a functional 'neorectum' by means of pedicle grafting of ileal mucous membrane on to the uncovered muscular wall of the rectum. This operation gave good results in a small-scale clinical trial.  相似文献   
40.
PURPOSE: To study the systemic effects of topically applied 5% phenylephrine. To investigate intraoperative injection of epinephrine in the anterior chamber as an alternative. METHOD: 75 patients undergoing cataract surgery were randomized into three groups. In group 1, the pupil was dilated using topically 5% phenylephrine and 1% cyclopentolate, the patients blocked the lacrimal drainage system themselves by digital compression. Group 2 received the same drops, digital compression was performed by one of the investigators. In Group 3, no preoperative phenylephrine was used--instead, epinephrine 1:25,000 was injected in the anterior chamber at the beginning of surgery. Retrobulbar anesthesia was performed in a short narcosis with ketamine and propofol. RESULTS: Mean preoperative blood pressure values were higher than the day before. They fell during narcosis, to increase significantly after the injection of the local anesthetics. At the beginning of surgery they were back to prenarcotic values. Intraoperative blood pressure remained stable. Preoperative day values were found two hours postop. There was no significant difference in the circulatory behavior between the three groups. For mydriasis, intraoperative intracameral epinephrine was not as effective as preoperative phenylephrine. CONCLUSION: In normotonic or medically treated arterial hypertensive patients, preoperative mydriasis using 5% phenylephrine is safe--proceeding the way described above. Compression of the lacrimal drainage system can be performed by the patients effectively. Intraoperative intracameral epinephrine does not replace preoperative phenylephrine.  相似文献   
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