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71.
The distribution of carcinoembryonic antigen (CEA), organ specific colonic antigen (C) and two pepsinogens (P) was studied in the peritumorous mucosa and in the tumours (one carcinoid and 3 adenomas) in the stomach of a patient, that had undergone the Bilroth-II resection 10 years before. No antigens were found in the carcinoid. C-antigen was found in the adenomas. The peritumorous gastric mucosa, morphologically not changed contained P, but not C and CEA. Mucosal areas adjacent to the adenomas had dysplastic or metaplastic changes, contained CEA and C, but didn't contain P.  相似文献   
72.
Clinico-roentgeno-morphological investigation established a marked regression of tumor in as many as 86.1% out of 230 patients with stage IIB and III breast cancer who had undergone radiothermotherapy. Morphologically confirmed complete regression was observed in 12.6% of patients with lesions smaller than 3 cm in diameter at presentation. Treatment was followed by massive necrosis, dystrophic changes and inhibition of mitotic activity of tumor cells in patients with stage III cancer and those with stage IIB who had presented with tumors larger than 3 cm in diameter. However, in all these cases viable tumor cells were still observed at the periphery of tumor.  相似文献   
73.
Blood warming: current applications and techniques   总被引:5,自引:0,他引:5  
Active blood warming is a recent practice and arises out of conflicting needs. On the one hand, the safety and preservation of blood require refrigerated storage and delivery up to the moment of transfusion. On the other hand, modern methods of very rapid transfusion in resuscitation would cause clinically dangerous hypothermia if unmodified, ice-cold blood were to be so transfused. These needs must be reconciled in the interest of adequate patient care--hence the need for blood warming. Nevertheless, blood warming creates risks of its own and should not be used without justifying clinical indications. Within limits that extend somewhat above normal body temperature, the application of heat does no harm to stored RBC, a fact that is not reflected in current standards for blood warmers. Bearing in mind the human tendency to "stretch" standards and the fallibility of mechanical devices, caution is always wise. But perhaps the time has come for reconsideration of the present upper limit of 38 degrees C. Many varieties of blood warmers are available in the US, but none at this time is based on electromagnetic activity. The most common systems now in use are in-line warmers, most of which are not adequate for the type of rapid-transfusion systems currently available. Countercurrent in-line blood warmers and the method of rapid warm saline admixture can both be used successfully for rapid, massive transfusions. Blood warming is seldom necessary or desirable for elective transfusions at conventional rates, even for patients with cold autoagglutinins.  相似文献   
74.
The perforator-based flaps in the sacral and ischial region is designed according to the localization of perforators that penetrate the gluteus maximus muscle, reach the intra-fascial and supra-fascial planes with the overlying skin forming a rich vascular plexus. The perforator-based flaps described in this article are highly vascularized, have minimal donor site morbidity, and do not require the sacrifice of the gluteus maximus muscle. In a period between April 2008 and March 2009, six patients with sacral pressure sore were reconstructed with propeller flap method based on superior gluteal and parasacral artery perforators. One flap loss was noted. Three cases of ischial pressure sore were reconstructed with longitudinal propeller flap cover, based on inferior gluteal artery perforator. One flap suffered wound infection and dehiscence. Two cases of pilonidal sinus were reconstructed with propeller flap based on parasacral perforators. Both the flaps survived without any complications. Donor sites were closed primarily. In the light of this, they can be considered among the first surgical choices to re-surface soft tissue defects of the sacral and ischial regions. In the series of 11 patients, two patients (18%) suffered complications.  相似文献   
75.
Background: Evidence‐based treatment protocols including therapeutic hypothermia have increased hospital survival to over 50% in unconscious out‐of‐hospital cardiac arrest survivors. In this study we estimated the incidence of cognitive dysfunctions in a group of cardiac arrest survivors with a high functional outcome treated with therapeutic hypothermia. Secondarily, we assessed the cardiac arrest group's level of cognitive performance in each tested cognitive domain and investigated the relationship between cognitive function and age, time since cardiac arrest and health‐related quality of life (HRQOL). Methods: We included 26 patients 13–28 months after a cardiac arrest. All patients were scored using the Cerebral Performance Category scale (CPC) and Mini‐Mental State Examination (MMSE). Twenty‐five of the patients were tested for cognitive function using the Cambridge Neuropsychological Test Automated Battery (CANTAB). These patients were tested using four cognitive tests: Motor Screening Test, Delayed Matching to Sample, Stockings of Cambridge and Paired Associate Learning from CANTAB. All patients filled in the Short Form‐36 for the assessment of HRQOL. Results: Thirteen of 25 (52%) patients were classified as having a cognitive dysfunction. Compared with the reference population, there was no difference in the performance in motor function and delayed memory but there were significant differences in executive function and episodic memory. We found no associations between cognitive function and age, time since cardiac arrest or HRQOL. Conclusion: Half of the patients had a cognitive dysfunction with reduced performance on executive function and episodic memory, indicating frontal and temporal lobe affection, respectively. Reduced performance did not affect HRQOL.  相似文献   
76.
77.
PurposeTo characterize a tumor model containing a hypoxia-inducible reporter gene and to demonstrate utility by comparison of reporter gene expression to the uptake and distribution of the hypoxia tracer 18F-fluoromisonidazole (18F-FMISO).MethodsThree tumors derived from the rat prostate cancer cell line R3327-AT were grown in each of two rats as follows: (1) parental R3327-AT, (2) positive control R3327-AT/PC in which the HSV1-tkeGFP fusion reporter gene was expressed constitutively, (3) R3327-AT/HRE in which the reporter gene was placed under the control of a hypoxia-inducible factor-responsive promoter sequence (HRE). Animals were coadministered a hypoxia-specific marker (pimonidazole) and the reporter gene probe 124I-2′-fluoro-2′-deoxy-1-β-d-arabinofuranosyl-5-iodouracil (124I-FIAU) 3 h prior to sacrifice. Statistical analysis of the spatial association between 124I-FIAU uptake and pimonidazole fluorescent staining intensity was then performed on a pixel-by-pixel basis.Utility of this system was demonstrated by assessment of reporter gene expression versus the exogenous hypoxia probe 18F-FMISO. Two rats, each bearing a single R3327-AT/HRE tumor, were injected with 124I-FIAU (3 h before sacrifice) and 18F-FMISO (2 h before sacrifice). Statistical analysis of the spatial association between 18F-FMISO and 124I-FIAU on a pixel-by-pixel basis was performed.ResultsCorrelation coefficients between 124I-FIAU uptake and pimonidazole staining intensity were: 0.11 in R3327-AT tumors, ?0.66 in R3327-AT/PC and 0.76 in R3327-AT/HRE, confirming that only in the R3327-AT/HRE tumor was HSV1-tkeGFP gene expression associated with hypoxia.Correlation coefficients between 18F-FMISO and 124I-FIAU uptakes in R3327-AT/HRE tumors were r=0.56, demonstrating good spatial correspondence between the two tracers.ConclusionsWe have confirmed hypoxia-specific expression of the HSV1-tkeGFP fusion gene in the R3327-AT/HRE tumor model and demonstrated the utility of this model for the evaluation of radiolabeled hypoxia tracers.  相似文献   
78.
Chronic cystitis was diagnosed in 36% of children with neuromuscular ureteral dysplasia, in 69% of those with vesicoureteral reflux, in 42% of girls with urolithiasis. Recurrent inflammation was registered in 96, 11% of patients with fibrinous cystitis and catarrhal cystitis, respectively, and in 62% of girls with bullous cystitis. Histological examination of 130 biopsies of bladder mucosa from girls with frequent recurrences of chronic cystitis provided a clear morphological picture of each endoscopic cystitis form. In bullous cystitis there are 2 congenital variants of mucosal structure: overdevelopment of lymphoid tissue as massive lymphoid follicules and lymphangioectatic form. Catarrhal cystitis is characterized by vascular angiomatosis. All the patients with fibrinous cystitis had squamous cell epithelial metaplasia. Morphological findings evidence that fibrinous cystitis is the most severe and unfavorable form of cystitis, bullous cystitis is less severe while catarrhal cystitis is favorable.  相似文献   
79.
Xing L  Li JG  Pugachev A  Le QT  Boyer AL 《Medical physics》1999,26(11):2348-2358
Treatment optimization is usually formulated as an inverse problem, which starts with a prescribed dose distribution and obtains an optimized solution under the guidance of an objective function. The solution is a compromise between the conflicting requirements of the target and sensitive structures. In this paper, the treatment plan optimization is formulated as an estimation problem of a discrete and possibly nonconvex system. The concept of preference function is introduced. Instead of prescribing a dose to a structure (or a set of voxels), the approach prioritizes the doses with different preference levels and reduces the problem into selecting a solution with a suitable estimator. The preference function provides a foundation for statistical analysis of the system and allows us to apply various techniques developed in statistical analysis to plan optimization. It is shown that an optimization based on a quadratic objective function is a special case of the formalism. A general two-step method for using a computer to determine the values of the model parameters is proposed. The approach provides an efficient way to include prior knowledge into the optimization process. The method is illustrated using a simplified two-pixel system as well as two clinical cases. The generality of the approach, coupled with promising demonstrations, indicates that the method has broad implications for radiotherapy treatment plan optimization.  相似文献   
80.
Dysfunction of the solitary kidney was established in 58 patients after the contralateral kidney removal in childhood. The tests were made at senior school age, at adolescence, at adult age. The disorders in the renal function were more severe in pathological processes in the solitary kidney: chronic pyelonephritis, nephron dysplasia, etc. In 49 children the kidney was preserved even in functional failure 70-90%. These patients had less evident renal failure. Basing on this evidence and other arguments, the authors recommend to limit indications for nephrectomy in children.  相似文献   
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