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71.
Details of the cellular and biochemical mechanisms involved in focal destruction of bone at sites of tumor osteolysis are unknown. It has been shown that tumors from sarcoma (2472) cell lines induce focal osteolysis in mice by stimulating formation and activation of osteoclasts. In this report, the influence of 2472 tumors on the skeletons of osteoclast-deficient animals (op/op) was studied. After op/op femora had been inoculated with 2472 cells, tumors developed and focal osteolysis occurred. There were more osteoclasts per histologic section in sham-injected femora (19 ± 5) than in tumor-bearing femora (412 ± 129) (p < 0.05). The size of the osteoclasts also increased from 304 ± 81 μm2 in sham-injected limbs to 407 ± 62 μm2 in tumor-bearing limbs (p < 0.001). Conditioned media from 2472 op/op tumor explants contained macrophage colony-stimulating factor. A deficiency of osteoclasts in op/op mice is the result of the absence of this factor; therefore, these data introduce the possibility that macrophage colony-stimulating factor derived from 2472 tumor may be responsible for directing osteoclast-mediated osteolysis at sites of the tumor.  相似文献   
72.
A case of hyperreactio luteinalis in an otherwise normal pregnancy is reported. Ascites was present, but no peritoneal implants or adenopathy were seen. Findings that would have suggested the correct diagnosis are the symmetrical and bilateral pattern of the mass, as well as the rather uniform size of the loculi, which were 1 to 3 cm in diameter.  相似文献   
73.
This study reviews the diagnosis and management of a consecutive series of 33 phyllodes tumours of the breast treated at The Royal Marsden Hospital, Sutton, between 1981 and 1992. The mean age of patients at presentation was 41 years (range 15-67 years). Tumours occurred equally in each breast and were significantly more common in the upper outer quadrant (chi 2 = 12.7, df = 3, P < 0.01). Clinical features (age, tumour size, palpation) and diagnostic investigations (mammography, ultrasound and fine needle aspiration cytology) were not sufficiently accurate to reliably make a preoperative diagnosis or predict histological type (benign, borderline or malignant). The diagnosis of phyllodes should be considered in patients aged 30-50 years with an apparent fibroadenoma. Of the patients, 66% underwent wide excision or mastectomy resulting in a favourable local recurrence rate of 14%. Our experience and review of the literature suggests that adequate local surgery is the treatment of choice and adjuvant treatments have no place in the routine management of phyllodes tumours. Regional lymph nodes were not involved in any of our patients and axillary dissection is not indicated.  相似文献   
74.
Our work concerned 15 patients (9 males, 6 females) with a mean age of 29.5 years, having a hematologic malignant disease and undergoing allogenic bone marrow transplantation.We studied :
1. The metabolic disorders induced by the conditioning regimen (chemotherapy and total body irradiation) pregraft accompanying cytolysis (day −7, −5, −2).
2. The corrective effect of a total parenteral nutrition introduced 2 days before the transplantation and pursued during 30 days post-graft (day −2 to day 30).
3. The interest of a high calorie intake (BEE × 2) and, after randomisation, of a variable nitrogen intake (24% of the total calorie intake for group A [8 patients] and 14% for group B [7 patients]). The patient characteristics of these two groups were closely comparable. Urinary parameters were studied daily (3-methylhistidine, cratinine, nitrogen) and blood parameters weekly (transferrin, pre-albumin, albumin, retinol binding protein).
We observed globally :
-- An excellent result of the nutritional support without significant weight loss;
-- protein catabolism stopped with a recovery of synthesis of RBP after day 7 and pre-albumin from day 7;
-- a decrease in muscle catabolism.
The randomized study showed :
-- a significant difference in nitrogen excretion between group A and group B;
-- earlier and better protein synthesis recovery in group A, particularly with regard to RBP and pre-albumin.
In conclusion, we recommend for the patients undergoing bone marrow transplantation :
-- nutritional support should be introduced before the conditioning regimen;
-- a high calorie intake (BEE × 2) with a nitrogen intake between 14% and 24% of the total calorie intake;
-- cyclic parenteral nutrition should be pursued during the second and third month post-graft.

Résumé

Nous avons étudié chez 15 malades (9 hommes, 6 femmes) d'âge moyen 29,5 ans, présentant une hémopathie maligne et nécessitant une greffe de moelle osseuse allogénique :
1. Les désordres métaboliques induits par la chimiothérapie et l'irradiation corporelle totale en période de prégreffe au cours de la cytolyse (J −7, J −5, J −2).
2. L'effet correcteur d'une nutrition parentérale introduite deux jours avant la greffe et exclusive durant les 30 jours post-greffe (J −2, J + 30).
3. L'intérêt d'un apport calorique élevé (BEE × 2) et, par randomisation, d'un apport azoté variable (24 % de l'apport calorique total pour le groupe A et 14 % pour le groupe B).
Nous avons étudié quotidiennement certains paramètres urinaires (3MeH, créatinine, azote) et les paramètres sanguins (transferrine, préalbumine, albumine, RBP) l'ont été de façon hebdomadaire.Nous avons constaté globalement un excellent résultat du support nutritif sans perte de poids significative, un arrêt du processus catabolique protéique avec reprise de synthèse après J +7 pour la RBP et pour la préalbumine et une réduction du catabolisme musculaire.L'étude randomisée a mis en évidence :
-- une différence statistique dans l'excrétion axotée, plus intense dans le groupe A,
-- une reprise des synthèses protéiques, plus précoce et plus performante dans ce même groupe pour la RBP et la préalbumine.
En conclusion et compte tenu de l'ensemble des éléments, nous préconisons chez ces malades devant subir une greffe de moelle osseuse allogénique :
-- une attitude préventive en ce qui concerne la nutrition à débuter avant le conditionnement,
-- un apport calorique élevé (BEE × 2) et un apport azoté situé entre 14 % et 24 % de l'apport calorique total,
-- une étude prospective quant à l'intérêt de certains acides aminés et d'une nutrition parentérale cyclique poursuivie au 2e et au 3e mois post-greffe.
Mots clés: greffe de moelle osseuse; nutrition parentérale totale; apport azotéKey-words: bone marrow transplantation; total parenteral nutrition; nitrogen intake  相似文献   
75.
For substances eliminated from blood by the liver, the effect of a change in unbound fraction of drug (fu b )on steady state total (C b )and unbound (Cu b )blood concentrations has hitherto only been considered for the two limiting cases, i.e., at the upper and lower extremes of hepatic intrinsic clearance (CL int ).For a substance of very low CL int ,if fu b changes, C t will change and Cu b will remain constant, whereas if CL int isvery high, Cu b will change and C b will remain constant.The present study defines the effects of a change in fu b on C b and Cu b over the whole CL int range. Computer simulations were undertaken which predicted that, for a given change in fu b ,absolute and relative changes in C b would decreasenonlinearly with increasing CL int, twhile the relative change in Cu b would increasewith CL int .The absolute change in Cub would be independent of CL int .Significant changes in Cb and Cu b would be observed at intermediate values of CL int not just at the high and low extremes. These theoretical predictions were investigated experimentally in the isolated perfused rat liver by examining the effects of a change in fu b of sodium taurocholate a substance with intermediate CL int (such that at fu b =0.27,hepatic extraction ratio=0.71) induced by concurrent administration of sodium oleate. Sodium 24- 14 C-taurocholate (specific activity 52 Ci/mmol) was infused into the reservoir in a recycling system at 30 mol/hr for 105 min (n=6). At 45 min a bolus dose of sodium oleate (50 mmol) was administered to the reservoir, followed by a constant infusion of 143 mmol/hr for 1 hr. Following the administration of oleate, taurocholate fu b fell promptly by 55% (0.27–0.12). There was a relative increase of taurocholate C b of 22.7% and a relative decrease in Cu b of 45.4%, in accordance with the simulations (p<0.05). We conclude that important changes in unbound steady-state concentration, the pharmacologically active moiety, can occur upon changes in unbound fraction with compounds of intermediate hepatic intrinsic clearance.This study was supported by the National Health and Medical Research Council of Australia.  相似文献   
76.
Major forces are at work within the health care system that drive the development of clinical standards or guidelines. This process must be tied in a "feedback-loop" system to a more accurate assessment of patient outcomes. There is a major controversy at the foundation of the process that is pitting the opinions from consensus panels of experts against the inability of individual physicians to accurately estimate the outcomes of different options through implicit systems. In many instances, the quality of medical evidence is poor. Many groups within organized medicine are attempting to write guidelines, and at least four major challenges must be confronted before guidelines are widely adopted by clinicians. A new federal agency may provide the necessary resources to focus the debate on guidelines. Guidelines may eventually enhance the quality of medical care.  相似文献   
77.
The author describes a role for psychotherapy in ganyphilia, the homoerotic interest by adult males in adolescents. This paraphilia, which is commonly pandered to by street hustlers, often comes to light when the subject is arrested. When ganyphilia is embedded within a framework of disordered narcissism, the personality disorder itself can be effectively treated by a psychoanalytic psychotherapy informed by contemporary self psychology. After locating ganyphilia in a historical/mythological context, the author presents aspects of the psychotherapy of a court-mandated case to demonstrate both etiologic forces and the treatment process.  相似文献   
78.
Confocal Raman microspectroscopy (CRM) provides an important and novel means of analyzing the chemical composition of the adhesive/dentin (a/d) interface. The purpose of this study was to develop a method for quantitative determination of the degree of adhesive penetration at the a/d interface using CRM. Three commercial dentin adhesive systems [Scotchbond Multipurpose Plus (SBMP+), Single Bond (SB), and Primer Bond NT (PBNT)] based on the total etch and "wet" bonding technique were examined in this study. Human dentin specimens treated with these adhesives were analyzed with CRM mapping across the a/d interface. Also, Raman spectra were collected on model mixtures of adhesive and type I collagen, and the ratios of the relative intensities of the Raman bands corresponding to adhesive and collagen were used for the construction of calibration curves. By comparing the Raman band ratios of interface specimens to the calibration curves, the percent of adhesive as a function of spatial position across the a/d interface was determined. The results show that there is a gradual decrease in penetration as a function of position for all three adhesive systems while the adhesive concentration gradient decreases in the order of SBMP+ > SB > PBNT. These differences in penetration of the three adhesives at the a/d interface also are discussed relative to the composition and phase segregation in adhesives. Additionally, our results indicate that confocal Raman microspectroscopy is a reliable in situ analytical technique for simple and rapid quantitative determination of adhesive penetration at its interface with prepared dentin.  相似文献   
79.
A solid-phase enzyme immunoassay using both mouse monoclonal and goat polyclonal antibodies against carcinoembryonic antigen (CEA) was developed. The assay detects 0.6 to 1.2 ng of CEA per ml of serum and has 3 incubation steps which can be performed in 1 day. Polystyrene balls coated with polyclonal goat anti-CEA antibodies are first incubated with heat-extracted serum samples. Bound CEA is then detected by addition of mouse monoclonal antibodies, followed by goat IgG anti-mouse IgG1 coupled to alkaline phosphatase. Results with this enzyme immunoassay using monoclonal antibodiies (M-EIA) have been compared with those obtained by the conventional inhibition radioimmunoassay (RIA) using goat antiserum. Three hundred and eighty serum samples from 167 patients with malignant or non-malignant diseases and from 134 normal individuals with or without heavy smoking habits were analyzed by the 2 assays. Excellent correlation between the results of the 2 assays was obtained, but the M-EIA, using monoclonal antibodies from a single hybridoma, did not discriminate better than the conventional RIA between CEA produced by different types of carcinoma and between CEA associated with malignant or non-malignant diseases. Follow-up studies of several patients by sequential CEA determinations with the 2 assays showed that the M-EIA was as accurate as the RIA for the detection of tumor recurrences.  相似文献   
80.
Expression of CDX2 and MUC2 in Barrett's mucosa   总被引:3,自引:0,他引:3  
Barrett's mucosa is a risk factor for esophageal adenocarcinoma and should be detected at an early stage. It is defined by the presence of columnar epithelium with goblet cells in the lower esophagus, but histologic diagnosis can be uncertain in the absence of distinct goblet cells. We investigated 55 biopsies from 48 patients with endoscopically plain Barrett's esophagus and performed immunohistochemistry for CDX2 and MUC2. In addition, alcian blue (pH 2,5)/PAS staining was done. In histologically unequivocal Barrett's mucosa, nuclear expression of CDX2 in goblet cells and many columnar cells, as well as cytoplasmic positivity for MUC2 in goblet cells, could be observed. Alcian blue (pH 2,5)/PAS stained acidic mucins in goblet cells and in some non-goblet columnar cells. In six cases, no definite Barrett's mucosa was present, and no expression of MUC2 could be observed. In these biopsies, there was granular cytoplasmic and/or focal nuclear staining for CDX2 in non-goblet columnar epithelial cells, indicating their intestinal differentiation. We suggest that this peculiar mucosa is the precursor of unequivocal Barrett's mucosa and would designate it early Barrett's mucosa. Alcian blue for acidic mucins is inconsistent in this epithelium and does not reliably indicate early intestinal differentiation.  相似文献   
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