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1.
Annals of Hematology - This study assessed treatment patterns and healthcare resource utilization (HRU) of patients with severe aplastic anemia (SAA) with insufficient response to immunosuppressive...  相似文献   
2.
Recently, the role and timing of surgery for treating secondary and tertiary hyperparathyroidism (HPT) have been questioned. In order to delineate the indications for surgery in these patients, a retrospective analysis of 53 consecutive patients treated with parathyroidectomy was conducted. Subtotal thyroidectomy was done in 37 of 45 patients undergoing their initial operations for HPT. Eight additional patients were referred after failed operations. Of 33 patients with preoperative bone pain, 70% improved. Joint pain improved in 87% of 30 patients, pruritus improved in 81% of 27 patients, and preoperative malaise improved in 73% of 33 patients after parathyroidectomy. Abdominal pain and irritated eyes were unlikely to improve. The best predictors of a successful outcome were a markedly elevated preoperative immunoreactive parathyroid hormone (mid-region) level and an elevated alkaline phosphatase level. There were no perioperative deaths. One patient (1.6%) had a recurrent laryngeal nerve injury, and one patient required reoperation for a neck hematoma. No patient had permanent hypoparathyroidism, but transient hypocalcemia (less than 7 mg/dL) occurred in 22%. Postoperative hypocalcemia correlated with elevated preoperative alkaline phosphatase levels (r2 = 0.247).  相似文献   
3.
The efficacy and limitations of percutaneous endoscopic gastrostomy.   总被引:2,自引:0,他引:2  
We analyzed 64 percutaneous endoscopic gastrostomy procedures performed by us between 1986 and 1990. Thirty patients had neurologic disease; 16 had head and neck cancers; eight had other malignancies; two had acquired immunodeficiency syndrome; and eight had other problems. Seven patients died within 30 days of complications (n = 4) or the primary illness (n = 3). Mean follow-up was 6 months; an additional patient died of aspiration and eight others died of their underlying illness. There were 19 complications (32%). Four wound complications occurred. Nine patients developed aspiration pneumonia within 3 days of the procedure, four of whom died in the hospital. Of the 24 patients with a history of aspiration, nine experienced aspiration during or after percutaneous endoscopic gastrostomy. Patients with a history of aspiration were more likely to have perioperative aspiration pneumonia, and patients who experienced aspiration were more likely to die.  相似文献   
4.
Thyroid stimulating hormone (TSH) and epidermal growth factor (EGF) are growth factors for some thyroid cells in cultures. We have previously found more EGF receptors in neoplastic human thyroid tissues than in normal thyroid tissues. We have also found a higher TSH-stimulated adenylate cyclase (AC) activity in neoplastic human thyroid tissues than in normal thyroid tissues. To clarify the relationship between the effect of EGF and TSH on thyroid tissue, we measured the binding of EGF and TSH and the basal, TSH-stimulated and forskolin-stimulated adenylate cyclase activity in 49 normal, hyperplastic and neoplastic human thyroid tissues (5 normal, 2 Hashimoto thyroiditis, 5 Graves' disease, 14 multinodular goiters, 9 follicular adenomas, S follicular carcinomas, 8 papillary carcinomas, and 1 undifferentiated carcinoma). Specific binding of EGF and TSH were measured by radioreceptor assays using competitive inhibition of radio-labeled ligand by unlabeled ligand. Basal, maximally (300 mU/ml) TSH-stimulated, and maximally (100 mM) forskolin-stimulated adenylate cyclase activities were also measured in the same membrane particulate fractions from the thyroid tissues. We found: neoplastic thyroid tissues bind more labeled EGF than nonneoplastic thyroid tissues; follicular adenomas and carcinomas have higher EGF binding than other thyroid tissues; a weak but significant correlation between specific EGF binding and specific TSH binding, and between specific EGF binding and TSH-stimulated adenylate cyclase activity of the thyroid membrane preparations. These findings are consistent with the hypothesis that TSH stimulates an increase in thyroid EGF receptors by increasing intracellular cAMP. The higher binding of EGF and the higher TSH-stimulated AC activity may explain why thyroid neoplasms grow to a larger size than normal thyroid tissues.
Resumen La hormona estimuladora de tiroides (TSH) y el factor de crecimiento epidermal (EGF) son factores de crecimiento para algunas células tiroideas en cultivo tisular. Previamente hemos informado el hallazgo de más receptores de EGF en tejidos tiroideos neoplásicos humanos que en tejidos tiroideos normales. Con el objeto de clarificar la relación entre el efecto del EGF y de la TSH sobre el tejido tiroideo, realizamos la determinacion de la ligación del EGF y de la TSH y de la actividad basai y de la actividad estimulada por TSH y forskolina de la adenilato-ciclasa (AC) en 49 especímenes de tejido tiroideo humano (5 normales, 2 tiroiditis de Hashimoto, 5 enfermedad de Graves, 14 bocios multinodulares, 9 adenomas foliculares, 5 carcinomas foliculares, 8 carcinomas papilares, y 1 carcinoma indiferenciado). La ligadura especifica del EGF y de la TSH fue medida mediante determinaciones de receptores utilizando inhibición competitiva radiomarcada. También se determinó la actividad basai y la actividad estimulada por forskolina de la adenilato-ciclasa en las mismas fracciones de tejidos tiroideos. Se registraron los siguientes hallazgos: los tejidos neoplásicos ligan más EGF marcado que los tejidos tiroideos no neoplásicos; los adenomas foliculares y los carcinomas poseen una capacidad de ligación del EGF mayor que los otros tejidos tiroideos; hay una débil pero significativa correlación entre la ligación especifíca del TGF y la de la TSH, y entre la ligación específica del EGF y la actividad estimulada por TSH de la adenilato-ciclasa en las preparaciones de membrana tiroidea. Estos hallazgos aparecen consistentes con la hipótesis de que la TSH estimula un aumento en los receptores de EGF mediante el incremento de la cAMP intracelular. La aumentada ligación de EGF y la incrementada actividad estimulada de TSH pueden explicar el por qué los neoplasmas tiroideos crecen hasta un tamaño mayor que los tejidos tiroideos normales.

Résumé La thyroid stimulating hormone (TSH) et l'epidermal growth factor (EGF) sont des facteurs de croissance agissant sur certaines cellules thyroïdes en culture. Nous avons trouvé qu'il y avait plus de récepteurs EGF dans le tissu thyroïde humain néoplasique que dans le tissu thyroïdien normal. Nous avons également montré qu'il y avait plus d'activité d'adenylate cyclase stimulée par la TSH dans le tissu thyroïden néoplasique par rapport au tissu normal. Pour clarifier le rapport entre les effets de l'E.GF et la TSH sur le tissu thyroïden, nous avons mesuré l'activité de liaison d'EGF, de TSH et l'activité adénulate cyclase de base, stimulée par la TSH, et par la forskoline chez 49 patients ayant du tissu normal, hyperplasique ou néoplasique (5 normaux, 2 thyroïdites de Hashimoto, 5 maladies de Basedow, 14 goîtres multinodulaires, 9 adénomes folliculaires, 5 cancers folliculaires, 8 cancers papillaires, et 1 cancer indifférencié). Les liaisons spécifiques d'EGF et de TSH ont été mesurées par le dosage des récepteurs nucléaires par la méthode de déplacement des ligands marqués par des ligands froids (non marquées). Les activités adénylate cyclase de base, maximale (300 mU/mL), stimulée par la TSH (300 mU/mL) et la forskoline (100 mM) ont été également mesurées dans les mêmes fractions de particules membranaires provenant des tissus thyroïdens. Nous avons trouvé que: les tissus néoplasiques se liaient davantage avec l'EGF que les tissus non néoplasiques; les adénomes folliculaires et les cancers avaient un index de liaison plus élevé que les autres tissus thyroïdens; et il y avait une corrélation faible mais significative entre la liaison spécifique EGF et TSH, et entre la liaison spécifique EGF et l'activité adénylate cyclase des préparations de membrane thyroïdienne. Ces résultats sont en faveur de l'hypothèse selon laquelle la TSH provoque une augmentation des récepteurs EGH de la thyroïde en augmentant la concentration intracellulaire d'AMP cyclique. Le degré de liaison d'EGF élevé, et l'augmentation de l'activité stimulée par la TSH peuvent expliquer la croissance accélérée des tissus néoplasiques par rapport à celle des tissus normaux.


Presented at the International Association of Endocrine Surgeons in Toronto, Ontario, Canada, September, 1989.

Supported in part by the Medical Research Service of the Veterans Administration Medical Center, San Francisco, California and the Affirmative Action Faculty Development Grant of the University of California, San Francisco, California.  相似文献   
5.
This case report describes a dog suffering from a co‐infection with Babesia and Anaplasma parasites. Anaplasma platys was found to be responsible for the anaplasmosis by molecular biology techniques, while microscopical and serological evidence was found for a coexistent babesiosis, although this could not be confirmed by polymerase chain reaction. Moreover, the possible risk of import of exotic pathogens is highlighted.  相似文献   
6.
The present study compared the recently developed multilocus sequence typing (MLST) approach with a well-established molecular typing technique, pulsed-field gel electrophoresis (PFGE), for subspecies differentiation of Enterococcus faecalis isolates. We sequenced intragenic regions of three E. faecalis antigen-encoding genes (ace, encoding a collagen and laminin adhesin; efaA, encoding an endocarditis antigen; and salA, encoding a cell wall associated antigen) and one housekeeping gene (pyrC) of 22 E. faecalis isolates chosen largely for their temporal and geographical diversity, but also including some outbreak isolates. MLST analysis of polymorphic regions of these four genes identified 13 distinct sequence types (STs) with different allelic profiles; the composite sequences generated from the four sequenced gene fragments of individual isolates showed 98.3 to 100% identity among the 22 isolates. We also found that the allelic profiles from two sequences, ace and salA, were sufficient to distinguish all 13 STs of this study. The 13 STs corresponded to 12 different PFGE types, with one previously designated PFGE clone (a widespread U.S. clone of beta-lactamase-producing isolates) being classified into two highly related STs which differed at 2 of 2,894 bases, both in the same allele. MLST also confirmed the clonal relationships among the isolates of two other PFGE clonal groups, including vancomycin resistant isolates. Thus, this pilot study with representative E. faecalis isolates suggests that, similar to PFGE, the sequence-based typing method may be useful for differentiating isolates of E. faecalis to the subspecies level in addition to identifying outbreak isolates.  相似文献   
7.
Our previous work reported that most Enterococcus faecalis strains adhered to the extracellular matrix proteins collagen types I and IV and laminin after growth at 46 degrees C, but not 37 degrees C, and we subsequently identified an E. faecalis sequence, ace, that encodes a bacterial adhesin similar to the collagen binding protein Cna of Staphylococcus aureus. In this study, we examined the diversity of E. faecalis-specific ace gene sequences among different isolates obtained from various geographic regions as well as from various clinical sources. A comparison of nucleotide and deduced amino acid sequences of Ace from nine E. faecalis strains identified a highly conserved N-terminal A domain, followed by a variable B domain which contains two to five repeats of 47 amino acids in tandem array, preceded by a 20-amino-acid partial repeat. Using 17 other strains collected worldwide, the 5' region of ace that encodes the A domain was sequenced, and these sequences showed > or =97.5% identity. Among the previously reported five amino acids critical for collagen binding by Cna of S. aureus, four were found to be identical in Ace from all strains tested. Polyclonal immune rabbit serum prepared against recombinant Ace A derived from E. faecalis strain OG1RF detected Ace in mutanolysin extracts of seven of nine E. faecalis strains after growth at 46 degrees C; Ace was detected in four different molecular sizes that correspond to the variation in the B repeat region. To determine if there was any evidence to indicate that Ace might be produced under physiological conditions, we quantitatively assayed sera collected from patients with enterococcal infections for the presence of anti-Ace A antibodies. Ninety percent of sera (19 of 21) from patients with E. faecalis endocarditis showed reactivity with titers from 1:32 to >1:1,024; the only 2 sera which lacked antibodies to Ace A had considerably lower titers of antibodies to other E. faecalis antigens as well. Human-derived, anti-Ace A immunoglobulins G purified from an E. faecalis endocarditis patient serum inhibited adherence of 46 degrees C-grown E. faecalis OG1RF to collagen types I and IV and laminin. In conclusion, these results show that ace is highly conserved among isolates of E. faecalis, with at least four variants related to the differences in the B domain, is expressed by different strains during infection in humans, and human-derived antibodies can block adherence to these extracellular matrix proteins.  相似文献   
8.
The aggressiveness of follicular thyroid cancer (FTC) varies widely, and metastasis is the primary cause of death. Uncontrolled proliferation of cancer cells may be associated with loss of growth factor control. We investigated the effects of stimulating (epidermal growth factor [EGF]; thyreotropin [TSH] in low concentrations) and inhibiting growth factors (transforming growth factor beta 1 [TGF beta 1]; TSH in high concentrations) on invasion and growth of FTC cell lines from the thyroid tumor (FTC133) and from the lymph node (FTC236) and lung (FTC238) metastases of the same patient. Invasion—penetration through an 8m pore membrane, covered by Matrigel (basement membrane)—and growth were measured using the MTT-method. EGF (10 ng/ml) and TSH in low concentrations (1 mU/ml) stimulated invasion and growth of all FTC cell lines, but the amplitude of stimulation differed significantly. The parental cell line FTC133 was considerably more responsive to growth factor stimulation than the metastatic clones. Invasion of FTC133 was enhanced by 42% (EGF;p<0.02) and 21% (TSH;p<0.01), invasion of FTC236 by 8% (EGF;p<0.02) and 8% (TSH;p<0.01), and invasion of FTC238 by 9% (EGF;p<0.02) and 8% (TSH;p<0.01). Conversely, invasion and growth of FTC133 were significantly more inhibited by TGF beta 1 (10 ng/ml) and supraphysiologic concentrations of TSH (100 mU/ml) than the cell lines from the lymph node and lung metastases. At day 7, invasion of FTC133 was inhibited by 32% (TGF beta 1;p<0.02) and 21% (TSH;p<0.01), invasion of FTC236 by 18% (TGF beta 1;p<0.02) and 11% (TSH;p<0.01), and invasion of FTC238 by 16% (TGF beta 1;p<0.02) and 12% (TSH;p<0.01). Moreover, we analyzed growth factor independence in minimally supplemented or unsupplemented medium. Growth, but no invasion was evident when cells were cultured completely unsupplemented over 7 days. These results suggest that metastatic FTCs may have developed by escaping from the normal control of TSH and other growth factors.  相似文献   
9.
10.
There is a general consensus that total or near-total thyroidectomy is the optimal treatment for patients with high risk differentiated thyroid cancer (DTC), but the optimal extent of thyroidectomy in patients with low risk DTC continues to be controversial. To determine the optimal extent of thyroidectomy in patients with low risk DTC, we used decision analysis to compare the trade-offs of total thyroidectomy (TT) to thyroid lobectomy (TL). The decision analysis model included the probabilities of thyroidectomy complications, risk of DTC recurrence, and death from DTC. This information was obtained from the literature and from outcome data for patients with low risk DTC from our institution. In addition, the concept of utilities was used in the analysis. To determine the utility of each health outcome state (thyroidectomy complication, DTC recurrence, and DTC mortality for low risk patients) a survey was conducted. Overall, prospective patients viewed DTC recurrence as less desirable than thyroidectomy complication. The utilities assigned by the survey participants varied over a wide range, with 61.5% of the individuals viewing the occurrence of a thyroidectomy complication as better than DTC recurrence. At baseline utilities and probabilities, TT had a higher expected utility than TL. One-way sensitivity analysis varying the rates of (1) thyroidectomy complication, (2) DTC recurrence, and (3) DTC mortality over the possible range showed that complication from initial thyroidectomy was the most important factor that determined the preferred extent of thyroidectomy. TL was the preferred surgical approach only if a complication rate of > 33:1, TT/TL complication rate ratio, was assumed. When no differences in DTC recurrence between the two approaches was assumed in the model, TL had a higher expected utility using the baseline utilities of thyroidectomy complication and DTC mortality. The analysis indicates that TT in patients with low risk DTC is preferable to TL. However, TL is preferred if (1) no difference in the DTC recurrence rate between the two approaches is assumed, (2) a higher complication rate for TT is used (> 33 times higher), or (3) the utility ratio of thyroidectomy complication to DTC recurrence is < 0.8 TL. We believe this decision analysis model provides an objective approach that others can use to select the optimal extent of thyroidectomy based on patient preference of health outcome states, institution-specific outcome data for DTC recurrence or mortality, and the surgeon-specific complication rate.  相似文献   
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