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21.
We report a 62-year-old woman with a primary adenocarcinoma of the appendix mimicking ovarian tumor. We had diagnosed it definitively by laparoscopic appendectomy, and additional surgery was required in this case. However, the present case suggests that, in some cases, if cancer of the appendix can be diagnosed early, laparotomy can be avoided and the cancer treated with minimally invasive laparoscopic surgery alone.  相似文献   
22.
Background: Pressure control ventilation (PCV), high-frequency oscillation (HFO), and intratracheal pulmonary ventilation (ITPV) may all be used to provide lung protective ventilation in acute respiratory distress syndrome, but the specific approach that is optimal remains controversial.

Methods: Saline lavage was used to produce acute respiratory distress syndrome in 21 sheep randomly assigned to receive PCV, HFO, or ITPV as follows: positive end-expiratory pressure (PCV and ITPV) and mean airway pressure (HFO) were set in a pressure-decreasing manner after lung recruitment that achieved a ratio of Pao2/Fio2 > 400 mmHg. Respiratory rates were 30 breaths/min, 120 breaths/min, and 8 Hz, respectively, for PCV, ITPV, and HFO. Eucapnia was targeted with peak carinal pressure of no more than 35 cm H2O. Animals were then ventilated for 4 h.

Results: There were no differences among groups in gas exchange, lung mechanics, or hemodynamics. Tidal volume (PCV, 8.9 +/- 2.1 ml/kg; ITPV, 2.7 +/- 0.8 ml/kg; HFO, approximately 2.0 ml/kg) and peak carinal pressure (PCV, 30.6 +/- 2.6 cm H2O; ITPV, 22.3 +/- 4.8 cm H2O; HFO, approximately 24.3 cm H2O) were higher in PCV. Pilot histologic data showed greater interstitial hemorrhage and alveolar septal expansion in PCV than in HFO or ITPV.  相似文献   

23.
Conformational movement of the C-terminal alpha7 helix in the integrin inserted (I) domain, a major ligand-binding domain that adopts an alpha/beta Rossmann fold, has been proposed to allosterically regulate ligand-binding activity. Disulfide bonds were engineered here to reversibly lock the position of the alpha7 helix in one of two alternative conformations seen in crystal structures, termed open and closed. Our results show that pairs of residues with Cbeta atoms farther apart than optimal for disulfide bond stereochemistry can be successfully replaced by cysteine, suggesting that backbone movement accommodates disulfide formation. We also find more success with substituting partially exposed than buried residues. Disulfides stabilizing the open conformation resulted in constitutively active alphaMbeta2 heterodimers and isolated alphaM inserted domains, which were reverted to an inactive form by dithiothreitol reduction. By contrast, a disulfide stabilizing the closed conformation resulted in inactive alphaMbeta2 that was resistant to activation but became activatable after dithiothreitol treatment.  相似文献   
24.
A 4-year-old boy with Down syndrome (DS) was diagnosed as having acute monoblastic leukemia (AML-M5a). Leukemic cells were CD33+, CD56+ and CD4+, with t(9;11) on cytogenetic analysis and MLL gene rearrangement. After 2 courses of induction therapy using an AML 99-Down protocol failed to obtain complete remission, the patient received cord blood transplantation from an HLA-matched donor (CBT) following a conditioning regimen comprising total body irradiation and cyclophosphamide. Only cyclosporin A was used for graft-versus-host disease prophylaxis. Stem cell transplantation may not be indicated for AML patient with DS in first remission, who display a high rate of life-threatening and fatal toxicity on therapy. This patient remained well controlled in complete remission for 4 years, representing a rare case of DS with chemotherapy-resistant AML successfully treated with a CBT.  相似文献   
25.
Background: To evaluate the effects of home‐based combined resistance training and walking on metabolic profiles in elderly Japanese subjects. Methods: Two hundred and forty‐four elderly Japanese participants were divided into two groups (184 training group and 60 controls). Each exercise training session consisted of one set of 10 repetitions of 11 different resistance exercises, and the training lasted 12 weeks. Fasting blood samples were obtained for measurements of serum levels of total cholesterol, high‐density lipoprotein cholesterol (HDL‐C), triglycerides, hemoglobin A1c, insulin and plasma glucose, before and after the training period. We estimated insulin resistance using the homeostasis model assessment. Five subjects further underwent a two‐step hyperinsulinemic‐euglycemic clamp to evaluate insulin action directly before and after the training. Results: Training resulted in a significant increase in HDL‐C (60 ± 1–62 ± 1 mg/dL, mean ± SE, P < 0.01) and a significant decrease in triglycerides (115 ± 5–106 ± 4 mg/dL, P < 0.05), while no significant changes were observed for total cholesterol, plasma glucose, insulin, homeostasis model assessment or hemoglobin A1c. Glucose infusion rates during the hyperinsulinemic‐euglycemic clamp increased by 30% (P < 0.05) at the 40 mU/m2 per min infusion rate, from 5.4 ± 0.9 to 7.0 ± 1.1 mg/kg per min and by 15% (P < 0.01) at the 400 mU/m2 per min infusion rate, from 9.4 ± 1.0 to 10.8 ± 1.2 mg/kg per min. In the control group, no significant changes were noted except for a significant decrease in HDL‐C. Conclusions: Our home‐based exercise program for elderly is safe and effective for improving metabolic profiles.  相似文献   
26.
OBJECTIVES—To determine changes in demographic variables and severity of rheumatoid arthritis (RA) that may have occurred during the 30 year period from 1960 to 1990 in Japan.
METHODS—Using records of patients diagnosed with RA from two hospitals, demographic and clinical features at initial visit were compared between two groups, one from 1960 to 1965 (group I) and the other from 1985 to 1990 (group II).
RESULTS—Mean age at the time of onset of the disease increased significantly from 37.5 years in group I to 46.9 in group II. The peak age at onset of RA shifted from the third to the fifth decade between group I and group II. There was no obvious change in morbidity as determined by seropositivity, rheumatoid nodules, and assessments of hip involvement.
CONCLUSION—The age at onset of RA was delayed during a recent 30 year period in Japan. This increase in age at onset might result from environmental changes that occurred in Japan or may reflect a birth cohort phenomenon. Improvement of severity of disease was not found in this study.

  相似文献   
27.
Background: The most appropriate method of determining positive end-expiratory pressure (PEEP) level during a lung protective ventilatory strategy has not been established.

Methods: In a lavage-injured sheep acute respiratory distress syndrome model, the authors compared the effects of three approaches to determining PEEP level after a recruitment maneuver: (1) 2 cm H2O above the lower inflection point on the inflation pressure-volume curve, (2) at the point of maximum curvature on the deflation pressure-volume curve, and (3) at the PEEP level that maintained target arterial oxygen partial pressure at a fraction of inspired oxygen of 0.5.

Results: Positive end-expiratory pressure set 2 cm H2O above the lower inflection point resulted in the least injury over the course of the study. PEEP based on adequate arterial oxygen partial pressure/fraction of inspired oxygen ratios had to be increased over time and resulted in higher mRNA levels for interleukin-8 and interleukin-1[beta] and greater tissue inflammation when compared with the other approaches. PEEP at the point of maximum curvature could not maintain eucapneia even at an increased ventilatory rate.  相似文献   

28.
29.
At the Radiation Effects Research Foundation, medical examinations have been conducted biennially since 1958 on a fixed population of approximately 20,000 individuals. Blood pressure measurements and electrocardiographic (ECG) recordings are available for 6,569 individuals who were monitored for at least 11 of the 13 2 year intervals between 1958 and 1984. Data from 601 individuals who had satisfied the Foundation's ECG diagnostic criteria of left ventricular hypertrophy ("Kagan-Yano code") on at least one occasion were reviewed. Both the development and the regression of ECG left ventricular hypertrophy were ascertained in 61 subjects (17 men and 44 women). During the course of development of ECG left ventricular hypertrophy, hypertension (including borderline cases) was noted in 83.3% of the subjects. The most common pattern of ECG left ventricular hypertrophy development was high voltage, followed by ST-T changes. In about half of these cases, the condition of hypertrophy regression was associated with lowering of blood pressure, marked by the disappearance of high voltage ECG readings.  相似文献   
30.
A patient with malignant lymphoma developed goiter and thyrotoxicosis during the course of her disease. A thyroid biopsy revealed involvement of the thyroid gland with a malignant lymphoma. This was associated with the high levels of circulating thyroglobulin and thyroid hormones. The patient was treated with propylthiouracil, local radiotherapy, and nitrogen mustard and prednisone. The patient became euthyroid with the disappearance of goiter. Circulating levels of thyroglobulin and thyroid hormones returned to the normal range.  相似文献   
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