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31.
32.
Tarella  C; Ruscetti  FW; Poiesz  BJ; Woods  A; Gallo  RC 《Blood》1982,59(6):1330-1336
Some laboratory results and clinical situations suggest that human T cells may be important in the regulation of growth of hematopoietic cells. Since the discovery of T-cell growth factor (TCGF), systems are now available for the long-term specific in vitro propagation of mature normal or neoplastic human T cells, providing an opportunity to study the influence of T cells on hematopoiesis. Recently, 24 cell lines from patients with cutaneous T-cell lymphoma (CTCL) and T-cell acute lymphoblastic leukemia (T-ALL) were grown with TCGF and then assessed for release of humoral factors that affect hematopoiesis. Conditioned media (CM) from these cell lines were tested for erythroid burst- promoting activity (BPA) and granulocyte colony-stimulating activity (CSA). BPA was detected in CM from 3/6 cultures of T-ALL patients and 4/6 CTCL cultures. CSA was found in the CM from 6/8 cultures of T-ALL patients, 7/12 CTCL cultures, and 3/4 CTCL cell lines that become independent of exogenous TCGF for growth. The CSA from several of the neoplastic T-cell cultures stimulated high levels of eosinophil colonies, a possible source of the eosinophilia seen in these patients. The ability of continuously proliferating human T lymphocytes, which retain functional specificity and responsiveness to normal humoral regulation, to produce factors that directly or indirectly stimulate myeloid and erythroid colony formation lends further credence to the role of T lymphocytes in regulating hematopoiesis.  相似文献   
33.
Objective: To determine the association between mode of delivery and maternal complications in patients with severe preeclampsia.

Methods: A prospective cohort study was conducted with 500 pregnant women with severe preeclampsia. The mode of delivery, vaginal or caesarean section, was considered the exposure, while the postpartum maternal complications and severe maternal morbidity were the outcomes. Logistic regression analysis was performed to determine the adjusted risk and 95% confidence intervals (95% CI) of maternal morbidity.

Results: Labour was spontaneous in 22.0% and induced in 28.2%, while 49.8% had an elective caesarean section. Ninety-five (67.4%) of the patients in whom labour was induced delivered vaginally. Total Caesarean rate was 68.2%. The risk of severe maternal morbidity was significantly greater in patients submitted to Caesarean section (54.0% versus 32.7%) irrespective of the presence of labour. Factors that remained associated with severe maternal morbidity following multivariate analysis were a diagnosis of HELLP syndrome after delivery (OR?=?3.73; 95% CI: 1.55–9.88) and having a caesarean (OR?=?1.91; 95% CI: 1.52–4.57).

Conclusions: Caesareans are often performed in patients with severe preeclampsia and are associated with significant postpartum maternal morbidity. Induction of labour should be considered a feasible option in these patients.  相似文献   

34.
Seventy-five patients with resistant acute leukemia or lymphoma received high-dose cyclophosphamide and etoposide to explore the activity of this combination in resistant hematologic malignancies, and to determine the maximum doses of these drugs that can be combined without bone marrow transplantation. Etoposide was administered over 29 to 69 hours by continuous infusion corresponding to total doses of 1.8 g/m2 to 4.8 g/m2. Cyclophosphamide, 50 mg/kg/d, was administered on 3 or 4 consecutive days total 150 to 200 mg/kg ideal body weight). At all dose levels myelosuppression was severe but reversible. Mucosal toxicity was dose-limiting with the maximum tolerated dose level combining etoposide 4.2 g/m2 with cyclophosphamide 200 mg/kg. Continuous etoposide infusion produced stable plasma levels that were lower than would be achieved after administration by short intravenous infusion, and this could explain our ability to escalate etoposide above the previously reported maximum tolerated dose. There were 28 complete (35%) and 12 partial (16%) responses. Median duration of complete response (CR) was 3.5 months (range 1.1 to 20+). Seventeen of 40 patients (42%) with acute myelogenous leukemia (AML) achieved CR, including 6 of 20 (30%) with high-dose cytosine arabinoside resistance. We conclude that bone marrow transplantation is not required after maximum tolerated doses of etoposide and cyclophosphamide. This regimen is active in resistant hematologic neoplasms, and the occurrence of CR in patients with high-dose cytosine arabinoside-resistant AML indicates a lack of complete cross-resistance between these regimens.  相似文献   
35.

OBJECTIVE:

to analyse the Redness, Oedema, Ecchymosis, Discharge, Approximation (REEDA) scale reliability when evaluating perineal healing after a normal delivery with a right mediolateral episiotomy.

METHOD:

observational study based on data from a clinical trial conducted with 54 randomly selected women, who had their perineal healing assessed at four time points, from 6 hours to 10 days after delivery, by nurses trained in the use of this scale. The kappa coefficient was used in the reliability analysis of the REEDA scale.

RESULTS:

the results indicate good agreement in the evaluation of the discharge item (0.75< Kappa ≥0.88), marginal and good agreement in the first three assessments of oedema (0.16< Kappa ≥0.46), marginal agreement in the evaluation of ecchymosis (0.25< Kappa ≥0.42) and good agreement regarding redness (0.46< Kappa ≥0.66). For the item coaptation, the agreement decreased from excellent in the first assessment to good in the last assessment. In the fourth evaluation, the assessment of all items displayed excellent or good agreement among the evaluators.

CONCLUSION:

the difference in the scores among the evaluators when applying the scale indicates that this tool must be improved to allow an accurate assessment of the episiotomy healing process.  相似文献   
36.

Objective

The objective of this study was to assess changes in upper trapezius myoelectric activity and pain in patients with nonspecific neck pain after a single session of acupuncture (ACP).

Methods

A blinded randomized clinical trial was conducted. Fifteen patients with nonspecific neck pain and 15 healthy participants were enrolled in a randomized, single-blinded, crossover study. Each participant was subjected to a single session of ACP and sham acupuncture (SACP). The electromyography (EMG) signal of the upper trapezius muscle was recorded during different step contractions of shoulder elevation force (15%-30% maximal voluntary contraction) before and after ACP treatment.

Results

Significant effects were confirmed after the treatment (ACP and SACP) for Numeric Rating Scale scores (F1,28 = 51.61; P < .0001) and pain area (F1,2 = 32.03; P < .0001). Significant decreases in the EMG amplitude were identified for the nonspecific neck pain group (NPG) (F1,112 = 26.82; P < .0001) and the healthy participant group (HPG) (F1,112 = 21.69; P < .0001) after ACP treatment. No differences were identified between the ACP and SACP treatment protocols for Numeric Rating Scale score (NPG: F1,28 = 0.95; P = .33), pain area (NPG: F1,28 = 1.97; P = .17), or EMG amplitude (NPG: F1,112 = 0.47; P = .49; HPG: F1,112 = 0.75; P = .38).

Conclusion

The effect of ACP at acupoints triple energizer 5 and large intestine 11 triple energizer 5, or in close proximity, contributes to pain relief among patients with nonspecific neck pain. The electromyographic analysis indicated a greater resistance to muscle fatigue and decrease of activity of the upper trapezius muscle among healthy participants and patients with nonspecific neck pain.  相似文献   
37.
Background: The unsupported upper-limb exercise (UULEX) and 6-min peg board ring tests (6PBRTs) have been developed to measure peak unsupported arm exercise capacity and arm endurance, respectively, in individuals with chronic obstructive pulmonary disease. These tests are valid and reproducible in this population; however, the reproducibility of healthy adults is currently unknown. Objective: To determine the within-day test–retest reliability of the UULEX and 6PBRT in healthy adults. Method: The study included 41 healthy adults, aged 38.3 ± 17.9 years old, who performed both tests, twice each on the same day, with a 30-min rest in between. Before and immediately after the tests, blood pressure (BP), heart rate (HR), perception of exertion, and arm fatigue were measured. Time to perform the test and number of rings moved were recorded for the UULEX and 6PBRT, respectively. Results: The UULEX was reproducible on Bland–Altman analysis with lower and upper limits of agreement: 2.40 and ?2.49 min, respectively (bias = ?0.05; p = 0.817) and intraclass correlation coefficient (ICC) = 0.85 (p < 0.0001) for time in minutes for the first and second tests. The 6PBRT was not reproducible on Bland–Altman analysis with lower and upper limits of agreement of 31.64 and ?114.54 (bias = ?41.45; p < 0.0001) and ICC = 0.91 (p < 0.0001) for the number of rings moved. Conclusion: UULEX is a reliable test in healthy adults. Only one test is adequate when measuring peak unsupported arm exercise capacity using the UULEX in healthy adults, while more than two tests may be needed to measure arm endurance using the 6PBRT.  相似文献   
38.
39.
Bowen  BJ; Morgan  EH 《Blood》1987,70(1):38-44
The mechanisms underlying the impaired utilization of transferrin-bound iron by erythroid cells in the anemia of the Belgrade laboratory rat were investigated using reticulocytes from homozygous anemic animals and transferrin labeled with 59Fe and 125I. The results were compared with those obtained using reticulocytes from phenylhydrazine-treated rats and iron-deficient rats. Each step in the iron uptake mechanism was investigated, ie, transferrin-receptor interaction, transferrin endocytosis, iron release from transferrin, and transferrin exocytosis. Although there were quantitative differences, no fundamental difference was found in any of the abovementioned aspects of cellular function when the reticulocytes from Belgrade rats were compared with those from iron-deficient animals. The basic defect in the Belgrade reticulocytes must therefore reside in subsequent steps in iron uptake, after it is released from transferrin within endocytotic vesicles, ie, in the mechanism by which it is transferred across the lining membrane of the vesicles into the cell cytosol. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of reticulocyte ghosts extracts demonstrated a prominent protein band of mol wt 69,000 that was absent or present only in low concentration extracts from the other two types of reticulocytes. This may be a result of the genetic defect.  相似文献   
40.
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