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排序方式: 共有193条查询结果,搜索用时 12 毫秒
81.
82.
Andrews  RG; Singer  JW; Bernstein  ID 《Blood》1986,67(3):842-845
A monoclonal antibody, 12-8, prepared against KG-1a cells, recognizes an approximately 115-kd cell surface antigen and reacts with 3% to 4% of bone marrow cells, including most of the blast cells. The antigen is not expressed on peripheral blood cells. Marrow cells expressing 12-8 collected by fluorescence-activated cell sorting contained nearly all of the unipotent (CFU-GM, BFU-E) and multipotent (CFU-MIX) colony- forming cells. The isolated 12-8 positive marrow population also contained precursors of these colony-forming cells. In a two-stage long- term marrow culture system employing irradiated allogeneic marrow adherent cells, 12-8 positive cells produced both unipotent and multipotent colony-forming cells for ten weeks. Moreover, the output of colony forming cells substantially exceeded the input. Antibody 12-8 appears useful for analysis and possibly enrichment of hematopoietic progenitor cells that include colony-forming cell precursors.  相似文献   
83.
Antibody L4F3 is a murine monoclonal antibody that recognizes an antigen expressed on in vitro colony-forming cells, including virtually all CFU-GM, CFU-Meg, BFU-E, and CFU-Mix. In the present study we examined whether cells that do not express the L4F3 antigen include precursors of hematopoietic colony-forming cells. Colony-forming cells were depleted from marrow by treatment with L4F3 and complement. The remaining cells generated CFU-GM, BFU-E, and CFU-Mix when cultured in the presence of irradiated adherent cell layers from long-term marrow cultures. Marrow cells not expressing the L4F3 antigen, which were separated by cell-sorting techniques, were depleted of colony-forming cells but nevertheless generated CFU-GM when cultured over irradiated adherent cell layers. These data suggest that there are marrow precursors that do not express the L4F3 antigen and that give rise to colony-forming cells of multiple types. Negative selection techniques should allow the enrichment of these precursors of colony-forming cells, thereby enabling direct studies of these immature stem cells.  相似文献   
84.
Freezing of gait (FOG) in Parkinson’s disease (PD) likely results from dysfunction within a complex neural gait circuitry involving multiple brain regions. Herein, cerebellar activity is increased in patients compared to healthy subjects. This cerebellar involvement has been proposed to be compensatory. We hypothesized that patients with FOG would have a reduced ability to recruit the cerebellum to compensate for dysfunction in other brain areas. In this study cerebellar activity was modified unilaterally by either excitatory or inhibitory theta burst stimulation (TBS), applied during two separate sessions. The ipsilateral cerebellar hemisphere, corresponding to the body side most affected by PD, was stimulated. Seventeen patients with PD showing ‘off’ state FOG participated. The presence of FOG was verified objectively upon inclusion. We monitored gait and bimanual rhythmic upper limb movements before and directly after TBS. Gait was evaluated with a FOG-provoking protocol, including rapid 360° turns and a 10-m walking test with small fast steps. Upper limb movement performance was evaluated with a repetitive finger flexion–extension task. TBS did not affect the amount of freezing during walking or finger tapping. However, TBS did increase gait speed when walking with small steps, and decreased gait speed when walking as fast as possible with a normal step size. The changes in gait speed were not accompanied by changes in corticospinal excitability of M1. Unilateral cerebellar TBS did not improve FOG. However, changes in gait speed were found which suggests a role of the cerebellum in PD.  相似文献   
85.

Purpose

Until now there are no systematic studies about the long-term course of myoma growth. Therefore, the aims of the present study were: (1) ultrasound monitoring of the natural course of growth of uterine leiomyomas; (2) assessment of whether the growth of myomas depends on the age of the patients, the location, or the initial size (possible co-factors/predictor criteria for increase of growth); influence of oral contraceptives (OC).

Methods

Patient records (2010–May 2016) were retrospectively and systematically evaluated in regards to their growth and clinical course. The patients received a follow-up questionnaire by mail about the further history. Linear regression analysis and generalized regression analysis were performed to determine the influence of various factors on the growth of myomas.

Results

Overall, 152 met the further inclusion criteria. Most of the myomas increased in size but 10% of the myomas became smaller without therapy. There is a significant dependency between the initial myoma size, and the first and second measurements, but not between those measures and myoma localization. In regression analysis, there was also a significant association between the growth of the myomas and the initial size but no association with age, complaint symptoms, and use of OC. However, the use of OC waas significantly associated with myoma growth in GEE.

Conclusions

The course of growth of myomas has large variance, so this should not be taken as a sign for a malignant event (sarcoma or the so-called STUMP). The growth takes place with considerable individual variability and ultimately is not predictable.
  相似文献   
86.
Substance use is associated with impaired social cognition. Experimental studies have shown that acute intoxication of alcohol, tobacco, and cannabis decreases the performance in non-verbal, social communication and theory of mind tasks. However, in epidemiological studies the temporal direction of this association has gone relatively unstudied. We investigated both directions of association within an adolescent birth cohort: the association of social cognition with subsequent substance use, and the association of early substance use with subsequent social cognition. We used data from the Avon Longitudinal Study of Parents and Children, a UK birth cohort. Logistic regression indicated that poor childhood non-verbal communication was associated with decreased odds of adolescent alcohol (OR 0.70, 95% 0.54–0.91), tobacco (OR 0.62, 95% CI 0.47–0.83), and cannabis use (OR 0.62, 95% CI 0.46–0.83). Early adolescent substance use was associated with increased odds of poor social communication (alcohol: OR 1.46, 95% CI 0.99–2.14; tobacco: OR 1.95, 95% CI 1.33–2.86) and poor social reciprocity (alcohol: OR 1.57, 95% CI 1.18–2.09; tobacco: OR 1.92, 95% CI 1.43–2.58; cannabis: OR 1.54, 95% CI 1.16–2.05). Overall, the relationship between social cognition and substance use was different in each temporal direction. Poor non-verbal communication in childhood appeared protective against later substance use, while adolescent substance use was associated with decreased social cognitive performance.  相似文献   
87.
88.
The use of prophylactic anti-D to prevent Rh D immunization in Rh D- women and subsequent hemolytic disease in Rh D+ infants is widespread, but has led to shortages of the anti-D Ig. With the aim of substituting monoclonal anti-D for Rh D prophylaxis, we have compared the abilities of monoclonal and polyclonal anti-D to clear Rh D+ red blood cells (RBCs) infused into Rh D- male volunteers and to suppress Rh D immunization. Two human monoclonal antibodies (MoAbs), BRAD-3 (IgG3) and BRAD-5 (IgG1), produced from stable Epstein-Barr virus-transformed B-lymphoblastoid cell lines, were selected because of their proven in vitro activity in promoting RBC lysis in antibody-dependent cell- mediated cytotoxicity assays. RBC clearance was assessed by intravenous injection of 3 mL of 51chromium-labeled D+ RBCs into 27 volunteers 48 hours after intramuscular injection of monoclonal or polyclonal anti-D. Further 3-mL injections of unlabeled D+ cells were administered at 6 and 9 months to induce immunization. Blood samples were taken throughout the 12-month period of study for the serologic detection of anti-D. The mean half-life (t50%) of RBCs in 7 recipients of 300 micrograms BRAD-5 (5.9 hours) was similar to that in 8 recipients of 500 IU polyclonal anti-D (5.0 hours), whereas D+ cells were cleared more slowly in some of the 8 subjects injected with 300 micrograms BRAD- 3 (mean t50% 12.7 hours) and in 1 individual administered 100 micrograms BRAD-3 (t50% 41.0 hours). The rate of RBC clearance in both groups administered 300 micrograms monoclonal anti-D correlated with the amount of antibody bound per cell, determined by flow cytometry. There was no evidence of primary immunization having occurred in any subject after 6 months of follow-up. Five of 24 subjects produced anti- D after one or two further injections of RBCs, confirming that they were responders who had been protected by the monoclonal or polyclonal anti-D administered initially. Four of these responders were recipients of monoclonal anti-D (3 BRAD-3, 1 BRAD-5). One individual who received BRAD-5 produced accelerated clearance of D+ RBCs at the third unprotected RBC challenge but did not seroconvert. This study shows that the human MoAbs BRAD-3 and BRAD-5 can prevent Rh D immunization, and indicates that they may be suitable replacements for the polyclonal anti-D presently used in prophylaxis of Rh D hemolytic disease of the newborn.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
89.
BACKGROUND: Resistance training (RT) is safe and practicable in low-risk populations with coronary artery disease. In patients with left ventricular (LV) dysfunction after an acute ischaemic event, few data exist about the impact of RT on LV remodelling. METHODS: In this prospective, randomized, controlled study, 38 patients, after a first myocardial infarction and a maximum ejection fraction (EF) of 45%, were assigned either to combined endurance training (ET)/RT (n=17; 15 men; 54.7+/-9.4 years and EF: 40.3+/-4.5%) or to ET alone (n=21; 17 men; 57.0+/-9.6 years and EF: 41.9+/-4.9%) for 12 weeks. ET was effectuated at an intensity of 70-85% of peak heart rate; RT, between 40 and 60% of the one-repetition maximum. LV remodelling was assessed by MRI. RESULTS: No statistically significant differences between the groups in the changes of end-diastolic volume (P=0.914), LV mass (P=0.885) and EF (P=0.763) were observed. Over 1 year, the end-diastolic volume increased from 206+/-41 to 210+/-48 ml (P=0.379) vs. 183+/-44 to 186+/-52 ml (P=0.586); LV mass from 149+/-28 to 155+/-31 g (P=0.408) vs. 144+/-36 to 149+/-42 g (P=0.227) and EF from 49.1+/-12.3 to 49.3+/-12.0% (P=0.959) vs. 51.5+/-13.1 to 54.1% (P=0.463), in the ET/RT and ET groups, respectively. Peak VO2 and muscle strength increased significantly in both groups, but no difference between the groups was noticed. CONCLUSION: RT with an intensity of up to 60% of the one-repetition maximum, after an acute myocardial infarction, does not lead to a more pronounced LV dilatation than ET alone. A combined ET/RT, or ET alone, for 3 months can both increase the peak VO2 and muscle strength significantly.  相似文献   
90.

Purpose

It has been proposed that biological/chemical substances in the intestine might play a role in the occurrence and deterioration of perianal fistulas. Elimination of such unidentified factors from the lower gastrointestinal tract might offer a new strategy for the management of anal fistulas. The aim of this study was to evaluate the clinical effects on non-Crohn’s disease perianal fistula healing, and the safety and tolerability of a new medical device that applies high-purity, high-activity granular activated carbon locally into the rectum twice daily of patients with perianal fistulas without any concomitant medication.

Methods

An open, single-arm, prospective study with active treatment for 8 weeks and an optional follow-up until week 24 (ClinicalTrial.gov identifier NCT01462747) among patients with chronic, uncomplicated perianal fistulas scheduled for surgery was conducted.

Results

Of 28 patients included, 10 patients (35.7%) showed complete fistula healing (closed, no discharge on palpation) after 8 weeks; seven of these patients, corresponding to 25% of the enrolled patients, remained in remission for up to 31 weeks. At week 8, there was a statistically significant reduction in the discharge visual analog scale (p = 0.04), a significant improvement in the patient-perceived quality of life for the category of embarrassment (p = 0.002), and a trend toward improvement in the other assessment categories.

Conclusions

The treatment was well tolerated, and patient acceptance was high. The results support the efficacy and safety of locally administered activated carbon for the treatment of patients with chronic uncomplicated perianal fistulas not receiving any other medication for fistula problems.
  相似文献   
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