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H J Neumann

Publications and source records attributed to H J Neumann.

At least 37 records · Page 2Linked to original sources
PubMed1993

Multicenter study of standardization of cell counting. Haemapheresis Scientific Workshop Group of DGTI.

Multicenter studies on cell separators give valid data (which can be compared between the different centers) only if the cell counting methods are uniform. This has to be demonstrated by ring studies or multicenter counting studies. Twelve apheresis centers involved in a multicenter study for the evaluation of the Fresenius AS 104 cell separator participated in such a ring study from July 1990 to July 1991. The twelve participating centers split into three significantly different groups according to the platelet counts in the platelet concentrates and a calculated pseudo extraction efficiency. No differences could be found in the white and red blood cell counts. No mailing effect--or time effect--and no personal effect could be found in the reference center.

Blood Component Removal↗
PubMed1993

[Preliminary results of the 2nd multicenter study. Thrombocytapheresis with the Fresenius AS-104 blood cell separator and ring study of cell counting. Section of Therapeutic and Preparative Hemapheresis of the DGTI].

Only multicenter studies on cell separators give valid data to compare different cell separators. The aim of the 2nd multicenter study was to evaluate the separation protocol, software version V 4.61, of the Fresenius AS-104 cell separator for efficiency and deviation from predicted yields. Plateletpheresis data from twelve hemapheresis centers, using identical apheresis protocols and cell counting methods, were registered and statistically analyzed. Additionally, the counting methods of the centers were controlled by a ring study with biweekly external cell count trials. To get a comparison, the apheresis data, which depend on the center effects, were corrected by the values from the ring study. Preliminary results of 380 runs are 45.2 +/- 8.1% for the separation effectivity, 1.95% deviation from the predicted yield, whereby 90% of all runs deviated less than 20% from the predicted yield. 50% of products had a WBC contamination below 6 x 10(6).

Blood Volume↗
PubMed1993

German multicenter studies on plateletpheresis from healthy donors. German Hemapheresis Study Group.

It is reported on two German Multicenter Plateletpheresis Studies with the Fresenius AS 104 cell separator accompanied by a Multicenter Counting Study. 15 centers participated, a total of 1884 separations were evaluated. It could be shown that multicenter studies help to give a more objective opinion about a cell separator and the separation protocol used if it is possible to improve the counting methods and to eliminate individual center effects by an accompanying Multicenter Counting Study. The AS 104 proved to be a good cell separator for platelet collection regarding platelet yields (3.1 x 11" from 3.5 I citrated blood), separation efficiency (about 45%), yield prediction (SD = not equal to 15%) and leukocyte contamination (median WBC 47 x 10(6)).

Blood Donors↗
PubMed1992

New polyolefin foil for 5-day storage of platelet concentrates (PC) collected by apheresis.

In a paired study 12 platelet concentrates (PC) of Fresenius AS-104 cell separator were stored in new polyolefin bags of Fresenius (LE2) and Fenwal PL-732 bags. On day 0 and after 3 and 5 days of storage pH, pO2, pCO2, cell counts, platelet morphology and aggregability, plasma glucose, lactate, LDH and beta TG were determined. The overall changes fell within the expected range. No relevant differences between the two bags could be detected, although a few parameters (pH, pCO2) are slightly but statistically/significantly different. It can be concluded that the new polyolefin bag is well suited for 5-day storage of PC's from the AS-104.

Blood Preservation↗
PubMed1989

[Stimulation of prenatal development in laboratory animals by nootropics].

Described in this paper is the use of nootropics for stimulation of prenatal development of laboratory animals. Investigations, in that context, led to the discovery of so far unknown and unexpected properties of this group of medicaments. Foetal weight gain, reduction of teratogenicity, and decrease in implantation loss proved to be some of them.

Animals↗
PubMed1989

[CHILD syndrome--a case report for understanding this rare genetic dermatosis].

CHILD syndrome in a 4 6/12 years old girl with manifestation of the typical unilateral ichthyosiform erythroderma and hypoplasia of the left arm and leg after birth is reported. The symptoms are listed in a table for comparison to other publications. The moderate shortening of the mother's left arm has significance to the unclear mode of heredity. Local therapy with vitamin A acid brought a satisfactory result. Finally, a short reference is given to a new case from another kindred.

Child, Preschool↗
PubMed1988

Early evening ranitidine administration promotes faster duodenal ulcer healing.

In a prospective double-blind clinical trial, 141 patients with endoscopically diagnosed duodenal ulcer were randomly assigned to treatment with ranitidine 300 mg, taken either at 6 PM or at 10 PM. After 2 wk of treatment, 52 of 70 patients (74%) in the 6 PM treatment group had healed, compared with 32 of 64 patients (50%) taking ranitidine at 10 PM (p less than 0.01). After 4 wk, the cumulative healing rates were 100% and 94%, respectively, for the 6 PM and 10 PM treatment regimens. These results suggest that ranitidine, taken as a single daily 300-mg dose at 6 PM after dinner, provides more rapid duodenal ulcer healing than the same dose of the drug taken at 10 PM.

Adolescent↗
PubMed1987

Improvement of the safety systems in cell separators. The new safety concept for the cell separator AS 104 (Fresenius).

The new, extended safety requirements for cell separators call for a new generation of machines to address current safety needs. In order to ensure safe treatment, the complete safety concept is of decisive importance - this includes closed seal-less systems, continuous operation, fractions collected externally to the centrifuge, and pump tubings, connections and clamps which are color and direction coded. 'Human failure' as a cause of fault should be excluded for these highly technical appliances - for example, through the use of 'fail-safe' circuits, drip-controlled ACD flow by a separate adjustable pump, detection of damages to blood components by hemolysis control.

Blood Component Removal↗