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排序方式: 共有481条查询结果,搜索用时 31 毫秒
1.
E. Kochs 《Der Anaesthesist》1997,46(12):1024-1025
Ohne Zusammenfassung 相似文献
2.
3.
Steenbergen EJ; Verhagen OJ; van Leeuwen EF; van den Berg H; von dem Borne AE; van der Schoot CE 《Blood》1995,86(2):692-702
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL. 相似文献
4.
Michael B Leahy Johannes T Dessens Friedemann Weber Georg Kochs Patricia A Nuttall 《Virus research》1997,50(2):215-224
The tick-borne Thogoto virus (THOV) is the type species of a newly recognized fourth genus, Thogotovirus, in the family Orthomyxoviridae. Because of the distant relationship of THOV with the influenza viruses, determination of its genomic information can potentially be used to identify important domains in influenza virus proteins. We have determined the complete nucleotide sequence of the second longest RNA segment of THOV. The molecule comprises 2212 nucleotides with a single large open reading frame encoding a protein of 710 amino acids, estimated Mr 81 284. The protein shares 77% amino acid similarity with the PB1-like protein of Dhori virus, a related tick-borne virus, and 50–53% with the PB1 polymerase proteins of influenza virus A, B and C. All the motifs characteristic of RNA-dependent polymerases were identified including the SSDD motif common to all RNA-dependant RNA polymerases, indicating that the THOV protein is functionally analogous to the influenza virus PB1 proteins and involved in chain elongation. We also report the corrected sequence of the third longest RNA segment of THOV, encoding a protein which shares 44–47% amino acid similarity with the PA-like polymerase proteins of influenza virus A, B and C. The biological significance of conserved domains in these orthomyxovirid proteins is discussed. 相似文献
5.
Fugger EF; Black SH; Keyvanfar K; Schulman JD 《Human reproduction (Oxford, England)》1998,13(9):2367-2370
The world's first deliveries of normal babies after use of flow cytometric
separated human sperm cells (MicroSort) for preconception gender selection
are reported. Offspring were of the desired female gender in 92.9% of the
pregnancies. Most of these pregnancies and births were achieved after
simple intrauterine insemination.
相似文献
6.
Detecting pre-ovulatory luteinizing hormone surges in urine 总被引:2,自引:1,他引:2
Kesner JS; Knecht EA; Krieg EF Jr; Wilcox AJ; O'Connor JF 《Human reproduction (Oxford, England)》1998,13(1):15-21
The study objectives were to determine (i) if pre-ovulatory luteinizing
hormone (LH) surges, undetected in urine by two immunoradiometric assays
(IRMA), were detectable by an ultrasensitive immunofluorometric assay
(IFMA) and (ii) the influence of creatinine adjustment on the detection and
timing of the urinary LH surges. Daily urine specimens were contributed by
healthy 25-36 year old volunteers during 14 ovulatory menstrual cycles for
an epidemiological study conducted in 1983-1985. Specimens were selected as
having been previously assayed by two IRMA without consistently detecting
LH surges. These urine specimens were remeasured using an IFMA and adjusted
for creatinine concentration. IFMA measurements revealed unambiguous LH
surges in all cycles. Adjusting IRMA urinary LH values for creatinine
concentrations revealed previously undetected LH surges in four of eight
cycles. Creatinine adjustment also altered the timing of IRMA and IFMA LH
surges by 1-5 days. These results demonstrate an IFMA that detects pre-
ovulatory LH surges in unpreserved, frozen urine from cycles where such
surges were previously undetectable. Further, creatinine adjustment can
markedly affect detection and timing of the onset and peak of the urinary
LH surge. While our analysis suggests that this adjustment improves the
validity of the LH measure, this requires further investigation.
相似文献
7.
C. Haug A. Metzele J. Steffgen M. Kochs V. Hombach A. Grünert 《Journal of molecular medicine (Berlin, Germany)》1994,72(6):430-434
Brain natriuretic peptide (BNP) and atrial natriuretic peptide (ANP) plasma concentrations were measured in patients with dialysis-dependent chronic renal failure and in patients with coronary artery disease exhibiting normal or elevated left ventricular end-diastolic pressure (LVEDP) (n = 30 each). Blood samples were obtained from the arterial line of the arteriovenous shunt before, 2 h after the beginning of, and at the end of hemodialysis in patients with chronic renal failure. In patients with coronary artery disease arterial blood samples were collected during cardiac catheterization. BNP and ANP concentrations were determined by radioimmunoassay after Sep Pak C18 extraction. BNP and ANP concentrations decreased significantly (P < 0.001) during hemodialysis (BNP: 192.1 ± 24.9, 178.6 ± 23.0, 167.2 ± 21.8 pg/ml; ANP: 240.2 ± 28.7, 166.7 ± 21.3, 133.0 ± 15.5 pg/ml). The decrease in BNP plasma concentrations, however, was less marked than that in ANP plasma levels (BNP 13.5 ± 1.8%, ANP 40.2 ± 3.5%; P < 0.001). Plasma BNP and ANP concentrations were 10.7 ± 1.0 and 60.3 ± 4. 0 pg/ml in patients with normal LVEDP and 31.7 ± 3.6 and 118.3 ± 9.4 pg/ml in patients with elevated LVEDP. These data demonstrate that BNP and ANP levels are strongly elevated in patients with dialysis-dependent chronic renal failure compared to patients with normal LVEDP (BNP 15.6-fold, ANP 2.2-fold, after hemodialysis; P < 0.001 or elevated LVEDP (BNP 6.1-fold, ANP 2.0-fold, before hemodialysis; P < 0.001), and that the elevation in BNP concentrations was more pronounced than that in ANP plasma concentrations. The present results provide support that other factors than volume overload, for example, decreased renal clearance, are also involved in the elevationin BNP and ANP plasma levels in chronic renal failure. The stronger elevation in BNP concentrations in patients with chronic renal failure and in patients with elevated LVEDP and the less pronounced decrease during hemodialysis suggest a different regulation of BNP and ANP plasma concentrations.[/ p]Abbreviations ANP
atrial natriuretic peptide
- BNP
brain natriuretic peptide
- LVEDP
left ventricular end-diastolic pressure
Correspondence to: C. Haug 相似文献
8.
High frequency jet ventilation (HFJV) was used in 68 patients which were treated with extracorporal shock wave lithotripsy (ESWL) because of stone diseases in the upper urinary tract. The question was whether HFJV in combination with a semiclosed conventional circle system offered a practicable and safe technique to minimize the oscillations which are proportional to the applied tidal volume and to the diaphragmatic movements. With IPPV the mean distance of the stone movement was 32 mm, whereas with the application of HFJV the stones oscillated around their resting position within limits of 2 to 3 mm (ventilation frequency: 200-300/min, driving pressure: 0.6-1.1 bar, tidal volume: 3-8 1/min). The effectiveness of HFJV was monitored by the end-tidal carbon dioxide tension (PeCO2) during intermittently conventional ventilation with "adequate" tidal volumes (TV 15 ml/kg bw). The correlation between PeCO2 and simultaneous measured PaCO2 was r = 0,91. The application of HFJV enhances the efficiency of ESWL. So the treatment of stones of the upper urinary tract can be varied by more subtle dosage of the incoming shock wave energy and by stabilisation of the stones in the underlying ellipsoid of the energy focus. 相似文献
9.
María Jesús Fernández Aceñero MD PhD Cristina Díaz del Arco CDdA MD Carme Dinarés CD MD PhD Tania Labiano TL MD Eva Tejerina ET MD PhD Mª José Bernabé MJ B MD Elena Forcen EF MD Melchor Saiz-Pardo MSP MD Pablo Pérez PP MD Maria D. Lozano MDL MD PhD 《Diagnostic cytopathology》2023,51(1):26-35
Lung carcinoma remains one of the most frequent and aggressive human neoplasms. Fortunately, in the last decades, the increasing knowledge of the molecular mechanisms leading to cancer development has allowed the use of targeted therapies with improvement of prognosis in many patients. Clinical management has also changed after the introduction of endobronchialultrasonographic bronchoscopy that allows a conservative staging of lung tumors, avoiding the need of mediastinoscopy for lymph node staging. Lung pathologists and cytopathologists are facing the challenge of giving the more comprehensive prognostic and predictive information with ever smaller tissue or cytological samples. The aim of this review is to summarize the molecular testing for non-small cell lung carcinoma and how pathologists can contribute to the patient's outcome with a conscious management of biological samples. 相似文献
10.
The most notable limitations of balloon dilatation, acute vascular occlusion with a rate of 3 to 5% and restenosis rate of 20 to 40%, appear at least partially attributable to the mechanism of luminal widening--tearing of the intima and plastic restructuring of plaque material. Alternative angioplasty methods, with the exception of stent implantation, are based on the concept of rendering plaque material, by excision and ablation, with a smoother and less thrombogenic interior surface and to lower the risk of renewed proliferation. Plaque material is removed in three ways: mechanical, by excision; thermically, by laser with relatively low energy density or by high-frequency alternating current; non-thermically, by photoablation with laser of very high energy impulse density. High-frequency alternating current as an energy source for thermic angioplasty is used in four technically different forms of application (Table 1): as indirect or direct high-frequency angioplasty in the scope of the "spark erosion" technique and for heating a balloon during balloon dilatation to achieve thermofusion of the tissue for stabilization of the angioplasty results. With indirect hot-tip high-frequency angioplasty the high-frequency alternating current is employed to rapidly heat an olive-shaped fully isolated metal tip with an integrated resistor, plated with gold to avoid adhesion of thrombotic material. The heat emitted is directed radially. The currently-available system consists of a 20-Watt high-frequency generator with 5 MHz. On application of 10 Watts to tissue in water at 37 degrees C, the temperature achieved at the catheter tip is 130 to 140 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献