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排序方式: 共有891条查询结果,搜索用时 0 毫秒
1.
D R Burke M H Torosian G K McLean S G Meranze E F Rosato 《JPEN. Journal of parenteral and enteral nutrition》1988,12(2):225-226
The problem of protein calorie malnutrition following major gastrointestinal surgery can be treated with central venous or enteric alimentation, with the latter being preferred. The authors describe a simple technique for the conversion of biliary stents placed after pancreaticoduodenal surgery into jejunal feeding tubes when the stenting function is no longer needed. Three illustrative cases are presented. In each case, the procedure took less than 30 min and had no associated morbidity. This technique allows early conversion from central venous to enteric alimentation without the need to create a second surgical enterostomy. 相似文献
2.
V P Addonizio C A Fisher J F Strauss V A Ewan F R Rickles E F Rosato A H Harken W Y Inouye 《Surgery》1987,101(6):753-762
Disseminated intravascular coagulation invariably accompanies placement of peritoneovenous (LeVeen) shunts, which suggests that ascitic fluid contains procoagulant material capable of activating blood coagulation. In this study, we identified thrombogenic activity in human ascites and the hemostatic pathway by which it acts. Peritoneal fluid was removed percutaneously from patients with ascites due to various causes. Four fractions were prepared by centrifugation: cells, a low-speed, cell-free fluid, a high-speed supernatant, and the precipitate from the high-speed centrifugation. Cellular fractions from all ascitic fluids shortened a one-stage clotting time of normal pooled plasma by 68% in comparison with saline solution and endotoxin controls. Similarly, the cell-free fluids also shortened the clotting time of normal pooled plasma by 41%. The cellular and cell-free fractions shortened the clotting time of factor VIII-deficient plasma but failed to demonstrate procoagulant activity in factor VII-deficient plasma. These fractions had no effect on platelet aggregation or the platelet release reaction. The high-speed precipitate was dissociated by ethylenediaminetetra-acetate (EDTA) into fluid phase and precipitate, both of which demonstrated procoagulant activity. Furthermore, high-speed precipitate contained protein, phospholipid, and sterol in proportions similar to those of plasma membranes and contained membrane-bound vesicles as identified by means of electron microscopy. This material could be rendered inactive by heating to 100 degrees C for 2 minutes or by incubation with phospholipase C for 15 minutes. Finally, the ability of the high-speed precipitate to shorten the clotting time was prevented by preincubation with a monoclonal antibody, which is known to inhibit the procoagulant activity of human tissue factor. We suggest that several entities contribute to the procoagulant properties of human ascites, with procoagulant material deriving at least in part from peritoneal cells. The sedimentable procoagulant factor appears to be associated with cellular membranes or membrane fragments and is thromboplastin-like in its chemical composition, immunoreactivity, and substrate specificity. 相似文献
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.
Summary Selection of populations of Tacaribe virus strain 11573 lethal for mice was carried out by serial intracerebral passage of the virus in adult mice. Viral populations have been characterized by determination of virulence for suckling, weanling, and adult mice, and by histopathologic changes observed in brains of adult mice after intracerebral inoculation. Some of the virus preparations produced 80 to 90 per cent mortality after two or three intracerebral passages in adult mice and maintained this virulence for 1 to 3 passages, after which the virulence rapidly declined with subsequent passages. Clinical signs of infection in adult mice were manifested by a rough hair-coat, ventriflexed posture, diminished activity, increased excitability, flaccid hind-limb extension with progressive paralysis and death. Histologic examination revealed meningoencephalitis.With 2 FiguresIn conducting the research described in this report, the investigators adhered to the Guide for the Care and Use of Laboratory Animals, as promulgated by the Committee on the Revision of the Guide for Laboratory Animal Facilities and Care of the Institute of Laboratory Animal Resources, National Research Council. The facilities are fully accredited by the American Association for Accreditation of Laboratory Animal Care.The views of the authors do not purport to reflect the positions of the Department of the Army or the Department of Defense. 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.
Angiography in poor-risk patients with massive nonvariceal upper gastrointestinal bleeding 总被引:4,自引:0,他引:4
D T Dempsey D R Burke R S Reilly G K McLean E F Rosato 《American journal of surgery》1990,159(3):282-286
The purpose of this retrospective study was to determine the diagnostic and therapeutic usefulness of gut angiography in patients with massive upper gastrointestinal bleeding from a nonvariceal source. All patients (n = 64) in this category who underwent a gut angiogram between 1980 and 1986 were studied. Pre-angiogram endoscopy was attempted in all patients and was nondiagnostic in 14 (22%). Contrast extravasation at angiography was seen in 25 of 64 patients (39%), and in over half of these patients endoscopy was nondiagnostic (n = 11) or wrong (n = 3). Attempts to control bleeding in this group by selective arterial embolization (n = 14) or intra-arterial vasopressin (n = 11) successfully averted operation in 13 of 25 patients (52%) and was associated with a 50% reduction in mortality (83% versus 38%). Selective embolization of vessels thought to be bleeding on clinical grounds without evidence of contrast extravasation (i.e., "blind" embolization) was not helpful in controlling hemorrhage. Urgent gut angiography in patients with massive upper gastrointestinal bleeding of arteriocapillary source is a useful diagnostic and therapeutic maneuver and warrants continued application in this group of poor-risk patients. 相似文献
8.
Objectives. To examine the incidence of cancers among persons born in Scotland, Northern Ireland, the Irish Republic, Caribbean Commonwealth and Indian subcontinent and living in England and Wales. Methods. Longitudinal Study of 1% of population of England and Wales followed from 1971 to 1989. Standardised incidence ratios (SIRs) were derived for commonly occurring cancers and all cancers using the age-sex-specific rates for all females and all males in the Longitudinal Study. Results. The incidence of all malignant neoplasms among West Indians (females SIR = 67, male SIR = 70) and Indians (female SIR = 32, male SIR = 52) was low. Among South Asians, this pattern was consistent for Hindus, Sikhs and Moslems. Scottish females showed raised incidence of lung cancer (SIR = 149) and those from the Irish Republic of oral cavity and pharynx (SIR = 321), oesophageal (SIR = 219) and liver (SIR = 373) cancers. Among Northern Irish females, incidence of lung cancer (SIR = 193) was raised. West Indian and South Asian females showed low incidence of breast cancer (SIR = 55 and 45, respectively). High incidence of laryngeal (SIR = 229) and renal (SIR = 203) cancers was observed for Scottish males and of oral cancer (SIR = 259) for males from the Irish Republic. At ages 15-64, raised incidence of prostate cancer (SIR = 129) and of leukaemia (SIR = 252) was also observed for men from the Irish Republic. Northern Irish males showed raised incidence of stomach cancer (SIR = 200). Conclusion. This study describes patterns of cancer incidence among migrant groups, most of which reflect environmental influences. This has challenging implications for sensitive targeting of primary interventions. It is important not to be complacent about lower risks of main cancers among West Indians and South Asians. In all Longitudinal Study members, breast cancer was the most common malignancy among females and lung cancer among males. This was also true for all migrant groups with the exception of Northern Irish women for whom lung cancer was the most common. 相似文献
9.
Neil E Martin Thomas B Brunner Krystina D Kiel Thomas F DeLaney William F Regine Mohammed Mohiuddin Ernest F Rosato Daniel G Haller James P Stevenson Debbie Smith Barnali Pramanik Joel Tepper Wesley K Tanaka Briggs Morrison Paul Deutsch Anjali K Gupta Ruth J Muschel W Gillies McKenna Eric J Bernhard Stephen M Hahn 《Clinical cancer research》2004,10(16):5447-5454
PURPOSE: Preclinical and clinical studies have demonstrated that inhibition of prenylation can radiosensitize cell lines with activation of Ras and produce clinical response in patients with cancer. The aim of this study was to determine the maximally tolerated dose of the dual farnesyltransferase and geranylgeranyltransferase I inhibitor L-778,123 in combination with radiotherapy for patients with locally advanced pancreatic cancer. EXPERIMENTAL DESIGN: L-778,123 was given by continuous intravenous infusion with concomitant radiotherapy to 59.4 Gy in standard fractions. Two L-778,123 dose levels were tested: 280 mg/m2/day over weeks 1, 2, 4, and 5 for dose level 1; and 560 mg/m2/day over weeks 1, 2, 4, 5, and 7 for dose level 2. RESULTS: There were no dose-limiting toxicities observed in the eight patients treated on dose level 1. Two of the four patients on dose level 2 experienced dose-limiting toxicities consisting of grade 3 diarrhea in one case and grade 3 gastrointestinal hemorrhage associated with grade 3 thrombocytopenia and neutropenia in the other case. Other common toxicities were mild neutropenia, dehydration, hyperglycemia, and nausea/vomiting. One patient on dose level 1 showed a partial response of 6 months in duration. Both reversible inhibition of HDJ2 farnesylation and radiosensitization of a study patient-derived cell line were demonstrated in the presence of L-778,123. K-RAS mutations were found in three of the four patients evaluated. CONCLUSIONS: The combination of L-778,123 and radiotherapy at dose level 1 showed acceptable toxicity in patients with locally advanced pancreatic cancer. Radiosensitization of a patient-derived pancreatic cancer cell line was observed. 相似文献
10.