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91.
Two cases of fetal perirenal uriniferous pseudocyst were diagnosed in utero with ultrasound studies. The perirenal collections resolved spontaneously in utero. Follow-up examination showed growth impairment of the affected kidney. At birth, no renal function was demonstrated in one case and only slight function in the other case. Pathologic examination showed a highly dysplastic kidney with extravasated urine in the case in which surgery was performed. Some hypodysplastic kidneys apparently result from acute in utero obstruction with secondary pyelocalyceal rupture. Renal dysplasia could render the kidney more vulnerable to such phenomena.  相似文献   
92.
过去对脉管疾病的描述往往将血管瘤和脉管畸形相混淆,从而导致不恰当的治疗及医学文献记录的矛盾。Mulliken和Glowacki系统描述了血管瘤和脉管畸形的差别,认为血管瘤是真正的肿瘤,在组织学上表现为细胞增殖。在治疗方面文献报道也存在不同,有人认为血管瘤可以完全自行消退,而部分文献却主张对病变进行干预。最近.对血管瘤自然病程研究增多,并对血管瘤是观察还是干预的选择进行了讨论,设计了安全有效的治疗方案。该文分2部分,第1部分结合新近文献,综述血管瘤的诊断及其自然病程,并与旧的文献作了比较。第2部分介绍了血管瘤是治疗还是观察的原则,推荐治疗方法,并着重论述了外科技术。  相似文献   
93.
Technetium-99m pyridoxylideneglutamate (P.G.) cholescintigraphy   总被引:1,自引:0,他引:1  
  相似文献   
94.
95.
We have developed a methodology we call ROMA (representational oligonucleotide microarray analysis), for the detection of the genomic aberrations in cancer and normal humans. By arraying oligonucleotide probes designed from the human genome sequence, and hybridizing with "representations" from cancer and normal cells, we detect regions of the genome with altered "copy number." We achieve an average resolution of 30 kb throughout the genome, and resolutions as high as a probe every 15 kb are practical. We illustrate the characteristics of probes on the array and accuracy of measurements obtained using ROMA. Using this methodology, we identify variation between cancer and normal genomes, as well as between normal human genomes. In cancer genomes, we readily detect amplifications and large and small homozygous and hemizygous deletions. Between normal human genomes, we frequently detect large (100 kb to 1 Mb) deletions or duplications. Many of these changes encompass known genes. ROMA will assist in the discovery of genes and markers important in cancer, and the discovery of loci that may be important in inherited predispositions to disease.  相似文献   
96.
Zuckerman  KS; Case  DC Jr; Gams  RA; Prasthofer  EF 《Blood》1993,82(12):3564-3573
An intensive chemotherapy regimen (EVDAC), including high-dose epirubicin, vincristine, and dexamethasone followed by cyclophosphamide and high-dose cytarabine, was administered to 54 untreated adults with intermediate or high-grade non-Hodgkin's lymphomas (NHL). The median age was 59, 61% were Ann Arbor Stage IV, 57% had "B" symptoms, 50% had serum lactate dehydrogenase greater than 250 U/L, and 48% had masses greater than 7 cm (33% > 10 cm) in diameter. Seventy-six percent of patients attained complete or probable complete remissions. The Kaplan- Meier actuarial failure-free survival at 7 years is 50%, and 59% (32 of 54) of all patients started on therapy remain alive and in first remission at a median of 62+ (range, 49+ to 76+) months from completion of therapy. Nearly all patients developed severe neutropenia. Febrile episodes requiring hospitalization during neutropenia occurred after 56% of courses of epirubicin, vincristine, and dexamethasone and after 9% of courses of cyclophosphamide and cytarabine; 80% of patients were hospitalized at least once. Platelet count nadirs of less than 20,000/microL occurred after only 1 of 146 evaluable courses of epirubicin and after none of the cyclophosphamide/cytarabine courses. Although 8 patients had decreases of at least 0.12 in their left ventricular ejection fractions (5 to below normal levels), none have developed clinically evident congestive heart failure. Clinically significant mucositis occurred after only 8% of courses of high-dose epirubicin. Three deaths from infections and one from hyperkalemia with cardiac arrest occurred during therapy. These results confirm that high remission and sustained, failure-free survival rates can be achieved in patients with aggressive NHL, using high-dose anthracycline-containing chemotherapy regimens. Epirubicin appears to have an advantage over doxorubicin at high doses because of decreased toxicity at a therapeutically equivalent dose. These phase II study results need to be validated in a randomized phase III trial, and growth factors should be used to attempt to reduce the neutropenia-associated complications.  相似文献   
97.
OBJECTIVE: To investigate preterm infants, we have installed in our neonatal intensive care unit a dedicated magnetic resonance (MR) imaging system which was specifically designed for neonatal use. The aim of this study was to describe the MR appearances of the brain in preterm infants who were first scanned between 25 and 32 weeks gestational age (GA) and to outline changes to the brains of these infants between their first scan and term. METHODS: Preterm infants of 25 to 32 weeks GA were imaged using the 1T neonatal MR system (Oxford Magnet Technology, Eyensham, Oxfordshire, England/Picker International, Cleveland, OH). The scanning protocol included T1-weighted conventional spin echo (repetition time [TR], 600; echo time, 20 ms), inversion recovery fast spin echo (TR, 3530; effective echo time, 30; inversion time, 950 ms), and T2-weighted fast spin echo (TR, 3500; effective echo time, 208 ms) sequences. RESULTS: Seventeen infants of median 28 weeks GA (range, 24 to 31 weeks) at birth were imaged a total of 53 times between birth and term. The median number of images per infant was two (range, 1 to 9). In infants of < 30 weeks GA, the germinal matrix was visualized at the margins of the lateral ventricles. It had a short T1 and short T2 and the bulk of it involuted at between 30 and 32 weeks GA. The white matter had a relatively homogeneous low signal except for bands of altered signal (probably originating from regions containing radial glia and migrating cells) which were most apparent anterolateral and posterolateral to the lateral ventricles. Myelination was seen in the posterior brainstem, cerebellum, and region of the ventrolateral nuclei of the thalamus. Infants had very little cortical folding at 25 weeks GA but this developed later in an orderly fashion. CONCLUSION: The neonatal MR system allowed extremely preterm infants to be studied safely with MR imaging. The images acquired demonstrated the germinal matrix, early myelination, and early cortical folding. Evolution of these features was demonstrated with serial studies.  相似文献   
98.
The presence and release of alpha 2-antiplasmin from human platelets   总被引:1,自引:0,他引:1  
Plow  EF; Collen  D 《Blood》1981,58(6):1069-1074
An antigen immunochemically indistinguishable from plasma alpha 2- antiplasmin, the primary plasmin inhibitor, was detected in human platelets. By radioimmunoassay, 33-114 ng alpha 2-antiplasmin antigen was quantitated in the detergent-soluble extract of 10(9) washed human platelets from 10 normal donors with a mean level of 62 +/- 24 ng/10(9) platelets. Plasma alpha 2-antiplasmin, either in the platelet suspending medium or on the surface of the platelets, could account for less than 8% of the antigen present in the platelet extracts. When stimulated with thrombin, the platelets released alpha 2-antiplasmin antigen without cell lysis, and greater than 85% of the alpha 2- antiplasmin antigen was released at a high thrombin dose. At a lower dose of thrombin, alpha 2-antiplasmin and platelet factor 4 were partially released without concomitant secretion of serotonin. No alpha 2-antiplasmin antigen was detected in extracts or red blood cells, polymorphonuclear leukocytes, and adherent and nonadherent mononuclear cells. Thus, the platelet is the only peripheral blood cell containing significant amounts of alpha 2-antiplasmin.  相似文献   
99.
100.
Felez  J; Chanquia  CJ; Fabregas  P; Plow  EF; Miles  LA 《Blood》1993,82(8):2433-2441
Cellular receptors for plasminogen and tissue plasminogen activator (t- PA) regulate plasminogen activation and cell-associated proteolytic activity. The characteristics of the interactions of both ligands with monocytes and monocytoid cell lines bear certain similarities, including affinity (kd approximately 1 mumol/L) capacity and susceptibility to carboxypeptidase treatment. Therefore, we have undertaken the present study to determine directly whether t-PA and plasminogen share common binding sites on cells. We found that recombinant human single-chain t-PA (rt-PA) could inhibit the binding of 125I-plasminogen to the cells and, conversely, plasminogen could inhibit 125I-rt-PA binding. This relationship was observed with 9 cell types, including both adherent cells and cells in suspension. In addition, under several conditions of cell treatment, plasminogen and t- PA receptor expression was modulated in parallel. Furthermore, molecules that have been implicated as candidate plasminogen receptors, gangliosides, and an alpha-enolase--related molecule, also interacted with t-PA. These results suggest that at least a component of the binding sites for plasminogen is shared with t-PA. Occupancy of these sites by either or both ligand(s) should result in arming the cells with the proteolytic activity of plasmin.  相似文献   
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