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101.
G Granstr?m C Jacobsson B C Magnusson 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》1991,25(2):133-141
Craniofacial malformations were induced in 256 embryos from 32 pregnant rats by a single intraperitoneal injection of 10 mg/kg etretinate at 8.5 days gestation. The litters developed several malformations including microtia, low set and dorsally placed outer ears, defective middle ear ossicles, short cochleas, defectively differentiated Meckel's cartilages, micrognathia, rudimentary malar bones, lateral facial clefts, fistulas, and skin tags, all of which tissues are derivatives of the first and second branchial arches. The teratogenically induced syndrome shows similarities to the mandibulofacial dysostosis syndrome in man. The defects were accompanied by a change in the histochemical differentiation and location of various enzymes in the craniofacial tissues. 相似文献
102.
Occult cerebral vascular malformations: high-field MR imaging 总被引:4,自引:0,他引:4
Gomori JM; Grossman RI; Goldberg HI; Hackney DB; Zimmerman RA; Bilaniuk LT 《Radiology》1986,158(3):707-713
Occult cerebral vascular malformations (OCVMs) have characteristic appearances on high-field magnetic resonance (MR) images. These consist of circumscribed regions of low intensity, most prominent on T2-weighted images and representing hemosiderin deposits. Interspersed within most of these lesions are multiple areas of various signal intensity patterns, which correspond to hematomas in different stages of evolution and to fibrous regions containing calcium as well as hemosiderin. Forty-six lesions were found in 19 patients (34 supratentorial and 12 infratentorial). The supratentorial lesions tended to be subcortical or periventricular. Computed tomography depicted 24 of the 46 lesions demonstrated by high-field MR. Comparison of images obtained with both low-field MR (0.12 T and 0.35 T) and high-field MR (1.5 T) revealed that high-field MR imaging was superior in depicting OCVMs. High-field MR appears to be both sensitive and specific for OCVMs and may obviate the need for possible biopsy of these lesions. 相似文献
103.
This is a presentation of some preliminary data from SPCG-I, a multicenter study started in 1984 by the Scandinavian Prostatic Cancer Group. It is a randomized double-blind study comparing estramustine phosphate and diethylstilbestrol in the primary treatment of 195 patients with T1-4, NX, M1, G2-3 prostatic cancer. The code is not yet broken. This presentation describes the impact of the pretreatment parameters performance status, pain, tumor burden, grade and DNA-ploidy of the prostate tumor, on time to progression and overall survival. DNA studies have so far only been completed in 66 of the 195 patients. For the whole group of 195 patients, pain (p less than 0.004) and tumor grade (p less than 0.02) had the most significant impact on time to progression, and performance status (p less than 0.01) and grade (p less than 0.03) on overall survival. In the small group of 66 patients where the DNA pattern of the primary tumor was evaluated, no parameter had any significant correlation to time to progression and overall survival. This study is still continuing. 相似文献
104.
Donor screening for antibody to hepatitis B core antigen and hepatitis B virus infection in transfusion recipients 总被引:10,自引:0,他引:10
JW Mosley ; CE Stevens ; RD Aach ; FB Hollinger ; LT Mimms ; LR Solomon ; LH Barbosa ; GJ Nemo 《Transfusion》1995,35(1):5-12
BACKGROUND: Testing for antibody to hepatitis B core antigen (anti-HBc) as a surrogate for hepatitis C viremia is no longer needed for blood donor screening. Currently, the important question is how much its use supplements hepatitis B surface antigen (HBsAg) donor screening in preventing transfusion-transmitted hepatitis B virus (HBV) infection. STUDY DESIGN AND METHODS: In a study conducted in the 1970s, 64 blood donors were associated with 15 cases of HBV (1.0%) in 1533 transfusion recipients. Sera from 61 donors at donation and 29 follow-up visits were available for present-day assays for HBsAg, HBV DNA, anti-HBc, and antibody to HBsAg (anti-HBs). RESULTS: HBsAg was found in four previously negative blood donors; HBV DNA was limited to three of these four. Anti-HBc was detected in six HBsAg-negative donors. Two other donors were negative in all assays at donation, but positive for anti- HBc and anti-HBs 2 to 4 months later. The remaining donors were negative for all HBV markers, which left five recipient cases unexplained. No HBV transmission was observed when anti-HBs sample-to- negative control values were > or = 10. CONCLUSION: Some 33 to 50 percent of cases of hepatitis B that could be transmitted by transfusion of blood from HBsAg-negative donors are prevented by anti- HBc screening. Anti-HBc-positive donors unequivocally positive for anti- HBs should be considered noninfectious for HBV and should be allowed to donate. Anti-HBc screening of paid plasmapheresis donors, supplemented by anti-HBs testing, would reduce the amount of HBV to be processed by virus inactivation and increase the content of anti-HBs in plasma pools. 相似文献
105.
B Forsberg ; S Jacobsson ; D Stockelberg ; J Kutti ; L Rydberg ; H Wadenvik 《Transfusion》1995,35(3):241-246
BACKGROUND: There is an increasing interest in the development of rapid and reliable techniques for platelet alloantigen typing. STUDY DESIGN AND METHODS: By use of standardized flow cytometry and a specific human alloantiserum, 236 Swedish blood donors were immunophenotyped for the platelet-specific alloantigen, PlA1 (HPA-1a). RESULTS: Ten individuals (4.2%) had low fluorescence intensities and were considered PlA1- negative (HPA-1a-negative); all of them also demonstrated a PlA2/PlA2 (HPA-1b/1b) genotype in a polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) assay of the underlying DNA polymorphism. The remaining population had clear positive fluorescence and was regarded as PlA1-positive (HPA-1a-positive). The fluorescence distribution histogram among PlA1-positive (HPA-1a-positive) individuals was dome-shaped, and those individuals who were homozygous for PlA1 (HPA-1a) could not be distinguished from those who were heterozygous. This finding was further substantiated by PCR-RFLP analysis of the PlA1/PlA2 (HPA-1a/1b) genotype; a heterozygous genotype was found among those having a medium fluorescence intensity as well as among those having a strong fluorescence intensity. CONCLUSION: Flow cytometry is a valuable tool for large-scale detection of PlA1 (HPA- 1a). However, flow cytometry based on only one antiserum cannot distinguish between homozygous and heterozygous carriers of PlA1 (HPA- 1a). For zygosity testing and when platelets are difficult to obtain, the PCR-RFLP technique is the assay of choice. 相似文献
106.
OBJECTIVE: To investigate the mechanisms behind the increase of chronic tension-type headache during head-down tilt. BACKGROUND: The pathophysiology of chronic tension-type headache is unknown. DESIGN AND METHODS: Ten patients suffering from chronic tension-type headache and 10 age- and sex-matched controls were studied with respect to pain intensity and alterations in cranial blood volume using planar scintigraphy and radiolabeled autologous erythrocytes before, during, and after head-down tilt, a procedure known to increase chronic tension-type headache. RESULTS: Four of 8 patients with chronic tension-type headache studied had increased cerebrospinal fluid pressure. During head-down tilt, the pain increased significantly in the group with chronic tension-type headache (P <.001) while the procedure did not cause headache in the controls. Blood volume significantly increased extracranially and decreased intracranially in both groups during head-down tilt. The extracranial nasal blood volume was significantly related to the pain experienced by the patients with chronic tension-type headache before and during head-down tilt. CONCLUSIONS: Although the changes in blood volume and, presumably, the increase of intracranial pressure were similar in the patients with chronic tension-type headache and the controls, only the patients experienced pain and pain increase during head-down tilt. This indicates that the pre-head-down tilt conditions must be different in the 2 groups and should be related to increased cerebrospinal fluid pressure/intracranial venous pressure in patients with chronic tension-type headache compared with controls. A difference in central mechanisms may, however, also be of importance for the difference in headache provocation in the 2 groups during head-down tilt. 相似文献
107.
108.
109.
PURPOSE OF REVIEW: The purpose of this review is to present an update on the evidence-based effects of exercise in systemic lupus erythematosus and in primary Sj?gren's syndrome. RECENT FINDINGS: Physical capacity is reduced in both systemic lupus erythematosus and primary Sj?gren's syndrome and fatigue is a dominating and disabling symptom in both conditions. The documentation on the effect of exercise on the rehabilitation of patients with systemic lupus erythematosus and primary Sj?gren's syndrome is sparse; the studies are few and the sample sizes often small. The available studies indicate that patients with systemic lupus erythematosus of mild to moderate disease activity as well as patients with primary Sj?gren's syndrome benefit from exercise of moderate to high intensity. Positive effects can be expected with regard to aerobic capacity, fatigue, physical function and depression. SUMMARY: There is reason to believe that exercise should be included in the rehabilitation of patients with mild to moderate systemic lupus erythematosus and patients with primary Sj?gren's syndrome. Further research is needed and should aim to evaluate the effect of exercise on groups with varying degree of disease severity and to document the long-term impact on the disease. 相似文献
110.