| 1. |
- Tallini, G, et al.
(författare)
-
Correlation between clinicopathological features and karyotype in 100 cartilaginous and chordoid tumours. A report from the Chromosomes and Morphology (CHAMP) Collaborative Study Group
- 2002
-
Ingår i: Journal of Pathology. - : Wiley. - 0022-3417. ; 196:2, s. 194-203
-
Tidskriftsartikel (refereegranskat)abstract
- The evaluation of chondroid lesions requires full integration of clinical, radiographic, and pathological data; tumour typing is often a challenge for the diagnostic pathologist. Although a variety of chromosomal abnormalities have been documented in chondroid lesions, the potential usefulness of cytogenetic analysis remains unclear. This study has critically reviewed and analysed 117 karyotyped samples from 100 patients with cartilaginous and chordoid tumours. Cases were selected based on successful chromosomal analysis and adequacy of clinical, radiographic, and pathological information. To ensure objective evaluation, the cytogenetic results were correlated in a double-blind setting with consensus diagnoses independently determined on each case, after complete review of the histological, radiographic, and clinical findings. Karyotypic aberrations were identified in 41/92 cartilaginous tumours (5/11 osteochondromas, 2/3 chondromyxoid fibromas, 0/4 chondroblastomas, 11/29 chondromas, 0/3 chondroid tumours of undetermined malignant potential, 22/40 chondrosarcomas and 1/2 miscellaneous cartilaginous lesions) and 5/8 chordomas. Complex karyotypic changes were a feature of malignant tumours (chondrosarcoma and chordoma) and of chondrosarcoma among cartilaginous tumours, where they correlated with high tumour grade. Among primary well-differentiated cartilaginous lesions of bone, the finding of an abnormal karyotype was consistently associated with a grade 1 chondrosarcoma diagnosis. Among karyotypically abnormal cartilaginous tumours, loss of distal 8q was associated with osteochondroma, +5 with synovial chondroma/chondromatosis and parosteal or soft tissue chondroma, alterations of chromosome arm 6q with chondromyxoid fibroma, +7 with bone chondrosarcoma, and 17pl alterations with grade 3 chondrosarcoma. Alterations involving 12q13 characterized synovial chondroma/chondromatosis in the chondroma group and myxoid chondrosarcoma of bone in the chondrosarcoma group. In conclusion, cytogenetic abnormalities in chondroid lesions are common and are not randomly distributed. They are associated with malignancy/tumour grade as well as with specific diagnoses in many cases, and can therefore be of potential value for tumour typing.
|
|
| 2. |
|
|
| 3. |
- Fritzell, Peter, et al.
(författare)
-
Cost-effectiveness of lumbar fusion and nonsurgical treatment for chronic low back pain in the Swedish lumbar spine study : A multicenter, randomized, controlled trial from the Swedish Lumbar Spine Study Group
- 2004
-
Ingår i: Spine. - : Lippincott Williams & Wilkins. - 0362-2436 .- 1528-1159. ; 29:4, s. 421-434
-
Tidskriftsartikel (refereegranskat)abstract
- Study Design. A cost-effectiveness study was performed from the societal and health care perspectives. Objective. To evaluate the costs-effectiveness of lumbar fusion for chronic low back pain (CLBP) during a 2-year follow-up. Summary of Background Data. A full economic evaluation comparing costs related to treatment effects in patients with CLBP is lacking. Patients and Methods. A total of 284 of 294 patients with CLBP for at least 2 years were randomized to either lumbar fusion or a nonsurgical control group. Costs for the health care sector ( direct costs), and costs associated with production losses ( indirect costs) were calculated. Societal total costs were identified as the sum of direct and indirect costs. Treatment effects were measured using patient global assessment of improvement, back pain ( VAS), functional disability (Owestry), and return to work. Results. The societal total cost per patient ( standard deviations) in the surgical group was significantly higher than in the nonsurgical group: Swedish kroner (SEK) 704,000 ( 254,000) vs. SEK 636,000 ( 208,000). The cost per patient for the health care sector was significantly higher for the surgical group, SEK 123,000 ( 60,100) vs. 65,200 ( 38,400) for the control group. All treatment effects were significantly better after surgery. The incremental cost-effectiveness ratio ( ICER), illustrating the extra cost per extra effect unit gained by using fusion instead of nonsurgical treatment, were for improvement: SEK 2,600 ( 600 - 5,900), for back pain: SEK 5,200 ( 1,100 - 11,500), for Oswestry: SEK 11,300 ( 1,200 - 48,000), and for return to work: SEK 4,100 ( 100 21,400). Conclusion. For both the society and the health care sectors, the 2-year costs for lumbar fusion was significantly higher compared with nonsurgical treatment but all treatment effects were significantly in favor of surgery. The probability of lumbar fusion being cost-effective increased with the value put on extra effect units gained by using surgery.
|
|
| 4. |
|
|
| 5. |
- Järnerot, G, et al.
(författare)
-
Familial occurrence of microscopic colitis: a report on five families
- 2001
-
Ingår i: Scandinavian Journal of Gastroenterology. - : Informa UK Limited. - 1502-7708 .- 0036-5521. ; 36:9, s. 959-962
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The etiology and pathogenesis of microscopic colitis is unknown. Whether genetic predisposition is of importance, as in many other gastrointestinal diseases, is unknown. Familial occurrence of collagenous colitis has earlier been reported only in two families. METHODS: Familial occurrence of microscopic colitis was searched for in a Swedish national microscopic colitis register. RESULTS: Familial occurrence of microscopic colitis was identified in five families. In all families a sister-sister relationship was found. Two sisters with collagenous colitis had been living apart in different Nordic countries for many years before developing the disease. In one pair, the smoking sister had collagenous colitis and the never smoking sister had lymphocytic colitis. CONCLUSIONS: Considering the relative rarity of microscopic colitis, these findings indicate that a genetic predisposition may be of importance.
|
|
| 6. |
- Koul, A., et al.
(författare)
-
BRCA1 and BRCA2 mutations in ovarian cancer : Covariation with specific cytogenetic features
- 2000
-
Ingår i: International Journal of Gynecological Cancer. - : BMJ. - 1048-891X .- 1525-1438. ; 10:4, s. 289-295
-
Tidskriftsartikel (refereegranskat)abstract
- We analyzed 37 primary invasive carcinomas for BRCA1 and BRCA2 mutations by screening the entire coding regions of both genes. Seven predicted truncating mutations (four in BRCA1 and three in BRCA2) and one novel BRCA1 missense variant (S1542C) were identified (8/37, 22%). Two of the BRCA1 mutations were somatic changes, whereas the remaining three BRCA1 changes and all mutations of BRCA2 were found to be of germline origin. All eight BRCA-positive tumors were serous or seropapillary carcinomas (8/27 serous tumors, 30%), and all but one were poorly differentiated. The correlation between tumor karyotype and BRCA status showed that clonal chromosomal aberrations were present in all BRCA-positive tumors (8/8) compared with 20 of 29 BRCA-negative ones. The most consistently affected region in BRCA-positive tumors was the long arm of chromosome 6; alterations within this arm with a breakpoint in band 6q21 were seen in four of five BRCA1-positive and in two of three BRCA2-positive tumors, but only in four of 20 karyotypically abnormal tumors without BRCA mutations, suggesting that the genetic pathways of tumor progression differ in the two groups. The high frequency of germline BRCA mutations detected in this pilot study (16% of 37 invasive carcinomas) points to the need for more extended analyses of population-based series of patients to determine the true contribution of these predisposing genes to the overall incidence of ovarian cancer in this population.
|
|
| 7. |
- Rohner, M., et al.
(författare)
-
Sub-f(t) gain resonance of InP/InGaAs-HBTs
- 2002
-
Ingår i: IEEE Transactions on Electron Devices. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9383 .- 1557-9646. ; 49:2, s. 213-220
-
Tidskriftsartikel (refereegranskat)abstract
- Advanced npn-InP/InGaAs HBTs are often operated at high current levels for optimum high-speed performance. Because of velocity modulation effects, these transistors may operate in base-pushout although measurements of the cut-off frequency f(t) indicate the opposite. We show that the low mobility of the holes has a strong effect on the transistor operation in this regime, which is only revealed from a dynamic analysis: The unilateral power gain peaks far below f(t) followed by a -40 dB/dec roll-off. The effect was thoroughly analyzed and as a result, we present a simple equivalent circuit model that successfully describes transistors operating in pushout up to very high frequencies.
|
|
| 8. |
- Rohner, M., et al.
(författare)
-
Velocity-modulation and transit-time effects in InP/InGaAs HBTs
- 2001
-
Ingår i: IEEE Electron Device Letters. - : Institute of Electrical and Electronics Engineers (IEEE). - 0741-3106 .- 1558-0563. ; 22:9, s. 417-419
-
Tidskriftsartikel (refereegranskat)abstract
- The base-collector capacitance C-bc and the collector transit time delay tau
|
|
| 9. |
- Rohner, M., et al.
(författare)
-
Velocity modulation in III/V-HBTs
- 2003
-
Ingår i: IEEE Transactions on Electron Devices. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9383 .- 1557-9646. ; 50:5, s. 1205-1213
-
Tidskriftsartikel (refereegranskat)abstract
- Velocity modulation is shown to have a strong impact on the base/collector capacitance and the collector transit-time delay which dominate the high-speed performance of state-of-the-art HBTs. The authors present a theoretical analysis of the velocity modulation effects, which is the base of a method to assess their strength from measured S-parameters. Monte Carlo simulations are in good agreement with the measurements, providing strong support for the theory. As a consequence, the authors find that the carrier velocity is much lower than estimated from transit-time measurements when neglecting velocity modulation and that base-pushout occurs at much lower current levels than commonly expected.
|
|
| 10. |
- Schwarz, V., et al.
(författare)
-
56 Gbit/s analogue PLL for clock recovery
- 2001
-
Ingår i: Electronics Letters. - : Institution of Engineering and Technology (IET). - 0013-5194 .- 1350-911X. ; 37:22, s. 1336-1338
-
Tidskriftsartikel (refereegranskat)abstract
- A clock-recovery circuit is reported that employs a phase-locked. loop (PLL) at 56.88 Gbit/s. and is demonstrate by locking to a 28.44 GHz sinosoidal signal while two additional circuits with adapted on-chip passive components are locked to 29 and 39 Gbit/s pseudorandom bit sequences, To the knowledge of the authors, this is the First demonstration of an integrated PLL integrated circuit for clock recovery at a data rate well above 40 Gbit/s.
|
|
