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排序方式: 共有4927条查询结果,搜索用时 46 毫秒
91.
S. Gundersen S. Kvinnsland S. Lundgren O. Klepp E. Lund O. Børmer H. Høst 《Breast cancer research and treatment》1990,17(1):45-50
Summary One-hundred and seventy patients with estrogen receptor positive (10 pmol/g protein) advanced breast cancer have been treated in a prospective randomized study either with continuous tamoxifen 30 mg × 1 daily (TAM), or with TAM 30 mg × 1 daily for 8 weeks alternating with medroxyprogesterone acetate 500 mg × 2 daily for 8 weeks (TAM/HD-MPA). The response rate was 62% in the group treated with cyclic TAM/HD-MPA versus 41% in the TAM alone group (p = 0.02). There was no significant difference in duration of remissions or survival. 相似文献
92.
A retrospective clinicopathological study of 37 patients with chordoma: a danish national series 总被引:1,自引:0,他引:1
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Purpose. There are, in general, few published series on chordoma. It is a rare disease and further data are still needed.Patients/methods. The data of 37 patients with chordoma were retrospectively analyzed. Treatment was surgical excision in 11, radical radiotherapy in 9 and a combination of the two in 16 cases. The male to female ratio was 2.7 : 1. Median age was 59 years (range 1-89 years).Results. The most common symptoms at diagnosis were pain (98%), neurological disturbances (42%) and incontinence (33%). The tumours were located in the sacro-coccygeal region in 68%, the spheno-occipital region in 16% and the vertebrae in 16% of the patients. Median tumour.size was 7 cm (range 1-30 cm). Local recurrence occurred in 21/36 treated cases and distant metastases developed in eight patients (23%). The median time to recurrence/progression after primary treatment was 2 years (range 1-10 years). The actuarial 5-year rates of overall, progression-free and symptom-free survival were 40%, 31% and 20%, respectively. The corresponding 10-year rates were 26%, 21% and 14%, respectively. At the time of analysis, seven patients were alive, six without evidence of disease. Four of the six patients without active disease were symptom free. A univariate analysis showed that age, sex, tumour size, histopathology, surgical safety margin, treatment modality and radiation dose did not significantly affect overall, progression-free or symptom-free survival. Only turnout site had a prognostic value with turnouts in the spheno-occipital region carrying the worst prognosis.Discussion. We conclude that effective treatment against chordomas is still lacking and a prospective multi-institutional registration study may provide more information on the optimal work-up and treatment of this rare disease. 相似文献
93.
The effects of caffeine on cytoplasmic Ca2+ oscillations induced by carbachol and guanosine 5-O-(3-thiotriphosphate) (GTP--S) were studied in individual mouse pancreatic ß-cells clamped at a hyperpolarized potential. Addition of 10 mM caffeine did not affect the cytoplasmic Ca2+ concentration ([Ca2+]1) in ß-cells exposed to 20 mM glucose and hyperpolarized with diazoxide. Under similar conditions 100 M carbachol induced a typical response with a marked [Ca2+]i peak followed by a lower sustained elevation. Irrespective of whether 10 mM caffeine was present, there were [Ca2+]i transients with frequencies of 1–5/min superimposed on the sustained phase in 50–60% of the cells. In previously non-exposed cells the introduction of 10 mM caffeine caused temporary lowering of the sustained phase with disappearance of the transients. Subsequent omission of caffeine in the continued presence of carbachol caused a marked [Ca2+]i peak followed by reappearance of the [Ca2+]i, transients. However, in cells oscillating in the presence of caffeine its omission caused disappearance of the transients. In this case reintroduction of caffeine restored the transients.In cells kept at –70 mV by a patch pipette containing 100 M GTP--S and 3 mM Mg-ATP there were [Ca2+]i transients with frequencies of 0.5–2.5/min. These transients were sufficiently pronounced to activate repetitively a K+ current. Addition of 10 mM caffeine caused disappearance of the [Ca2+]i transients or reduction of their amplitudes and frequencies.The results indicate that caffeine does not activate Ca2+-induced Ca2+ release in hyperpolarized ß-cells but inhibits the Ca2+-mobilizing effect of inositol 1,4,5-trisphosphate.
Correspondence to: E. Gylfe at the above address 相似文献
94.
95.
Barton JK Hammer DX Pfefer TJ Lund DJ Stuck BE Welch AJ 《Lasers in surgery and medicine》1999,24(3):236-243
BACKGROUND AND OBJECTIVE: Simultaneous irradiation and viewing of 10-120 microm cutaneous blood vessels were performed to investigate the effects of 2-micros 577-nm dye laser pulses. STUDY DESIGN/MATERIALS AND METHODS: A modified scanning laser confocal microscope recorded vessel response to different radiant exposures (J/cm2). Probit analysis determined the 50% probability ("threshold") radiant exposure necessary to cause embolized or partly occluding coagula, coagula causing complete blood flow stoppage, and hemorrhage. RESULTS: A statistically significant difference in the threshold radiant exposure existed for each damage category for blood vessels 10-30 microm in diameter, but not for larger vessels. For vessels over 60 microm, complete flow stoppage was unattainable; increasing laser pulse energy produced hemorrhage. In larger vessels, coagula often were attached to the superficial vessel wall while blood flowed underneath. Monte Carlo optical and finite difference thermal modeling confirmed experimental results. CONCLUSION: These results provide insight into the role of pulse duration and vessel diameter in the outcome of pulsed dye laser irradiation. 相似文献
96.
J. Ø. Odland V. P. Tchachtchine V. Bykov P. E. Fiskebeck E. Lund Y. Thomassen E. Nieboer 《International archives of occupational and environmental health》1999,72(3):151-160
Background: The feasibility study described herein was prompted by a report in 1992 of possible reproductive and developmental health
concerns among female workers in a Russian nickel refinery. Objective: The primary goal was to ascertain whether medical, statistical, and occupational data bases could be accessed for information
about the pregnancy histories, occupational histories, and life-style factors of the women affected. Methods: The project was facilitated by construction of a registry of all births in three towns with a nickel refinery and verification
of its contents against patients' records obtained from hospital delivery and gynecology departments and community polyclinics.
Municipal Registration Board, Regional Health Statistics Board, and nickel company records were also reviewed. Results: Reproductive/developmental outcome information and workplace histories were acceptable. Sample-size calculations indicated
that a cohort or cross-sectional study would be amenable and suitable for the detection of an excess risk for spontaneous
abortion with adequate statistical significance and power. Such investigations would need to be supplemented by workplace
environmental/biological monitoring assessments for evaluation of exposure to occupational hazardous factors and a worker's
questionnaire to obtain information about life-style factors. A case-control design is recommended for the study of congenital
defects. Conclusions: A well-designed, comprehensive epidemiology study is technically feasible because of the availability of a favorable pool
of study subjects, reproductive/developmental outcome data, information to control for major confounders, and suitable occupational
records.
Received: 13 July 1998 / Accepted: 7 February 1999 相似文献
97.
A model for the intracortical origin of orientation preference and tuning in macaque striate cortex.
We report results of numerical simulations for a model of generation of orientation selectivity in macaque striate cortex. In contrast to previous models, where the initial orientation bias is generated by convergent geniculate input to simple cells and subsequently sharpened by lateral circuits, our approach is based on anisotropic intracortical excitatory connections which provide both the initial orientation bias and its subsequent amplification. Our study shows that the emerging response properties are similar to the response properties that are observed experimentally, hence the hypothesis of an intracortical generation of orientation bias is a sensible alternative to the notion of an afferent bias by convergent geniculocortical projection patterns. In contrast to models based on an afferent orientation bias, however, the "intracortical hypothesis" predicts that orientation tuning gradually evolves from an initially nonoriented response and a complete loss of orientation tuning when the recurrent excitation is blocked, but new experiments must be designed to unambiguously decide between both hypotheses. 相似文献
98.
Dixon SR Ruygrok PN Agnew TM Lund M Aldersley PF Gibbs HC Whitlock RM Haydock DA Coverdale HA 《The New Zealand medical journal》1999,112(1099):417-420
AIMS: To determine the prevalence of cardiac allograft vasculopathy in heart transplant recipients at Green Lane Hospital and to examine potential risk factors for vasculopathy. METHODS: We retrospectively reviewed the coronary angiograms of all cardiac transplant recipients. Angiography was usually performed one, two and five years after operation. The diagnosis of allograft vasculopathy was made if there was any evidence of coronary artery disease. Patients' medical records were reviewed for potential risk factors. RESULTS: Ninety-one patients underwent cardiac transplantation between December 1987 and March 1998. One year survival was 87%. Angiographic evidence of coronary disease was present in 30 patients and in three patients coronary lesions were first identified at post mortem. Vasculopathy was present in 25%, 35% and 61% of patients at one two and five years following transplant. Donor-acquired lesions could not be excluded as few patients had immediate postoperative angiograms for comparison. Five late deaths have been due to vasculopathy. Recipient age, race, donor age and ischaemic time were similar for those with and without vasculopathy. Frequency or severity of acute rejection episodes, cytomegalovirus infection, lipid profiles, diabetes and hypertension were not significantly different in patients with vasculopathy. CONCLUSION: Cardiac allograft vasculopathy is a common finding after heart transplantation. No definite risk factors were identified in this patient group. 相似文献
99.
100.
Heiervang E Hugdahl K Steinmetz H Inge Smievoll A Stevenson J Lund A Ersland L Lundervold A 《Neuropsychologia》2000,38(13):211-1713
A reduction or reversal of the normal leftward asymmetry of the planum temporale (PT) has been claimed to be typical of dyslexia, although some recent studies have challenged this view. In a population-based study of 20 right-handed dyslexic boys and 20 matched controls, we have measured the PT and the adjacent planum parietale (PP) region in sagittal magnetic resonance images. For the PT, mean left and right areas and asymmetry coefficients were compared. Since a PP area often could not be identified in one or both hemispheres, a qualitative comparison was used for this region. The total planar area (sum of PT and PP) was also compared between the two groups. A dichotic listening (DL) test with consonant–vowel syllables was administered to assess functional asymmetry of language. The results showed a mean leftward PT asymmetry in both the dyslexic and the control group, with no significant difference for the degree of PT asymmetry. Planned comparisons revealed however, a trend towards smaller left PT in the dyslexic group. In control children, but not in the dyslexic children, a significant correlation between PT asymmetry and reading was observed. A mean leftward asymmetry was also found for the total planar area, with no difference between the groups for the degree of asymmetry. Significantly fewer dyslexic children than control children showed a rightward asymmetry for the PP region. Both groups showed a normal right ear advantage on the DL task, with no significant difference for DL asymmetry. No significant correlation was observed between PT asymmetry and DL asymmetry. The present population-based study adds to recent reports of normal PT asymmetry in dyslexia, but indicates that subtle morphological abnormalities in the left planar area may be present in this condition. 相似文献