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1.
M Heli?vaara O Impivaara K Sievers T Melkas P Knekt J Korpi A Aromaa 《Journal of epidemiology and community health》1987,41(3):251-258
The prevalence of lumbar disc syndrome (herniated disc or typical sciatica) and its consequences in terms of disability, handicap, and need for medical care were studied as part of the Mini-Finland Health Survey. A sample of 8000 persons representative of the Finnish population aged 30 or over was asked to come for examination, and 7217 (90%) participated. A diagnosis of lumbar disc syndrome based on medical history, symptoms, and standardised physical examination was made for 5.1% of the men and for 3.7% of the women. Half of these patients were assessed to be in need of medical care, over 80% of which was considered to be adequately met. One third of all patients with lumbar disc syndrome had been previously hospitalised for that syndrome, and one fifth of the patients had undergone lumbar surgery. At least slight disability was found in almost 60% of the patients, though severe functional limitations were rare. About 6% of the population's work disability was estimated to be attributable to lumbar disc syndrome. 相似文献
2.
Cholangiocarcinomas (CC) frequently demonstrate lymphatic spread. We investigated lymph node (LN) counts after resection of
extrahepatic CC and survival based on the SEER 1973–2004 database. Out of 20,068 CC patients, 1,518 individuals were selected
based on M0 stage and at least one LN examined. Primary cancer sites included gallbladder (29%), extrahepatic bile ducts (26%),
and intrapancreatic/ampullary bile ducts (45%); 42% of patients were LN-positive. The median number of LNs examined was four
(range 1–39). Median survival was 37 months for LN-negative and 16 months for LN-positive cancers. Multivariate prognostic
variables were the number of positive LNs, primary site, age (all at p < 0.0001), gender (p = 0.002), size (p = 0.005), T category (p = 0.009), and total LN count (or number of negative LNs obtained, p = 0.01). The impact of total LN counts was seen in LN-negative (median survival, 1 vs 10 or more LNs examined: 27 vs 51 months,
p = 0.002) and LN-positive disease (10 vs 22 months, p < 0.0001). Survival prediction of extrahepatic CCs is strongly influenced by total LN counts and numbers of negative LNs
obtained. Although the resulting incremental benefit is small, dissection and examination of 10 or more LNs should be considered
for curative intent resections. 相似文献
3.
Adverse mortality experience of a southwestern American Indian community: overall death rates and underlying causes of death in Pima Indians 总被引:1,自引:0,他引:1
As part of an ongoing epidemiologic study, the death rate and causes of death during 1975 through 1984 were determined in Pima Indians who resided in the Gila River Indian Community (GRIC) in 1965 and later. Death certificates were available for 677 of the 681 deaths. In 78% of the deaths, the underlying cause recorded on the death certificate agreed with the cause determined after review of all available relevant records. The age- and sex-adjusted average annual death rate for the GRIC population (1639/100,000) was 1.9 times (95% CI 1.7-2.0) the 1980 rate for the U.S. all races (878/100,000). In Pima males, whose death rate was substantially higher than that of Pima females, the age-adjusted death rate was 2.3 times that in U.S. males, all races. Moreover among males 25-34 years of age, the Pima death rate was 6.6 times that for the U.S. all races. Diseases of the heart and malignant neoplasms caused 59% of U.S. deaths in 1980, but only 19% of GRIC deaths. By contrast, the age- and sex-adjusted mortality rate in the GRIC Pima was 5.9 times the rate of the U.S. all races for accidents, 6.5 times for cirrhosis, 7.4 times for homicide, 4.3 times for suicide, and 11.9 times for diabetes. Tuberculosis and coccidioidomycosis were important causes of death in the Pima, for whom infectious diseases was the tenth leading cause of death. The findings indicate that programs to improve the adverse mortality experience of the GRIC population should emphasize factors related to fatal accidents, alcoholic cirrhosis, homicide, suicide, diabetes mellitus, and infectious diseases. Young Pimas, especially the males, should be the primary focus of such preventive efforts. These findings and recommendations probably apply to many Native American populations. 相似文献
4.
Wolfgang G Rehwald Michael Salerno Enn-Ling Chen Burkhard Sievers Raymond J Kim Robert M Judd 《Magnetic resonance in medicine》2007,58(1):82-91
To extend the signal longevity of magnetically excited spins in flowing fluids while in a state of global coherent free precession (GCFP), a refocusing radiofrequency (RF) pulse and bipolar gradient waveforms were combined with the GCFP sequence. The data demonstrate that RF refocusing in the presence of flowing blood is possible, but the improvement in signal amplitude depends on the static magnetic field homogeneity along the direction of motion and the displacement of the spins between the excitation and the RF refocusing pulse, as well as displacement during subsequent RF refocusing pulses. The least amount of phase dispersion and thus the longest lasting signal is obtained with the shortest echo spacing where only one line of data is recorded between two RF refocusing pulses. This approach was successfully used in a phantom and in vivo to image fast and slow blood flow. Depending on the experimental conditions, signal persistence is improved significantly compared to playing the same sequence without RF refocusing, but the improvement is limited by the product of blood flow velocity and the time between RF refocusing pulses. 相似文献
5.
H. H. Sievers 《Clinical research in cardiology》2000,89(8):730-733
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Antibody-dependent cellular cytotoxicity and neutralizing activity in sera of HIV-1-infected mothers and their children. 总被引:1,自引:1,他引:1
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K Broliden E Sievers P A Tovo V Moschese G Scarlatti P A Broliden C Fundaro P Rossi 《Clinical and experimental immunology》1993,93(1):56-64
The prognostic and protective role of antibodies mediating cellular cytotoxicity (ADCC) and neutralization was evaluated in sera of HIV-1-infected mothers and their consecutively followed children. The presence and titres of ADCC mediating and/or neutralizing antibodies in maternal sera did not predict HIV-1 infection in their respective children. No significant difference in the sera from the children was seen when comparing the presence of neutralizing antibodies between the uninfected and infected children. Stratification of the infected group according to clinical status revealed differences. Only one of 24 AIDS patients had a high neutralizing titre against IIIB. Four patients had a very low titre and the remaining had no detectable neutralizing antibodies at all. In contrast, 10/17 infected non-AIDS children had neutralizing antibodies. Similarly, no significant difference was seen when comparing the presence of ADCC-mediating antibodies between the uninfected and the infected group of children. However, a significantly higher frequency of ADCC was seen in the seropositive non-AIDS children compared with the AIDS children. This study clearly shows that the presence of antibodies mediating ADCC and neutralization in infected children, 0-2 years old, is associated with a better clinical status and delayed disease progression. 相似文献
9.
Jobst Sievers Christina von Knebel Doeberitz Fritz-Wilhelm Pehlemann Martin Berry 《Anatomy and embryology》1986,175(1):91-100
Summary We have investigated the influence of meningeal cells on the development of the cerebellum by destroying these cells with 6-hydroxydopamine in hamsters of different ages. The ensuing foliation and lamination disruption in the cerebellar vermis is attributed to a disintegration of the cerebellar surface and a disorganization of the glial scaf-fold of the cerebellar cortex due to a loss of meningeal-glial interaction in stabilizing the extracellular matrix at the glia limitans superficialis (v. Knebel Doeberitz et al. 1986, Neuroscience 17:409–426). The severity of these cerebellar defects is correlated with the ontogenetic stage at which meningeal cells are destroyed, being greatest after treatment at postnatal day 1 and decreasing thereafter until day 5 and beyond, when no abnormalities occur, although all meningeal cells are destroyed throughout. The absence of cerebellar defects after destruction of meningeal cells at day 5 or later is associated firstly with the end of the period of branching morphogenesis of the cerebellum when all folial primordia are established, and, secondly, with the maturation of the glia limitans superficialis. These findings indicate that meningeal cells stabilize the cerebellar surface and glial scaffold over a critical period that ends, when the pattern of cerebellar foliation is established, and when the glia limitans superficialis has reached a mature state. Beyond this stage glial end-feet alone are sufficient to maintain the epithelial integrity of the cerebellum. 相似文献
10.
Summary A bilaterally symmetrical cystic cavity is situated in the subependymal neuropil of the rostral rhombencephalon of the rat during the perinatal period of ontogeny. These cysts are formed by the confluence of enlarged extracellular spaces in this region between E18 and E20. The cysts are present for about 2 weeks but disappear on about P15 without trace. They have a maximal volume of about 0.004 to 0.006 mm3 on P2, with a rostrocaudal extension of about 200 m. Their shape is characterized by a medial convexity and a lateral concavity, and they have their maximal circumference at about the middle of the rostrocaudal axis. The caudal portion is juxtaposed to the subependyma, while the rostral part lies in the neuropil of the presumptive griseum centrale pontis. In the lumen and the wall of the cysts are found numerous macrophages, hlioblasts and some degenerating axons and dendrites.The significance of these cysts in the context of morphogenesis and the origin of the numerous macrophages within them are both unresolved. 相似文献