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排序方式: 共有617条查询结果,搜索用时 13 毫秒
81.
82.
Heini PF 《Therapeutische Umschau. Revue thérapeutique》2000,57(12):726-732
Spine injuries in a general practitioner's environment are mainly related to osteoporosis fractures in the elderly as well as cervical spine injuries in the elderly especially fractures of the odontoid process that need to be excluded if there is any suspicion. For osteoporotic spine fractures the invention of vertebroplasty offers a new treatment option and therefore patients should be transferred to a spine surgeon for further evaluation. The fracture of the odontoid process can end up in a non-union problem if not treated early; therefore this injury must be excluded in patients after sustaining any head contusion and complaints of neck pain afterwards. 相似文献
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84.
Localization of messenger RNA for Mr 72,000 and 92,000 type IV collagenases in human skin cancers by in situ hybridization. 总被引:20,自引:0,他引:20
We have examined the expression of 2 type IV collagen degrading enzymes (Mr 72,000 and 92,000 type IV collagenases) in human skin cancer by in situ hybridization. In all cases of infiltrating carcinomas of squamous cell (9 of 9) and basal cell (5 of 5) types, messenger RNA for the Mr 72,000 type IV collagenase was present in numerous fibroblasts. These were especially abundant in the stroma adjacent to the invasive tumor nodules. Malignant cells were negative for mRNA for the Mr 72,000 enzyme in all cases as were all other epithelial as well as endothelial cells. mRNA for the Mr 92,000 type IV collagenase was present in all 9 squamous cell and in 3 of the 5 basal cell carcinomas. In all these cases, a subpopulation of tissue macrophages was found to be positive, while malignant cells showed a signal for Mr 92,000 type IV collagenase in 6 of the squamous cell carcinomas but in none of the basal cell carcinomas. In all cases, the signal for this mRNA was confined to cells located at the tumoral/stromal interface or in the close vicinity of tumor nodules. No mRNA for any of the 2 collagenases was detected in 3 biopsies of normal skin. In vitro studies have indicated that collagenases are involved in the degradation of the extracellular matrix during cancer invasion. The present findings are consistent with such a role of the Mr 72,000 and 92,000 type IV collagenases in squamous and basal cell carcinomas in situ. The findings also demonstrate that degradative enzymes are not necessarily produced by the malignant cells themselves but may be generated by induction or recruitment of nonmalignant stromal cells. 相似文献
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86.
Paakkala A Mäkelä S Hurme M Partanen J Huhtala H Mustonen J 《Scandinavian journal of infectious diseases》2008,40(3):254-258
Different host genetic factors causes imbalance in the immune response. The purpose of this study was to establish whether pathological findings in chest radiography are related to the various host-related immunological factors in nephropathia epidemica (NE). Chest radiography findings, human leukocyte antigen (HLA) alleles B8, DR3, B27, genotypes of the genes of tumour necrosis factor alpha (TNFalpha), interleukin -1alpha (IL-1alpha), IL1beta and IL-1 receptor antagonist (IL1RA) were analysed in 114 patients with serologically confirmed acute NE. Both the presence and severity of abnormal NE-related chest radiography findings associated with the B8, DR3 and TNF2 alleles are known to form a frequent extended HLA haplotype in European populations. Pleural effusion showed the strongest association with these genetic factors. Pathological findings in chest radiography are related to host genetic factors in NE. Pleural effusion is a sign of increased capillary permeability, an important feature in NE. Host genetic factors may contribute to increased capillary permeability observed in NE patients. 相似文献
87.
Rapid downregulation of rat renal Na/Pi cotransporter in response to parathyroid hormone involves microtubule rearrangement 总被引:2,自引:0,他引:2 下载免费PDF全文
Marius L?tscher Yvonne Scarpetta Moshe Levi Nabil Halaihel Huamin Wang Hubert K. Zajicek Jürg Biber Heini Murer Brigitte Kaissling 《The Journal of clinical investigation》1999,104(4):483-494
Renal proximal tubule cells express in their apical brush border membrane (BBM) a Na/P(i) cotransporter type IIa that is rapidly downregulated in response to parathyroid hormone (PTH). We used the rat renal Na/P(i) cotransporter type IIa (NaPi-2) as an in vivo model to assess early cellular events in the rapid downregulation of this transporter. When rats were treated with PTH for 15 minutes, NaPi-2 abundance in the BBM was decreased. In parallel, transporter accumulated in intracellular vesicles. Concomitantly, microtubules (MTs) were found to form dense bundles of apical-to-basal orientation. After 60 minutes of PTH action, the cells were vastly depleted of NaPi-2, whereas their microtubular cytoskeleton had returned to its normal appearance. Prevention of MT rearrangement by taxol resulted in accumulation of NaPi-2 in the subapical cell portion after 15 minutes and a strong delay in depletion of intracellular transporter after 60 minutes of PTH action. Furthermore, the subapical accumulation of NaPi-2 was associated with the expansion of dense apical tubules of the subapical endocytic apparatus (SEA). Depolymerization of MTs by colchicine likewise caused a retardation of intracellular NaPi-2 depletion. These results suggest that NaPi-2 is downregulated in response to PTH through a rapid endocytic process in 2 separate steps: (a) internalization of the transporter into the SEA, and (b) its delivery to degradative organelles by a trafficking mechanism whose efficiency depends on a taxol-sensitive rearrangement of MTs. 相似文献
88.
Shoshanna Goldin So Yeon Joyce Kong Anna Tokar Heini Utunen Ngouille Ndiaye Jhilmil Bahl Ranil Appuhamy Ann Moen 《JMIR Public Health and Surveillance》2021,7(12)
BackgroundTo prepare key stakeholders for the global COVID-19 vaccination rollout, the World Health Organization and partners developed online vaccination training packages. The online course was launched in December 2020 on the OpenWHO learning platform. This paper presents the findings of an evaluation of this course.ObjectiveThe aim of this evaluation was to provide insights into user experiences and challenges, measure the impact of the course in terms of knowledge gained, and anticipate potential interest in future online vaccination courses.MethodsThe primary source of data was the anonymized information on course participants, enrollment, completion, and scores from the OpenWHO platform’s statistical data and metric reporting system. Data from the OpenWHO platform were analyzed from the opening of the courses in mid-December 2020 to mid-April 2021. In addition, a learner feedback survey was sent by email to all course participants to complete within a 3-week period (March 19 to April 9, 2021). The survey was designed to determine the perceived strengths and weaknesses of the training packages and to understand barriers to access.ResultsDuring the study period, 53,593 learners enrolled in the course. Of them, 30,034 (56.0%) completed the course, which is substantially higher than the industry benchmark of 5%-10% for a massive open online course (MOOC). Overall, learners averaged 76.5% on the prequiz compared to 85% on the postquiz, resulting in an increase in average score of 9%. A total of 2019 learners from the course participated in the survey. Nearly 98% (n=1647 fully agree, n=308 somewhat agree; N=1986 survey respondents excluding missing values) of respondents fully or somewhat agreed that they had more confidence in their ability to support COVID-19 vaccination following completion of this course.ConclusionsThe online vaccine training was well received by the target audience, with a measurable impact on knowledge gained. The key benefits of online training were the convenience, self-paced nature, access to downloadable material, and ability to replay material, as well as an increased ability to concentrate. Online training was identified as a timely, cost-effective way of delivering essential training to a large number of people to prepare for the COVID-19 vaccination rollout. 相似文献
89.
BACKGROUND: The objective of the study was to evaluate and compare the safety of levobupivacaine and racemic bupivacaine for paracervical block (PCB) in the first stage of labor after uncomplicated pregnancy. METHODS: Forty women in an open pilot study and 397 women in a double-blind randomized study received PCB for pain relief in the first stage of labor, either with 25 mg of levobupivacaine or with 25 mg of racemic bupivacaine. The incidence of cardiotocographic pathology was compared between the groups using Fisher's exact test. The 95% confidence intervals for the between-group difference were calculated by Newcombe's method. RESULTS: In the randomized double-blind study, the incidence of any pathological result in cardiotocography (CTG) was 10.4% in the levobupivacaine group and 12.8% in the racemic bupivacaine group. The incidence of fetal bradycardia in the groups was 2.6 and 3.8%, respectively. All the cardiotocographic changes were transient, and no operative intervention was indicated because of CTG. No difference in the analgesic effect between the drugs was found. Most of the parturients in the levobupivacaine group (97%) and in the racemic bupivacaine group (96%) had spontaneous vaginal delivery. Neonatal outcome was good in both groups. CONCLUSIONS: No difference in cardiotocographic pathology was found between PCB with levobupivacaine compared with PCB with racemic bupivacaine. The incidence of bradycardia was low. PCB was found to be a safe pain-relief method for low-risk parturients. 相似文献
90.
Reliability of pedicle screw assessment utilizing plain radiographs versus CT reconstruction 总被引:2,自引:0,他引:2
U. Berlemann P. Heini U. Müller C. Stoupis O. Schwarzenbach 《European spine journal》1997,6(6):406-410
The position of 119 pedicle screws was assessed on plain antero-posterior and lateral radiographs taken immediately post-operatively and at 3 months' follow-up. The readings of five independent observers were compared with the gold standard of CT reconstructions. The position of only 41 % of implants (range 14%–56%) was assessed correctly on the plain radiographs (47% on follow-up films). Two-thirds of CT-detectable perforations were missed. As shown with perforations of the anterior cortex, delectability increased significantly with magnitude of perforation. No specifically difficult anatomic level or direction of malplacement could be identified. Interobserver variation was considerable. Plain radiographs were shown to be of limited use in assessing the position of pedicle screws. 相似文献