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排序方式: 共有479条查询结果,搜索用时 15 毫秒
1.
Boom F. A. Van der Heijden Van Beek M. A. E. Paalman A. C. A. Stout-Zonneveld A. 《International journal of clinical pharmacy》1991,13(3):130-136
International Journal of Clinical Pharmacy - In order to calculate the minimum sterilization process conditions to obtain the generally accepted sterility level (less than 1·10?6... 相似文献
2.
J. H. Meier Dr. W. L. C. Rutten H. B. K. Boom 《Medical & biological engineering & computing》1995,33(3):409-417
Experimentally, during electrical nerve stimulation, the influence is examined of two intrafascicular anodes on the force
recruitment with one intrafascicular cathode. It is found that the anodes suppress recruitment and that this effect is more
pronounced when the distance of the anodes to the cathode is decreased, or when the anodal currents are increased. The measured
recruitment curve patterns can be qualitatively explained by a nerve stimulation model that calculates theoretical recruitment
curves for intrafascicular multi-electrode configurations. Discrepancies between the experimental and the theoretical recruitment
curves are seen, but these can be understood by taking into account a non-uniform fibre distribution. 相似文献
3.
Summary The cases of 80 patients with necrosis of the femoral head who underwent operative treatment in the period April 1980 to April 1988 are reported. Altogether, 102 operative procedures were carried out: 48 intertrochanteric osteotomies, 50 arthroplasties, 3 subchrondral bone graftings, and in one case drilling of the necrotic focus. Joint-preserving methods in advanced-stage disease seem to be of doubtful use when judged by clinical and socio-economic criteria over a mean follow-up time of 4.5 years. Since no conservative treatment exists, an improvement in therapeutic results can only be achieved by early diagnosis using magnetic resonance imaging and operating when the disease is still at an early stage. 相似文献
4.
Boom R Sol C Weel J Lettinga K Gerrits Y van Breda A Wertheim-Van Dillen P 《Journal of virological methods》2000,90(1):1-14
Epidemiological evidence linking the transmission of enteric viral disease to shellfish has been known for a long time. A variety of methods have been described for the detection of viral contaminants in shellfish using RT-PCR. However, these methods generally include numerous, often fastidious and time consuming steps for virus release from shellfish tissues and viral RNA isolation. A simplified procedure based on the enzymatic liquefaction of shellfish digestive tissues without any mechanical homogenisation step, followed by a simple clarification of the lysate using dichloromethane extraction, was developed. Viral RNA is isolated directly from the shellfish extract by a guanidium thiocyanate-silica extraction method, adapted for the use of a vacuum manifold system. Virus-specific RT-PCR assays were set up for detection of genomic sequences of the predominant viral pathogens, HAV, Astrovirus and Norwalk-like viruses (from genogoups I or II). The specificity of the amplicons is confirmed finally by hybridisation with DIG-labelled specific probes. The overall procedure applied to shellfish samples spiked with HAV particles allowed a detection of 20 pfu of HAV per g of hepatopancreas. In addition, up to 20 samples can be tested within 24 h. 相似文献
5.
BACKGROUND: There is no information about the desire and motivation for children among planned lesbian families. The overall aim of this research was to examine whether planned lesbian families differ from heterosexual families in desire and motivation to have a child. The reason for studying this is that desire and motivation to have children are characteristics that are supposed to effect parenting and the parent-child relationship. METHODS: A total of 100 lesbian two-mother families were compared with 100 heterosexual families. All data were collected by means of questionnaires. RESULTS: Lesbian parents and heterosexual parents rank their parenthood quite similarly; however, happiness is significantly more important for lesbian mothers than it is for heterosexual parents and identity development is less important for lesbian mothers than it is for heterosexual parents. Furthermore, compared with heterosexual parents, lesbian parents had spent more time thinking about their motives for having children, and their desire to have a child was stronger. CONCLUSIONS: Lesbian parents especially differ from heterosexual parents in that their desire to have a child is much stronger. The study's findings may be helpful for counsellors in their work to inform and assist lesbian couples in their decision to have a child. 相似文献
6.
OBJECT: The authors describe a computer-resident digital representation of a stereotactic atlas of the human brainstem, its semiautomated registration to sagittal fast low-angle shot three-dimensional (3-D) magnetic resonance (MR) imaging data sets in 27 healthy volunteers and 24 neurosurgical patients, and an analysis of the subsequent transforms needed to refine the initial registration. METHODS: Contour drawings from the atlas, which offer the 70th percentile of variation of anatomical structures, were interpolated into an isotropic 3-D representation. Initial atlas-to-patient registration was based on the fastigium/ventricular floor plane reference system. The quality of the fit was evaluated using superimposition of the atlas and MR images. If necessary, the atlas was tailored to the individual anatomy by using additional transforms. On average, the atlas had to be stretched by 2 to 6% in the three directions of space. Scale factors varied over a broad range from -8 to +19% and the benefit of visual interactive control of the atlas-to-patient registration was evident. Analysis of distances within the pons measured in the midsagittal MR imaging slices and the required scale factors revealed significant correlations that may be used to reduce the amount of user interaction in the coregistration substantially. In 70.6% of the cases, the atlas had to be shifted in a cranial direction along the brainstem axis (in 25.5% of cases 3-4 mm, in 45.1% of cases 1-2 mm). This was due to a more caudal position of the fastigium cerebelli on the MR images compared with the atlas. CONCLUSIONS: This observation, in conjunction with the variability of the height of the fourth ventricle in our MR imaging data (range 6.1-15.2 mm, mean 10.1 mm, standard deviation 1.8 mm) calls into question the role of the fastigium cerebelli as an anatomical landmark for localization within the brainstem. 相似文献
7.
Verkoelen CF van der Boom BG Kok DJ Houtsmuller AB Visser P Schröder FH Romijn JC 《Kidney international》1999,55(4):1426-1433
BACKGROUND: Adherence of crystals to the surface of renal tubule epithelial cells is considered an important step in the development of nephrolithiasis. Previously, we demonstrated that functional monolayers formed by the renal tubule cell line, Madin-Darby canine kidney (MDCK), acquire protection against the adherence of calcium oxalate monohydrate crystals. We now examined whether this property is cell type specific. The susceptibility of the cells to crystal binding was further studied under different culture conditions. METHODS: Cell-type specificity and the influence of the growth substrate was tested by comparing calcium oxalate monohydrate crystal binding to LLC-PK1 cells and to two MDCK strains cultured on either permeable or impermeable supports. These cell lines are representative for the renal proximal tubule (LLC-PK1) and distal tubule/collecting duct (MDCK) segments of the nephron, in which crystals are expected to be absent and present, respectively. RESULTS: Whereas relatively large amounts of crystals adhered to subconfluent MDCK cultures, the level of crystal binding to confluent monolayers was reduced for both MDCK strains. On permeable supports, MDCK cells not only obtained a higher level of morphological differentiation, but also acquired a higher degree of protection than on impermeable surfaces. Crystals avidly adhered to LLC-PK1 cells, irrespective of their developmental stage or growth substrate used. CONCLUSIONS: These results show that the prevention of crystal binding is cell type specific and expressed only by differentiated MDCK cells. The anti-adherence properties acquired by MDCK cells may mirror a specific functional characteristic of its in situ equivalent, the renal distal tubule/collecting ducts. 相似文献
8.
18F-2-fluoro-2-deoxy-d-glucose positron emission tomography in staging of locally advanced breast cancer. 总被引:4,自引:0,他引:4
Jacobus J M van der Hoeven Nanda C Krak Otto S Hoekstra Emile F I Comans Robert P A Boom Dick van Geldere Sybren Meijer Elsken van der Wall Jan Buter Herbert M Pinedo Gerrit J J Teule Adriaan A Lammertsma 《Journal of clinical oncology》2004,22(7):1253-1259
PURPOSE: To prospectively evaluate the effect of adding whole-body (18)F-2-fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) to conventional screening for distant metastases in patients with locally advanced breast cancer (LABC). PATIENTS AND METHODS: All women with LABC referred for participation in the LABC Spinoza trial were considered eligible for this study. Patients were included if chest x-ray, bone scan, liver ultrasound, or computed tomography scan performed by the referring physician failed to reveal distant metastases. They underwent whole-body FDG PET scanning before therapy. Patients with subsequently proven distant metastases were switched to alternative forms of chemotherapy, hormonal therapy, or both. RESULTS: Among the 48 patients evaluated with PET, 14 had abnormal FDG uptake, and metastases were suspected in 12. After simple clinical evaluation (plain x-ray, history), 10 sites that were suggestive of abnormality remained. Further work-up revealed that four sites were metastases. Proven false positivity occurred in one patient with sarcoidosis. In the other five patients, the reason for abnormal FDG uptake (liver, lung, bone) remained unclear, and patients were treated as planned. Eleven months later, distant metastases were found in one patient at sites unrelated to the previous FDG uptake. CONCLUSION: The addition of FDG PET to the standard work-up of patients with LABC may lead to the detection of unexpected distant metastases. This may contribute to a more realistic stratification between patients with true stage III breast cancer and those who are in fact suffering from stage IV disease. Abnormal PET findings should be confirmed to prevent patients from being denied appropriate treatment. 相似文献
9.
A. J. G. Swaak A. Hannema C. Vogelaar F. A. Boom L. van Es R. van Aalst L. W. Statius van Eps 《Rheumatology international》1982,2(4):161-166
Summary Measurement of complement components in serum may not accurately assess the degree of activation of the complement system. An alternative approach is the measurement of conversion products of the complement components. The relation between the presence of an increased concentration of C3-conversion products and the metabolism of C3 was investigated. In a group of patients, circulating immune complexes were also measured (Clq-binding test) to see whether the combination of those markers yielded information on the C3 metabolism. In this study it is shown that static measurements of serum C3 levels is of no value for the degree of complement activation. Measurement of C3-conversion products may indicate C3 hypercatabolism (in 8 of the 11 patients with C3-conversion products), but it does not imply depressed C3 synthesis. Detection of circulating immune complexes by the Clq-binding assay did not always indicate a C3 hypercatabolism. Of 12 SLE patients studied, in 9 of them, a C3 hypercatabolism was detected, and 5 of these patients were clinically characterized by the presence of minor disease symptoms. Overall, the results indicated that detection of circulating immune complexes and/or C3-conversion products could not be used as an absolute measure for insight into the C3 metabolism. 相似文献
10.
Arnoud A. Bruins Kay R. J. Kistemaker Annemieke Boom John H. G. M. Klaessens Rudolf M. Verdaasdonk Christa Boer 《Journal of clinical monitoring and computing》2018,32(2):335-341
Due to the high rates of epidural failure (3–32%), novel techniques are required to objectively assess the successfulness of an epidural block. In this study we therefore investigated whether thermographic temperature measurements have a higher predictive value for a successful epidural block when compared to the cold sensation test as gold standard. Epidural anesthesia was induced in 61 patients undergoing elective abdominal, thoracic or orthopedic surgery. A thermographic picture was recorded at 5, 10 and 15 min following epidural anesthesia induction. After 15 min a cold sensation test was performed. Epidural anesthesia is associated with a decrease in skin temperature. Thermography predicts a successful epidural block with a sensitivity of 54% and a PPV of 92% and a specificity of 67% and a NPV of 17%. The cold sensation test shows a higher sensitivity and PPV than thermography (97 and 93%), but a lower specificity and NPV than thermography (25 and 50%). Thermographic temperature measurements can be used as an additional and objective method for the assessment of the effectiveness of an epidural block next to the cold sensation test, but have a low sensitivity and negative predictive value. The local decrease in temperature as observed in our study during epidural anesthesia is mainly attributed to a core-to-peripheral redistribution of body heat and vasodilation. 相似文献