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21.
In the century or so since the birth of the research-based pharmaceutical industry, there has never been a more demanding time. The most pressing issue facing virtually all big pharmaceutical companies today is research and development productivity. Despite huge investments in research and development, the number of new medicines cleared for market has declined. On the other hand, there has never been a more exciting time to do healthcare research. New sciences and technologies are opening up radically new perspectives and opportunities for the future. Medical practice is undergoing a historic shift towards more personalized medicine. Over the next 10 years we can expect significant progress in the treatment of major diseases.  相似文献   
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Summary Sixteen patients with symptoms typical for Ockelbo disease (rash, arthralgia, fever) were enrolled in a 2 1/2 year study, during which clinical symptoms were recorded and ELISA was employed to study specific IgM, IgG and IgG subclass development. Initially, all patients presented with rash and arthralgia, and five patients still suffered from joint symptoms at the end of the study period. Ockelbo virus specific IgM was detected during the first week post onset in 6 patients and in 15 patients by day 14. One patient failed to develop specific IgM and was later diagnosed with a human parvovirus B 19 infection. All patients were IgM-negative 2 1/2 years post onset. Seroconversions or significant titer rises for specific total IgG were seen in 15 patients. IgG titers generally peaked within one year but in two patients maximum titers were seen 2 1/2 years post onset. Development of IgG1 followed that of total IgG, while IgG3, after an initial increase in all Ockelbo disease patients, remained at peak levels for one year in four patients, three of whom still had detectable IgG3 at the end of the study period. Ockelbo virus specific IgG2 or IgG4 was not detected in any of the patients.  相似文献   
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Sporadic amyotrophic lateral sclerosis is an idiopathic human degenerative disease of spinal cord and brain motor neurons. Prior studies demonstrated that most patients with amyotrophic lateral sclerosis posses immunoglobulins that bind to purified L-type voltage-gated calcium channels, that titers of anti–voltage-gated calcium channel antibodies correlate with disease progression rates, and that amyotrophic lateral sclerosis patient-derived antibodies (ALS IgG) produce electrophysiological changes in the function of voltage-gated calcium channels. Using Western transfer immunoblots and enzyme-linked immunosorbent assays, the calcium ionophore–forming α1 subunig of the voltage-gated calcium channel is now identified as the major voltage-gated calcium channel antigen to which ALS IgG binds. Additionally, the binding of an L-type voltage-gated calcium channel α1 subunit–directed monoclonal antibody, which itself mimics the effects of ALS IgG on skeletal muscle voltage-gated calcium channel currents, is selectively prevented by preaddition of ALS IgG. Voltage-gated calcium channel–binding IgG from patients with Lambert-Eaton myasthenic syndrome appears to be differentiated from ALS IgG by the reactivity of the former to both α1 and β subunits of the calcium channel. These assays provide further evidence linking amyotrophic lateral sclerosis to an autoimmune process, and suggest one means to differentiate immunoglobulins from patients with amyotrophic lateral sclerosis from those of patients with another autoimmune disease expressing calcium channel antibodies.  相似文献   
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The third variable (V3) loop of the human immunodeficiency virus type 1 (HIV-1) envelope protein is an important determinant for virus neutralization and cell tropism. V3 loop sequences from uncultured lymphocytes obtained in 1990 from 22 Ugandan HIV-1-infected patients could, with the exception of two patients' sequences, be divided into two groups (A and B) on the basis the V3 loop size and sequence. The V3 loop consensus sequences from both groups showed a high degree of homology to a U.S./European consensus, a characteristic also reflected by the results of peptide serology. In the case of group B the difference in sequence was only five amino acids. In contrast, the V3-flanking regions for both groups showed greater homology to an earlier (1986/1987) Ugandan consensus. The discovery of these two new Ugandan V3 loop genotypes, which are closely related to the U.S./European consensus, has implications for the understanding of the evolution of HIV-1 and for the future design of a vaccine for use in Africa.  相似文献   
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Surgical Principles The lateral approach is routinely combined with an osteotomy of the greater trochanter. We resect the newly formed callus located at the anterior, posterior and caudal aspect of the femoral neck distal to the epiphysis. No shortening of the femoral neck results from this procedure. One can safely avoid a vascular injury by performing a careful dissection, since the posteriorly reflected articular capsule containing the nutrient vessels to the head is detached from the femoral neck like a banana peel. The resection manoeuvre is performed next to the physeal plate of the slipped epiphysis. After callus resection, reduction of the femoral head by longitudinal traction and internal rotation of the limb is easy. The aim is complete correction of the slippage. When there is excess physeal cartilage, we resect it with a curette and then the head is fixed using 2 screws. Revised Version from: Operat. Orthop. Traumatol. 4 (1992), 77–85 (German Edition).  相似文献   
29.
We report experimental evidence for substantial individual differences in the susceptibility to simultaneous colour contrast. Interestingly, we found that not only the general amount of colour induction varies across observers, but also the general shape of the curves describing asymmetric matching data. A simple model based on von Kries adaptation and crispening describes the data rather well when we regard its free parameters as observer specific. We argue that the von Kries component reflects the action of a temporal adaptation mechanism, while the crispening component describes the action of the instantaneous, purely spatial mechanism most appropriately labeled simultaneous colour contrast. An interesting consequence of this view is that traditional ideas about the general characteristics of simultaneous contrast must be considered as misleading. According to Kirschmann’s 4th law, for instance, the simultaneous contrast effect should increase with increasing saturation of the surround, but crispening predicts the converse. Based on this reasoning, we offer a plausible explanation for the mixed evidence on the validity of Kirschmann’s 4th law. We also argue that simultaneous contrast, the crispening effect, Meyer’s effect and the gamut expansion effect are just different names for the same basic phenomenon.  相似文献   
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