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This article has made a number of points that assert what is today a minority position within the fields of MPD/DID and BPD. We hope our views will stimulate attempts by others to rethink their positions and test our assertions, so that issues surrounding these two disorders can be sharpened. For the sake of the clarity of future work, we summarize in outline form the essence of our viewpoint. 1. BPD and MPD/DID have similar appearing symptoms, such as identity problems, unstable affect modulation, self-destructive behaviors, chaotic impulse control, and troubled interpersonal relationships, but they have decisive differences in underlying dynamics, process, and structure. 2. DSM tends to blur these two disorders by its emphasis on phenomenology over inner structure, thus fostering misleading conclusions when DSM criteria are used to test for comorbidity or overlap between BPD and MPD/DID. 3. BPD and MPD/DID are both described dynamically as using the defense of splitting, but we contend that the splitting in each disorder is fundamentally different from the splitting in the other. BPD uses a polarization form of splitting, whereas MPD/DID uses ego splitting or identity division. 4. Both disorders partake in the process of dissociation, but the quality of dissociation in BPD is a "low-tech" spaced out type, whereas that of MPD/DID is a "high-tech" waking dream. 5. BPD structure is also "low tech," with polarization of self, object, and relationship. MPD/DID structure is "high tech," with heavily symbolic, highly nuanced variations of self, object, and relationship. 6. Although both conditions have etiologic elements of trauma, BPD has a larger degree of developmental deficiency, with a failure to complete the task of entering a repression hierarchy of defenses. MPD/DID, by use of primary process-linked symbolic dissociation, is able to continue development to the repression hierarchy, although at a profound cost of simultaneous suspension of reality testing. BPD patients suffer from the rigid use of too few defenses; MPD/DID patients suffer from the obsolete use of too many defenses. 7. BPD patients grow up in homes in which overtly expressed aggression is more tolerated, or at least more openly experienced. MPD/DID patients grow up in homes in which the fact of aggression is kept a secret. This has consequences for the formation of psychic structure in each disorder.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
3.
After being poisoned by eating the mushroom species Cortinarius speciosissimus, a twin developed interstitial nephritis with acute renal failure. He received a renal transplant from his living twin brother, who was presumed dizygotic on phenotypic grounds. Fifteen years later, the twins were zygosity tested by DNA "fingerprint analysis" and found to be monozygotic, despite important phenotypic discordances. The recipient has discontinued immunosuppression therapy and remains well after 9 months. We suggest that, for medical and other reasons, zygosity should be determined at birth on all like-sexed twins.  相似文献   
4.
Virtual queue-based active queue management schemes have been proposed to provide low-loss, low-delay service in the Internet. In an earlier work, we had proposed a particular scheme called the adaptive virtual queue (AVQ) algorithm where the capacity of the virtual queue is adapted to the traffic conditions to achieve a desired level of utilization in the network. Here, we study the choice of the parameters of the congestion-controllers at the sources and the AVQ scheme at the links that is required to ensure stability. In particular, we consider a system in which users with diverse round-trip delays and fairness requirements access a general topology network. For this system, we show that, by choosing the speed of adaptation at the sources and the links appropriately, one can guarantee the stability of the network.  相似文献   
5.
Stable scheduling policies for fading wireless channels   总被引:1,自引:0,他引:1  
We study the problem of stable scheduling for a class of wireless networks. The goal is to stabilize the queues holding information to be transmitted over a fading channel. Few assumptions are made on the arrival process statistics other than the assumption that their mean values lie within the capacity region and that they satisfy a version of the law of large numbers. We prove that, for any mean arrival rate that lies in the capacity region, the queues will be stable under our policy. Moreover, we show that it is easy to incorporate imperfect queue length information and other approximations that can simplify the implementation of our policy.  相似文献   
6.
There has been much interest in admission control schemes that place the burden of admission control decisions on the end users. In these schemes, referred to as Endpoint Admission Control, the decision to join the network is taken by the user, based on the probing of the network using probe packets. Depending on the level of congestion, routers mark the probe packets and thus inform the user of the state of the network. In this paper, we analyze three mechanisms for providing Endpoint Admission Control: virtual-queue marking, random-early marking and tail drop. For each scheme, we analyze the probing duration necessary to guarantee the required QoS and achieve high link utilization. Our main conclusion is that very few probe packets have to be sent when early marking is used, whereas tail drop requires a large number of probe packets.  相似文献   
7.
In order to provide an adequate quality of service to large-bandwidth calls, such as video conference calls, service providers of integrated services networks may want to allow some customers to book their calls ahead, i.e., make advance reservations. We propose a scheme for sharing resources among book-ahead (BA) calls (that announce their call holding times as well as their call initiation times upon arrival) and non-BA calls (that do not announce their holding times). It is possible to share resources without allowing any calls in progress to be interrupted, but in order to achieve a more efficient use of resources, we think that it may be desirable to occasionally allow a call in progress to be interrupted. (In practice, it may be possible to substitute service degradation, such as bit dropping or coarser encoding of video, for interruption.) Thus, we propose an admission control algorithm in which a call is admitted if an approximate interrupt probability (computed in real time) is below a threshold. Simulation experiments show that the proposed admission control algorithm can be better (i.e., yield higher total utilization or higher revenue) than alternative schemes that do not allow interruption, such as a strict partitioning of resources  相似文献   
8.
An equimolar mixture of phosphatidylserine and (dioleoyl) phosphatidyl-ethanolamine could substitute for brain cephalin preparations in the single stage prothrombin assay. However, no clot promoting activity was observed on the addition of any of the individual long chain fatty acid-containing phospholipids. Short chain fatty acid-containing phospholipids, such as diheptanoylphosphatidylcholine, diheptanoylphosphatidylethanolamine, diheptanoylphosphatidic acid, and dihexanoylphosphatidylcholine, or dihexanoylphosphatidylethanolamine were inhibitory under all conditions studied. Similar effects of these two general classes of phospholipids were observed in a two-stage thrombin generation system, in which a mixture of bovine Factor Xa, Factor Va, and Ca2+ were interacted with prothrombin. In the presence of 25 mM Ca2+, dioleoylphosphatidic acid or brain phosphatidylserine alone, and with other long chain phospholipids, formed complexes with bovine plasma prothrombin. On the other hand, dioleoyl-, diheptanoyl- or dihexanoylphosphatidylcholine under comparable conditions showed no binding to prothrombin. There appeared to be a small degree of binding of diheptanoylphosphatidic acid to prothrombin, but it was insufficient to cause any significant change in apparent molecular weight of prothrombin. A mixture of prothrombin, Factor V, diheptanoylphosphatidic acid/diheptanoylphosphatidylcholine and Ca2+ eluted in the void volume of Sephadex G-200, but showed a much reduced coagulant activity. Though a net negative charge on the phospholipid surface is required for phospholipid-protein interactions, this does not necessarily promote coagulant activity. Bile acids and bile salts, such as cholic acid, deoxycholic acid, taurocholic acid, glycocholic acid, lithocholic acid and dehydrocholic acid, exerted varying levels of stimulation on the prothrombin assay and thrombin generation system, but were not as effective as the phospholipids. Interestingly, no interaction of these bile acids or salts with prothrombin was noted in the presence of Ca2+. The results of these experiments suggest that negatively charged micelles per se are not sufficient for binding alone and that other chemical and physical characteristics of phospholipids are of prime importance.  相似文献   
9.
Nonsuppressible insulin-like activity, provided by three sources, was evaluated for its effect on the proteolytic degradation of insulin utilizing insulin protease obtained from rat liver homogenate as well as liver cell membranes. All three preparations of nonsuppressible insulin-like activity were found to be competitive inhibitors of insulin degradation. In addition human plasma was fractionated yielding an acetone precipitate which was found to have nonsuppressible insulin-like activity and to be a competitive inhibitor of insulin protease.  相似文献   
10.
Conformational properties of (2'-5') and (3'-5') CpC have been determined by proton magnetic resonance spectroscopy at 220 MHz. The ribose ring structures are predominantly 3E with the exception of the ring from the 2'-phosphate fragment of C(2'-5')pC which exhibits an 2E pucker. Bases are oriented anti with respect to the ribose and the conformations about C4'-C5', C5'-O5', C3'-O3' (C2'-O2') are gg, g'g', and g+ in equilibrium g-, respectively. The dimers exist as mixtures of stacked (g+g+ and g-g- about the P-O(C) bonds) and unstacked species at 20 degrees C. Stacking is estimated to be 35% in both dimers.  相似文献   
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