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1.
2.
For more than two decades, the International Narcotic Control Board (INCB) has tried to stop harm reduction and its HIV prevention
programs. This posture is based on a fundamental misunderstanding of their responsibilities and of drug addiction itself –
i.e. as a public health and clinical care matter made criminal by decree. A recent focal point for the Board's action has
been rejecting the use of supervised injection facilities to reduce morbidity and mortality of drug injectors. They single
out individual countries and attempt to bully them into rejecting such programs under the banner of the United Nations (falsely)
and in the name of international treaties. Their unrelenting and unjustified badgering of signatories to the international
treaties that established the INCB is not only unjustified; it is an affront to one of the core purposes of the Board itself:
to ensure adequate medical supplies and safe use of controlled substances. The INCB's ill-conceived obsession with intravenousaddiction
as a crime flies in the face of the medical view and policies of the World Health Organization and the universally endorsed
principles of the General Assembly of the United Nations. 相似文献
3.
4.
Characteristics of chloride-dependent incorporation of glutamate into brain membranes argue against a receptor binding site 总被引:9,自引:0,他引:9
Although membrane sites from brain, labelled with [3H]glutamate (Glu) under sodium-free conditions, are thought to represent excitatory receptors, certain anomalous characteristics of the kinetics of apparent binding raised the question of whether transport might contribute to this process, prompting a closer examination of it. Hyperosmolar media and low incubation temperatures (4 degrees C) both led to decreases in the apparent specific binding of [3H]glutamate to membranes from the brain of the rat in the presence of chloride. Furthermore, only 15% of the [3H]glutamate, bound at 37 degrees C, was dissociable when the membranes were then cooled to 4 degrees C. The binding of [3H]glutamate was increased in the presence of certain dipeptides such as L-phenylalanyl-L-glutamate (Phe-Glu); and the binding augmented by the presence of Phe-Glu, was also sensitive to temperature and osmolarity of the incubation buffer. Sonication of membranes in 5 mM glutamate increased the apparent binding of [3H]glutamate and abolished the stimulatory effect of Phe-Glu. These findings are consistent with the hypothesis that chloride-dependent association of [3H]glutamate with membranes from brain reflects, in part, a sequestration process, which may be driven by glutamate exchange. 相似文献
5.
6.
Berbaum KS; el-Khoury GY; Franken EA Jr; Kathol M; Montgomery WJ; Hesson W 《Radiology》1988,168(2):507-511
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information. 相似文献
7.
Oral rehydration therapy (ORT) was hailed 10 years ago as potentially the most significant medical advance of the century. ORT is a simple and inexpensive means of treating diarrheal dehydration, which killed approximately 5 million children each year in the late 1970s. Today 25% of the world's children have access to ORT, and it is estimated that every year it saves 500,000 lives. Where ORT is not widely available, diarrheal dehydration remains the leading killer of children. It is still responsible for 25% of the 250,000 worldwide child deaths each week. Because there have been problems with acceptance of the ORT formula of salt, sugar, and water, researchers have been experimenting with cereal-based oral rehydration formulas that are much like traditional home remedies for diarrhea. In addition to relieving dehydration, these cereal-based formulas lessen severity and duration of diarrheal illness. Critics, however, claim that they fail to provide a child with sufficient calories, and call for a combination of ORT with early feeding--4-8 hours after completion of rehydration. Even with growing evidence of the benefits of early feeding, the practice of withholding food from children with diarrhea persists in the developing world and in the U.S. Problems in developing countries are greater, but each year 14 of every 1,000 American infants are hospitalized because of acute diarrhea. The major hurdle that ORT faces in the U.S. is that it is a simple form of therapy attempting to displace a higher technology. As long the U.S. health care system serves as a model for developing countries, distrust of ORT by American doctors will hamper efforts to spread ORT in the developing world. 相似文献
8.
J-L Stievenart EA Cabanis P Menard J Knoplioch A Lopez J Tamraz M-T Iba-Zizen B Philippe G Prevost J-C Bertrand 《Surgical and radiologic anatomy : SRA》1993,15(1):47-54
Summary In view of the variety of 3D representation techniques, a clinical study was carried out in order to evaluate their respective usefulness. It appears that a single technique cannot be claimed to be valid for all clinical situations and that a combination of representations brings more relevant information. Among the different techniques a clear delineation must be established between those which allow the accurate definition of landmarks (multiplanar reformation, surface representation), and those which do not (integral shading, reconstructed radiology). The main point is the possibility to recognize anatomical landmarks on these latter modes and to choose oblique cut planes in relation to them. Visualization quality is strongly dependent upon the acquisition protocol which must provide a spatial resolution as isotropic as possible.
Une revue de différents modes de visualisation en haute résolution d'un objet volumique avec des applications
Résumé Face à la variété des techniques de représentation 3D une étude clinique a été conduite pour évaluer leurs utilités respectives. Il apparait qu'une technique unique ne peut pas convenir à toutes les situations cliniques et qu'une combinaison de différents modes de présentation apporte une information plus pertinente. Parmi les différentes techniques une distinction claire doit être établie entre celles qui autorisent la prise de repères précis (reformatage multiplanaire, représentation de surface), et celles qui ne le permettent pas (ombrage intégral, radiologie reconstruite). Le point principal est la possibilité de reconnaître des repères anatomiques sur ces derniers modes et de choisir des plans de coupe en relation avec eux. La qualité de la visualisation dépend étroitement du protocole d'acquisition qui doit fournir une résolution aussi isotrope que possible.相似文献
9.
Igarashi S; Takiyama Y; Cancel G; Rogaeva EA; Sasaki H; Wakisaka A; Zhou YX; Takano H; Endo K; Sanpei K; Oyake M; Tanaka H; Stevanin G; Abbas N; Durr A; Rogaev EI; Sherrington R; Tsuda T; Ikeda M; Cassa E; Nishizawa M; Benomar A; Julien J; Weissenbach J; Tsuji S 《Human molecular genetics》1996,5(7):923-932
Machado-Joseph disease (MJD) is an autosomal dominant neurodegenerative
disorder caused by unstable expansion of a CAG repeat in the MJD1 gene at
14q32.1. To identify elements affecting the intergenerational instability
of the CAG repeat, we investigated whether the CGG/GGG polymorphism at the
3' end of the CAG repeat affects intergenerational instability of the CAG
repeat. The [expanded (CAG)n-CGG]/[normal (CAG)n- GGG] haplotypes were
found to result in significantly greater instability of the CAG repeat
compared to the [expanded (CAG)n- CGG]/[normal (CAG)n-CGG] or [expanded
(CAG)nGGG]/[normal (CAG)n-GGG] haplotypes. Multiple stepwise logistic
regression analysis revealed that the relative risk for a large
intergenerational change in the number of CAG repeat units (< -2 or >
2) is 7.7-fold (95% CI: 2.5-23.9) higher in the case of paternal
transmission than in that of maternal transmission and 7.4-fold (95% CI:
2.4-23.3) higher in the case of transmission from a parent with the
[expanded (CAG)n-CGG]/[normal (CAG)n-GGG] haplotypes than in that of
transmission from a parent with the [expanded (CAG)n-CGG]/[normal
(CAG)n-CGG] or [expanded (CAG)n- GGG]/[normal (CAG)n-GGG] haplotypes. The
combination of paternal transmission and the [expanded (CAG)n-CGG]/[normal
(CAG)n-GGG] haplotypes resulted in a 75.2-fold (95% CI: 9.0-625.0) increase
in the relative risk compared with that of maternal transmission and the
[expanded (CAG)n-CGG]/[normal (CAG)n-CGG] or [expanded (CAG)n- GGG]/[normal
(CAG)n-GGG] haplotypes. The results suggest that an inter- allelic
interaction is involved in the intergenerational instability of the
expanded CAG repeat.
相似文献
10.
Functional consequences of ROMK mutants linked to antenatal Bartter's syndrome and implications for treatment 总被引:4,自引:0,他引:4
The antenatal variant of Bartter's syndrome is an autosomal recessive
kidney disease characterized by polyhydramnios, premature delivery,
hypokalemic alkalosis and hypercalciuria. It is genetically heterogeneous,
having been linked recently to mutations in an ATP- sensitive, renal outer
medullary K+channel, ROMK, and earlier to mutations in the Na-K-2Cl
co-transporter, NKCC2. We characterized four of the mutations reported in
three heterozygous ROMK variants of antenatal Bartter's and found that each
expressed a distinct phenotype in Sf9 cells. One mutation expressed normal
function and appears to be an allelic polymorphism. The other three
mutations produced channels with significantly reduced K+fluxes. However,
the mechanisms in each case were different and reflected abnormalities in
phosphorylation, proteolytic processing or protein trafficking. The
different mechanisms may be important in the design of appropriate therapy
for patients with this disease.
相似文献