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951.
Rheumatoid arthritis pannus: true or false?   总被引:1,自引:0,他引:1  
  相似文献   
952.
953.
In leukemia and preleukemic disorders the progeny of a single cell proliferate and ultimately come to occupy the hemopoietic system. In the process normal stem cells are suppressed and in time may become extinct. This implies that neoplastic clones have a biological advantage. In this paper evidence is presented that the cloning of granulocytic colony forming cells in the clonal hemopathies is influenced by cell products that regulate cloning of normal colony forming cells. We have attempted to develop an approach to the study of clone-clone interactions in order to determine at what level(s) the battle between clones is fought. Future studies on relative responsiveness might help in understanding the mechanisms by which normal hemopoiesis is suppressed during the evolution of leukemia and re-established during remission induction.  相似文献   
954.
The criminal records of alleged offenders diverted from the normal process of prosecution were examined on average 31 months after assessment at a forensic clinic. Twenty-five per cent of those assessed reoffended. The apparent effect of treatment became statistically non-significant when other variables were controlled. It is argued that the case against the effectiveness of treatment remains 'non-proven' and that psychological benefits may accrue even in the absence of an effect on reconviction rate.  相似文献   
955.
Eleven of 32 newly diagnosed untreated patients with hyperthyroidism met DSM-III criteria for organic affective syndrome. Thirty of these patients submitted 24-hour urine specimens for measurement of urinary free cortisol levels, and 31 were given a 1-mg dexamethasone suppression test (DST) before antihyperthyroidism therapy was started. There was no difference in the mean +/- SD urinary free cortisol excretion levels between depressed and nondepressed hyperthyroid patients. One nondepressed patient demonstrated nonsuppression (greater than 5 micrograms/dl) at 8:00 a.m. These results suggest that cortisol abnormalities as reflected by urinary free cortisol levels and DST findings are uncommon in patients with hyperthyroidism whether they are depressed or nondepressed.  相似文献   
956.
957.
Voluntary screening for human immunodeficiency virus (HIV) infection may help prevent the spread of the HIV epidemic if persons who test positive alter behaviors that may transmit infection. Protecting persons from unknowingly being exposed to HIV infection must be balanced against respecting the autonomy of individuals being screened. Seropositive patients may feel a stigma and be subjected to discrimination if confidentiality of test results is breached. In patients without high-risk behaviors, the positive predictive value of HIV testing may be substantially increased if tests are done in reference laboratories and if further confirmatory tests are run on a second blood specimen. For persons with high-risk behaviors, HIV testing can be recommended to those who want to reduce uncertainty about their HIV status or whose medical care would change if they were seropositive. Health care workers can maximize benefits of screening and minimize harm by educating and counseling patients before HIV testing, discussing the confidentiality of HIV test results, urging patients to disclose positive test results to sex partners, and advising patients on how to reduce high-risk behaviors.  相似文献   
958.
The vascular smooth muscle of the canine saphenous vein contains both postjunctional alpha-1 and alpha-2 adrenoceptors. Experiments were designed to elucidate the relationship between alpha adrenoceptor subtypes and sensitivity to calcium entry blockade. Rings of canine saphenous vein were mounted at optimal length for isometric tension recording in organ chambers filled with physiological salt solution. Nimodipine inhibited potassium-induced contractions and depressed contractions to norepinephrine in the presence of prazosin, an alpha-1 adrenoceptor antagonist, but not under control conditions or in the presence of the alpha-2 adrenoceptor antagonist, rauwolscine. Nimodipine depressed the maximal response to B-HT 920, an alpha-2 adrenergic agonist and St-587, a partial alpha-1 adrenergic agonist, but did not affect that to cirazoline, a full alpha-1 adrenergic agonist. However, after treatment with phenoxybenzamine, nimodipine depressed the response to cirazoline. Nimodipine inhibited contractions to tyramine under control conditions or after prazosin but not after rauwolscine. Incubation in calcium-free solution depressed responses to St-587 and B-HT 920 more than those to cirazoline. Incubation in calcium-free solution plus ethylene glycol bis(beta-aminoethyl ether)-N,N-tetraacetic acid abolished responses to all alpha adrenergic agonists. These results suggest that the sensitivity to calcium entry blockade of alpha adrenergic responses is not determined by the subtype of alpha adrenoceptor. Rather, our findings support the concept that it is the efficacy of the agonist-receptor interaction or the efficiency of receptor-response coupling that determines the effect of calcium entry blockade on the adrenergic response.  相似文献   
959.
960.
Nonmelanoma skin cancer mortality rates for recent decades show a biphasic pattern: from 1950-65 rates decreased; from 1966-86 rates increased. Age standardised mortality rates for 35-74 year old males increased from 1.6 (95% CI, 1.3-1.9) deaths per 100,000 person years in 1966-72 to 2.3 (95% CI, 2.0-2.5) deaths per 100,000 person years in 1980-86. Rates in women were lower but showed a similar percentage increase (46%), between these periods, to that observed for men (44%). The increased mortality from 1966 was presumably a result of increased ultraviolet exposure.  相似文献   
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