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At least 19 recordsLinked to original sources
PubMed1992

Short term versus long term psychotherapy in opioid dependence: a pilot study.

A multicenter prospective open study was performed in order to compare the effectiveness of 2 modalities of individual dynamic psychotherapy in a group of recently detoxified opioid dependent patients. Thirty four patients were assigned to receive either short-term dynamic psychotherapy (ST) or long-term dynamic psychotherapy (LT); both modalities were offered along with drug counselling. At the end of the treatment, the short term therapy group was followed up for 2 years, while the long term therapy group continued the follow up for one year, due to the different time span of the treatment approaches. Dropout rates for ST (47%) and LT (53%) patients were similar, and the re-entry rate for the ST group was superior (62.5% vs. 28.5%). Short term interventions appear to be at least as effective as long term interventions, and have the advantage of a high rate of program re-entry. Further studies conducted on larger samples are needed.

Adult↗
PubMed1985

Short term and long term effects of beta-adrenergic effectors and cyclic AMP on nitrendipine-sensitive voltage-dependent Ca2+ channels of skeletal muscle.

The effects of short term stimulation of beta-adrenergic receptors and elevations in intracellular cyclic AMP on nitrendipine-sensitive voltage-dependent Ca2+ channels of skeletal muscle cells in vitro has been studied using both the 45Ca2+ flux technique and [3H] nitrendipine-binding experiments. Isoproterenol increased the nitrendipine-sensitive 45Ca2+ influx under depolarizing conditions. The effects of isoproterenol were additive to those of depolarization and were antagonized by alprenolol. Half-maximal inhibition of 45Ca2+ influx induced both by depolarization and by isoproterenol occurred at a nitrendipine concentration of 1 nM. Treatments that resulted in an increased level of intracellular cyclic AMP, such as treatment with 1-methyl-3-isobutylxanthine, theophylline, dibutyryl cyclic AMP, or 8-bromocyclic AMP also resulted in an increased rate of 45Ca2+ entry via nitrendipine-sensitive Ca2+ channel. In contrast, long term treatment of myotubes in culture with isoproterenol and other compounds that increased intracellular cyclic AMP led to a large increase in the number of nitrendipine receptors. This increase was accompanied by a 4-10-fold decrease in the affinity of the receptors for nitrendipine. Alprenolol inhibited the long term effects of isoproterenol. In vivo treatment of 7-day-old chicks with reserpine and alprenolol produced a decrease in the number of skeletal muscle nitrendipine receptors. This decrease in receptor number was accompanied by an increase in the affinity of nitrendipine for its receptor by a factor of 4 to 5. These effects on the nitrendipine receptor were prevented by simultaneous injection of isoproterenol. The results are discussed in relation to the role of beta-adrenergic receptors and intracellular cyclic AMP in the regulation of skeletal muscle Ca2+ channels.

1-Methyl-3-isobutylxanthine↗
PubMed1978

[Aspects of long-term therapy using long-term neuroleptics -- experiences and viewpoints related to practice].

Practical aspects of long-term neuroleptic therapy are discussed in the light of the author's own experience and observations; reference is made to the relevant literature. The author looks at the terms "sociogenic" and "somatogenic" in the context of treatment of schizophrenia and finds them to be not so antithetic as has traditionally been supposed. He describes the advantages and disadvantages of long-term neuroleptic therapy, both oral and injectable. He analyses the starting of a rational long-term therapy in the light of various factors. He examines the effective spectra of the traditional long-term neuroleptica and finds little justification for the different specific indications claimed for the various drugs. On the example of selected patients suitable for this therapy he considers the causes of the disorders and the primary personality and early development of the subjects, discussing the nature of the illness from the nosological and clinical point of view, the social and economic situations, the type of follow-up, and the physician-patient relationship. Emphasis is laid on the significance of side-effects and of individual reactions to long-term neuroleptics. The questions how, when and where a patient should be put onto long-term medication are treated, with a critical comparison of high and traditional doses, and a recommendation that duration and stoppage of therapy be decided on the basis of individual case factors. Special attention is paid to the so-called pharmacogenic depressions. Other indications of long-term neuroleptic therapy are mentioned. The author considers the integration of pharmaco-therapy into a complex rehabilitation program to be essential; without this there can be no progress in the treatment of schizophrenia.

Adult↗
PubMed1978

[Effect of long-term suppression and long-term stimulation of ACTH secretion on the ultrastructure of tanycytes[].

The ultrastructure of the tanycyte ependyma in males of Wistar albino rats (160--180 g of weight) was studied under experimental long-term suppression of ACTH secretion and its long-term stimulation. The former effect was accomplished by daily (for 8 days) intraperitoneal administration of dexamethasone phsophate; the stimulation of ACTH secretion was achieved by bilateral adrenalectomy. The long-term suppression of the hypophyseal adrenocorticotrophic function was followed by the ultrastructural markers of an increased transport and secretory activity in the tanycytes (mainly in beta-tanycytes, i. e. the ependyma lining floor of the third ventricle): the increased amount of microvesicles in the Golgi area and in the vicinity of the particular membranous cavity system (MCS, according to the authors' definition), the appearance of some figures of exocytosis, the elevated amount of lipid inclusions. On the contrary, the long-term stimulation of ACTH secretion was followed by the ultrastructural changes of the opposite character. The data obtained are in agreement with the previously established fact that there is a negative correlation between the tanycyte activity and the hypophyseal adrenocorticotrophic activity. It is supposed that this correlation is regulated by a feedback mechanism and attest to the involvement of tanycytes in the inhibitory control of ACTH secretion. A possible substrate inhibiting ACTH secretion by the tanycytes is discussed.

Adrenalectomy↗
PubMed1991

Refining the temporal definition of an association at the neuronal level using long-term potentiation and long-term depression in the dentate gyrus.

This study sharpens the temporal definition of an association in the context of long-term synaptic modification of the monosynaptic projections from entorhinal cortex to dentate gyrus in the anesthetized rat. The ipsilateral projection produces a powerful postsynaptic excitation and shows synaptic potentiation following 7.5 ms trains. On the other hand, brief, high-frequency contralateral stimulation just after this powerful postsynaptic excitation is followed by long-term depression (LTD) at the synapses of this pathway. Therefore, based on the differential induction of long-term potentiation (LTP) or LTD, a cell can distinguish associated pre- and postsynaptic activation at a temporal resolution at least as small as 7.5 ms.

Animals↗
PubMed1990

Different voltage-dependent thresholds for inducing long-term depression and long-term potentiation in slices of rat visual cortex.

In the hippocampus and neocortex, high-frequency (tetanic) stimulation of an afferent pathway leads to long-term potentiation (LTP) of synaptic transmission. In the hippocampus it has recently been shown that long-term depression (LTD) of excitatory transmission can also be induced by certain combinations of synaptic activation. In most hippocampal and all neocortical pathways studied so far, the induction of LTP requires the activation of N-methyl-D-aspartate (NMDA) receptor-gated conductances. Here we report that LTD can occur in neurons of slices of the rat visual cortex and that the same tetanic stimulation can induce either LTP or LTD depending on the level of depolarization of the postsynaptic neuron. By applying intracellular current injections or pharmacological disinhibition to modify the depolarizing response of the postsynaptic neuron to tetanic stimulation, we show that the mechanisms of induction of LTD and LTP are both postsynaptic. LTD is obtained if postsynaptic depolarization exceeds a critical level but remains below a threshold related to NMDA receptor-gated conductances, whereas LTP is induced if this second threshold is reached.

2-Amino-5-phosphonovalerate↗
PubMed1991

Comparison of the results of electrophysiologic testing after short-term and long-term treatment with amiodarone in patients with ventricular tachycardia.

The results of electrophysiologic testing after short-term and long-term treatment with amiodarone were compared in 71 patients with ventricular tachycardia. Electrophysiologic testing was performed in the baseline state after 11 +/- 3 days of treatment with 1.2 to 2.4 gm/day of amiodarone, and after 13 +/- 4 weeks of therapy with a daily amiodarone dose of 400 mg. After short-term therapy, 62% of the patients had an adequate response to amiodarone. In 27 patients who were hemodynamically unstable, ventricular tachycardia was induced and became noninducible or hemodynamically stable after combination therapy with a class I agent. Among 18 patients who did not have inducible ventricular tachycardia after short-term therapy, eight (44%) had inducible, hemodynamically unstable ventricular tachycardia after long-term treatment with amiodarone. On the other hand, six of the 27 patients who had hemodynamically unstable ventricular tachycardia after short-term therapy had an adequate response after long-term treatment with amiodarone. Therefore an adequate electrophysiologic response after short-term therapy does not guarantee a similar response after long-term treatment, and an inadequate response after short-term therapy does not always predict a similar response after long-term therapy.

Aged↗
PubMed1975

Short-term versus long-term hospitalization in a private psychiatric facility: a follow-up study.

A follow-up study was made of 43 short-term and 42 long-term ex-patients 18 months after their discharge from a private psychiatric hospital. The short-term sample was different from the long-term sample on many preadmission and hospitalization variables, but it was much less different on the follow-up variables. Although most ex-patients in both samples were functioning well at follow-up, the long-term sample was doing somewhat better in all areas, according to both the former patients and their nearest relatives. Differences between the improvement of those in the short- and long-term sample increased when tested by diagnosis; long-term schizophrenic patients improved the most.

Adult↗
PubMed1991

The effectiveness of short-term versus long-term exposures to Photofrin II in killing light-activated tumor cells.

Asynchronous populations of mouse EMT-6 tumor cells were exposed to various doses of 630-nm light in slowly stirred aerobic suspensions after both short-term and long-term exposures to Photofrin II. All survival curves are characterized by a "threshold" light dose below which no cell inactivation occurs followed by a steep light-dose response. Both the shoulder widths and the inactivation curve slopes are functions of Photofrin II concentration. After high doses of light where survival levels are 0.003 and lower, "resistant tails" are observed on some survival curves. Light doses required to inactivate 50% of tumor cell populations were obtained from whole survival curves and their reciprocals (1/D50% survival) used as inactivation "rates". The amount of Photofrin II within cells was measured by a fluorescence assay. Per unit of fluorescence, this photosensitizer is at least 10 times more effective after long-term than after short-term exposures. After long-term exposures, both fluorescence activity and photosensitizing effectiveness are retained in washed cells for several hours. After short-term exposures, a majority of both the fluorescence and photosensitizing activity is lost by multiple washings or stirring in tissue culture medium without drug. These data suggest that the cellular compartments associated with photosensitization after short-term exposures to Photofrin II are probably different from the cellular compartments associated with photosensitization after long-term exposures to the drug. The data are consistent with known properties of the monomeric and oligomeric components of Photofrin II.

Animals↗
PubMed1991

Prescription and intake patterns in long-term and ultra-long-term benzodiazepine treatment in primary care practice.

Pharmacoepidemiological data show that long-term treatment accounts for a considerable part of benzodiazepine prescriptions in primary care practice. Prescription and intake patterns were, therefore, investigated in a study of 196 patients who had been treated with benzodiazepines for longer than six months by internists or general physicians in private practice. Patients were 64 years of age on average, half of them being 65 years or older. Females were in the majority (73.5%). The average duration of tranquilizer or hypnotic intake was 11.0 years, or 5.3 years for the current benzodiazepine medication. The mean daily dose was 9 mg diazepam equivalent. All benzodiazepine hypnotics and 61% of benzodiazepine tranquilizers had been prescribed solely for night-time use. Only 6% of the patients were taking benzodiazepines as single medication: on average they were taking 3.1 additional types of medication for other conditions, these being predominantly cardiac and antirheumatic/analgesic in nature. One in five patients was taking additional psychotropic medication. The compliance coefficient was on average 0.8, showing that patients did not tend to abuse benzodiazepines, with noncompliance generally being similar to noncompliance with other forms of medication.

Adult↗
PubMed1977

Ultrastructure of muscle biopsies in recent, short-term and long-term juvenile diabetes.

Muscle biopsies from juvenile diabetics were studied by electron microscopy and the results correlated to earlier published light microscopical abnormalities of the same biopsies. A total of 32 striated muscle biopsies from 29 juvenile recent, short-term and long-term diabetes were examined. The ages ranged from 16 to 43 years with a diabetes duration from 1 week to 32 years. The material was compared with biopsies from healthy persons of the same ages. The electron microscopy revealed degenerative changes of the striated muscle fibres which signify a neurogenic atrophy. No myopathic alterations were found. The capillaries in both the recent and long-term diabetics showed an extremely pronounced pinocytosis indicating an increased metabolic activity. In the long-term group the intramuscular capillaries both from upper and lower extremities displayed a definitely thickened basement membrane. In the recent and short-term group the capillary wall alterations were debatable. The motor end plate in the recent diabetics revealed minimal alterations. Contrary to this the long-term group showed severe alterations with occasional disappearance of the nerve fibres.

Adolescent↗
PubMed1978

Genetic dissection of short-term and long-term facilitation at the Drosophila neuromuscular junction.

Transmitter release at the Drosophila larval neuromuscular junction may be increased by previous activity of the nerve. This facilitation phenomenon involves at least two processes, one short-term and other long-term. These are shown to based on different mechanisms because (i) a mutant was found that had abnormal long-term facilitation but normal short-term facilitation; and (ii) long-term facilitation was eliminated by tetrodotoxin or by removing external Na+ but short-term facilitation was not. In long-term facilitation, there was a prolonged release of transmitter due to a prolonged Ca2+ sensitivity of the presynaptic terminal after each nerve stimulus. The cause of this is probably accumulation of Na+ inside the nerve terminal.

Animals↗
PubMed1991

Comparative efficacy of short-term versus long-term cefoxitin prophylaxis against postoperative infection after radical hysterectomy: a prospective study.

We report the results of a randomized, double-blind comparison of short-term versus long-term cefoxitin prophylaxis against infections after radical abdominal hysterectomy with pelvic and para-aortic lymphadenectomy. Of 113 evaluable patients, 54 (47.8%) received short-term (three doses) and 59 (52.2%) long-term (12 doses) prophylaxis with intravenous cefoxitin (2 g per dose). No significant differences in demographics, preoperative risk factors, or clinical course were detected between the two groups; nor did we detect significant differences in the incidence of surgical-site-related infections (7.4 versus 5.1%, respectively, P = .61), postoperative urinary tract infection, or other febrile morbidity. We conclude that short-term and long-term cefoxitin prophylaxis are equally effective for the prevention of post-operative surgical-site-related infections after radical hysterectomy.

Adult↗
PubMed1979

Serum prolactin levels in short-term and long-term use of inert plastic and copper intrauterine devices.

Serum prolactin values were assessed in 59 normally menstruating parous women; groups were divided with respect to short-term (6 weeks) and long-term (4-60 months) use of either the inert plastic IUD (Saf-T-Coil or Lippes Loop) or copper IUD (Cu-7). Preinsertion values served as controls in the short-term study while a separate control group using barrier contraception was used in the long-term study. Prospective analysis of short-term IUD use and retrospective analysis of long-term IUD use revealed no significant differences in mean hPRL compared to control values. Both short- and long-term mean values were within the normal range for serum hPRL. In addition, duration of use had no significant effect on hPRL values.

Adolescent↗
PubMed1989

Short-term and long-term changes of left ventricular volumes during rate-adaptive and single-rate pacing.

To evaluate the adaptation of the heart to exercise during pacing, 15 patients with permanent endocardial pacemakers were studied; nine patients had atrioventricular universal (DDD) pacemakers (Symbios 7005) and six patients had activity detecting rate-responsive ventricular (VVIR) pacemakers (Activitrax 8403). Left ventricular function in each patient during rate variable pacing was compared to ventricular function during VVI single-rate pacing. End-systolic and end-diastolic volume changes during exercise were measured by radionuclide angiography and the amount of volume change was used to assess left ventricular function. Both short-term (within 4 hours) and long-term measurements (after at least 4 weeks) were made at rest and at 50% of the maximal exercise capacity in DDD or VVIR mode and were compared with VVI single-rate pacing. All patients, when changed from DDD or VVIR mode to VVI single-rate pacing showed a significant increase of the end-diastolic volume during exercise, which increased even more after long-term VVI pacing. During long-term rate variable pacing, there was no increase of the end-diastolic volume during exercise. DDD or VVIR pacing initially showed a substantial increase of the end-systolic volume during exercise combined with a decrease of left ventricular ejection fraction, suggesting a decrease of the left ventricular contractility. After 4 weeks, contractility improved both with DDD and VVIR pacing. We conclude that short-term DDD and VVIR pacing induces a temporary impairment of left ventricular function that improves after 4 weeks, whereas long-term VVI pacing is associated with left ventricular dilatation even at moderate levels of exercise.

Adaptation, Physiological↗
PubMed1991

Short-term and long-term memory in single cells.

Many approaches have been used to study short- and long-term memory. Bacteria detect chemical gradients using a memory obtained by the combination of a fast excitation process and a slow adaptation process. This model system, which has the advantages of extensive genetic and biochemical information, shows no features of long-term memory. To study long-term memory, neural cell line systems have been developed that exhibit two phenomena associated with learning and memory, habituation and potentiation. The expression of these phenomena in clonal cell lines, devoid of synaptic connections, makes it possible to study the biochemical and molecular mechanisms that contribute to short-term and long-term memory.

Acetylcholine↗