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1.
Methamphetamine is a potent and indirect dopaminergic agonist which can cause chronic brain dysfunctions including drug abuse, drug dependence and drug-induced psychosis. Methamphetamine is known to trigger molecular mechanisms involved in associative learning and memory, and thereby alter patterns of synaptic connectivity. The persistent risk of relapse in methamphetamine abuse, dependence and psychosis may be caused by such alterations in synaptic connectivity. EphA5 receptors constitute large families of tyrosine kinase receptor and are expressed almost exclusively in the nervous system, especially in the limbic structures. Recent studies suggest EphA5 to be important in the topographic projection, development, and plasticity of limbic structures, and to be involved in dopaminergic neurotransmission. We used in situ hybridization to examine whether methamphetamine alters EphA5 mRNA expression in the brains of adult male Wister rats. EphA5 mRNA was widely distributed in the medial frontal cortex, cingulate cortex, piriform cortex, hippocampus, habenular nucleus and amygdala. Compared to baseline expression at 0 h, EphA5 mRNA was significantly decreased (by 20%) in the medial frontal cortex at 24 h, significantly increased (by 30%) in the amygdala at 9 and 24 h, significantly but transiently decreased (by 30%) in the habenular nucleus at 1 h after a single injection of methamphetamine. Methamphetamine did not change EphA5 mRNA expression in the cingulate cortex, piriform cortex or hippocampus. Our results that methamphetamine altered EphA5 mRNA expression in rat brain suggest methamphetamine could affect patterns of synaptic connectivity, which might be responsible for methamphetamine-induced chronic brain dysfunctions.  相似文献   
2.
Infection is a common complication of stroke and is associated with unfavorable outcomes. Although nutritional intervention reduces the risk of postoperative infection, the impact of specific nutritional products remains unclear. From a hospital management perspective, we aimed to determine whether the provision of specific types of enteral nutrition in acute stroke patients affects infection control and hospital costs. In all, 45 acute hemorrhagic stroke patients receiving enteral nutrition in a single center (April 2017–March 2019) were retrospectively assessed. Patients were divided into two groups according to nutritional interventions: the 1.0-group with general nutrition (1.0 kcal/mL) (24 patients) and the 1.5+α-group with an initial high-protein, whey peptide-digested liquid diet (1.5 kcal/mL), followed by a highly fermentable fiber-containing liquid diet (1.5 kcal/mL initiated after 4 days) (21 patients). Changes in body mass index (BMI), duration of antibiotic use, incidence of postoperative infection, and medical cost were evaluated. Baseline patient characteristics were similar between groups. The mean BMI change was lower in the 1.5+α-group than in the 1.0-group, and the mean duration of antibiotic use throughout hospitalization was 12.8 and 18.3 days, respectively. Antibiotic use in the 1.5+α-group was lesser than that in Japanese patients from other hospitals. The incidence of postoperative infections was lower in the 1.5+α-group. Injection costs for the 1.5+α group (615 USD/patient) were lower than those for the 1.0-group. Enteral nutrition provided to acute stroke patients reduced the risk of hospital infection and medical costs.  相似文献   
3.
Fischer 344 (F344) and Lewis (LEW) rats differ in physiological regulation of the limbic-hypothalamo-pituitary-adrenal (LHPA) axis, such that F344 rats exhibit greater LHPA axis responses to a variety of stimuli. Furthermore, LHPA axis activity has been implicated in the development of sensitization to abused drugs, and F344 rats exhibit greater behavioral sensitization to psychostimulants. Accordingly, we hypothesized that there may be some overlap between the neurobiological mechanisms that underlie these strain differences in LHPA axis activity and in behavioral sensitization to psychostimulants. We examined the effects of acute and repeated methamphetamine (4 mg/kg) treatments on the regulation of hippocampal glucocorticoid receptors (GR mRNA) and mineralocorticoid receptors (MR mRNA) in F344 and LEW rats. Our results showed that acute treatment with methamphetamine (MAP) does not alter the level of expression of GR or MR mRNA in both strains. However, repeated treatments with MAP decreased the expression of hippocampal GR, but not MR mRNA specifically in F344 rats. The same repeated treatments had no effect on either GR or MR mRNA in LEW rats. This selective MAP regulation of the level of expression of hippocampal GR mRNA in F344 suggests that these receptors may play a role in the development of behavioral sensitization to MAP in this strain. The lack of alteration in hippocampal GR mRNA in LEW rats suggests that plasticity of hippocampal GR may not be critical for the development of behavioral sensitization to MAP in this strain.  相似文献   
4.
In recently reported cases of ventricular parasystole, it was shown that after exercise the parasystolic cycle length is prolonged, in contrast to a shortening of the sinus cycle length, whereas during standing the parasystolic cycle length and the sinus cycle length both shortened. In this report, to explore whether the same features as occur in ventricular parasystole are seen in atrial parasystole, effects of exercise and standing on the parasystolic cycle length were investigated in two men with atrial parasystole. The atrial parasystolic cycle length was prolonged after exercise, whereas it shortened during standing, similar to what occurs in ventricular parasystole. This is the first report to show such changes of cycle length in atrial parasystole. These findings suggest that in atrial parasystole, as in ventricular parasystole, influences on the parasystolic cycle length do not always act in the same direction as those on sinus cycle length.  相似文献   
5.
Intracerebral metastasis in osteosarcoma is extremely rare. A 14-year-old girl who had previously been operated upon for osteosarcoma of the femur presented with seizures and left hemiparesis. A right parietal lesion with calcification and brain oedema was found. After resection of the mass, pathology revealed an osteosarcoma metastasis.  相似文献   
6.
Summary:  Purpose: To examine the effects of cognitive–motor function on EEG discharges and the neuropsychological mechanisms of seizure induction in patients sensitive to cognitive–motor tasks.
Methods: Four hundred eighty patients with epilepsies were subjected to cognitive tasking, termed "neuropsychological EEG activation (NPA)." It consisted of reading, speaking, writing, written calculation, mental calculation, and spatial construction. Furthermore, patients showing a provocative NPA effect were subjected to a detailed NPA protocol to identify the possible precipitating factors, which consisted of simple hand movements, action programming requiring hand movement, and thinking activity not requiring hand movement.
Results: NPA had an inhibitory effect on EEG discharges in 133 (63.9%) of 208 patients with discharges in the awake EEG. Conversely, NAP had a provocative effect in 38 (7.9%) of 480 patients. In 32 of the 38 patients, the precipitating factor was action programming. Among them, five showed a precipitating factor restricted to linguistic activity, and the remaining 27 were affected by various action-programming factors including both linguistic and praxic activities. In four of 38 patients, the precipitating factor was thinking, predominantly linguistic tasks in one patient and spatial tasks in three patients. No patient had a precipitating factor identified as motor activity.
Conclusions: These results suggest that cognitive–motor function has an inhibitory effect on EEG discharges in the majority of epilepsy patients and a provocative effect in some patients, and that seizures of the patients showing a provocative NPA effect are precipitated by action programming or thinking activity.  相似文献   
7.
In order to clarify the initial formation of keratin from prekeratin molecules, we undertook a pulse-chase experiment using [U-14C]-glycine labelled prekeratin subunit mixture in vitro. The experiment was carried out at 37°C for 3 hours using a specimen (3 mm2×0.1 mm) in Dulbecco minimum essential medium (MEM) containing 14C-glycine. Incorporation of 14C-glycine into the prekeratin molecules was exhibited in six prekeratins (M.W. about 71, 69, 62, 55, 52 and 49 K, respectively), and the highest incorporated molecule among them was the 55K-prekeratin molecule. After 30 minutes at 37°C in the above medium, the intact specimens were transferred into a comparable medium free of 14C-glycine, and further incubated for 4 hours. The 52K- and 62K-prekeratin molecules had increased at 60 minutes after being chased, as compared with the starting radioactive value. From this result, it was suggested that the two prekeratin molecules might be intermediates in the initial stage of keratinization. Moreover, the human epidermal homogenate was more effective in converting the prekeratin into keratin molecules. Some factor(s) may be present in the fraction which convert the prekeratin into keratin molecules.  相似文献   
8.
Summary N-acetyl-β-D-glucosaminidase(NAG) is a lysosomal enzyme predominantly located in renal proximal tubules. In idiopathic hypoparathyroidism(IHP), 100 Units of human PTH(1–34) increased urinary excretion of NAG from 0.029±0.027 to 0.173±0.035 U/1GF (p<0.05) in two patients before treatment and from 0.025±0.004 to 0.189±0.092U/1GF (p<0.02) in four patients during treatment with active vitamin D3 (1,25(OH)2D3 or 1αOHD3). In pseudohypoparathyroidism(PHP), PTH did not significantly increase the urinary excretion of NAG in one patient with before treatment (0.048 to 0.025 U/1GF) and four patients during treatment with active vitamin D3 (0.018±0.008 to 0.036±0.015 U/1GF). Increase in urinary excretion of NAG after injection of PTH may be a new indicator of renal effect of PTH.  相似文献   
9.
10.
OBJECTIVE: A rare case of ruptured kissing aneurysms on the right internal carotid-posterior communicating artery (ICPCA) and -anterior choroidal artery (ICAchA) is reported. CASE: A 47-year-old female was transferred to our hospital because of subarachnoid hemorrhage (SAH). Cerebral angiography revealed two aneurysms on the right ICPCA and ICAchA. Right frontotemporal craniotomy was performed to obliterate them on the day of admission. Despite the presence of angiographical cleavage, these two aneurysms were attached to each other tightly, and it was extremely difficult to dissect the space between them and premature rupture occurred. A Sugita long straight clip was inserted parallel to internal carotid artery to obliterate the body of ICAchA aneurysm and the neck of ICPCA aneurysm. Another straight clip was applied to the neck of the former aneurysm. Both PCA and AchA could be secured successfully. Postoperatively, although she developed symptomatic vasospasm on the 10th day, she discharged without any neurological deficits 40 days later. CONCLUSIONS: Because of the difficulty in dissection of aneurysms, the operation for kissing aneurysms has been recognized as hazardous and challenging since Jefferson. We emphasize that a clipping technique described above should be kept in mind as a safe value, though meticulous dissection of each aneurysmal neck followed by independent neck clipping is reasonable.  相似文献   
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