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61.
INTRODUCTION: Acute mast cell leukemia is a rare and severe disease. We report herein a case associated with a flush syndrome. CASE REPORT: A 44-year-old man, presented with a flush of face and trunk. Bone marrow was infiltrated with immature mast cells. In spite of chemotherapy and bone marrow transplantation the patient deceased. DISCUSSION: Pheochromocytoma, carcinoid tumor, and mastocytosis are associated with a flush syndrome. In our patient the diagnosis was an acute mast cell leukemia. Acute mast cell leukemia can follow systemic mastocytosis or occur de novo. This disease is of poor prognosis. No treatment is available.  相似文献   
62.
We report the case of a woman who, at the age of 27, developed a cerebral arterial occlusion. The laboratory investigations showed an anti-human beta2-glycoprotein I antibody, but no other biological sign of antiphospholipid antibody syndrome or autoimmune disorders. The patient otherwise presented with diabetes and moderate obesity. The species specificity of anti-beta2-glycoprotein I antibodies probably explains the discrepancy between false negative results for antiphospholipid antibodies assayed by clotting and ELISA studies and positivity for anti-human beta2-glycoprotein I. Further studies will be important to evaluate the frequency of such antibodies, as well as their value as a risk factor for venous and arterial thrombosis, and their signification within the antiphospholipid antibody syndrome.  相似文献   
63.
OBJECTIVE: To discuss the case of an 8-yr-old boy with an aneurysmal bone cyst of the right proximal humerus, including the features imaged on plain film radiography, computed tomography (CT), magnetic resonance imaging (MRI), including spin echo and fast field echo imaging. CLINICAL FEATURES: The patient suffered for 1 yr from intermittent but progressive pain in his right upper arm and shoulder area. There was no history of trauma or known systemic disease. There was decreased range of motion in abduction of the glenohumeral joint and pain on focal pressure along the deltoid muscle. A complete imaging evaluation consisting of plain film radiography, CT and MRI was performed, which revealed the classical imaging features of an aneurysmal bone cyst. An additional cystic lesion was detected by the MRI that was not appreciated on the plain films or CT. INTERVENTION AND OUTCOME: The patient was referred for biopsy to confirm the preliminary diagnosis of aneurysmal bone cyst. No treatment was instituted. CONCLUSION: Evaluation of aneurysmal bone cyst may be completed with CT scanning and more specifically with MRI MRI coronal T2, weighted images are advantageous for visualization of the main cystic lesion and any additional cysts. Fast field echo images show a better contrast between the cyst and bone marrow with extension of the cyst into the epiphysis as evident in this case. Follow-up studies revealed complete healing of the cyst with only residual densities in the humeral metaphyseal area.  相似文献   
64.
Cholera toxin (CT) was shown to bind to immobilized Ni2+ ion. The affinityof CT for the complex required the presence of the Ni2+ ion, since CT wasunable to bind in its absence. Binding was mediated by the B-subunit (CTB)as both CT and CTB bound to the resin, but not the A- subunit (CTA).Binding was reversible in the presence of imidazole and suggested that theaffinity of CT for the Ni2+ ion was mediated by His residues. Theheat-labile enterotoxin of Escherichia coli (LT), which is closely relatedto CT, was unable to bind to the Ni2+ ion. Comparison of amino acidsequences revealed the presence of three His residues in CT (positions 13,57 and 94), but only one in LT (position 57). To confirm that the residuesat positions 13 and 94 of CTB were responsible for the binding, they werechanged to residues found in LTB. Changing His13-->Arg completelyabrogated the ability of CTB to bind to Ni2+ ion. In contrast, the mutationof His 94-->Asn reduced, but did not abrogate, the ability of CTB tobind to Ni2+ ion. Based on calculated interatomic distances, it is unlikelythat His13 and His94 are part of the same complex. There appear to be twoseparate binding sites, with the principal site involving His13 and a muchweaker site involving His94. This latter site can only participate inbinding if the complex involving His13 has formed.  相似文献   
65.
Flow cytometry techniques, usually employed to characterize cellular populations, are reported here to be a valuable tool to approach the study of subcellular organelle functioning. Chromaffin granules rendered fluorescent by using an antibody against their membrane protein, synaptophysin, are detectable by flow cytometry. Moreover, these storage granules are able to transport the fluorescent ATP analogue, epsilon-ATP (1,N6-ethenoadenosine 5'-triphosphate), and the resulting granular fluorescence increase can also be followed by this technique. The saturation studies show a non-hyperbolic kinetic behaviour, with a two step curve. The K0.5 values were 0.26 and 2.5 mM and Hill numbers 1 and 6 respectively. In addition, an unexpected granular size increase, which was dependent on the epsilon-ATP concentration, occurred together with the fluorescence increase. Other nucleotide triphosphate substrates of V-ATPase, such as ATP or GTP, but not the non-hydrolyzable analogue ATP gamma S (adenosine 5'-O-(3-thiotriphosphate), mimic this effect, which exhibited sigmoidal saturation curves with K0.5 values of 1.8 and 3.1 mM for ATP and epsilon-ATP respectively. The V-ATPase inhibitors, suramin, EGTA or EDTA significantly reduced the granular size increase in the presence of ATP. Extragranular addition of noradrenaline has no effect by itself on the granular size, but significantly reduced the granular size increase induced by ATP. This effect was reversed by the amine transport inhibitor reserpine. The granular size increase induced by ATP was more effective in the presence of Cl- than Br- or I-. Moreover, no increase occurred in the presence of F- or acetate. The Cl- channel blockers were poorly effective, and only 2-(phenylamino)-benzoic acid (DPC) exhibited an effect on the ATP-induced granular size increase.  相似文献   
66.
OBJECTIVE: To measure grocery chain pharmacists' work-related behaviors to assess the impact of a Pharmaceutical Care Certificate Program (PCCP) and other future interventions intended to alter pharmacists' practice behaviors. DESIGN: This study used multidimensional work sampling (MWS), a work measurement methodology that breaks "work" into three components: activity (what was done), contact (with whom the activity was performed), and function (the purpose or objective of the activity). Pharmacists were signaled at random intervals during the workday by a random signal generator. A selection was made from a list of items in each of the three dimensions of work to form an activity-contact-function combination code that described the work-related behavior at that point in time. SETTING AND PARTICIPANTS: Pharmacists in 15 grocery chain stores in the Indianapolis area; 20 pharmacists were enrolled in Purdue University's PCCP and 10 served as controls. Data were collected for a period of six weeks during April through June 1997 before the beginning of the PCCP program. MAIN OUTCOME MEASURES: Pharmacists' work-related behaviors. RESULTS: Writing/keyboarding was the most frequently recorded activity (22%), followed by one-to-one meetings (21.6%), and drug preparation (18%). Pharmacists spent most of their time working alone (62.9%), while a smaller but still substantial proportion of time was spent interacting with patients (17.9%). The most frequently recorded purpose (i.e., function) of pharmacists' activities was drug distribution (23.9%), followed by personal time (12.4%), receiving or transferring a medication order (10.2%), and patient counseling (6.6%). Out of a possible, 1,760 activity-contact-function combinations, 10 accounted for 46.3% of all reported observations, with "Prepare drug-Self-Drug distribution" representing the most frequently recorded activity-contact-function combination (15.7%). CONCLUSION: MWS is useful in helping grocery chain management better understand how pharmacy personnel are currently being utilized. This study provides a baseline for evaluating the impact of training programs or other alterations in the practice environment on pharmacists' work-related behaviors.  相似文献   
67.
Retrospective analyses of data from the authors' program of research on hypnosis and memory are presented, with special emphasis on effects observed among low hypnotizable individuals. In Experiment 1, participants completed seven forced-recall trials in an attempt to remember a series of pictures that had been shown 1 week earlier. For half the participants, the middle five trials were carried out using hypnotic procedures; the remaining participants performed all recall attempts in a motivated waking condition. Hypnosis failed to enhance correct recall for either high or low hypnotizable participants beyond the hypermnesia and reminiscence effects associated with repeated retrieval attempts over time. However, whereas high hypnotizable participants produced substantial numbers of confident recall errors (i.e., intrusions) independent of the use of hypnosis, low hypnotizable participants exposed to hypnotic procedures reported significantly more intrusions than their counterparts in the waking condition. In Experiment 2, participants were asked to identify whether specific recollections, reported during two forced-interrogatory recall tests conducted 1 week earlier, had originated in the first or second of those tests. A general bias to misattribute previously reported recollections to the first of two recall occasions was observed; however, the effect was greatest among low hypnotizables who had undergone the second recall attempt in hypnosis. The findings imply that highly hypnotizable individuals are not unique in their vulnerability to distortions of memory induced by hypnotic techniques. Individuals of lesser hypnotic capacity also manifest memory alterations when exposed to such procedures.  相似文献   
68.
69.
OBJECTIVE: To investigate the roles of brain angiotensin II and C-type natriuretic peptide (CNP) in the hypertensive mechanism of deoxycorticosterone acetate (DOCA)-salt hypertension. METHODS: We injected 50 microg/kg CV-11 974, an angiotensin II type-1 receptors antagonist, 30 nmol/kg CNP-22, or the vehicle (artificial cerebrospinal fluid) into the cerebral ventricle or intravenously 5 min before the intracerebroventricular infusion of 1.5 mol/I NaCl solution for 30 min into either male normotensive Wistar rats or DOCA-salt hypertensive rats anesthetized with urethane, and their arterial pressures and heart rates were continuously recorded. Blood (2 ml) was collected at the end of the infusion for the measurement of plasma concentration of arginine vasopressin. We infused 10 or 50 microg/kg per day CV-11 974, 10 or 50 nmol/kg per day CNP-22, or the vehicle (1 microl/h) into the cerebral ventricles of DOCA-salt hypertensive rats for 7 days by using osmotic minipumps, and measured their systolic arterial pressures, pulse rates, and urinary excretions of vasopressin. RESULTS: Intracerebroventricular pre-administrations of CV-11 974 and of CNP-22 inhibited increases in mean arterial pressure, heart rate, and plasma vasopressin concentration induced by intracerebroventricular infusion of 1.5 mol/l NaCl into normotensive rats; increases in hemodynamics and plasma level of vasopressin induced by intracerebroventricular infusion of 1.5 mol/l NaCl were suppressed by intracerebroventricular pre-injections of CV-11 974, but not of CNP-22, into DOCA-salt hypertensive rats. Continuous intracerebroventricular infusions of 50 microg/kg per day CV-11 974 attenuated hypertension in DOCA-salt treated rats, accompanied by a reduction in urinary excretion of vasopressin. Continuous intracerebroventricular infusions of 50 nmol/kg per day CNP-22, however, affected neither hypertension nor urinary excretion of vasopressin in DOCA-salt hypertensive rats. CONCLUSION: Brain angiotensin II could play a role in the pressor mechanism of DOCA-salt hypertension by increasing release of vasopressin via type 1 receptors. That brain CNP has an inhibitory effect on release of vasopressin in acute experiments indicates that the impairment of this inhibitory effect of brain CNP on secretion of vasopressin could be involved in the pathogenesis of DOCA-salt hypertension in rats.  相似文献   
70.
PURPOSE: Ischemic neurodegeneration contributes to many retinal diseases. An isolated retina model has been used to examine the neuronal cell death induced by deprivation of oxygen and glucose (simulated ischemia) as a model for ischemic disease. METHODS: Neurodegeneration in the isolated chick embryo retina was induced by simulated ischemia and assessed using biochemical (lactate dehydrogenase release) and morphologic (light microscopy) techniques. RESULTS: Simulated ischemia led to lactate dehydrogenase release gradually in a period of 6 to 24 hours. Light microscopic observations demonstrated morphologic cell degeneration well before lactate dehydrogenase release occurred. N-Methyl-D-aspartate (NMDA) and non-NMDA receptor blockers individually provided partial protection, and the combination was fully protective. No protection was provided if the antagonists were added after simulated ischemia. When NMDA receptors were blocked by MK-801, cyclothiazide, an inhibitor of desensitization at non-NMDA receptors, enhanced lactate dehydrogenase released after 1 or 2 hours of simulated ischemia. Low concentrations of glucose effectively prevented lactate dehydrogenase release, despite anoxic conditions. CONCLUSIONS: The isolated retina provided a convenient system to characterize quantitatively ischemic cell death. Retinal ischemic neurodegeneration is an excitotoxic process that involves overactivation of NMDA and non-NMDA glutamate receptors. Blockade of both of these receptor subtypes was necessary for complete neuroprotection. Receptor desensitization played a protective role. If even low concentrations of glucose were delivered to an ischemic retina in vitro, substantial neuroprotection could be achieved. This may have implications for the management of acute retinal ischemic episodes.  相似文献   
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