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RODERICH WALTER PAULA L. HOFFMAN JOSEFA B. FLEXNER LOUIS B. FLEXNER 《Chemical biology & drug design》1980,16(5):482-486
[Ile3, Arg8]. vasopressin (arginine-vasotocin), as well as the C-terminal tripeptides of the neurohypophyseal hormones arginine and lysine vasopressin, Pro-Arg-Gly-NH2 and Pro-Lys-Gly-NH2, were protective against puromycin-induced amnesia in mice when administered 24h before training. The N-protected tripeptide derivative, Z-Pro-Lys-Gly-NH2, was effective when given 5 days before training. The effectiveness of all peptides to attenuate puromycin-induced amnesia decreased as the interval between training and peptide treatment increased, indicating that the peptides influence memory processes, rather than general arousal. Z-Pro-Lys-Gly-NH2 was active at 24h after training, when the other peptides were no longer effective. Although it seems clear that neurohypophyseal hormones per se can attenuate puromycin-induced amnesia, these results are in line with the possibility that some portion of hormone action may be mediated via formation of longer-lived hormone fragments in the CNS. 相似文献
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K. L. VENKATACHALAM M.D. LISA J. FANNING ELAINE A. WILLIS† DOUGLAS S. BEINBORN DAVID J. BRADLEY M.D. Ph.D. YONG-MEI CHA M.D. WIN-KUANG SHEN M.D. SAMUEL J. ASIRVATHAM M.D. LAWRENCE J. SINAK M.D. DOUGLAS L. PACKER M.D. THOMAS M. MUNGER M.D. PAULA J. SANTRACH M.D. ‡ PAUL A. FRIEDMAN M.D. 《Journal of cardiovascular electrophysiology》2009,20(3):280-283
Introduction: Emergency pericardiocentesis during electrophysiology procedures is often associated with significant aspiration of pericardial blood, requiring transfusion. We sought to assess the feasibility of urgent use of an autologous blood recovery system in the electrophysiology laboratory to autotransfuse blood aspirated from the pericardium.
Methods and Results: We retrospectively analyzed Mayo Clinic electrophysiology records for patients who had ablation procedure-related pericardial effusions requiring emergency pericardial drainage during an 8-month period. An autologous blood recovery system was used during pericardiocentesis to separate and clean packed red blood cells from the pericardial aspirate. These cells were returned acutely to the patient intravenously. The procedural safety, aspirated and autotransfused volumes, and efficacy of this approach were evaluated. During the study period, nine patients underwent pericardial drainage with autotransfusion using a cell-salvage instrument during electrophysiology procedures. The mean aspirated volume was 1,078 mL, with a mean autotransfused volume of 390 mL. For four patients, all with aspirated volumes of 1,100 mL or less, autotransfusion alone was sufficient to maintain hemodynamic stability and avoid allogeneic transfusion. One patient required surgical intervention because of ongoing pericardial bleeding. The ablation procedure was completed after aspiration in two patients. No procedural complications related to the use of the cell-salvage system occurred.
Conclusion: Autologous blood recovery during pericardiocentesis is safe, convenient, and feasible. With early use it may decrease or eliminate the need for allogeneic blood transfusion and, in selected cases, may permit completion of the ablation procedure. 相似文献
Methods and Results: We retrospectively analyzed Mayo Clinic electrophysiology records for patients who had ablation procedure-related pericardial effusions requiring emergency pericardial drainage during an 8-month period. An autologous blood recovery system was used during pericardiocentesis to separate and clean packed red blood cells from the pericardial aspirate. These cells were returned acutely to the patient intravenously. The procedural safety, aspirated and autotransfused volumes, and efficacy of this approach were evaluated. During the study period, nine patients underwent pericardial drainage with autotransfusion using a cell-salvage instrument during electrophysiology procedures. The mean aspirated volume was 1,078 mL, with a mean autotransfused volume of 390 mL. For four patients, all with aspirated volumes of 1,100 mL or less, autotransfusion alone was sufficient to maintain hemodynamic stability and avoid allogeneic transfusion. One patient required surgical intervention because of ongoing pericardial bleeding. The ablation procedure was completed after aspiration in two patients. No procedural complications related to the use of the cell-salvage system occurred.
Conclusion: Autologous blood recovery during pericardiocentesis is safe, convenient, and feasible. With early use it may decrease or eliminate the need for allogeneic blood transfusion and, in selected cases, may permit completion of the ablation procedure. 相似文献
16.
ANDERSON G; COLES ET; CRANE M; DOUGLAS AC; GIBBS AR; GEDDES DM; PEEL ET; WOOD JB 《QJM : monthly journal of the Association of Physicians》1992,83(3):427-438
In order to describe the British experience of Wegener's granuiomatosisHospital Activity Analysis was used to collect cases diagnosedin England, Wales and Scotland between 1975 and 1985. Wherepossible clinical details, histological material and chest radiographswere obtained. Two hundred and sixty five patients were consideredto have Wegener's granuiomatosis. In 109 a single pathologistconfirmed the diagnosis by finding both granulomas and vasculitisin biopsy material. The diagnosis was made on clinical groundsor clinical grounds together with histological diagnosis inthe local hospital in 156 patients. Wegener's granuiomatosiswas confined to the lung or upper respiratory tract in 22 percent of patients and renal disease occurred in 58 per cent.Laboratory tests showed a pattern of mild anaemia, polymorphleucocytosis, eosinophilia and an elevated ESR and hypergammaglobulinaemia,with no specific pattern of changes. Histological confirmation was most frequently obtained by examinationof nasal biopsy specimens, but multiple biopsies were oftenrequired. Renal biopsies showed focal proliferative glomerulonephritisbut granulomatous glomerulonephritis was uncommon. Of availablechest radiographs 61 per cent were abnormal, large opacitiesbeing most common. Small irregular opacities were found lessoften and other abnormalities were uncommon. Treatment varied widely and 10 per cent of patients receivedno drug therapy. This large series illustrates that even withoutspecific treatment, patients with Wegener's granuiomatosis cansurvive for several years and with modern treatment survivalfor more than a decade is possible. Conclusions about the effectivenessof the various therapies cannot be drawn from this restrospectivestudy. Renal failure and disseminated vasculities were the commonestcauses of death; death was considered to result from complicationsof treatment with cytotoxic drugs or prednisolone in 6 per centof patients. 相似文献
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Polycystic Kidney Disease Re-evaluated: A Population-based Study 总被引:2,自引:0,他引:2
DAVIES F; COLES GA; HARPER PS; WILLIAMS AJ; EVANS C; COCHLIN D 《QJM : monthly journal of the Association of Physicians》1991,79(3):477-485
A genetic register of all known cases of autosomal dominantpolycystic kidney disease occurring in South and Mid-Wales hasbeen established. In a population of 2.1 million, 209 familieswith affected members were identified, 303 of whom are currentlyalive, 70 on renal replacement therapy. An additional 551 caseswould be predicted amongst family members at 50 per cent and25 per cent risk, giving an apparent prevalence of 1:2459 inthe general population. Five possible new mutations were seenwhere adults with phenotypic autosomal dominant polycystic kidneydisease had both parents alive, age > 55 years with no cystsvisible on ultrasound. The take-on rate for renal replacementtherapy increased during 197079 but has apparently reacheda plateau of 4.8 cases per million population per year overthe last 8 years, despite a rapidly increasing acceptance ofuraemic patients as a whole (72/106/year in 198889).Considerably more patients with autosomal dominant polycystickidney disease aged over 50 years were started on treatmentin 198089 than in 197079, but the survival overallimproved with time. All cases of autosomal dominant polycystickidney disease reaching end-stage renal disease are now beingtreated, but the apparent clinical prevalence of this conditionin our region is less than half the supposed gene frequency,suggesting that undiagnosed cases have a benign prognosis. 相似文献
18.
YASUFUMI IMANAKA † KALPANA LAL TAKUYA NISHIMURA † PAULA H. B. BOLTON-MAGGS EDWARD G. D. TITDDENHAM JOHN H. MCVEY 《British journal of haematology》1995,90(4):916-920
Summary. We have studied two heterozygous unrelated CRM non-Jewish FXI-deficient patients. Neither of the patients carries a previously described mutation. Their FXI genes were screened by SSCP analysis following PCR amplification of each exon and the flanking intronic sequences. DNA fragments showing aberrant mobility were cloned and sequenced. The following mutations were identified: in case 1, a T to G transition in exon 12 results in the substitution of Phe-442 by Val (FXI-F442V); in case 2 a C to A transition in exon 5 results in the substitution of Cys-128 by a nonsense codon (FXI-C128X). The missense mutation results in a substitution within the protease domain of FXI. Molecular modelling locates this residue in a structurally conserved region of the protease domain and the amino acid substitution may therefore interfere with either chain folding and subsequent secretion or the stability of the protein in plasma. We conclude that the mutations which we have identified are responsible for the inherited abnormality in these patients. 相似文献
19.
Developmental trends in children''s pretend play 总被引:1,自引:0,他引:1
PAULA LYYTINEN 《Child: care, health and development》1991,17(1):9-25
The developmental trends in pretend play were investigated in children 2-6 years of age (18 in each of five age groups) by examining changes in pretend action and speech separately. Play behaviour was assessed by using a selected set of Duplo Lego toys. Interest focused on occurrence of decentration, decontextualization and integration at different age levels. The proportions of decentred and decontextualized acts, action integrations and play themes, increased linearly with age. Changes in substitutive and inventive actions were, however, more minor than expected. Single-scheme combinations did not reveal any essential aspect of the development of children's symbolic competence. In this sense, multischeme combinations were more important in revealing the children's way of organizing toy material. Linear age trends were not found for language measures. The use of decentred utterances, language integrations and linguistically expressed themes were individual-specific rather than age-related. Issues for studying pretend play in language-impaired groups are also suggested. 相似文献
20.
SUMMARY Hypnotic medication reliably improves sleep during the day, in terms of increasing total sleep time (TST) and reducing awakenings and light sleep. Middle-aged individuals may benefit more than young adults. In addition, the time of day during which sleep is attempted may influence the efficacious dose of short-acting drugs. Available data suggest that improving sleep during the day may improve alertness/performance at night to a mild degree, but significant circadian-related sleepiness remains. Hypnotic medication may help minimize the cumulative effects of sleep loss associated with daytime sleep. Use for more than one week has not been adequately studied; however, as most night and rotating workers' schedules allow for night-time sleep for two or more nights per week, available evidence indicates that hypnotics can be used effectively on an intermittent basis, e.g. for the first 2–4 day-sleep periods of night shifts. Caffeine has been shown to increase alertness and improve psychomotor performance during usual night-shift hours when taken between 22.30 and 01.20 hours. Available data indicate that at approximate dosages of 250–400 mg, the beneficial effects persist until at least 05.30 hours. For most subjects, caffeine taken at the start of the night-shift does not interfere significantly with daytime sleep beginning at 09.00 hours. There is also some evidence that single doses of caffeine at the beginning of a night shift may be more alerting than divided doses. If caffeine is to be used therapeutically, avoidance of social use may be required to avoid tolerance to CNS stimulant effects. Despite the positive results of laboratory research examining hypnotics or caffeine as shiftwork countermeasures, field trials have not been conducted. 相似文献