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81.
Di Chiro G; Girton ME; Frank JA; Dietz MJ; Gansow OA; Wright DC; Dwyer AJ 《Radiology》1986,160(1):221-222
Canine cerebrospinal fluid rhinorrhea, which occurs frequently in purebred beagles, was demonstrated in two dogs on magnetic resonance images after cisternal introduction of gadolinium-DTPA dimeglumine. 相似文献
82.
对人流感病毒A/Udorn/72(H_3N_2)株与禽类流感病毒A/Mallard/NY/78/(H_2N_2)重组后的重组株分析表明,仅含禽类病毒的核蛋白(NP)或膜蛋白(M)的RNA片段的重组株,在松鼠猴的呼吸道繁殖是受限制的。另外。仅有禽类的RNAl和NS基因的重组株(Clone 12)在松鼠猴的气管内的繁殖也明显受限制,而只具有其中一个基因的Clone 9, Clone 2, 则限制就不明显。由此表明,禽类流感病毒的NP和M基因在宿主范围的繁殖限制中起主要作用,而RNAI和SN基因的结合,同样起着繁殖受限制作用。 相似文献
83.
The carotid-carotid cervical bypass is one surgical option for symptomatic atherosclerotic lesions of the innominate artery. Controversy exists regarding the necessity of surgically excluding the innominate plaque from the cerebral circuit. A canine study was instituted to characterize the hemodynamic alterations that occur in the right common carotid artery proximal to the bypass graft, termed the critical segment. The direction of flow in the critical segment determines whether emboli originating in the innominate may be propelled cranially despite a patent bypass graft. Six mongrel dogs underwent placement of an autogenous arterial crossover graft as a carotid-carotid bypass. A stenosis of the innominate artery was quantitatively altered, and an electromagnetic flowmeter measured the magnitude and direction of flow in the critical segment at three levels of diameter reduction in the innominate artery. For low-grade stenoses, flow in the critical segment was always prograde. For high-grade stenoses, the flow was always reversed. Stenoses between 57% and 67% yielded flow values of 10 +/- 24 ml/min, and it was in this range that mean flow reversal was found to occur. Even when the mean flow was near zero in the critical segment, flow was not stagnant but oscillated in antegrade and retrograde directions throughout the cardiac cycle. These data indicate that a carotid-carotid bypass causes complete flow reversal in the critical segment when there is high-grade stenosis in the innominate artery. Theoretical analysis of the hemodynamic circuit indicated that arm exercise would augment retrograde flow in the critical segment.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
84.
STEWART AJ; ALLEN JD; ADGEY AAJ 《QJM : monthly journal of the Association of Physicians》1992,85(1):761-769
SUMMARY In 56 patients, frequency analysis of the electrocardiogramof ventricular fibrillation exhibited power spectra with a distinctdominant frequency. The greatest success for resuscitation fromventricular fibrillation is recorded when ventricular fibrillationdevelops after the patient comes under coronary care. Of the41 patients in whom the onset and first 8 s of ventricular fibrillationwere artefact-free the mean dominant frequency of primary ventricularfibrillation (no cardiogenic shock or cardiac failure) in 21patients was 6.2±0.2 Hz, significantly higher than themean dominant frequency of the first 8 s of secondary ventricularfibrillation (cardiogenic shock or heart failure) (4.0±0.2Hz, 20 patients, p =0.0001). In these patients the peak-to-troughamplitude (ECG) of the first 8 s of ventricular fibrillationwas similar in both primary and secondary ventricular fibrillationas was the mean duration of ventricular fibrillation prior tothe first DC shock. There was a significantly lower successrate for resuscitation from secondary ventricular fibrillation(6 of 20 patients) compared with resuscitation from primaryventricular fibrillation (18 of 21 patients, x2 17.8, p=0.001).Of the remaining 15 patients who were collapsed between 3 and20 min before the arrival of the mobile coronary care unit,the dominant frequency of the first 8 s of ventricular fibrillationfell with increased duration of collapse (from 5.5 Hz at 3 minto a mean of 2.1 Hz at 20 min). Four of these 15 patients whosurvived the initial arrest had a mean dominant frequency of5.2±0.3 Hz, which was significantly higher than the meandominant frequency (3.1±0.3 Hz, p<0.01) of the 11patients who were not resuscitated. This study shows that low frequency ventricular fibrillationis indicative of a poor chance of successful resuscitation.Alteration of the frequency may increase resuscitation success. 相似文献
85.
O'Mahony S; Morris AJ; Straiton M; Murray L; MacKenzie JF 《QJM : monthly journal of the Association of Physicians》1996,89(9):685-690
We report our experience with small-bowel push enteroscopy in 50 patients.
The indications for push enteroscopy were: anaemia/occult gastrointestinal
bleeding (22 patients); overt gastrointestinal bleeding (17 patients);
abnormal small-bowel radiology (8 patients) and miscellaneous (3 patients).
In those with undiagnosed gastrointestinal bleeding/anaemia, abnormalities
were detected in 24/39 patients (62%): small bowel arteriovenous
malformations (AVMs) were detected in 19 (49%), and five (13%) had lesions
in the upper gastrointestinal tract. Seventeen patients had heater-probe
ablation therapy of vascular lesions: nine patients had small-intestinal
lesions, four patients gastric lesions, and four patients combined gastric
and small- intestinal lesions. In those with abnormal small-bowel
radiology, abnormalities were detected in 6/8 patients. We conclude that
(i) push enteroscopy can establish a diagnosis in a high proportion of
patients with gastrointestinal bleeding; (ii) heater-probe ablation therapy
of vascular lesions can be performed routinely at the time of enteroscopy;
(iii) a significant proportion of patients (9/50) referred for enteroscopy
with undiagnosed gastrointestinal bleeding have lesions in the
stomach/proximal duodenum missed at diagnostic endoscopy. Push enteroscopy
is a valuable diagnostic and therapeutic endoscopic procedure.
相似文献
86.
87.
目的:基质金属蛋白酶在急性心肌梗死后的心室重构中起着重要作用,但其调节机制目前尚未明确。实验拟通过动物模型的建立及体外细胞培养,观察急性心肌梗死后单个核细胞表面CD147与心肌成纤维细胞基质金属蛋白酶-9 mRNA表达的关系。
方法:实验于2006—08/2007-06在河北省人民医院临床实验中心完成。实验材料:SD大鼠及SD仔鼠(出生1~3d)购自河北医科大学试验动物中心。实验过程中对动物处置符合动物伦理学标准。实验方法:①将30只大鼠随机分为急性心肌梗死组(n=15)和假手术组(n=15),假手术组只过线不结扎。流式细胞分析法检测大鼠术后24h外周血单个核细胞表面CD147表达。②选择SD仔鼠制备心肌成纤维细胞。将单个核细胞与心肌成纤维细胞以细胞数0.5:1,1:1,2:1混合培养24h后,半定量反转录一聚合酶联反应法检测基质金属蛋白酶-9 mRNA表达。当单核细胞与心肌成纤维细胞2:1混合时,加入CD147单克隆抗体1,2,4μL/L,培养24h后检测基质金属蛋白酶-9 mRNA表达。
结果:①急性心肌梗死后外周血单个核细胞表面CD147表达明显增加。②单个核细胞与心肌成纤维细胞混合培养,随着单个核细胞比例的增加,心肌成纤维细胞基质金属蛋白酶-9 mRNA表达增加。③在单个核细胞与心肌成纤维细胞2:1混合培养体系中,随着加入CD147单克隆抗体浓度的增加,基质金属蛋白酶-9 mRNA生成减少。
结论:急性心肌梗死后单个核细胞表面CD147表达明显增加,对心肌成纤维细胞基质金属蛋白酶-9生成起上游调节作用。 相似文献
88.
Impact of an infection consultation service for bacteraemia on clinical management and use of resources 总被引:2,自引:0,他引:2
Nathwani D; Davey P; France AJ; Phillips G; Orange G; Parratt D 《QJM : monthly journal of the Association of Physicians》1996,89(10):789-797
Since 1993, the infection consultation service for bacteraemia has seen 310
patients in the Medical and Surgical Directorates at Ninewells Hospital and
Kings Cross Hospital. A random sample of 100 was audited. Case-notes were
incomplete for five patients, leaving 95 fully-audited patients. Clinical
outcome measures were death from infection, and readmission within 2 weeks
of discharge. Initial treatment was inconsistent with antibiotic policy in
46 patients (48%). Antibiotic treatment was changed in 37 (80%) of these
patients: increased in intensity in 19 (41%) and decreased in 18 (39%).
Changes were also made in 30 (61%) of the 49 patients whose initial
treatment was consistent with sepsis policy-increased in seven (14%) and
decreased in 23 (47%). Median daily antibiotic costs were lowered in
patients whose initial treatment was consistent with sepsis policy (pounds
10.10 vs. pounds 7.28, p = 0.0274). However, in the other patients, savings
were balanced by increases (p = 0.7696). Consultation required one
consultant session per week (3.5 h) and the audit required an additional 16
consultant sessions. Seven patients died, but only one death was directly
related to infection. Six patients were readmitted to hospital within 2
weeks, in three due to recurrence of infection. Changes to treatment were
recommended in the majority of patients, regardless of whether initial
treatment complied with the sepsis policy. The service primarily
redistributed resources rather than reducing costs. A fully audited service
requires considerable consultant time, but we believe such time is well
spent.
相似文献
89.
How much would the safety of blood transfusion be improved by including p24 antigen in the battery of tests? 总被引:1,自引:0,他引:1
BACKGROUND: Because p24 antigen may be detectable during seroconversion, before antibodies, some of the infected blood undetected by antibody screening could be identified through antigen screening. STUDY DESIGN AND METHODS: The potential benefit of antigen screening was evaluated in a simulation model incorporating present knowledge of the time sequence from antigen exposure to antibody development during seroconversion and the incidence of seroconversion among repeat donors. The model was designed so that the results were consistent with the observed rate of antibody-positive blood donations and the CIs of surveys that did not find any antibody-negative/antigen- positive donated blood. RESULTS: In the United States in 1990, the number of expected, undetected, contaminated blood components was estimated at 68; of these 8 to 17 could have been identified by antigen screening, depending on the hypothesis explored. (In 1992, 20 undetected, contaminated blood components were expected according to this model, of which 2 to 5 could have been identified by antigen screening.) In France, the comparable figures were 1 to 4 of 13 in 1990 and 1 to 2 of 7 in 1992. CONCLUSION: The projected benefit must be weighted against possible negative consequences, including 1) an increase in recently infected persons seeking p24 antigen screening at blood banks (assuming this test is not incorporated into screening in non-blood bank settings) and 2) the need for additional quality assurance procedures to avoid operational flaws associated with the increase in the donor screening test battery. In any case, the best way of increasing the safety of blood is improvement in the selection of donors, which can diminish the residual risk of transmission of any viruses. 相似文献
90.
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