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341.
342.
海风藤的原植物——腺鳞蒟与山药的比较研究 总被引:1,自引:0,他引:1
本文对模式产地的山药Piper haneei Maxim, var, hancei Maxim,和腺鳞蒟P. kancei Maxim var. squamiglanduferum Fan var. nov.进行了原植物形态特征和花序轴、花序梗、茎、叶的显微特征以及化学成分的TLC及UV比较。挥发油的GC—MS研究共鉴定出38个成分,其中28个是胡椒属植物中首次报道的成分。结果证明了在福建长期以来被认为是山药的腺鳞蒟与模式产地的山药有较大差别,尤其是腺鳞蒟叶上表面有腺鳞,是迄今为止第1个发现具有腺鳞的胡椒属植物。据此把腺鳞蒟作为新变种从山药中分出。腺鳞药是福建南部海风藤主要来源之一。 相似文献
343.
The pulsed-injection method for measuring the velocity of blood flow in intraarterial digital subtraction angiography is described. With this technique, contrast material is injected at a pulsing frequency as high as 15 Hz, so that two or more boluses can be imaged simultaneously. The velocity of flow is determined by measuring the spacing between the boluses and multiplying it by the pulsing frequency. Results of tests with phantoms correlate well with flow measurements obtained with a graduated cylinder for velocities ranging from 8 to 60 cm/sec. The potential of the method for time-dependent velocity measurement has been demonstrated with simulated pulsatile flows. 相似文献
344.
The receptors for granulocyte-macrophage colony-stimulating factor (GM- CSF) and interleukin-3 and -5 (IL-3, IL-5) share a common signaling subunit (beta c). However, in the mouse, IL-3 can also use an alternative IL-3-specific receptor beta-chain (beta IL-3). To assess the relative contributions of beta c and beta IL-3 to IL-3 receptor formation and function, mice were generated in which the beta IL-3 gene was functionally inactivated by replacement of exons 9-13 with a neomycin resistance cassette. Bone marrow cells from these mice displayed a lower affinity IL-3 receptor than normal and were hyporesponsive to IL-3, but the mice displayed no obvious hematopoietic abnormalities. The data suggested that beta c and beta IL-3 are normally coexpressed on IL-3-responsive cells and have identical qualitative signaling capacities. Receptor transmodulation studies on bone marrow cells from wild-type, beta c -/-, and beta IL-3 -/- mice showed that the previously described hierarchical pattern of transmodulation was dependent on the relative numbers of both beta IL-3 and beta c receptor chains and also provided evidence for an unexpected interaction between beta c chains and G-CSF and M-CSF receptors. 相似文献
345.
The International Association for the Study of Pain, has defined pain as “an unpleasant sensory and emotional experience connected with actual or potential tissue damage or described in terms of such damage”. It was thought that the newborn baby does not experience pain because of incompletely developed nervous system. However, it has been shown that neurological system known to be associated with pain transmission and modulation, is intact and functional. A study was conducted in our center to study the analgesic effect of administration of oral glucose in various concentrations, in neonates undergoing heel punctures, for collection of blood for investigations. This was compared with the analgesic effects of breast milk (which contains lactose). 125 full term normal neonates with no history of birth asphyxia or underlying neurological abnormality, requiring heel punctures for collection of blood for various investigations were selected for the study. They were matched for gestational age, birth weight and sex distribution and divided into 5 groups of 25 each. One group comprised control subjects and was administered sterile water. 3 groups were administered 1 ml of varying strengths of glucose solutions i.e. 10%, 25% and 50% respectively. The last group was given 1 ml of expressed breast milk (EBM). Prior to heel pricks, state of arousal, baseline heart rate (HR) and transcutaneous oxygen saturation (SpO2) were recorded by pulse oximeter in each neonate. Autolet, a mechanical device for capillary sampling, was used for heel pricks to give equal strength of painful stimulus in each procedure. Audio tape recorder was used to record the cry. The oral solution was administered slowly over 30 seconds by means of a syringe placed in the mouth. Heel puncture was done after 2 minutes, taking all aseptic precautions. HR and SpO2 were monitored using pulse oximeter. Pain response was assessed, by recording duration of crying, change in HR, change in SpO2 and facial action score after the procedure. Mean duration of cry and total cry over 5 minutes was significantly less in groups given 25% and 50% glucose solutions as compared to the control group and babies given EBM. Difference in mean increase in HR, fall in SpO2 were statistically significant between control group, EBM group and neonates given 25% and 50% glucose solutions respectively. Compared to control group, all other administered solutions (10%, 25%, 50% glucose and EBM) were found to reduce physiological and behavioral responses in neonates undergoing heel punctures. 25% and 50% glucose solutions were found to have maximal analgesic effect and both were found to be equally effective. EBM and 10% glucose solution have an equal analgesic effect but less than 25% or 50% glucose. This simple, cheap and safe method of oral analgesia can be easily used in neonates undergoing heel prick procedures during routine neonatal care.Key Words: Analgesic effect, Breast milk, Glucose, Neonates 相似文献
346.
Penetrating eye injuries in rural New South Wales 总被引:1,自引:0,他引:1
CG Thompson MB BS DipObs RKS Griffits FRACO W Nardi FRACO MP Tester FRACO MJ Noble FRCOphth L Cottee FRACO P Weir FRACO 《Clinical & experimental ophthalmology》1997,25(1):37-41
Purpose: To determine the epidemiology and outcomes of penetrating eye injuries in a rural Australian setting. Methods: A retrospective study of an 11 year period to identify 77 cases of penetrating eye injury in Lismore, New South Wales. Results: The commonest cause of penetrating eye injury was fencing wire followed by hammering metal. The average age was 32.6 years, and males were involved in 88% of cases. A final visual acuity of 6/12 or better was achieved in 61% of cases. Enucleation was performed in 14%. Visual outcome was best for wounds involving the cornea only. Conclusions: Penetrating eye injuries are potentially devastating to vision, but with modern surgical techniques patients are likely to achieve reasonable vision. Prevention requires education to ensure adequate protective measures are taken in potentially hazardous settings. 相似文献
347.
348.
Jones CH; Newstead CG; Wills EJ; Davison AM 《Nephrology, dialysis, transplantation》1997,12(3):554-558
HYPOTHESIS: Trends in serum albumin concentration over time provide a
better prediction of clinical outcome in CAPD patients than a single mean
value. METHODS: This was a retrospective review of outcome at 36 months in
225 adult CAPD patients. Mean serum albumin was determined for the first
(SA1) and second (SA2) 6 months of treatment and patients grouped according
to SA1 (group I, > 37; group II, 34-37; group III, < 34 g/l) and
according to the change in serum albumin (delta SA) between the first and
second 6 months (increased/static or decreased). Patient (PS) and technique
(TS) survival were determined by Kaplan-Meier survival analysis. The effect
of SA1 and delta SA on survival were determined in a multivariate Cox
regression analysis model that included age and presence or absence of a
systemic disease. RESULTS: By SA1 group, PS and TS survival at 36 months
were 94 and 76% (group I), 64 and 53% (group II) and 70 and 52% (group
III). If delta SA increased/remained static, then SA1 did not predict PS
(group I, 100%; group II, 96%; group III, 74%; P = n.s.) or TS (group I,
72%; group II, 63%; group III, 65%; P = n.s.). If delta SA decreased, PS
was worse in groups II and III, both as compared to group I (PS group I,
88%; group II, 52%; group III, 34%; P = 0.02) and as compared to the groups
II and III when delta SA increased (PS group II, 74 vs 52%, P = 0.05; group
III, 82 vs 34%, P = 0.005) The same trend was seen for TS. In the
multivariate Cox regression model, age, direction of change in serum
albumin, and presence of a multisystem disease were significant predictors
of survival, whereas SA1 was not. CONCLUSION: Early hypoalbuminaemia in
CAPD only predicts a worse patient and technique survival if mean serum
albumin decreases further from the first to second 6 months of dialysis
therapy. Change in serum albumin between the first and second 6 months of
CAPD and the mean serum albumin over the first 6 months together offer
better discrimination of outcome than either alone.
相似文献
349.
An automated enzymatic method for measurement of D-arabinitol, a metabolite of pathogenic Candida species. 总被引:7,自引:2,他引:5
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A C Switchenko C G Miyada T C Goodman T J Walsh B Wong M J Becker E F Ullman 《Journal of clinical microbiology》1994,32(1):92-97
An automated enzymatic method was developed for the measurement of D-arabinitol in human serum. The assay is based on a novel, highly specific D-arabinitol dehydrogenase from Candida tropicalis. This enzyme catalyzes the oxidation of D-arabinitol to D-ribulose and the concomitant reduction of NAD+ to NADH. The NADH produced is used in a second reaction to reduce p-iodonitrotetrazolium violet (INT) to INT-formazan, which is measured spectrophotometrically. The entire reaction sequence can be performed automatically on a COBAS MIRA-S clinical chemistry analyzer (Roche Diagnostic Systems, Inc., Montclair, N.J.). Replicate analyses of human sera supplemented with D-arabinitol over a concentration range of 0 to 40 microM demonstrated that the pentitol could be measured with an accuracy of +/- 7% and a precision (standard deviation) of +/- 0.4 microM. Serum D-arabinitol measurements correlated with those determined by gas chromatography (r = 0.94). The enzymatic method is unaffected by L-arabinitol, D-mannitol, or other polyols commonly found in human serum. Any of 17 therapeutic drugs potentially present in serum did not significantly influence assay performance. Data illustrating the application of the assay in patients for possible diagnosis of invasive candidiasis and the monitoring of therapeutic intervention are presented. The automated assay described here was developed to facilitate the investigation of D-arabinitol as a serum marker for invasive Candida infections. 相似文献
350.
Kushner DC; Cleveland RH; Herman TE; McLoud TC; Waltman AC; Shepard JA; Dedrick CG; Kopans DB; Greene RE 《Radiology》1987,163(3):685-688
Standard film examinations of the chest were compared with low-dose flying spot digital radiographic examinations obtained with a prototype unit in 174 patients. Analysis of pooled data from a double-blind study of 120 patients showed that film was more sensitive than digital images in the detection of pulmonary parenchymal abnormalities, that is, abnormal opacities, atelectasis, scar, and interstitial lung disease (P less than .05). Analysis of pooled data from a side-by-side study of 54 patients showed that the digital images were more sensitive than film in the detection of normal mediastinal and pleural soft-tissue contours, including the azygoesophageal recess, paraspinal line, and vertebral disk spaces (P less than .05). However, film was more sensitive than digital images in the detection of abnormalities of the lung, including scar, interstitial lung disease, septal lines, and the presence of vascular catheters (P less than .05). These findings suggest that low-dose flying spot digital radiography of the chest, as performed with this specific prototype unit, is not adequate to replace film in the detection of abnormalities of the lung parenchyma. 相似文献