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81.
Lateralisation of a variety of visual functions: food discrimination, fear response, copulation, and performance of topographical and other tasks, such as olfactory and auditory functions, have been described in the domestic chick, Gallus gallus domesticus. A bias to left hemisphere control on day 8 and to the right on day 11 has also been demonstrated in the domestic chick. In this study we show that motor control as to foot preference in initiating a scratching bout and a tape-removing task is lateralised in both adults and chicks. There was a preference for the right leg to initiate a bout of ground scratching in both male and female adult birds. Second, foot preference is also affected by the changes in shifts of bias on day 8 and day 11. The right leg preference in initiating a ground scratching bout observed on day 5 is reversed to a left leg preference on day 8. This then reverts to the right leg preference after day 11. Hence it is postulated that the hemisphere that is not activated due to the bias of age controls the first leg to be used in initiating routine movements such as ground scratching. For the tape-removing task the right leg was used to remove a tape adhered to the beak of the chick for the trained group on day 8; but there was no preference in the naive group. Similarly, on day 11 a left foot bias was observed for the trained group and right foot bias for the naive group. To remove a tape the activated hemisphere on days of bias is used; whereas in a novel situation the foot use is reversed. Thus, footedness is affected by age, type of task, and changing hemispheric dominance. 相似文献
82.
83.
The kinetics of deregulation of expression by de novo methylation of the h19 imprinting control region in cancer cells 总被引:4,自引:0,他引:4
Epigenetic lesions are common in neoplasia and range from hypermethylation of subsets of CpG islands to loss of imprinting. By exploiting an episomal model system and the strong de novo methylation capacity of a human cancer cell line, we show that an H19 minigene rapidly becomes methylated and silenced, mimicking the inactivation of the maternal H19 allele in a range of cancers. Although the H19 imprinting control region (ICR) initially displayed methylation protection, it eventually succumbed to the pressure mounted by the de novo methylation machinery of the JEG-3 cells. Importantly, we were able to visualize the kinetics of the loss of the H19 ICR chromatin insulator function in association with chromatin compaction. Our results document that a strong de novo methylation machinery leads to loss of methylation privilege states of H19 ICR to functionally manifest loss of insulator function in a matter of only a few days in human cancer cells. 相似文献
84.
Impaired gastrointestinal motility as a result of interruption of sympathetic outflow is a common occurrence in the spinal cord injury (SCI) population. In addition, frequent use of medications with anticholinergic properties in this population results in further impairment of peristalsis resulting in gastrointestinal stasis. Since SCI patients often lack sensation below the level of injury, they may present with vague symptoms, which complicates the diagnosis of intestinal obstruction. We report the first case of gastric phytobezoar in a patient with T4 ASIA A paraplegia who presented with vague upper abdominal discomfort, anorexia, weight loss, and vomiting. Because mortality rates can be as high as 30% if phytobezoars remain untreated, gastrointestinal phytobezoars should be considered in the differential diagnosis of abdominal discomfort in SCI patients. Etiologic factors for phytobezoars are discussed for the general population and in particular, for patients with SCI. 相似文献
85.
86.
A. K. Gupta Sunanda Gupta Dharam S. Meena Umadatt Sharma 《Indian journal of otolaryngology and head and neck surgery》2002,54(2):136-139
Sixty patients aged 15 to 40 years of either sex, American Society of Anaesthesiologists (ASA) grade I and II, undergoing tonsillectomy, were randomly allocated to receive either preroperative intramuscular diclofenac sodium(group A) or pre- incisional bilateral infiltration of bupivacaine in the peritonsillar fossa (group B) or post operative Trunscutaneous Electric Nerve Stimulation - TENS (group C) at fixed time intervals. Pain scores (Visual analogue scale VAS, 0- 100 mm) were assessed at rest and on deglutition at 1,3,6,9,12 and 24 hours after surgery. Pentazocine 1actale 15 mg IV was given as rescue analgesic whenever VAS estimation was more than 30 mm at rest (not deglutition). Constant incisional pain was significantly less ( p < 0.01 ANOVA) in group C after 3 hours of surgery as compared to group A and B. Similarly pain on deglutition was significantly less (p <0.01, ANOVA) in group C during the entire study period as compared to Group A and B. There was significant reduction of VAS (p< 0.01) immediately after TENS therapy at 0, 4 and 8 hours. Rescue analgesic consumption was significantly lower in TENS group. Thus, TENS seems to be an effective therapeutic modality for post tonsillectomy pain relief as compared to the other two methods. 相似文献
87.
Ruggieri M D'Arrigo G Abbate M Distefano A Upadhyaya M 《European journal of pediatrics》2000,159(7):477-480
A number of frequently unrecognised vascular manifestations have been described in patients with neurofibromatosis type 1
(NF1), including involvement of the great vessels, cerebral, visceral and renal arteries. Rarely, changes in the coronary
arteries have been reported in adults with NF1. We report on a 16-year-old boy affected by NF1 with dysmorphic features and
three aneurysms in the mid-portion of the left descending coronary artery disclosed by chance during investigation for a malignant
peripheral nerve sheath tumour. Molecular analysis detected a gross de novo deletion in the NF1 gene. The boy had had no previous
cardiac symptoms but died suddenly after developing signs and symptoms suggestive of myocardial infarction.
Conclusion To the best of our knowledge, this represents the first report of multiple lesions in the coronary arteries in a child affected
by neurofibromatosis type 1 with a known deletion of the neurofibromatosis type 1 gene.
Received: 11 November 1999 and in revised form: 9 January 2000 / Accepted: 9 January 2000 相似文献
88.
GL BONACRUZ JD ARNOLD GI LESLIE L. WYNDHAM G. KOUMANTAKIS 《Journal of paediatrics and child health》1996,32(4):299-301
Objective : To determine the approach to identifying neonatal hypoglycaemia and the definition of neonatal hypoglycaemia used by neonatal paediatricians in Australian Level 3 neonatal intensive care units (NICU).
Methodology : A questionnaire was sent to the 101 neonatal paediatricians in the 22 Level 3 NICU in Australia asking their method of screening for, and definition of, neonatal hypoglycaemia.
Results : Responses were received from 70 neonatal paediatricians, including all 22 directors. A bedside glucose meter is used in 19 of 22 NICU to screen for hypoglycaemia, whilst one NICU uses a glucose analyzer and another NICU uses a visual colour comparison method. One NICU does not screen, but has blood glucose measured in a satellite laboratory. If the screening method suggests hypoglycaemia, 62 of 63 neonatal paediatricians proceed to blood glucose determination in a laboratory, mostly using plasma samples. Based on the laboratory measurement, the definition of neonatal hypoglycaemia ranged from <1.1 to 3.0 mmol/L.
Conclusions : The majority of neonatal paediatricians in Australian NICU screen for neonatal hypoglycaemia using a bedside glucose meter. There is a wide range in the definition of neonatal hypoglycaemia from <1.1 to 3.0mmol/L. 相似文献
Methodology : A questionnaire was sent to the 101 neonatal paediatricians in the 22 Level 3 NICU in Australia asking their method of screening for, and definition of, neonatal hypoglycaemia.
Results : Responses were received from 70 neonatal paediatricians, including all 22 directors. A bedside glucose meter is used in 19 of 22 NICU to screen for hypoglycaemia, whilst one NICU uses a glucose analyzer and another NICU uses a visual colour comparison method. One NICU does not screen, but has blood glucose measured in a satellite laboratory. If the screening method suggests hypoglycaemia, 62 of 63 neonatal paediatricians proceed to blood glucose determination in a laboratory, mostly using plasma samples. Based on the laboratory measurement, the definition of neonatal hypoglycaemia ranged from <1.1 to 3.0 mmol/L.
Conclusions : The majority of neonatal paediatricians in Australian NICU screen for neonatal hypoglycaemia using a bedside glucose meter. There is a wide range in the definition of neonatal hypoglycaemia from <1.1 to 3.0mmol/L. 相似文献
89.
The original article to which this Erratum refers was published in Phytotherapy Research 14(5) 2000, 344-346. Following the publication of this paper in the August 2000 issue of Phytotherapy Research (14(5):344-346), it has come to our attention that there is a misleading statement regarding conclusions cited from the work of Butterweck et al. 1998. The discussion in the recent PTR paper states that those authors are 'in favour of the hypothesis that the antidepressant activity is due to the hypericin only'. We wish to make it clear that this is not the case, and the Butterweck paper actually concludes that 'both naphthodianthrones must be considered as active constituents of the crude extract of H. perforatum. However, previous studies indicate that the other consitutuents of the crude drug also have activity'. The authors apologize for this error and are happy to correct it. 相似文献
90.
ANTEROVENTRAL WALL OF THE THIRD VENTRICLE AND DORSAL LAMINA TERMINALIS: HEADQUARTERS FOR CONTROL OF BODY FLUID HOMEOSTASIS? 总被引:3,自引:0,他引:3
MJ McKinley GL Pennington BJ Oldfield 《Clinical and experimental pharmacology & physiology》1996,23(4):271-281
1. The subfornical organ, median preoptic nucleus and the organum vasculosum of the lamina terminalis (OVLT) are a series of structures situated in the anterior wall of the third ventricle and form the lamina terminalis. The OVLT and ventral part of the median preoptic nucleus are part of a region known as the anteroventral third ventricle region.
2. Data from many laboratories, using techniques ranging from lesions, electrophysiology, neuropharmacology, Fos expression, immunohistochemistry and receptor localization, indicate that the tissue in the lamina terminalis plays a major role in many aspects of body fluid and electrolyte balance.
3. The subfornical organ and OVLT lack the blood-brain barrier and detect alterations in plasma tonicity and the concentrations of circulating hormones such as angiotensin II and possibly atrial natriuretic peptide and relaxin.
4. This information is then integrated within the lamina terminalis (probably in the median preoptic nucleus) with neural signals from other brain regions. The neural output from the lamina terminalis is distributed to a number of effector sites including the paraventricular (both parvo- and magno-cellular parts) and supraoptic nuclei and influences vasopressin secretion, water drinking, salt intake, renin secretion, renal sodium excretion and cardiovascular regulation. 相似文献
2. Data from many laboratories, using techniques ranging from lesions, electrophysiology, neuropharmacology, Fos expression, immunohistochemistry and receptor localization, indicate that the tissue in the lamina terminalis plays a major role in many aspects of body fluid and electrolyte balance.
3. The subfornical organ and OVLT lack the blood-brain barrier and detect alterations in plasma tonicity and the concentrations of circulating hormones such as angiotensin II and possibly atrial natriuretic peptide and relaxin.
4. This information is then integrated within the lamina terminalis (probably in the median preoptic nucleus) with neural signals from other brain regions. The neural output from the lamina terminalis is distributed to a number of effector sites including the paraventricular (both parvo- and magno-cellular parts) and supraoptic nuclei and influences vasopressin secretion, water drinking, salt intake, renin secretion, renal sodium excretion and cardiovascular regulation. 相似文献