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101.
During computed tomography (CT) pelvimetry of two pregnant women, bony abnormalities of the fetuses were noted on the scout images that were not confirmed at delivery. To explore the cause of these artifacts, specimen long bones were manipulated in various ways during CT scout imaging. Artifacts like those seen during in vivo imaging were found to be caused by motion of the object. The CT scout view is an example of an image produced by a digital system that uses a scanning beam. This type of digital system is being used for several types of body imaging including screening for scoliosis and chest radiography. Attention to motion artifacts should decrease diagnostic errors and aid further development of these systems. 相似文献
102.
A gene recently inactivated in human defines a new olfactory receptor family in mammals 总被引:6,自引:3,他引:3
Rouquier S; Friedman C; Delettre C; van den Engh G; Blancher A; Crouau-Roy B; Trask BJ; Giorgi D 《Human molecular genetics》1998,7(9):1337-1345
The olfactory receptor (OR) gene family constitutes one of the largest
multigene families and is distributed among many chromosomal sites in the
human genome. Four OR families have been defined in mammals. We previously
demonstrated that a high fraction of human OR sequences have incurred
deleterious mutations, thus reducing the repertoire of functional OR genes.
In this study, we have characterized a new OR gene, 912-93, in primates.
This gene is unique and it defines a new OR family. It localizes to human
chromosome 11q11-12 and at syntenical sites in other hominoids. The
sequence marks a previously unrecognized rearrangement of pericentromeric
material from chromosome 11 to the centromeric region of gibbon chromosome
5. The human gene contains a nonsense point mutation in the region
corresponding to the extracellular N-terminus of the receptor. This
mutation is present in humans of various ethnic groups, but is absent in
apes, suggesting that it probably appeared during the divergence of humans
from other apes, <4 000 000-5 000 000 years ago. A second mutation, a
frameshift at a different location, has occurred in the gorilla copy of
this gene. These observations suggest that OR 912-93 has been recently
silenced in human and gorilla, adding to a pool of OR pseudogenes whose
growth may parallel a reduction in the sense of smell in primates.
相似文献
103.
Normal acetabular anatomy for acetabular fracture assessment: CT and plain film correlation 总被引:3,自引:0,他引:3
The computed tomographic (CT) and conventional radiographic appearances of the acetabulum are correlated for assessment of acetabular fractures according to the Judet and Letournel classification system, a system widely used by orthopedic surgeons performing fracture reduction and external fixation of the acetabulum. A desiccated pelvis was marked along the acetabular borders with lead solder, and anteroposterior (AP) and oblique radiographs were obtained. The solder was then replaced by barium-impregnated string, and the acetabulum was scanned by CT. Radiographic-CT correlations of acetabular landmarks should aid the orthopedist by providing a useful interpretation of acetabular fractures according to the Judet and Letournel system. 相似文献
104.
105.
J De Schepper BJ Otten I François J-P Bourguignon M Craen I Van der Burgt GG Massa 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(9):943-946
We studied the growth-promoting effect of treatment with recombinant human growth hormone in 23 prepubertal children with Noonan syndrome, aged between 5. 4 and 14. 3 y, and all with a height < 1. 4 SD for Tanner standards. The growth response and skeletal maturation after 1 y of recombinant human growth hormone treatment (0. 15 U/kg/day given by daily injection) in the Noonan syndrome patients was compared with the auxological changes observed in a group of 17 girls with Turner syndrome with a comparable age and height deficit who were treated with recombinant human growth hormone in a similar way. During 1 y of treatment, the mean ± SD height velocity increased by 4. 0 ± 1. 6 cm/y in the Noonan syndrome group and by 3. 6 ± 1. 3 cm/y in the Turner syndrome group. Height SDS for chronological age in the Noonan syndrome group increased by 0. 53 ± 0. 46 ( p < 0. 001). In the Noonan syndrome patients the changes in height velocity were positively related to birthweight ( r = 0. 48, p < 0. 05). The changes in height velocity or height SDS were not related to the age, height deficit or a delay in bone age maturation at start of treatment. In neither the patients with Noonan syndrome nor Turner syndrome was an acceleration of bone maturation found. We conclude that treatment with recombinant human growth hormone in pre-pubertal NS patients induces an increase in height velocity and height SDS comparable to that observed in Turner syndrome girls. 相似文献
106.
A 64 year old caucasian male with known alcoholic liver disease presented with rectal bleeding. The patient bled repeatedly despite resuscitation. A sigmoid colectomy was performed following an angiogram. Large colonic, rectal and mesenteric variceal vessels were noted at surgery. Further bleeding postoperatively was rapidly controlled with octreotide infusion. Octreotide may be as useful in the control of colonic variceal bleeding as it is in the control of oesophageal variceal bleeding. 相似文献
107.
An assay was standardized to measure extrinsic pathway inhibitor (EPI) activity in human plasma. Variables that could potentially influence its measurement were systematically examined. The coefficient of variation of the assay was 6.3% for the same sample assayed on different days. The linear regression line for a plot of observed v expected values of mixtures of plasmas with different EPI levels was Y = 1.01X - 2.7%. Single samples from 21 healthy adults under 60 years of age varied between 74% and 159% of a pooled reference plasma. The plasma level of a given individual (eight subjects) did not vary on repeat sampling over weeks to months. EPI activity was significantly lower in plasma from umbilical cord blood (64.3% +/- 12.7%, n = 16) than in plasma from adults. Mean EPI activity in adults greater than or equal to 60 years of age was slightly but significantly higher (112% +/- 16.8%, n = 23) than in adults less than 60 years of age (97.2% +/- 19.0%, n = 21). EPI levels in the third trimester of pregnancy were slightly higher than in nonpregnant women. Plasma EPI levels fell slightly after surgical procedures that caused fibrinogen levels to rise, which suggests that EPI is not an acute phase reactant. Administration of 1-desamino-8-d-arginine vasopressin (DDAVP) did not alter plasma EPI levels. In two patients subjected to plasmapheresis and volume replacement with albumin and isotonic saline, plasma EPI levels returned to one-half of the levels before pheresis within about one day. 相似文献
108.
Spatial variation of T2 in human articular cartilage 总被引:20,自引:0,他引:20
109.
There is considerable anecdotal evidence that where a coherent, consistent
and concise message, coupled with an active and resilient lobby campaign
has been taken to a health authority and local MPs, funding has followed.
The key feature of these efforts has been clinicians and patients working
together. Also, campaigns are the more successful with the more patients
that can be involved and this is an area where clinicians could play a
major role in motivating patients to apply pressure on health authorities.
Many infertility specialists and other professional colleagues have been
very active in arguing the case both on their own account and when backing
the work of the National Infertility Awareness Campaign and patients
generally. Others have not. For them, this article is their call to arms.
相似文献
110.
EA Mitchell BJ Taylor RP Ford AW Stewart DM Becroft JM Thompson R Scragg IB Hassall DM Barry EM Allen 《Archives of disease in childhood》1993,68(4):501-504
The association between dummy use and sudden infant death syndrome (SIDS) was investigated in 485 deaths due to SIDS in the postneonatal age group and compared with 1800 control infants. Parental interviews were completed in 87% of subjects. The prevalence of dummy use in New Zealand is low and varies within New Zealand. Dummy use in the two week period before death was less in cases of SIDS than in the last two weeks for controls (odds ratio (OR) 0.76, 95% confidence interval (CI) 0.57 to 1.02). Use of a dummy in the last sleep for cases of SIDS or in the nominated sleep for controls was significantly less in cases than controls (OR 0.44, 95% CI 0.26 to 0.73). The OR changed very little after controlling for a wide range of potential confounders. It is concluded that dummy use may protect against SIDS, but this observation needs to be repeated before dummies can be recommended for this purpose. If dummy sucking is protective then it is one of several factors that may explain the higher mortality from SIDS in New Zealand than in other countries, and may also explain in part the regional variation within New Zealand. 相似文献