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991.
992.
Attitudes towards routine human immunodeficiency virus (HIV) screening and fertility treatment in HIV positive patients--a UK survey 总被引:1,自引:0,他引:1
Balet R; Lower AM; Wilson C; Anderson J; Grudzinskas JG 《Human reproduction (Oxford, England)》1998,13(4):1085-1087
Of 70 fertility units licensed by the Human Fertilisation and Embryology
Authority in the UK, 58 responded to a questionnaire regarding attitudes
towards human immunodeficiency virus (HIV) screening and fertility
treatment in HIV positive patients in November 1995. Of these 58 centres,
23 only performed routine screening for HIV for both partners, 24 for
hepatitis B and eight for hepatitis C. In the event of a positive result in
the male, fertility treatment would be offered in the form of donor
insemination (n = 21), intrauterine insemination (IUI) after sperm washing
(n = 21), and in-vitro fertilization (IVF) (n = 1). If the woman was HIV
positive, two centres would offer IUI and three centres IVF. Nine centres
had already provided treatment for couples in whom the male partner was HIV
positive and two centres to HIV positive women.
相似文献
993.
R. Gerlai Simon P. Williams Belinda Cairns Nicholas Van Bruggen Paul Moran A. Shih Ingrid Caras Hans Sauer Heidi S. Phillips John W. Winslow 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,123(1-2):24-35
Gene targeting using homologous recombination in embryonic stem (ES) cells offers unprecedented precision with which one may
manipulate single genes and investigate the in vivo effects of defined mutations in the mouse. Geneticists argue that this
technique abrogates the lack of highly specific pharmacological tools in the study of brain function and behavior. However,
by now it has become clear that gene targeting has some limitations too. One problem is spatial and temporal specificity of
the generated mutation, which may appear in multiple brain regions or even in other organs and may also be present throughout
development, giving rise to complex, secondary phenotypical alterations. This may be a disadvantage in the functional analysis
of a number of genes associated with learning and memory processes. For example, several proteins, including neurotrophins
– cell-adhesion molecules – and protein kinases, that play a significant developmental role have recently been suggested to
be also involved in neural and behavioral plasticity. Knocking out genes of such proteins may lead to developmental alterations
or even embryonic lethality in the mouse, making it difficult to study their function in neural plasticity, learning, and
memory. Therefore, alternative strategies to gene targeting may be needed. Here, we suggest a potentially useful in vivo strategy
based on systemic application of immunoadhesins, genetically engineered fusion proteins possessing the Fc portion of the human
IgG molecule and, for example, a binding domain of a receptor of interest. These proteins are stable in vivo and exhibit high
binding specificity and affinity for the endogenous ligand of the receptor, but lack the ability to signal. Thus, if delivered
to the brain, immunoadhesins may specifically block signalling of the receptor of interest. Using osmotic minipumps, the protein
can be infused in a localized region of the brain for a specified period of time (days or weeks). Thus, the location and timing
of delivery are controlled. Here, we present methodological details of this novel approach and argue that infusion of immunoadhesins
will be useful for studying the role particular receptors play in behavioral and neural plasticity. 相似文献
994.
C Musgrove F J Bolton A M Krypczyk J M Temperley S A Cairns W G Owen D N Hutchinson 《Journal of clinical pathology》1988,41(12):1316-1321
The presence of Campylobacter pylori, histologically diagnosed gastritis, and antibodies to C pylori were determined in a series of 113 patients undergoing endoscopy. Paired biopsy specimens from the fundus, body, and antrum were collected from 59 patients and from the antrum of 54 patients. The presence of C pylori was confirmed by either culture or silver stain in 30 of 59, 31 of 59, and 54 of 103 biopsy specimens from the fundus, body, and antrum, respectively. Of the specimens which contained C pylori 20 of 30 (66%) from the fundus, 25 of 31 (80%) from the body, and 54 (100%) from the antrum showed gastritis. C pylori and gastritis were shown in seven of nine (78.1%) of patients with gastric ulcers and in nine of 11 (82%) of patients with duodenal ulcers. Using an enzyme linked immunosorbent assay (ELISA) technique to detect IgG antibody to C pylori, all patients with histologically diagnosed gastritis and organisms present had titres of greater than or equal to 640; eight of 39 (21%) of patients without gastritis and without organisms gave similar titres. Hence the presence of C pylori was associated with gastritis and with raised titres of IgG antibody. 相似文献
995.
alpha-internexin is present in the pathological inclusions of neuronal intermediate filament inclusion disease 下载免费PDF全文
Cairns NJ Zhukareva V Uryu K Zhang B Bigio E Mackenzie IR Gearing M Duyckaerts C Yokoo H Nakazato Y Jaros E Perry RH Lee VM Trojanowski JQ 《The American journal of pathology》2004,164(6):2153-2161
Neuronal intermediate filament (IF) inclusion disease (NIFID) is a novel neurological disease of early onset with a variable clinical phenotype including frontotemporal dementia, pyramidal, and extrapyramidal signs. Pathologically, in affected areas, there is neuronal loss, astrocytosis, and neuronal intracytoplasmic aggregates of abnormal neuronal IFs that contain neither tau nor alpha-synuclein. Thus, to characterize the neuronal IF protein profile of inclusions in NIFID, immunohistochemistry (IHC) was performed on 10 cases of NIFID, four normal aged controls (NL), and two cases of Alzheimer's disease (AD) using a panel of anti-neuronal IF proteins. Immunoelectron microscopy was performed on selected cases and frozen tissue from the frontal lobe of four cases was used for biochemical studies including sequential extractions and Western blotting. Based on these studies, we report here for the first time that alpha-internexin, a neuronal IF protein, is present within the inclusions of NIFID as are all three neurofilament subunits: heavy, medium, and light. Thus, all class IV neuronal IF proteins are present within the pathological inclusions of this disease. Biochemistry revealed that IF aggregates were soluble in sodium dodecyl sulfate (SDS) and no post-translational modification was detected when compared with Alzheimer's disease or aged control brains. Hence, we conclude that NIFID is characterized by the pathological cytoplasmic aggregation of all class IV neuronal IF proteins in brain. The discovery of alpha-internexin in the cytoplasmic inclusions implicates novel mechanisms of pathogenesis in NIFID and other neurological diseases with pathological accumulations of IFs. 相似文献
996.
997.
998.
999.
Somatic mutations are frequent and increase with age in human kidney epithelial cells 总被引:6,自引:0,他引:6
Martin GM; Ogburn CE; Colgin LM; Gown AM; Edland SD; Monnat RJ Jr 《Human molecular genetics》1996,5(2):215-221
We have used a primary cloning assay to determine the frequency of 6-
thioguanine (TG)-resistant tubular epithelial cells in kidney tissue from
72 human donors ranging in age from 2 to 94 years. The frequency of
TG-resistant mutants ranged from approximately 5 x 10(-5) for donors in the
first decade of life to approximately 2.5 x 10(-4) for donors in the eighth
and later decades of life. Two different statistical analyses indicated
that this increase in mutant frequency is exponential with age. We also
observed a 2-fold higher TG-resistant mutant frequency in nephrectomy
kidneys containing a coincident renal carcinoma. DNA sequence analyses
revealed HPRT gene mutations in each of 14 TG-resistant mutants from seven
unrelated donors. Thirteen of these 14 mutants resulted from independent
mutational events. These results suggest that somatic mutations are common
in renal--and perhaps in other human--epithelia, and thus could play an
important role in the genesis of age-associated disease.
相似文献
1000.