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51.
52.
Early transvaginal ultrasound following an accurately dated pregnancy: the importance of finding a yolk sac or fetal heart motion 总被引:1,自引:2,他引:1
Deaton JL; Honore GM; Huffman CS; Bauguess P 《Human reproduction (Oxford, England)》1997,12(12):2820-2823
Our goals were to determine the prognostic value of a yolk sac or fetal
heart motion seen during an early accurately dated transvaginal ultrasound
(TVU). We reviewed 225 consecutive pregnancies for fetal heart motion data.
Furthermore, 63 pregnancies following in-vitro fertilization were reviewed
for yolk sac information. The TVU was performed between 5 and 6 weeks
following presumed conception (heart motion data) and between 22 and 32
days following in-vitro fertilization (yolk sac data). Pregnancies were
followed until an ongoing pregnancy or spontaneous abortion was documented.
The presence of a yolk sac between 22 and 32 days from fertilization was
associated with the development of fetal heart motion in 94% of cases. The
absence of the yolk sac by 32 days after fertilization was always
associated with a poor outcome. In women < 36 years of age, the presence
of fetal heart motion was associated with a spontaneous abortion in only
4.5% of the cases. However, the incidence of spontaneous abortion following
fetal heart motion increased to 10% in women 36-39 years and 29% in women
> or = 40 years of age. The presence of heart motion should not be
considered a reassuring sign in the older woman. These data have
implications regarding early embryology and the counselling of infertility
patients.
相似文献
53.
Dongari-Bagtzoglou AI; Warren WD; Berton MT; Ebersole JL 《International immunology》1997,9(9):1233-1241
CD40, a member of the tumor necrosis factor-alpha receptor family, is
constitutively expressed by cells of hematopoietic and non- hematopoietic
origin, including fibroblasts. Signaling through this receptor molecule
regulates inflammatory cytokine secretion by many cell types. Based on the
recently described cytokine secretory heterogeneity of fibroblast cell
subsets, we hypothesized that secretion of inflammatory cytokines by
gingival fibroblast cultures may be dictated by the existence of
differential proportions of cytokine- secreting subpopulations which
express high levels of CD40. After examining a large number of gingival
fibroblast (GF) cultures we find that the frequency of IL-6- and
IL-8-secreting cells mirrors the frequency of cells expressing high levels
of CD40 in these cultures. In addition, we demonstrate a direct functional
relationship between CD40 expression and IL-6 or IL-8 secretion by showing
that ligation of this molecule on GF, and CD40+ fibroblast subsets in
particular, up- regulates secretion of these cytokines in vitro.
相似文献
54.
55.
Frataxin is reduced in Friedreich ataxia patients and is associated with mitochondrial membranes 总被引:17,自引:8,他引:17
Campuzano V; Montermini L; Lutz Y; Cova L; Hindelang C; Jiralerspong S; Trottier Y; Kish SJ; Faucheux B; Trouillas P; Authier FJ; Durr A; Mandel JL; Vescovi A; Pandolfo M; Koenig M 《Human molecular genetics》1997,6(11):1771-1780
Friedreich ataxia is a progressive neurodegenerative disorder caused by
loss of function mutations in the frataxin gene. In order to unravel
frataxin function we developed monoclonal antibodies raised against
different regions of the protein. These antibodies detect a processed 18
kDa protein in various human and mouse tissues and cell lines that is
severely reduced in Friedreich ataxia patients. By immunocytofluorescence
and immunocytoelectron microscopy we show that frataxin is located in
mitochondria, associated with the mitochondrial membranes and crests.
Analysis of cellular localization of various truncated forms of frataxin
expressed in cultured cells and evidence of removal of an N-terminal
epitope during protein maturation demonstrated that the mitochondrial
targetting sequence is encoded by the first 20 amino acids. Given the
shared clinical features between Friedreich ataxia, vitamin E deficiency
and some mitochondriopathies, our data suggest that a reduction in frataxin
results in oxidative damage.
相似文献
56.
Distribution of mutations in the PEX gene in families with X-linked hypophosphataemic rickets (HYP) 总被引:8,自引:0,他引:8
Rowe PS; Oudet CL; Francis F; Sinding C; Pannetier S; Econs MJ; Strom TM; Meitinger T; Garabedian M; David A; Macher MA; Questiaux E; Popowska E; Pronicka E; Read AP; Mokrzycki A; Glorieux FH; Drezner MK; Hanauer A; Lehrach H; Goulding JN; O'Riordan JL 《Human molecular genetics》1997,6(4):539-549
Mutations in the PEX gene at Xp22.1 (phosphate-regulating gene with
homologies to endopeptidases, on the X-chromosome), are responsible for
X-linked hypophosphataemic rickets (HYP). Homology of PEX to the M13 family
of Zn2+ metallopeptidases which include neprilysin (NEP) as prototype, has
raised important questions regarding PEX function at the molecular level.
The aim of this study was to analyse 99 HYP families for PEX gene
mutations, and to correlate predicted changes in the protein structure with
Zn2+ metallopeptidase gene function. Primers flanking 22 characterised
exons were used to amplify DNA by PCR, and SSCP was then used to screen for
mutations. Deletions, insertions, nonsense mutations, stop codons and
splice mutations occurred in 83% of families screened for in all 22 exons,
and 51% of a separate set of families screened in 17 PEX gene exons.
Missense mutations in four regions of the gene were informative regarding
function, with one mutation in the Zn2+-binding site predicted to alter
substrate enzyme interaction and catalysis. Computer analysis of the
remaining mutations predicted changes in secondary structure,
N-glycosylation, protein phosphorylation and catalytic site molecular
structure. The wide range of mutations that align with regions required for
protease activity in NEP suggests that PEX also functions as a protease,
and may act by processing factor(s) involved in bone mineral metabolism.
相似文献
57.
Parathyroid adenomas in the aortopulmonary window 总被引:3,自引:0,他引:3
58.
Ectodermal dysplasias (EDs) are a group of developmental disorders (more than 100) mainly affecting ectodermal tissues and organs. The X-linked hypohidrotic ED (HED) is the most common form of EDs, involving defects in teeth, sweat glands, and hair. In a few reports, HED has been associated with reduced salivary function. In the present case report, a dramatically reduced salivary fluid and acidic proline rich protein production was identified in a 38-year-old man with HED. Computed tomography was performed, revealing that one submandibular gland and both parotid glands were hypoplastic, whereas the right submandibular gland seemed to be absent. These findings are in line with a general developmental disturbance also involving the salivary glands. As salivary tests are inexpensive and easy to perform, it is suggested to routinely evaluate salivary secretion in persons with HED, to prevent a possible negative impact on oral health. 相似文献
59.
Summary An exact study was made of the middle nasal meatus in 20 anatomical preparations (left and right) from 10 subjects. Some features (the ethmoidal bulla, the uncinate process of the ethmoidal bone, the openings of the maxillary and frontal sinuses) are relatively constant in their arrangement, but very variable in shape and size. An understanding of these structures is now essential for the practice of endonasal microsurgery.
De l'anatomie médicochirurgicale du méat nasal moyen
Résumé Une série de 20 préparations anatomiques gauche et droite sur 10 sujets a permis une observation précise du méat nasal moyen. Certains reliefs: la bulle ethmoïdale, le processus uncinatus, les méats des sinus maxillaire et frontal sont relativement fixes dans leur disposition, mais très variables dans leur forme et leurs dimensions. Leur connaissance est maintenant indispensable à tout praticien exerçant la microchirurgie endonasale.相似文献
60.
Fenghui Ye Richard F Keep Ya Hua Hugh JL Garton Guohua Xi 《Journal of cerebral blood flow and metabolism》2021,41(9):2470
Microthrombi formation in the brain following subarachnoid hemorrhage (SAH) has been recognized and suspected to contribute to cerebral ischemia. A recent study found that ultra-early cerebral micro-thrombosis occured four hours after experimental SAH. The number of thrombotic microvessels correlated with brain-blood barrier disruption and neuronal injury. If acute cerebral micro-thrombi also occur in humans, is it time to develop a therapy with systemic thrombolysis for SAH patients? 相似文献