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41.
Jun Aoki M.D. Richard P. Moser Jr. LTC MC USA Tuyethoa N. Vinh M.D. 《Skeletal radiology》1989,18(6):427-434
This study reviews the demographic, radiologic, and histologic characteristics of 13 cases of an important primary skeletal neoplasm, giant cell tumor of bone, occurring in an uncommon location, the scapula. that eight of 13 patients presented prior to 20 years of age contrasts significantly with the typical age distribution (between 20–40 years) encountered in giant cell tumors arising in long bones. As it does elsewhere in the skeleton, giant cell tumor of the scapula frequently demonstrates cystic and/or telangiectatic components on histologic examination. The radiologic appearances of giant cell tumor in the scapula and in more typical locations are similar and include: (1) well-defined (geographic) margins, occasionally with a delicate sclerotic rim, (2) prominent trabeculations, (3) expanded bone contour, (4) frequent extension to the subchondral plate, and (5) absence of internal mineralization. Tumor sites within the scapula included: coracoid process, acromion, and body (three cases each); glenoid (two cases); and superior and inferior angles (one case each).The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of the Army, the Department of Defense, or the Uniformed Services University of the Health Sciences. 相似文献
42.
Mario Feola Jan Simoni David Fishman Rue Tran Peter C. Canizaro 《Artificial organs》1989,13(3):209-215
Hemoglobin (Hb) solutions can cause vasoconstriction and activation of intravascular coagulation. Because the endothelium plays a major role in the regulation of vascular tone and hemostasis, a study was conducted of human umbilical vein endothelial cells (EC) incubated with various Hbs. Cell injury was evaluated by electron microscopy and the release of lactic dehydrogenase, H2O2, and procoagulant "tissue factor." Cell reaction was assessed by the measurement of 6-keto-prostaglandin F (PGF)1 alpha (metabolite of prostacyclin) and thromboxane B2 (metabolite of thromboxane A2). Incubation with unmodified bovine hemoglobin for 24 h caused no cell injury and a reaction characterized by 48.4 +/- 8.2% increase in 6-keto-PGF1 alpha production, accompanied by 40.2 +/- 9.4% reduction in thromboxane (Tx)B2 (compared with a control group of EC incubated with saline solution). Incubation with a nonpure Hb solution (Hb plus red blood cell membrane aminophospholipids; a-PLs) caused cell injury with significant release of tissue factor, plus a reaction characterized by 97.5 +/- 12.5% increase in TxB2 production accompanied by 25.3 +/- 3% reduction in 6-keto-PGF1 alpha. A second nonpure Hb [Hb plus bacterial environmental endotoxin (E)] caused cell injury, the release of tissue factor, and increased production of both prostaglandins, with greater release of TxB2 (197 +/- 17%) than of 6-keto-PGF1 alpha (112 +/- 8.3%). These data indicate that the endothelium reacts differently to pure and nonpure hemoglobins. The biocompatibility of Hb solutions, with regard to vasoconstriction and activation of intravascular coagulation, depends on the absence of stromal a-PLs and bacterial E. 相似文献
43.
Verschuren MC; Blom B; Bogers AJ; Spits H; van Dongen JJ 《International immunology》1998,10(12):1873-1880
Recombination of deltaRec to psiJalpha will delete the TCR delta gene,
which is thought to play an important role in the bifurcation of the TCR
alphabeta versus TCR gammadelta differentiation lineages. We recently
detected a DNA-binding protein in human thymocytes, the so- called PJA-BP,
which recognizes the psiJalpha gene segment and might be one of the factors
involved in the regulation of preferential deltaRec- psiJalpha
rearrangements. We now investigate PJA-BP expression and its correlation
with TCR delta gene deletion in thymocytes. Our electrophoretic mobility
shift assay experiments showed that the PJA-BP is evolutionary conserved in
human, murine and simian thymocytes. Using a large series of human
hematopoietic malignancies (n = 30), we conclude that PJA-BP expression is
thymocyte specific and seems to be restricted to thymocytes committed to
the TCR alphabeta lineage. Analysis of seven well-defined human thymocyte
subpopulations showed that preferential deltaRec-psiJalpha rearrangements
as well as PJA-BP expression can be detected from the immature
CD34-/CD1+/CD3- /CD4+/CD8alpha+beta- thymocyte differentiation stage
onwards. These experiments indicate that expression of PJA-BP in human
thymocytes starts simultaneously with preferential deltaRec-psiJalpha
rearrangements, which supports our hypothesis that PJA-BP is one of the
factors involved in the preferential recombination of deltaRec to
psiJalpha.
相似文献
44.
M S Bartlett J A Fishman S F Queener M M Durkin M A Jay J W Smith 《Journal of clinical microbiology》1988,26(6):1100-1102
Rats free of latent Pneumocystis carinii organisms were immunosuppressed with adrenal corticosteroids and transtracheally injected with P. carinii. These animals subsequently developed P. carinii pneumonia. Infection was accomplished by using organisms from infected rat lung or from culture. Diffuse infection was produced with no significant differences in the numbers of organisms found in various lobes of the lungs. Infections progressed over time so that by 6 weeks postinoculation all animals were heavily infected. Infection by transtracheal injection has three advantages over current models. First, transtracheal injection provides a reliable model which is not dependent on naturally occurring latent Pneumocystis infection. Second, transtracheal injection allows the perpetuation of specific Pneumocystis strains. Third, transtracheal injection is a more rapid and economical means of producing severe Pneumocystis pneumonia. 相似文献
45.
Rottbauer W Just S Wessels G Trano N Most P Katus HA Fishman MC 《Genes & development》2005,19(13):1624-1634
The strength of the heart beat can accommodate in seconds to changes in blood pressure or flow. The mechanism for such homeostatic adaptation is unknown. We sought the cause of poor contractility in the heart of the embryonic zebrafish with the mutation dead beat. We find through cloning that this is due to a mutation in the phospholipase C gamma1 (plcgamma1) gene. In mutant embryos, contractile function can be restored by PLCgamma1 expression directed selectively to cardiac myocytes. In other situations, PLCgamma1 is known to transduce the signal from vascular endothelial growth factor (VEGF), and we show here that abrogation of VEGF also interferes with cardiac contractility. Somewhat unexpectedly, FLT-1 is the responsible VEGF receptor. We show that the same system functions in the rat. Blockage of VEGF-PLCgamma1 signaling decreases calcium transients in rat ventricular cardiomyocytes, whereas VEGF imposes a positive inotropic effect on cardiomyocytes by increasing calcium transients. Thus, the muscle of the heart uses the VEGF-PLCgamma1 cascade to control the strength of the heart beat. We speculate that this paracrine system may contribute to normal and pathological regulation of cardiac contractility. 相似文献
46.
47.
Effects of the aminonucleoside of puromycin on glomerular epithelial cells in vitro. 总被引:2,自引:7,他引:2
Glomerular epithelial cells (GECs) in vitro provide a useful model for the study of the mechanism(s) underlying the nephrotic syndrome of rats induced by the aminonucleoside of puromycin (PAN). Some of the toxicities of PAN are nonspecific, in that the constituent molecules of PAN (adenosine and puromycin) cause similar effects in vitro. These include GEC blebbing and rounding, reduced uptake of precursors of protein (leucine) and glycoprotein (glucosamine) synthesis, and increased permeability of the GEC membrane to adenosine. Some of the effects of PAN are not reproduced by adenosine or puromycin and are inhibited by the simultaneous presence of N6-monomethyl adenosine (MMA), a PAN analog and an in vivo blocker of nephrosis due to PAN. These processes may be related to the nephrotic syndrome and include the loss of adhesion to plastic; a reduction in the incorporation of 14C-glucosamine and 35S-sulfate both into molecules removable from the GEC surface by neuraminidase and into those moieties precipitated from the culture media by TCA; a marked reduction in the "ordering" of the lipids of the rigid GEC membrane, which is possibly dependent upon cell-surface proteins. These morphologic alterations in GECs and in the distribution of negatively charged molecules, which are either secreted or on the cell surface, correlate with observations made in PAN-induced nephrosis in rats in vivo. These include changes in the turnover and the array of sialic acid and heparan sulfate glycoprotein on the GECs and the glomerular basement membrane. The in vitro sensitivity of GECs to PAN and the effects of MMA suggest a role for these cells in in vivo aminonucleoside nephrotoxicity, where alterations in both the morphology and the anionic topology of GECs participate in the development of proteinuria. 相似文献
48.
Oral administration of muscle derived small molecules inhibits tumor spread while promoting normal cell growth in mice 总被引:5,自引:0,他引:5
Bar-Yehuda S Farbstein T Barer F Ohana G Fishman P 《Clinical & experimental metastasis》1999,17(6):531-535
Tumor metastases are extremely rare in striated muscles. This is surprising given the fact that this tissue constitutes 60%
of body weight. The present study focuses on small molecules produced and secreted by muscle cells which possess anti-cancer
activity in vivo. Recently we have shown that a low molecular weight fraction (<1000 Dalton) of skeletal muscle cell conditioned medium (muscle
factor-MF), markedly inhibits the proliferation of carcinoma, sarcoma or melanoma cell lines in vitro. The MF exerts a cytostatic effect on tumor cell growth and arrests the cells in the G0/G1 of the cell cycle. However, normal
cell proliferation, such as bone marrow and fibroblasts, was stimulated following incubation with MF. In this study, the effect
of orally administered MF on melanoma and sarcoma growth was examined in mice. The administration of MF to mice inoculated
intravenously with melanoma (B16–F10) or sarcoma (MCA-105) cells, resulted in a statistically significant inhibition of metastatic
lung foci. In a different model, melanoma was induced in the foot pad and after development of a local lesion, the leg was
amputated. A prolonged survival time was observed in the MF treated groups. Since the MF stimulated bone marrow cell proliferation
in vitro, we decided to test its efficacy as an inhibitor of the myelotoxic effect exerted by chemotherapy, in vivo. MF, administered after chemotherapy, restored the number of white blood cells and yielded an increased percentage of neutrophils
compared with the decline in these parameters after administration of chemotherapy alone. Thus, it is indicated that MF exerted
a systemic anti tumor and chemoprotective effect when given orally. It can be concluded that it is bioavailable and is not
biodegradable in the digestive system. MF may be considered as a potential therapy for the prevention of tumor spread.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
49.
Missense mutation in a von Willebrand factor type A domain of the alpha 3(VI) collagen gene (COL6A3) in a family with Bethlem myopathy 总被引:2,自引:0,他引:2
Pan TC; Zhang RZ; Pericak-Vance MA; Tandan R; Fries T; Stajich JM; Viles K; Vance JM; Chu ML; Speer MC 《Human molecular genetics》1998,7(5):807-812
The Bethlem myopathy is a rare autosomal dominant proximal myopathy
characterized by early childhood onset and joint contractures. Evidence for
linkage and genetic heterogeneity has been established, with the majority
of families linked to 21q22.3 and one large family linked to 2q37,
implicating the three type VI collagen subunit genes, COL6A1 (chromosome
21), COL6A2 (chromosome 21) and COL6A3 (chromosome 2) as candidate genes.
Mutations of the invariant glycine residues in the triple-helical
domain-coding region of COL6A1 and COL6A2 have been reported previously in
the chromosome 21-linked families. We report here the identification of a
G-->A mutation in the N-terminal globular domain-coding region of COL6A3
in a large American pedigree (19 affected, 12 unaffected), leading to the
substitution of glycine by glutamic acid in the N2 motif, which is
homologous to the type A domains of the von Willebrand factor. This
mutation segregated to all affected family members, to no unaffected family
members, and was not identified in 338 unrelated Caucasian control
chromosomes. Thus mutations in either the triple-helical domain or the
globular domain of type VI collagen appear to cause Bethlem myopathy.
相似文献
50.
An allergic reaction following intrauterine insemination 总被引:1,自引:0,他引:1
Intrauterine insemination is a common procedure used for the treatment of
different causes of infertility. Adverse reactions associated with this
procedure are very rare and usually the procedure is well tolerated by the
patient. We report a case of an allergic reaction after intrauterine
insemination. The patient developed fever, difficulty breathing and
wheezing in both lung fields. Although a low concentration of penicillin in
the medium was used, it caused a significant allergic reaction. When
intrauterine insemination was performed in subsequent cycles with an
antibiotic-free medium, no allergic reaction occurred, and the procedure
was well tolerated by the patient. A careful allergy history is essential
in patients pursuing infertility treatment where antibiotics are utilized.
Patients who are known to be allergic to penicillin should have semen
prepared by an antibiotic-free medium.
相似文献