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41.
O. Schatz Johannes R. Bogner F.-D. Goebel 《Journal of molecular medicine (Berlin, Germany)》1997,75(1):28-34
Patients suffering from the acquired immune deficiency syndrome (AIDS) have a 20000-fold increased risk of developing a severe
form of Kaposi’s sarcoma (KS), a previously rare malignancy involving sharply defined nodular lesions of the skin and/or oral
mucosa. Epidemiological evidence has long suggested that an infectious agent is the probable cause of KS. Recently sequences
from a putative new herpesvirus have been found to be associated with KS in virtually 100% of the cases analyzed. The suspected
etiological agent, a new human herpesvirus termed Kaposi’s sarcoma associated herpes virus (human herpes virus 8) has now
been propagated in cell culture. This significant advance should form the basis for a detailed analysis of the pathogenetic
mechanisms involved in the development of KS.
Received: 4 June 1996 / Accepted: 5 August 1996 相似文献
42.
Pore formation by the Escherichia coli hemolysin: evidence for an association-dissociation equilibrium of the pore-forming aggregates. 总被引:9,自引:16,他引:9 下载免费PDF全文
Lipid bilayer experiments were performed in the presence of hemolysin of Escherichia coli. The toxin had a rather low activity in membranes formed of pure lipids, such as phosphatidylcholine or phosphatidylserine. In membranes from asolectin, a crude lipid mixture from soybean, hemolysin was able to increase the conductance by many orders of magnitude in a steep concentration-dependent fashion, which suggested that several hemolysin molecules could be involved in the conductive unit. Furthermore, the much higher toxin activity in asolectin membranes would be consistent with the assumption that this lipid contains a receptor needed for membrane activity of the toxin. The results of single-channel records showed that the membrane activity of hemolysin is due to the formation of ion-permeable channels with a single-channel conductance of about 500 pS in 0.15 M KCl. The hemolysin channel seemed to be formed by a toxin oligomer which showed an association-dissociation reaction and had a mean lifetime of about 2 s at small transmembrane voltages. The conductance of the hemolysin channels was only moderately dependent on the salt concentration in the aqueous phase. Zero-current membrane potential experiments showed that the hemolysin channel is cation selective. The mobility sequence of the cations in the channel was similar to their mobility sequence in the aqueous phase, which was consistent with the assumption that the hemolysin channel is wide and that the interior field strength is not very high. From the single-channel conductance, a lower limit of about 1.0 nm for the effective channel diameter could be estimated. 相似文献
43.
44.
Hemolysin supports survival but not entry of the intracellular bacterium Listeria monocytogenes. 总被引:27,自引:24,他引:27 下载免费PDF全文
The gram-positive bacterium Listeria monocytogenes is a facultative intracellular pathogen. The only known property of L. monocytogenes which has been shown to be involved in virulence is a hemolysin, listeriolysin (J. L. Gaillard, P. Berche, and P. Sansonetti, Infect. Immun. 52:50-55, 1986; S. Kathariou, P. Metz, H. Hof, and W. Goebel, J. Bacteriol. 169:1291-1297, 1987). Using our previously obtained transposon Tn916-induced hemolysin-negative mutants of L. monocytogenes Sv1/2a (Mackaness strain), we demonstrated that the loss of hemolysin reduced significantly the rate of survival of the bacteria in mouse peritoneal macrophages but did not reduce their uptake. It was further shown that virulent L. monocytogenes strains could invade the mouse embryo fibroblast 3T6 cell line, i.e., mammalian cells which are nonprofessional phagocytes. This uptake was inhibited by cytochalasin B and hence seems to be accomplished by parasite-induced endocytosis. Hemolysin was not essential for this step. Strains of other Listeria species could not efficiently penetrate the 3T6 cells. 相似文献
45.
G. Hunsmann J. Schneider H. Bayer R. Kurth A. Werner H. D. Brede V. Erfle W. Mellert H. R. Brodt L. Bergmann I. Helm I. Scharrer W. Kreuz H. Berthold P. Wernet E. M. Schneider K. Schimpf U. Egli U. Bienzle H. Schmitz P. Kern G. Krüger H. Rasokat E. Lechler E. Seifried P. Hellstern W. Schneider E. Holzer F. -D. Goebel R. Hehlmann 《Journal of molecular medicine (Berlin, Germany)》1985,63(5):233-235
Summary In 1984 10,281 sera were collected in the FRG and examined for antibodies to HTLV-III (LAV) with an enzyme-linked immunosorbent assay and confirmative tests. Of the German AIDS patients 81% have antibodies. Individuals belonging to AIDS risk groups, homosexuals, haemophiliacs and i.v. drug abusers, have antibody frequencies between 25%–72%. The detection of HTLV-III antibodies in blood donours indicates that the virus is being transmitted by blood transfusions.Abbreviations AIDS
acquired immunodeficiency syndrome
- LAS
lymphadenopathy syndrome
- ARC
AIDS related complex
- LAV
lymphadenopathy associated virus
- HTLV-III
human T-lymphotropic virus type III
- HBV
hepatitis B virus 相似文献
46.
Identification of a new locus for autosomal dominant non-syndromic hearing impairment (DFNA7) in a large Norwegian family 总被引:3,自引:0,他引:3
Fagerheim T; Nilssen O; Raeymaekers P; Brox V; Moum T; Elverland HH; Teig E; Omland HH; Fostad GK; Tranebjaerg L 《Human molecular genetics》1996,5(8):1187-1191
Hereditary hearing impairment affects about 1 in 1000 newborns. In most
cases hearing loss is non-syndromic with no other clinical features, while
in other families deafness is associated with specific clinical
abnormalities. Analysis of large families with non-syndromic and syndromic
deafness have been used to identify genes or gene locations that cause
hearing impairment. The present report describes a large Norwegian family
with autosomal dominant non-syndromic, progressive high tone hearing loss
with linkage to 1q21-q23. A maximum LOD score of 7.65 (theta = 0.00) was
obtained with the microsatellite marker D1S196. Analysis of recombinant
individuals maps the deafness gene (DFNA7) to a 22 cM region between D1S104
and D1S466. The region contains several attractive candidate genes. This
report supports the idea of extensive genetic heterogeneity in hereditary
hearing impairment and represents the first localization of a deafness gene
in a Norwegian family.
相似文献
47.
Charles Varnell Jr Lyndsay A. Harshman Laurie Smith Chunyan Liu Shiran Chen Samhar Al-Akash Gina-Marie Barletta Craig Belsha Paul Brakeman Abanti Chaudhuri Paul Fadakar Rouba Garro Caroline Gluck Jens Goebel David Kershaw Debora Matossian Corina Nailescu Hiren P. Patel Cozumel Pruette Saritha Ranabothu Nancy Rodig Jodi Smith Judith Sebestyen VanSickle Patricia Weng Lara Danziger-Isakov David K. Hooper Michael Seifert 《American journal of transplantation》2021,21(8):2740-2748
There are limited data on the impact of COVID-19 in children with a kidney transplant (KT). We conducted a prospective cohort study through the Improving Renal Outcomes Collaborative (IROC) to collect clinical outcome data about COVID-19 in pediatric KT patients. Twenty-two IROC centers that care for 2732 patients submitted testing and outcomes data for 281 patients tested for SARS-CoV-2 by PCR. Testing indications included symptoms and/or potential exposures to COVID-19 (N = 134, 47.7%) and/or testing per hospital policy (N = 154, 54.8%). Overall, 24 (8.5%) patients tested positive, of which 15 (63%) were symptomatic. Of the COVID-19-positive patients, 16 were managed as outpatients, six received non-ICU inpatient care and two were admitted to the ICU. There were no episodes of respiratory failure, allograft loss, or death associated with COVID-19. To estimate incidence, subanalysis was performed for 13 centers that care for 1686 patients that submitted all negative and positive COVID-19 results. Of the 229 tested patients at these 13 centers, 10 (5 asymptomatic) patients tested positive, yielding an overall incidence of 0.6% and an incidence among tested patients of 4.4%. Pediatric KT patients in the United States had a low estimated incidence of COVID-19 disease and excellent short-term outcomes. 相似文献
48.
K. M. Goebel W. D. Gassel F. D. Goebel H. Kaffarnik 《Journal of molecular medicine (Berlin, Germany)》1972,50(17):849-851
Summary Hexokinase deficiency in the red cells caused a hemolytic anemia in a 28 y. old woman who revealed multiple malformations and a latent diabetes mellitus.Supported by Deutsche Forschungsgemeinschaft (Grant Go 236/2). 相似文献
49.
50.