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61.
Takenoshita S; Hagiwara K; Gemma A; Nagashima M; Ryberg D; Lindstedt BA; Bennett WP; Haugen A; Harris CC 《Carcinogenesis》1997,18(7):1427-1429
The transforming growth factor-beta type II receptor (RII) is commonly
mutated in colon and gastric cancers with microsatellite instability (MI).
We utilized our series of lung cancers with MI and rare alleles of the
H-ras1 gene to determine the association between MI and RII mutations and
searched the entire RII coding region in 33 lung cancers with MI by
polymerase chain reaction-single-strand conformation polymorphism analysis.
We found no mutations, and these data support other recent evidence that
RII mutations rarely occur except in colon and gastric tumors with MI.
相似文献
62.
To investigate the population genetic structure of Trypanosoma evansi from domesticated animals, we have analysed 112 stocks from camels, buffaloes, cattle and horses using the tandemly repeated
coding sequence (MORF2) and minisatellite markers 292 and cysteine-rich acidic integral membrane protein (CRAM). We recorded
a total of six alleles at the MORF2 locus, seven at 292 and 12 at the CRAM loci. Nei’s genetic distance showed reduced allelic
diversity between buffaloes and cattle stocks (1.2) as compared to the diversity between camels and buffaloes (3.75) and camels
and cattle stock (1.69). The mean index of association (I
A
= 0.92) significantly deviated from zero, and the average number of multilocus genotypes (G/N ratio) was 0.21. Twenty-four
multilocus genotypes were defined from the combination of alleles at the three loci. The Kenyan sub-populations showed F
st
= 0.28 and analysis of molecular variance showed significant divergence (22.7%) between the Laikipia, Kulal and Galana regions.
The regional and host distribution of multi-locus genotypes significant population differentiation and high Nei’s genetic
distances suggest existence of genetic sub-structuring within T. evansi stocks while the few multi-locus genotypes and deviation of association index from zero indicate the lack of recombination.
In conclusion, this study reveals that some genetic sub-structuring does occur within T. evansi, which has a clonal population structure. 相似文献
63.
Christabel Enweronu-Laryea Kim E Dickson Sarah G Moxon Aline Simen-Kapeu Christabel Nyange Susan Niermeyer France Bégin Howard L Sobel Anne CC Lee Severin Ritter von Xylander Joy E Lawn 《BMC pregnancy and childbirth》2015,15(Z2):S4
Background
An estimated two-thirds of the world's 2.7 million newborn deaths could be prevented with quality care at birth and during the postnatal period. Basic Newborn Care (BNC) is part of the solution and includes hygienic birth and newborn care practices including cord care, thermal care, and early and exclusive breastfeeding. Timely provision of resuscitation if needed is also critical to newborn survival. This paper describes health system barriers to BNC and neonatal resuscitation and proposes solutions to scale up evidence-based strategies.Methods
The maternal and newborn bottleneck analysis tool was applied by 12 countries in Africa and Asia as part of the Every Newborn Action Plan process. Country workshops engaged technical experts to complete the survey tool, which is designed to synthesise and grade health system "bottlenecks" that hinder the scale up of maternal-newborn intervention packages. We used quantitative and qualitative methods to analyse the bottleneck data, combined with literature review, to present priority bottlenecks and actions relevant to different health system building blocks for BNC and neonatal resuscitation.Results
Eleven of the 12 countries provided grading data. Overall, bottlenecks were graded more severely for resuscitation. The most severely graded bottlenecks for BNC were health workforce (8 of 11 countries), health financing (9 out of 11) and service delivery (7 out of 9); and for neonatal resuscitation, workforce (9 out of 10), essential commodities (9 out of 10) and service delivery (8 out of 10). Country teams from Africa graded bottlenecks overall more severely. Improving workforce performance, availability of essential commodities, and well-integrated health service delivery were the key solutions proposed.Conclusions
BNC was perceived to have the least health system challenges among the seven maternal and newborn intervention packages assessed. Although neonatal resuscitation bottlenecks were graded more severe than for BNC, similarities particularly in the workforce and service delivery building blocks highlight the inextricable link between the two interventions and the need to equip birth attendants with requisite skills and commodities to assess and care for every newborn. Solutions highlighted by country teams include ensuring more investment to improve workforce performance and distribution, especially numbers of skilled birth attendants, incentives for placement in challenging settings, and skills-based training particularly for neonatal resuscitation.64.
65.
Background
Pneumocystis jiroveci pneumonia (PCP) is an important opportunistic infection among immunosuppressed patients, especially in those infected with human immunodeficiency virus (HIV). The clinical presentation of PCP in immunosuppressed patients have been well-reported in the literature. However, the clinical importance of PCP manifesting in the setting of an immunorestitution disease (IRD), defined as an acute symptomatic or paradoxical deterioration of a (presumably) preexisting infection, which is temporally related to the recovery of the immune system and is due to immunopathological damage associated with the reversal of immunosuppressive processes, has received relatively little attention until recently. 相似文献66.
The effect of fibrin polymers on thrombin-catalyzed factor XIIIa formation was studied in afibrinogenemic plasma. Fibrin polymers derived from des A fibrinogen and des A,B fibrinogen increased sixfold the rate of thrombin-catalyzed factor XIIIa formation in the presence of EDTA. Calcium chloride accelerated factor XIIIa formation 14-fold in the presence of des A,B fibrinogen without increasing the rate of thrombin formation. Fibrinopeptides A and B had no effect on factor XIIIa formation in afibrinogenemic plasma. Des A,B fibrinogen reduced by 20- to 40-fold the thrombin concentration required to activate factor XIII. Glycyl-L-prolyl-L-arginyl-L-proline (gly-pro-arg-pro), a fibrin polymerization inhibitor, inhibited des A and des A,B fibrinogen from enhancing thrombin-catalyzed factor XIIIa formation. Gly-pro-arg- pro did not modify factor XIIIa formation in afibrinogenemic plasma and did not inhibit thrombin cleavage of the chromogenic substrate S-2238. These results demonstrate that fibrin polymers accelerate thrombin- catalyzed plasma factor XIIIa formation. 相似文献
67.
AP-1和肿瘤的关系研究进展 总被引:4,自引:0,他引:4
转录因子AP-1(activatorprotein1),主要由Jun、Fos、ATF及JDP亚家族组成,亚家族单体以同源或异源二聚体的形式结合DNA靶序列,参与靶基因调节.对基因修饰小鼠和细胞的研究表明,AP-1参与细胞的正常生长和癌性转化过程,其在细胞中的作用取决于细胞类型、AP-1的组成和各组分的相对比例,也与刺激的种类密切相关.AP-1的活性受多种核因子调节,同时单体间也存在相互促进或拮抗作用.AP-1对各种刺激如应激、辐射或生长信号等作出生理或病理应答,参与细胞的增殖、分化和转化等过程,在肿瘤的形成、转移和侵袭中发挥重要作用,已经有学者研究通过抑制AP-1活性来发展抗肿瘤药物. 相似文献
68.
Comparison of clinical and self-reported diagnoses for participants on a community-based arthritis self-management programme 总被引:2,自引:0,他引:2
OBJECTIVE: With the advent of community-based arthritis education
programmes, it is important to determine the accuracy of participants'
self-reported diagnoses. The purpose of this study was to determine the
level of agreement between general practitioner (GP)-recorded and self-
reported diagnoses of participants attending an Arthritis Self- Management
Programme (ASMP). METHODS: Participants enrolling on the ASMP were asked to
(a) identify their type of arthritis via a self- administered postal
questionnaire and (b) obtain a written confirmation of their diagnosis from
their GP. The sample (n = 613) comprised mainly women (83%) with a mean age
of 58.8 yr (S.D. 12.6) and a mean disease duration of 15.4 yr (S.D. 12.5).
RESULTS: Participants' self-reported diagnoses were confirmed by GPs in 534
cases [87.1%, 95% confidence interval (CI): 84.4 89.8%]. Confirmed
diagnoses were reported by 86.9% (95% CI: 83.1-90.7%) of those with
osteoarthritis (OA) and 96.1% (95% CI: 93.6 98.6%) of those with rheumatoid
arthritis (RA). The concordance rate for all other types of arthritis
combined was lower at 60.5% (95% CI: 49.5-71.5%). There were no significant
differences with respect to age, gender, education, physical functioning,
duration of disease and number of GP visits between those who correctly
identified their type of arthritis and those who did not. CONCLUSIONS: This
study suggests that the majority of RA and OA participants attending an
arthritis education programme can correctly identify their specific type of
arthritis.
相似文献
69.
70.
The CTLA-4 gene region of chromosome 2q33 is linked to, and associated with, type 1 diabetes. Belgian Diabetes Registry 总被引:8,自引:1,他引:8
Nistico L; Buzzetti R; Pritchard LE; Van der Auwera B; Giovannini C; Bosi E; Larrad MT; Rios MS; Chow CC; Cockram CS; Jacobs K; Mijovic C; Bain SC; Barnett AH; Vandewalle CL; Schuit F; Gorus FK; Tosi R; Pozzilli P; Todd JA 《Human molecular genetics》1996,5(7):1075-1080
Susceptibility to autoimmune insulin-dependent (type 1) diabetes mellitus
is determined by a combination of environmental and genetic factors, which
include variation in MHC genes on chromosome 6p21 (IDDM1) and the insulin
gene on chromosome 11p15 (IDDM2). However, linkage to IDDM1 and IDDM2
cannot explain the clustering of type 1 diabetes in families, and a role
for other genes is inferred. In the present report we describe linkage and
association of type 1 diabetes to the CTLA-4 gene (cytotoxic T lymphocyte
associated-4) on chromosome 2q33 (designated IDDM12). CTLA-4 is a strong
candidate gene for T cell- mediated autoimmune disease because it encodes a
T cell receptor that mediates T cell apoptosis and is a vital negative
regulator of T cell activation. In addition, we provide supporting evidence
that CTLA-4 is associated with susceptibility to Graves' disease, another
organ- specific autoimmune disease.
相似文献