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81.
Ability of bacteria associated with chronic inflammatory disease to stimulate E-selectin expression and promote neutrophil adhesion. 总被引:7,自引:13,他引:7 下载免费PDF全文
R P Darveau M D Cunningham T Bailey C Seachord K Ratcliffe B Bainbridge M Dietsch R C Page A Aruffo 《Infection and immunity》1995,63(4):1311-1317
Porphyromonas gingivalis, Pseudomonas aeruginosa, and Helicobacter pylori have been shown to be associated with adult periodontal disease, chronic lung infections, and peptic ulcers, respectively. The ability of these bacteria to stimulate E-selectin expression and promote neutrophil adhesion, two components necessary for the recruitment of leukocytes in response to infection, was investigated. Little or no stimulation of E-selectin expression was observed with either P. gingivalis or H. pylori when whole cells, lipopolysaccharide (LPS), or cell wall preparations added to human umbilical cord vein endothelial cells were examined. P. aeruginosa was able to induce E-selectin to near-maximal levels; however, it required approximately 100 to 1,000 times more whole cells or LPS than that required by E. coli. Neutrophil-binding assays revealed that LPS and cell wall preparations obtained from these bacteria did not promote endothelial cell adhesiveness by E-selectin-independent mechanisms. In addition, P. gingivalis LPS blocked E-selectin expression by LPS obtained from other bacteria. We propose that lack of E-selectin stimulation and the inability to promote endothelial cell adhesiveness are two additional indications of low biologically reactive LPS. We suggest that this property of LPS may contribute to host tissue colonization. In addition, the ability of P. gingivalis to inhibit E-selectin expression may represent a new virulence factor for this organism. 相似文献
82.
In this study, the relationship between physiological arousal, as indexed by heart rate variability, was examined in boys with fragile X syndrome (FXS) and typically developing boys matched on chronological age. In addition, the relationship of heart activity to clinical and molecular factors in the group of boys with FXS was examined. Results suggest that boys with FXS have higher levels of heart activity during the passive phases, as reflected in shorter heart periods. This high level of heart activity appears to be due to increased sympathetic activity and reduced parasympathetic activity. Boys with FXS did not display the expected patterns of heart activity in response to phases of increasing challenge, and sympathetic and parasympathetic systems did not appear coordinated in these boys with FXS. Clinical factors may be related to neural regulation of heart activity while molecular factors do not appear to be. 相似文献
83.
Schover LR; Thomas AJ; Falcone T; Attaran M; Goldberg J 《Human reproduction (Oxford, England)》1998,13(4):862-866
Many couples undergoing in-vitro fertilization (IVF) are at a higher risk
of having a child with a genetic abnormality. In a sample of 55 consecutive
couples starting IVF, only 33% had no genetic risk factor. The most common
genetic risks were advanced maternal age and possible abnormalities
associated with severe male infertility. Despite education on these risks,
71% of couples had no interest in receiving formal genetic counselling.
Only 14% of couples at risk would consider using a gamete donor to avoid
transmitting a genetic disorder to a child. The triple test to screen for
fetal abnormalities was acceptable to 82% of couples, but only 47% planned
to have amniocentesis or chorionic villi sampling. Couples were
significantly more likely to opt for prenatal testing if they would
consider terminating a pregnancy should the fetus have a severe genetic
abnormality (P < 0.01). Roman Catholic couples tended to have more
conservative attitudes about pregnancy termination. Socio-economic status
and whether the infertility factor was male or female were not predictors
of a couple's attitudes.
相似文献
84.
Optimization of a method for deactivation of platelet-activating factor:acetylhydrolase in serum for use in in-vitro fertilization culture media 总被引:1,自引:0,他引:1
Embryos produced by in-vitro fertilization (IVF) may produce less
platelet-activating factor (PAF) than is optimal for development. It was
previously shown that supplementation of culture media with PAF results in
a significant increase in pregnancy rate. Human embryos are often cultured
in media supplemented with serum containing the enzyme PAF:acetylhydrolase
(PAF:AH; EC 3.1.1.47), which hydrolyses PAF to its inactive form, lyso-PAF.
Thus, effective supplementation of media with PAF requires inactivation of
this enzyme. In this study we examine the efficacy of the methods of PAF:AH
deactivation used for PAF supplementation of IVF culture medium. When the
effectiveness of a commonly used acid treatment protocol (pH 3.0 at room
temperature for 5 min) was examined, it was found that it was not
completely effective for the majority of sera. When synthetic PAF was added
to 18 serum samples which had been acid treated, five had 90-100% of the
original PAF remaining after 24 h (showing that the acid treatment was
effective), eight had from 10-90% of the original PAF remaining after 24 h,
and five samples had 0-10%. The extent to which PAF:AH was susceptible to
deactivation was not associated with the activity in the serum prior to
treatment, the serum oestradiol concentration, or the cause of infertility.
The period of acidification and the incubation temperature were assessed to
develop a new acid-treatment protocol (20 min acid treatment at 37 degrees
C) which was able to deactivate PAF:AH effectively in all sera (53/53)
examined. A trial was performed to assess the effect of acid treatment of
serum for 5 min at room temperature compared with the new protocol (20 min
at 37 degrees C) on IVF outcome, following PAF supplementation of IVF
culture medium. Oocyte recovery, fertilization and embryo development rates
were equivalent for both groups and approximately equal numbers of embryos
were transferred or cryopreserved. Pregnancy rates were not significantly
different (14.6 versus 20.0%) for the two treatments, with a trend towards
a higher pregnancy rate with the new acid- treatment protocol. The results
show that this new procedure for acid treatment of serum in combination
with PAF supplementation does not have detrimental effects on embryos and
their pregnancy outcome and is therefore suitable for use in IVF.
相似文献
85.
86.
Positional cloning of the gene for X-linked retinitis pigmentosa 3: homology with the guanine-nucleotide-exchange factor RCC1 总被引:6,自引:7,他引:6
Roepman R; van Duijnhoven G; Rosenberg T; Pinckers AJ; Bleeker-Wagemakers LM; Bergen AA; Post J; Beck A; Reinhardt R; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(7):1035-1041
The gene for retinitis pigmentosa 3 (RP3), the most frequent form of X-
linked RP (XLRP), has been mapped previously to a chromosome interval of
less than 1000 kbp between the DXS1110 marker and the OTC locus at
Xp21.1-p11.4. Employing a novel technique, YAC Representation Hybridization
(YRH)', we have recently identified a small XLRP associated microdeletion
in this interval, as well as several putative exons including the 3' end of
a gene that was truncated by the deletion. cDNA library screening and
sequencing of a cosmid centromeric to the deletion has now enabled us to
identify numerous additional exons and to detect several point mutations in
patients with XLRP. The predicted gene product shows homology to RCC1, the
guanine-nucleotide- exchange factor (GEF) of the Ras-like GTPase Ran. Our
findings suggest that we have cloned the long-sought RP3 gene, and that it
may encode the GEF of a retina-specific GTP-binding protein.
相似文献
87.
The t(X;1)(p11.2;q21.2) translocation in papillary renal cell carcinoma fuses a novel gene PRCC to the TFE3 transcription factor gene 总被引:4,自引:2,他引:4
88.
Hao Wang Ingeborg Barisic Maria Loane Marie‐Claude Addor Linda M. Bailey Miriam Gatt Kari Klungsoyr Olatz Mokoroa Vera Nelen Amanda J. Neville Mary O'Mahony Anna Pierini Anke Rissmann Christine Verellen‐Dumoulin Hermien E.K. de Walle Awi Wiesel Katarzyna Wisniewska Lolkje T.W. de Jong‐van den Berg Helen Dolk Babak Khoshnood Ester Garne 《American journal of medical genetics. Part A》2019,179(4):595-601
We aimed to assess prevalence, birth outcome, associated anomalies and prenatal diagnosis of congenital clubfoot in Europe using data from the EUROCAT network, and to validate the recording of congenital clubfoot as a major congenital anomaly by EUROCAT registries. Cases of congenital clubfoot were included from 18 EUROCAT registries covering more than 4.8 million births in 1995–2011. Cases without chromosomal anomalies born during 2005–2009, were randomly selected for validation using a questionnaire on diagnostic details and treatment. There was 5,458 congenital clubfoot cases of which 5,056 (93%) were liveborn infants. Total prevalence of congenital clubfoot was 1.13 per 1,000 births (95% CI 1.10–1.16). Prevalence of congenital clubfoot without chromosomal anomaly was 1.08 per 1,000 births (95% CI 1.05–1.11) and prevalence of isolated congenital clubfoot was 0.92 per 1,000 births (95% CI 0.90–0.95), both with decreasing trends over time and large variations in prevalence by registry. The majority of cases were isolated congenital clubfoot (82%) and 11% had associated major congenital anomalies. Prenatal detection rate of isolated congenital clubfoot was 22% and increased over time. Among 301 validated congenital clubfoot cases, diagnosis was confirmed for 286 (95%). In conclusion, this large population‐based study found a decreasing trend of congenital clubfoot in Europe after 1999–2002, an increasing prenatal detection rate, and a high standard of coding of congenital clubfoot in EUROCAT. 相似文献
89.
Characterization of the Mycobacterium bovis restriction fragment length polymorphism DNA probe pUCD and performance comparison with standard methods 下载免费PDF全文
O'Brien R Danilowicz BS Bailey L Flynn O Costello E O'Grady D Rogers M 《Journal of clinical microbiology》2000,38(9):3362-3369
In this study, the newly described Mycobacterium bovis restriction fragment length polymorphism (RFLP) typing probe pUCD was characterized by sequence analysis and the previously observed polymorphic banding pattern was reproduced with a combination of three oligonucleotide probes in a single, mixed hybridization. In addition, the ability of pUCD to distinguish between 299 M. bovis isolates from the Republic of Ireland was assessed in relation to established methods and a statistical function for objective comparison of RFLP probes was derived. It was found that typing with pUCD alone produced greater discrimination between M. bovis isolates than typing with the commonly used mycobacterial DNA probes IS6110, PGRS, and DR and also by the spoligotyping technique. pUCD and DR in combination produced the highest level of discrimination while maintaining a high level of concordance with known epidemiological data relating to the samples. The reduction of pUCD to the level of oligonucleotides should in future allow pUCD and DR to be included together in a mixed hybridization, thus producing a high level of M. bovis strain type discrimination from a single round of RFLP analysis. 相似文献
90.
Somatic mutation processes at a human minisatellite 总被引:6,自引:3,他引:6
Germline instability at human minisatellites frequently involves complex
inter-allelic transfers of repeat units usually restricted to one end of
the repeat array and apparently regulated by flanking DNA. In contrast,
nothing is known about the structural basis of somatic instability at
minisatellites. An electrophoretic size-enrichment strategy was therefore
developed at minisatellite MS32 (D1S8) to enable rare abnormal-length
mutants to be detected, validated and quantitated in blood DNA by single
molecule PCR. Structural analysis of rare mutant alleles in blood revealed
simple deletions/duplications of repeat unit blocks located at random along
the tandem repeat array, a mode of mutation completely different from that
seen in sperm. Furthermore, allele-specific suppression of sperm
instability at MS32 did not affect somatic instability. These data suggest
that conversion-based minisatellite mutation in sperm is completely
germline-specific and most likely meiotic in origin. Somatic instability
appears to occur by a separate pathway involving replication slippage or,
more likely, intra-allelic unequal crossing over.
相似文献