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11.
M F Reiser 《The American journal of psychiatry》1988,145(2):148-153
Psychiatry is part of medicine, and developing competence to deal with the mental life of patients is an essential part of general medical as well as psychiatric subspecialty education. As psychiatry's neurobiological data base, therapeutic armamentarium, scope of interest, and philosophical views expand and competitive pressures for time in residency training are intensified, teaching in the mental sciences and opportunities for residents to develop solid psychodynamic diagnostic and therapeutic skills are rapidly disappearing. However, brain science does not yet, and probably never will, fully explain the mind. The author urges psychiatric educators not to give up the mind or, worse yet, lose it by default. 相似文献
12.
Ontogeny of MAP2 and GFAP antigens in primary cultures of embryonic chick brain. Effect of substratum, oxygen tension, serum and Ara-C 总被引:1,自引:0,他引:1
Brain cells from embryonic chick (stage 28-29) were cultivated for 16 days under serum-free conditions. Nerve cells were found to mature during the first 7 days in culture, as indicated by the presence and developmental pattern of the relative amount of dendritic-specific microtubule-associated protein type 2 (MAP2). Maximal amounts of MAP2 antigen were found to be directly correlated with the number of cells plated out. Astroglia cell proliferation and differentiation, as measured by the amounts of glial fibrillary acidic protein (GFAP), were found to stabilize after a certain astrocyte cell density was reached. Variation in culture plate coating procedure, oxygen tension and addition of serum or of the cytostatic drug Ara-C were found to differently affect viability and maturation processes of astroglia and of nerve cells. Moreover, optimal culture conditions for long-term brain cell cultures are described. 相似文献
13.
G Reiser 《European journal of pharmacology》1992,227(1):89-93
The influence of an elevated level of cyclic AMP on the formation of nitric oxide was investigated in a neuronal cell line (108CC15; NG108-15), in which we had previously shown that nitric oxide mediates the activation of soluble guanylyl cyclase upon stimulation with the hormones bradykinin, endothelin, and serotonin. Maximal amplitude and duration of cyclic GMP response to bradykinin were about 2-fold greater in cells with cyclic AMP levels increased by forskolin pretreatment than in control cells with basal levels of cyclic AMP. Phosphodiesterase inhibitors (isobutylmethylxanthine or M&B 22,948 (zaprinast)) similarly increased the maximal amplitude of the cyclic GMP response to bradykinin, but, in contrast, slowed down the decay phase of the cyclic GMP response to a much greater extent. The cyclic GMP responses to bradykinin were suppressed with the same potency by L-arginine analogues in control and in forskolin-treated cells (IC50 of NG-monomethyl-L-arginine 2 microM, of nitro-L-arginine 0.7 microM). The transient rises of cyclic GMP levels induced by bradykinin and endothelin, which both cause release of Ca2+ from internal stores, were similarly enhanced by forskolin pretreatment. However, the transient cyclic GMP response to serotonin which is due to Ca2+ influx into the neuronal cell line via 5-hydroxytryptamine3 (5-HT3) receptors was not affected by raising the cyclic AMP levels by forskolin pretreatment. Thus, cyclic AMP seems to enhance nitric oxide formation which depends on Ca2+ release from internal stores. 相似文献
14.
15.
Sacral insufficiency fractures develop over a period of time and show time-dependent changes. We report on 15 CT examinations of 5 patients with early-stage insufficiency fractures of the sacrum. In 4 patients only irregular sclerosis without distinct fracture lines was present in 7 of 8 fractures. Of these 4 patients; 3 exhibited intraosseous gas inclusions in a ventral part of a lateral mass; 5 of 8 fractures disclosed a ventral cortical break. When distinct fracture lines had developed in 1 patient, intraosseous vacuum phenomenon had disappeared. Fracture lines evolve over weeks to months and show central bone absorption. The fractures can heal as demonstrated in 4 of 6 fractures in 3 patients, can persist over 1 year without significant changes or can progress to pseudoarthrosis with bone destruction similar to neuropathic joint disease. Intraosseous vacuum phenomena can persist to this stage. Intraosseous vacuum phenomenon is recognized as a potential finding in the early stage of sacral insufficiency fracture, which also is true for irregular sclerosis and ventral cortical disruption.
Correspondence to: A. Stäbler 相似文献
16.
Staphylococcal toxic shock toxin specifically binds to cultured human epithelial cells and is rapidly internalized. 总被引:2,自引:3,他引:2 下载免费PDF全文
Staphylococcal toxic shock syndrome toxin (TST) was labeled with 125I under mild conditions without apparent destruction of the molecule. [125I]TST bound specifically to human epithelial (Chang) cells in culture; the binding was inhibited by a 100-fold excess of unlabeled toxin. Scatchard analysis of the binding data indicated about 10(4) receptor sites per cell and a dissociation constant (Kd) of 4 X 10(-9) M. When cells pretreated with TST at 4 degrees C were swiftly transferred to 37 degrees C, the amount of surface-bound toxin rapidly declined, as determined by release of noninternalized label from the cell surface. Half-time (t1/2) of internalization was about 1.5 min. Ultrastructural studies showed that toxin labeled with ferritin-conjugated antibodies entered the cytoplasm via coated pits forming coated vesicles in the first 2 min of incubation at 37 degrees C. The coated vesicles coalesced with transport vesicles that are ultrastructurally unlike receptosomes. Thus, the unusual ultrastructural pattern of this internalization suggests that TST is initially internalized by receptor-mediated endocytosis and then enters an alternate pathway involving translocation in special transport vesicles, perhaps to other cells. 相似文献
17.
18.
Predominance of null mutations in ataxia-telangiectasia 总被引:15,自引:4,他引:15
Gilad S; Khosravi R; Shkedy D; Uziel T; Ziv Y; Savitsky K; Rotman G; Smith S; Chessa L; Jorgensen TJ; Harnik R; Frydman M; Sanal O; Portnoi S; Goldwicz Z; Jaspers NG; Gatti RA; Lenoir G; Lavin MF; Tatsumi K; Wegner RD; Shiloh Y; Bar-Shira A 《Human molecular genetics》1996,5(4):433-439
Ataxia-telangiectasia (A-T) is an autosomal recessive disorder involving
cerebellar degeneration, immunodeficiency, chromosomal instability,
radiosensitivity and cancer predisposition. The responsible gene, ATM, was
recently identified by positional cloning and found to encode a putative
350 kDa protein with a Pl 3-kinase-like domain, presumably involved in
mediating cell cycle arrest in response to radiation-induced DNA damage.
The nature and location of A-T mutations should provide insight into the
function of the ATM protein and the molecular basis of this pleiotropic
disease. Of 44 A-T mutations identified by us to date, 39 (89%) are
expected to inactivate the ATM protein by truncating it, by abolishing
correct initiation or termination of translation, or by deleting large
segments. Additional mutations are four smaller in-frame deletions and
insertions, and one substitution of a highly conserved amino acid at the Pl
3-kinase domain. The emerging profile of mutations causing A-T is thus
dominated by those expected to completely inactivate the ATM protein. ATM
mutations with milder effects may result in phenotypes related, but not
identical, to A-T.
相似文献
19.
High throughput parallel analysis of hundreds of patient samples for more than 100 mutations in multiple disease genes 总被引:5,自引:0,他引:5
Shuber AP; Michalowsky LA; Nass GS; Skoletsky J; Hire LM; Kotsopoulos SK; Phipps MF; Barberio DM; Klinger KW 《Human molecular genetics》1997,6(3):337-347
As more mutations are identified in genes of known sequence, there is a
crucial need in the areas of medical genetics and genome analysis for
rapid, accurate and cost-effective methods of mutation detection. We have
developed a multiplex allele-specific diagnostic assay (MASDA) for analysis
of large numbers of samples (> 500) simultaneously for a large number of
known mutations (> 100) in a single assay. MASDA utilizes
oligonucleotide hybridization to interrogate DNA sequences. Multiplex DNA
samples are immobilized on a solid support and a single hybridization is
performed with a pool of allele-specific oligonucleotide (ASO) probes. Any
probes complementary to specific mutations present in a given sample are in
effect affinity purified from the pool by the target DNA. Sequence-specific
band patterns (fingerprints), generated by chemical or enzymatic sequencing
of the bound ASO(s), easily identify the specific mutation(s). Using this
design, in a single diagnostic assay, we tested samples for 66 cystic
fibrosis (CF) mutations, 14 beta-thalassemia mutations, two sickle cell
anemia (SCA) mutations, three Tay-Sachs mutations, eight Gaucher mutations,
four mutations in Canavan disease, four mutations in Fanconi anemia, and
five mutations in BRCA1. Each mutation was correctly identified. Finally,
in a blinded study of 106 of these mutations in > 500 patients, all
mutations were properly identified. There were no false positives or false
negatives. The MASDA assay is capable of detecting point mutations as well
as small insertion or deletion mutations. This technology is amenable to
automation and is suitable for immediate utilization for high-throughput
genetic diagnostics in clinical and research laboratories.
相似文献
20.
Preliminary observations on polar body extrusion and pronuclear formation in human oocytes using time-lapse video cinematography 总被引:10,自引:17,他引:10
Payne D; Flaherty SP; Barry MF; Matthews CD 《Human reproduction (Oxford, England)》1997,12(3):532-541
In this study, we have used time-lapse video cinematography to study
fertilization in 50 human oocytes that had undergone intracytoplasmic sperm
injection (ICSI). Time-lapse recording commenced shortly after ICSI and
proceeded for 17-20 h. Oocytes were cultured in an environmental chamber
which was maintained under standard culture conditions. Overall, 38 oocytes
(76%) were fertilized normally, and the fertilization rate and embryo
quality were not significantly different from 487 sibling oocytes cultured
in a conventional incubator. Normal fertilization followed a defined course
of events, although the timing of these events varied markedly between
oocytes. In 35 of the 38 fertilized oocytes (92%), there were circular
waves of granulation within the ooplasm which had a periodicity of 20-53
min. The sperm head decondensed during this granulation phase. The second
polar body was then extruded, and this was followed by the central
formation of the male pronucleus. The female pronucleus formed in the
cytoplasm adjacent to the second polar body at the same time as, or
slightly after, the male pronucleus, and was subsequently drawn towards the
male pronucleus until the two abutted. Both pronuclei then increased in
size, the nucleoli moved around within the pronuclei and some nucleoli
coalesced. During pronuclear growth, the organelles contracted from the
cortex towards the centre of the oocyte, leaving a clear cortical zone. The
oocyte decreased in diameter from 112 to 106 microm (P < 0.0001) during
the course of the observation period. The female pronucleus was
significantly smaller in diameter than the male pronucleus (24.1 and 22.4
microm respectively, P = 0.008) and contained fewer nucleoli (4.2 and 7.0
respectively, P < 0.0001). After time-lapse recording, oocytes were
cultured for 48 h prior to embryo transfer or cryopreservation. Embryo
quality was related to fertilization events and periodicity of the
cytoplasmic wave, and it was found that good quality embryos arose from
oocytes that had more uniform timing from injection to pronuclear abuttal
and tended to have a longer cytoplasmic wave. In conclusion, we have shown
that time-lapse video cinematography is an excellent tool for studying
fertilization and early embryo development, and have demonstrated that
human fertilization comprises numerous complex dynamic events.
相似文献