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61.
Natural killer (NK) cells are large granular lymphocytes (LGLs) that contain distinct lysosomal granules. The present study was undertaken to determine if these lysosomes contain glycosaminoglycans (GAGs) similar to those previously described in myeloid cells. Mononuclear cells from human blood were stained with HNK-1 fluoresceinated monoclonal antibody, and the NK cell population reactive with this antibody were isolated with a fluorescence-activated cell sorter (FACS). Specific staining of sulfated macromolecules with the cationic reagent, high iron diamine, was observed in the lysosomal granules of 90% of the HNK-1 positive cells. Staining in the same location was also observed in the unsorted LGLs, presumed to be NK cells, and intense staining of the cell surface was also a prominent feature of these cells. Surface staining was not evident in the majority of the FACS- separated NK cells. Digestion with chondroitinase ABC or treatment with nitrous acid reduced the staining in both locations; after sequential treatment with both chondroitinase and nitrous acid, little or no staining was seen. The presence of chondroitin sulfate (and/or dermatan sulfate) and heparan sulfate was also shown by the finding that incubation of the isolated NK cells with 35S-sulfate yielded cell- associated radiolabeled macromolecules with the characteristics of these two groups of GAGs. Of the labeled GAG pool, 60% was degraded by chondroitinase and 40% was susceptible to nitrous acid treatment. LGLs of a patient with Chediak-Higashi syndrome was also stained, and intracellular sulfate staining was clearly localized to the enlarged granules, supporting the conclusion that the lysosomes are the major site of intracellular accumulation of GAGs in normal NK cells. 相似文献
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63.
Human marrow erythropoiesis in culture. I. Characterization of methylcellulose colony assay 总被引:11,自引:0,他引:11
We examined the morphological and functional characteristics of human marrow erythrocytes cultured with a recently developed methylcellulose colony assay technique. Erythrocytic cells in various stages of development were observed, and a significant degree of maturational synchrony within individual colonies was noted. By light microscopy, colonies consisting of late normoblasts appeared compact, had an orange hue attributable to their hemoglobin, and demonstrated pseudoperoxidase activity, whereas colonies composed of early erythroblasts grew less compact or in clusters of smaller cell aggregates and showed no reddish tinge. Colonies possessing intermediate features were also observed. Maturational synchrony of individual colonies was confirmed using ransmission and scanning electron microscopy. The ultrastructure and cytochemistry of most immature cells were normal. The mature erythrocytes, however, were severely microcytic and hypochromic and contained one to several Heinz bodies. These defects in the cytoplasmic maturation of erythrocytes corresponded with impaired granulocytic maturation in culture, which we observed previously, and suggest environmental or nutritional defects in culture. Linearity of the method was confirmed using five normal bone marrows. Erythropoietin dose-responses observed in ten normal marrows were comparable to the previously reported results and revealed significant variation in individual plating efficiencies. 相似文献
64.
The management of stage I--II Hodgkin's disease with irradiation alone or combined modality therapy: the Stanford experience 总被引:1,自引:0,他引:1
At Stanford University, between 1968 and 1978, 230 patients with pathologic stage I--II Hodgkin's disease were treated on prospective clinical trials with either irradiation alone or irradiation followed by 6 cycles of adjuvant combination chemotherapy. The actuarial survival at 10 yr was 84% for patients in either treatment group. Freedom from relapse at 10 yr was 77% among patients treated with irradiation alone and 84% after treatment with combined modality therapy [p(Gehan) = 0.09]. Freedom from second relapse at 10 yr was 89% and 94%, respectively [p(Gehan) = 0.56]. Several prognostic factors were evaluated in order to identify patients at high risk for relapse or with poor ultimate survival after initial treatment with irradiation alone. Systemic symptoms, histologic subtype, age, and limited extranodal involvement (E-lesions) did not affect the prognosis of patients and failed to identify patients whose survival could be improved by the routine use of combined modality therapy. Patients with large mediastinal masses (mediastinal mass ratio greater than or equal to 1/3) had a significantly poorer freedom from relapse when treated with irradiation alone than when treated initially with combined modality therapy [45% versus 81% at 10 yr, p(Gehan) = 0.03). The 10-yr survival of these patients, however, was not significantly different (84% versus 74%). The implications of these observations on the management of patient with early stage Hodgkin's disease are discussed. 相似文献
65.
Priya M Miranda Viswanathan Mohan Sekhar Ganthimathy Ranjit M Anjana S Gunasekaran Venkatachalam Thiagarajan Thomas A Churchill Tatsuya Kin AM James Shapiro Jonathan RT Lakey 《Islets》2013,5(5):188-195
The aim of this study was to assess recovery, cell death, and cell composition of post-thaw cultured human islets. Cryopreserved islets were provided by the Clinical Islet Transplant Program, Edmonton, Canada. Islets were processed using media prepared in accordance with Pre-Edmonton and Edmonton protocols. Cryopreserved islets were rapidly thawed and cultured for 24 h, 3 d, 5 d, and 7 d, following which they were processed for histology. Islet quantification, integrity, morphology and tissue turnover were studied via hematoxylin and eosin stained sections. Ultrastructure was studied by electron microscopy and endocrine cell composition by immunohistochemistry. Using the Pre-Edmonton protocol, islet recovery was 50.1% and islet survival was 50% at 24 h while for the Edmonton protocol, the islet recovery was 69.4% (p < 0.001) and islet survival, 50% at ≈2.5 d. With an increasing culture duration although the physical integrity was retained there was an increasing loss of cohesivity both at light microscopic and at ultrastructure level regardless of the protocols used. Percentage islet survival and tissue turnover correlated negatively with culture duration in both protocols. The Edmonton protocol appears to preserve the islets better. However, culture duration adversely affects islet survival and quality, indicating the need for more optimal cryopreservation and culture techniques. 相似文献
66.
Karina Reis Kappáz Cappati RT Rodrigo Marques Tonella Aline Santos DamascenaPedro Caruso MD 《Journal of critical care》2013
Purpose
During the mechanical ventilation weaning process, the spontaneous breathing trial (SBT) is the confirmatory test of patients' capability to breathe unassisted. However, the SBT interobserver agreement rate (its reliability) is unknown, and our objective was to evaluate it.Materials and Methods
This is a prospective, multicentric and observational study. Patients were included when the SBT criteria were fulfilled. Two physicians and 2 respiratory therapists (RTs) rated each SBT. The SBT interobserver agreement was measured using κ statistic and also the percentage of agreement with its 95% credible interval (CrI) calculated by a Bayesian inference.Results
Ninety-three distinct physicians and 91 distinct RTs rated 130 SBTs. The κ coefficient was 0.46 for physicians and 0.57 for RT, indicating a moderate interobserver agreement rate. The percentage of agreement was 87.7% between physicians (95% CrI, 81.0%-92.3%) and 86.2% between RT (95% CrI, 79.2%-91.1%). The physicians' and RT' percentage of agreement were not statistically different (P = .71).Conclusions
The SBT interobserver agreement rate is only moderate for physicians and RT. The percentage of agreement between 2 different SBT observers is 79.2% to 92.3%. Therefore, a relevant percentage of patients will have different extubation decisions depending on the SBT observer. 相似文献67.
68.
69.
Robertson RT; Gallardo KA; Claytor KJ; Ha DH; Ku KH; Yu BP; Lauterborn JC; Wiley RG; Yu J; Gall CM; Leslie FM 《Cerebral cortex (New York, N.Y. : 1991)》1998,8(2):142-155
The role of basal forebrain-derived cholinergic afferents in the
development of neocortex was studied in postnatal rats. Newborn rat pups
received intraventricular injections of 192 IgG-saporin. Following survival
periods ranging from 2 days to 6 months, the brains were processed to
document the cholinergic lesion and to examine morphological consequences.
Immunocytochemistry for choline acetyltransferase (ChAT) and in situ
hybridization for ChAT mRNA demonstrate a loss of approximately 75% of the
cholinergic neurons in the medial septum and nucleus of the diagonal band
of Broca in the basal forebrain. In situ hybridization for glutamic acid
decarboxylase mRNA reveals no loss of basal forebrain GABAergic neurons.
Acetylcholinesterase histochemistry demonstrates a marked reduction of the
cholinergic axons in neocortex. Cholinergic axons are reduced throughout
the cortical layers; this reduction is more marked in medial than in
lateral cortical areas. The thickness of neocortex is reduced by
approximately 10%. Retrograde labeling of layer V cortico-collicular
pyramidal cells reveals a reduction in cell body size and also a reduction
in numbers of branches of apical dendrites. Spine densities on apical
dendrites are reduced by approximately 20-25% in 192 IgG- saporin-treated
cases; no change was detected in number of spines on basal dendrites. These
results indicate a developmental or maintenance role for cholinergic
afferents to cerebral cortical neurons.
相似文献
70.