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991.
992.
Maartje H de Groot Hanna C van der Jagt‐Willems Jos PCM van Campen Willem F Lems Claudine JC Lamoth 《Geriatrics & Gerontology International》2012,12(4):573-585
Aim: Osteoporosis can cause vertebral fractures, which might lead to a flexed posture, impaired postural control and consequently increased fall risk. Therefore, the aim of the present review was to examine whether postural control of patients with osteoporosis, vertebral fractures, thoracic kyphosis and flexed posture is affected. Furthermore, instruments measuring postural control were evaluated and examined for sensitivity and easy clinical use. Methods: Until February 2011, electronic databases were systematically searched for cross‐sectional studies. Methodological quality was assessed with a modified Downs & Black scale. Results: Of the 518 found studies, 18 studies were included. Postural control was generally affected for patients with vertebral fractures, thoracic kyphosis and flexed posture. Patients with osteoporosis had impaired postural control when assessed with computerized instruments. Easy performance‐based tests did not show any impairments. Conclusions: There is evidence for an impaired postural control in all patient groups included. Impaired postural control is an important risk factor for falls. Functional performance tests are not sensitive and specific enough to detect affected postural control in patients with osteoporosis. To detect impaired postural control among osteoporotic patients and to obtain more insight into the underlying mechanisms of postural control, computerized instruments are recommended, such as easy‐to‐use ambulant motion‐sensing (accelerometry) technology. Geriatr Gerontol Int 2012; ??: ??–??. 相似文献
993.
ObjectiveTo investigate the anticonvulsant activity of the bulbs of Crinum jagus in experimental animals.MethodsThe uprooted bulbs were air dried for a week and ground into creamy-paste. 200g of paste was macerated each in 2 litres of water, ethanol and petroleum ether and filtered after 48 h. The obtained filtrates were each evaporated at the appropriate temperature to solid residue. The residues were further fractionated with successive changes of petroleum ether, ethyl acetate and n-butanol into a pooled filtrate which was further evaporated to dry solid brown-paste. Phytochemistry was carried out based on Treas and Evans method of 1987. The acute toxicity study (LD50) was carried based on Lorke's 1983 method. Convulsion was induced using maximum electric shock (MEST), pentylenetetrazole(PTZ), strychnine and Picrotoxin in the appropriate animal models. Seizures onset time and death time were used as successful induction of convulsion while prolongations of these features were taken as anticonvulsant activity. Results where possible, were statistically analyzed using SPSS-16.0 version.ResultsThe LD50was got at 1118.003mg/kg (IP) in mice using Lorke's 1983 method. Fractionated extract of Crinum jagus exhibited dose dependent antiseizure against MEST induced seizure (P<0.001) and comparable to that of phenytoin, a standard anti generalized tonic-clonic seizure. There were also observable antiseizure activity of the fractionated extracts against PTZ, strychnine and Picrotoxin induced seizure and comparable to their standard corresponding antiseizures.ConclusionsWe conclude that the bulbs of Crinum jagus possess proven broad spectrum antiseizure and perhaps antiepileptogenic activity thus justifies its use in traditional medicine. Clinical trial in man is recommended. 相似文献
994.
Mancuso DJ; Kroner PA; Christopherson PA; Vokac EA; Gill JC; Montgomery RR 《Blood》1996,88(7):2559-2568
This report examines the genetic basis of a variant form of moderately severe von Willebrand disease (vWD) characterized by low plasma von Willebrand factor antigen (vWF:Ag) levels and normal multimerization, typical of type 1 vWD, but disproportionately-low agonist-mediated platelet-binding activity. We identified an in-frame deletion in vWF exon 28 in three generations of affected family members, who are heterozygous for this mutation. The deletion of nucleotides 4,173-4,205 results in the loss of amino acids Arg629-Gln639 in the Cys509-Cys695 loop of the A1 domain in mature vWF. The secreted mutant vWF showed a normal multimeric profile but did not bind to platelets in the presence of optimal concentrations of either ristocetin or botrocetin. The mutant vWF also failed to interact with heparin, and with vWF monoclonal antibody AvW3, which blocks the binding of vWF to GPlb. In addition, mutant vWF showed reduced secretion from transfected cells concomitant with increased intracellular levels. These results confirm that the deletion is the genetic defect responsible for the reduced interaction of vWF with platelets. We have designated this new variant type 2M:Milwaukee-1 vWD. Our analysis suggests that the potential frequency of this phenotype in individuals diagnosed with type 1 vWD is about 0.5%. 相似文献
995.
KS MacDowell JR Caso D Martín-Hernández JL Madrigal JC Leza B García-Bueno 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(3)
Background:
Alterations in the innate immune/inflammatory system have been proposed to underlie the pathophysiology of psychotic disease, but the mechanisms implicated remain elusive. The main agents of the innate immunity are the family of toll-like receptors (TLRs), which detect circulating pathogen-associated molecular patterns and endogenous damage-associated molecular patterns (DAMPS). Current antipsychotics are able to modulate pro- and anti-inflammatory pathways, but their actions on TLRs remain unexplored.Methods:
This study was conducted to elucidate the effects of paliperidone (1mg/Kg i.p.) on acute (6 hours) and chronic (6 hours/day during 21 consecutive days) restraint stress–induced TLR-4 pathway activation and neuroinflammation, and the possible mechanism(s) related (bacterial translocation and/or DAMPs activation). The expression of the elements of a TLR-4-dependent proinflammatory pathway was analyzed at the mRNA and protein levels in prefrontal cortex samples.Results:
Paliperidone pre-treatment prevented TLR-4 activation and neuroinflammation in the prefrontal cortices of stressed rats. Regarding the possible mechanisms implicated, paliperidone regulated stress-induced increased intestinal inflammation and plasma lipopolysaccharide levels. In addition, paliperidone also prevented the activation of the endogenous activators of TLR-4 HSP70 and HGMB-1.Conclusions:
Our results showed a regulatory role of paliperidone on brain TLR-4, which could explain the therapeutic benefits of its use for the treatment of psychotic diseases beyond its effects on dopamine and serotonin neurotransmission. The study of the mechanisms implicated suggests that gut-increased permeability, inflammation, and bacterial translocation of Gram-negative microflora and HSP70 and HGMB1 expression could be potential adjuvant therapeutic targets for the treatment of psychotic and other stress-related psychiatric pathologies. 相似文献996.
Teixido M; Font J; Reverter JC; Cervera R; Tassies D; Ingelmo M; Escolar G; Ordinas A 《Rheumatology (Oxford, England)》1997,36(1):113-116
We studied anti-beta 2-glycoprotein I antibodies (a beta 2GPI) in
autoimmune disease patients to evaluate their relationship to clinical
findings. Seventy-nine systemic lupus erythematosus (SLE) patients [44 with
antiphospholipid antibodies (aPL)], 21 with primary antiphospholipid
syndrome (APS), eight asymptomatic individuals with aPL and 60 controls
were studied. Sixteen SLE patients (14 with aPL and two without aPL) and
six with primary APS had a beta 2GPI. A significant relationship was found
between a beta 2GPI and aPL (P < 0.01). In SLE, a significant
correlation was found between previous thrombosis or thrombocytopenia and a
beta 2GPI or a beta 2GPI + aPL, but not between fetal losses and a beta
2GPI. These data suggest that a beta 2GPI may be useful in the study of
APS.
相似文献
997.
Fibronectin is a major component of the extracellular matrix of adherent layers of human long-term marrow cultures where it may stabilize the extracellular matrix network and provide adhesion sites for primitive hemopoietic cells. This study was devised to analyze the role of adherent cell populations in fibronectin synthesis, matrix assembly, and degradation. In cultures performed under the conditions described by Gartner and Kaplan, immunoprecipitation after metabolic labeling showed that adherent cells synthesized a fibronectin variant comprising the EDa domain and lacking the EDb one. Vascular smooth muscle-like stromal cells were the cell subset responsible for this synthesis. Once synthesized by stromal cells, EDa+fibronectin was secreted into the supernatant and incorporated into the extracellular matrix. The cumulation in the extracellular matrix was predominant by weeks 5 and 6 of culture, when a decrease in the stromal cell intracytoplasmic content of fibronectin was observed. Stromal cells from a transformed cell line, L2Ori-, were also able to synthesize the EDa+fibronectin variant, although for these cells the assembly into the extracellular matrix was partly impaired. Besides stromal cells, other cell types participated in fibronectin synthesis: early-adhering granulomonocytic cells and macrophages appearing later in culture were able to synthesize an EDa-, EDb- fibronectin variant, clearly distinct from the EDa+ variant produced by stromal cells. Studies on cultures in which macrophage growth was stimulated at the expense of stromal cells by adding granulocyte-macrophage colony-stimulating factor (50 ng/mL) to the culture medium showed a striking decrease in amounts of fibronectin measured in the adherent layer. This decrease was caused by a lack of incorporation of fibronectin in the extracellular matrix, disclosing a major difference between stromal cells and macrophages in terms of matrix assembly. This study confirms the similarity between stromal cells and vascular smooth muscle cells, because in vivo subendothelial intimal aortic smooth muscle cells and cultured smooth muscle cells from the aortic media express the EDa+, EDb- fibronectin variant. Furthermore, our results suggest that the level of fibronectin in adherent layers is regulated by stromal cells and macrophages. The balance between these two cell populations may therefore be crucial for the local control of hemopoiesis by regulating the extracellular fibronectin available for the adhesion of hematopoietic cells. Our data indicate that it may be essential to study the adhesion of stem cells to EDa+, EDb- fibronectin instead of EDa-, EDb- soluble fibronectin, as found in human plasma. 相似文献
998.
Presence of Epstein-Barr virus in extranodal T-cell lymphomas: differences in relation to site 总被引:5,自引:2,他引:5
de Bruin PC; Jiwa M; Oudejans JJ; van der Valk P; van Heerde P; Sabourin JC; Csanaky G; Gaulard P; Noorduyn AL; Willemze R 《Blood》1994,83(6):1612-1618
T-cell lymphomas with similar morphology but with different sites of origin have a different clinical behavior. The theoretical explanation for this finding originates from the hypothesis that non-Hodgkin's lymphomas (NHLs) are neoplastic equivalents of immunological reactions involving tissue-restricted lymphocytes. This hypothesis also implies that T-NHLs originating from different sites differ in their genesis, and thus may differ in oncogen expression, expression of adhesion molecules, or presence of certain DNA/RNA viral sequences. Therefore, we have investigated in T-cell lymphomas with similar morphology originating from different sites, ie, nose (n = 5; all pleomorphic small- or medium- and large-cell T-cell lymphomas [PTL]), skin (PTL, n = 6; anaplastic large-cell [ALCL], n = 11), gut (PTL, n = 8; ALCL, n = 4), and lung (PTL, n = 6), the presence of Epstein-Barr virus (EBV) at the DNA, RNA (EBER 1 and EBER 2), and protein level (LMP-1). A double- staining technique was used to detect EBER 1/2, LMP-1, and differentiation markers at the single-cell level. High numbers of EBER 1/2-positive tumor cells (> 100 per medium power field [mpf]) were found in five of five nasal T-cell lymphomas, none of 17 primary cutaneous T-cell lymphomas, one of 12 gastrointestinal T-cell lymphomas (ALCL), and two of six pulmonary T-cell lymphomas. These lymphomas are therefore called EBV-associated lymphomas. In contrast to our earlier findings in lymph nodes, no extranodal lymphomas were found, with only a few EBV-positive tumor cells. Five gastrointestinal cases positive for EBV by polymerase chain reaction (PCR) showed that EBER 1/2 was only found in sporadic nonneoplastic, ie, reactive lymphocytes. Angiocentricity was present in 18 PTL and one ALCL, but not associated with the presence of EBV. These results indicate that the presence of EBV in extranodal T-cell lymphomas is site-restricted and argues for a different pathogenesis of T-cell lymphomas with similar morphology but originating from different sites. The presence of EBV in most tumor cells in these EBV-associated lymphomas suggests that when present, EBV might be important in the pathogenesis of these lymphomas. 相似文献
999.
OBJECTIVE: To estimate physical activity energy expenditure (AEE) in groups of free living infants in the first year of life. DESIGN: Mixed longitudinal study of 124 healthy infants, using 232 estimations of AEE made between 1.5 and 12 months. Infants studied at more than one time point were treated as new cross sectional data points. Total energy expenditure and body composition were estimated using doubly labelled water. Sleeping metabolic rate was predicted from weight. RESULTS: AEE increased from 5% of energy intake at 1.5 months to 34% at 12 months. Growth costs declined by 90%, but metabolisable intake by only 20%, over the same period. CONCLUSIONS: Energy is increasingly diverted from growth to activity during infancy. Values for AEE may aid in estimating energy requirements of groups factorially. Further work is required, however, on individual variability in AEE, and on the effects of disease, hospitalisation, surgery, and malnutrition. 相似文献
1000.
R Brauner M Fontoura JM Zucker A Devergie JC Souberbielle C Prevot-Saucet J Michon E Gluckman C Griscelli A Fischer 《Archives of disease in childhood》1993,68(4):458-463
This study analyses the growth and the growth hormone secretion of children given various conditioning protocols before bone marrow transplantation (BMT). Twenty nine children (14 boys, 15 girls) given BMT were classified according to their conditioning protocol: total body irradiation (TBI) given as a single exposure of 10 Grays (Gy, group I, 11 cases), or 8 Gy (group II, four cases), 12 Gy given as six fractionated doses (Group III, seven cases), or chemotherapy alone (group IV, seven cases). The arginine-insulin stimulated growth hormone peak, 2-7.5 years after BMT, was > 10 micrograms/l in all patients except four from group I (6.9-8.9 micrograms/l). A second growth hormone secretion evaluation was performed in 10 group I patients because of persistent low growth velocity despite a normal growth hormone peak. There were no significant changes in the mean (SEM) stimulated growth hormone peak (18.4 (2.2) v 20.1 (3.6) micrograms/l) at 3 (0.3) to 5.2 (0.6) years after BMT. The sleep growth hormone peaks and concentrations (n = 6) were normal. The mean cumulative height changes (SD) during the three years after BMT were: -1.4 (0.2) in group I, -0.1 (0.4) in group II, -0.4 (0.2) in group III, and 1.5 (0.5) in group IV; this was significant in groups I and IV. The final heights of two monozygotic twins (BMT donor and recipient) had differed by 17.5 cm, despite them both having normal growth hormone peaks and puberty. Eight patients, treated for congenital immune deficiency syndrome, were growth retarded at the time of BMT. Of these, only those conditioned by chemotherapy alone had significant catch up growth (2(0.6)SD) while those conditioned by a single Gy exposure did not (0(0.4)SD). It is concluded that the total radiation dose is critical for growth evolution, as is the fractionation schedule. For the TBI doses and the interval since BMT studied, there was no correlation between growth hormone peak and the height loss. The rapidity of decreased growth velocity after TBI and the comparison between the monozygotic twins suggest that radiation induced skeletal lesions are partly responsible for the decreased growth. 相似文献