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1.
目的:建立鼠巨细胞病毒(MCMV)感染C57BL/6小鼠急性肝炎模型并对其感染特点进行分析及鉴定。方法:将24 只C57BL/6小鼠随机分为阴性对照组(n =12)及病毒感染组(n =12),病毒感染组腹腔注射1.0×106 PFU(200 μL)MCMV悬液,阴性对照组注射等体积小鼠胚胎成纤维细胞(MEF)悬液。于感染后第3天和第7天取外周血分离血清检测谷丙转氨酶(ALT)及谷草转氨酶(AST)。同时进行肝组织病毒分离、组织病理学及MCMV IE和M55基因、细胞因子白细胞介素-6(IL-6)、白细胞介素-1β(IL-1β)、肿瘤坏死因子α(TNF-α)的检测。结果:病毒感染组肝组织匀浆病毒分离均为阳性,肝炎发生率为100%。在感染后第3天即发生肝炎病理改变,病毒感染组血清ALT及AST较阴性对照组明显升高(P <0.01);病毒感染组肝脏HE染色第3天可见局灶性炎性细胞浸润及肝脏点灶状坏死,持续至第7天,Ishak评分较阴性对照组明显升高(P <0.01);在感染后第3天病毒感染组肝组织内可检测到MCMV IE及M55基因,且在感染后第7天仍可测得IE基因;感染后第3天及第7天病毒感染组炎性细胞因子IL-6、TNF-α及IL-1β mRNA表达水平明显升高(P <0.05)。 结论:成功建立MCMV感染C57BL/6小鼠急性动物肝炎模型,其感染表现主要集中在急性感染前期。 相似文献
2.
长波紫外线照射对小鼠黑素瘤细胞的影响 总被引:1,自引:0,他引:1
[目的]研究不同剂量UVA照射对体外培养B_16小鼠黑素瘤细胞的形态、增殖率、黑素含量和酪氨酸酶活性的影响。[方法]选用B_16小鼠黑素瘤细胞 ,经不同剂量的UVA照射后 ,采用MTT法测定细胞的增殖 ,参照HideyaAndo等的方法测定酪氨酸酶活性和黑素含量。[结果]UVA照射后 ,黑素含量增加 (P<0.01) ,酪氨酸酶活性提高 (P<0.05) ,细胞增殖率上升 ,照射剂量在0.6、1.2、1.8J/cm2时 ,细胞增殖率的变化有显著性 (t=2.495、2.645、3.081,均为P<0.05)。[结论]随着照射剂量的增加 ,黑素含量增加 ,酪氨酸酶活性提高 ,细胞的增殖率增加 ,但UVA的促黑素瘤细胞增殖作用是有限的 相似文献
3.
Our new finding of de novo synthesis and secretion of C3 by both murine peritoneal macrophages and polymorphonuclear leukocytes (PMN) was confirmed by the incorporation of [35S]methionine into C3 molecules and their complete inhibition by cycloheximide. The methods of secretion of C3 from these two types of cells were compared by examining the C3 contents in their culture supernatants. Completely different modes of secretion were observed, i.e. although macrophages synthesize and secrete C3 constitutively, PMN has a mechanism to store the already synthesized C3 in the cell and secrete it in response to stimuli. Protein kinase C (PKC) activators, e.g. 12-O-tetradecanoyl-phorbol 13-acetate, dioctanoyl glycerol, and mezerein, as well as calcium ionophore A23187 stimulate the secretion of C3 from PMN. These results suggest the involvement of PKC and the calmodulin pathway. A very sensitive method for measuring C3 activity was developed which enabled us to show for the first time that C3 secreted by PMN had opsonizing activity and that particles cultured with PMN were phagocytosed effectively. 相似文献
4.
D. A. Basketter E. W. Scholes M. Cumberbatch C. D. Evans I. Kimber 《Contact dermatitis》1992,27(4):209-213
The guinea pig maximization test (GPMT) has proven to be a valuable tool for the identification of the skin sensitization potential of chemicals. The method identifies a hazard which can lead in the EC to compulsory labelling of that chemical. In the present study, data on sulphanilic acid derived from the GPMT has been compared with results from a second guinea pig assay (the cumulative contact enhancement test) and the murine local lymph node assay, both of which require only topical application of chemical. Except for the GPMT, no test identified any sensitizing activity associated with exposure to sulphanilic acid. These latter results are consistent with the experience gained from substantial human exposure in an occupational setting and from which no cases of allergic contact dermatitis to sulphanilic acid have arisen over a 20-year period. In consequence, it is questioned which test protocol in practice has given the more accurate identification of sensitization hazard relevant to man. 相似文献
5.
Murine thymus has been demonstrated to contain both cholinergic receptors and acetylcholinesterase activity. In the present study we have investigated the presence of the enzyme choline acetyltransferase in this organ, which is responsible for the synthesis of acetylcholine. Results reported here demonstrate that (1) an appreciable amount of the enzyme is already present in the thymus on the day of birth; (2) its expression is developmentally regulated; and (3) thymic atrophy, induced in young (2-week-old) and adult (6-week-old) mice by i.p. injection of hydrocortisone for 2 days, is accompanied by significant reduction of choline acetyltransferase activity only in young mice. Altogether these results demonstrate the presence in the murine thymus of functionally relevant markers of the cholinergic system that might interface the interactions between the nervous and immune systems. 相似文献
6.
目的 根据小鼠神经元与T淋巴细胞具有共同抗原Thy-1的特点,利用鼠脑组织制备兔抗鼠T淋巴细胞血清。方法 提取鼠脑组织与弗氏完全佐剂混合,制成油包水乳剂, 免疫2只家兔后,采血,分离血清,用鼠脾淋巴细胞做凝集试验及补体依赖的细胞毒试验确定其活性。结果 制备的抗血清可与鼠脾淋巴细胞发生反应,2只兔抗血清凝集试验的效价分别为1:640及1:1280。抗血清1:320倍稀释后与鼠脾淋巴细胞做补体依赖的细胞毒试验,特异性细胞毒性均为32%。结论 用鼠脑组织制备抗鼠T淋巴细胞血清是一种可行的方法。 相似文献
7.
Jorge C. Nadal Cees J. van Groeningen Herbert M. Pinedo Godefridus J. Peters 《Investigational new drugs》1989,7(2-3):163-172
Summary The effect of leucovorin (LV) given in various doses and schedules on the in vivo antitumor activity and toxicity of 5-fluorouracil (5FU) was studied in two murine colon cancer lines, i.e., Colon 26 (relatively resistant to 5FU) and Colon 38 (5FU sensitive), maintained in Balb-c and C57B1/6 mice, respectively. Mice were treated weekly with 5FU at the maximum tolerated dose, alone and in combination with LV. In Colon 26, neither simultaneous administration of 5FU and LV nor 5FU combined with delayed administration of LV potentiated the antitumor activity of 5FU. LV given twice — 1 hr before (50 mg/kg) and then together (50 mg/kg) with 5FU (100 mg/kg) — gave significantly better delay of tumor growth of both tumor lines than 5FU did alone (100 mg/kg). No differences were found after a total LV dose of 100 or 200 mg/kg. Delayed administration of uridine (3500 mg/kg) allowed the use of higher 5FU doses, which improved the antitumor effect on Colon 26. Systemic toxicity led to moderate weight loss in treated mice, but was comparable for mice treated with 5FU alone or combined with LV. Hematological toxicity consisted of moderate leukopenia (nadir 40%), which was observed with the most active schedule and was less severe than with 5FU alone. This schedule did not cause thrombocytopenia, but after discontinuation the thrombocyte count showed an overshoot. Addition of uridine to this schedule reduced hematological toxicity only slightly. It is concluded that LV potentiated the antitumor activity of 5FU against two solid tumor lines, i.e., a relatively resistant and a sensitive murine colon carcinoma, and that toxicity was moderate.Abbreviations 5FU
5-fluorouracil
- LV
leucovorin (folinic acid, 5-formyl-tetrahydrofolate)
- FdUMP
5-fluoro 2-deoxyuridine 5monophosphate
- TS
thymidylate synthase
- CH2-THF
5-10 methylenetetrahydrofolate
- UR
uridine
- GDF
growth delay factor
- TD
tumor doubling time
- MTD
maximum tolerated dose
- T/C
mean tumor volume of treated mice divided by mean tumor volume of control mice 相似文献
8.
Newman JT Surman SR Riggs JM Hansen CT Collins PL Murphy BR Skiadopoulos MH 《Virus genes》2002,24(1):77-92
A complete consensus sequence was determined for the genomic RNA of human parainfluenza virus type 1 (HPIV1) strain Washington/20993/1964 (HPIV1 WASH/64), a clinical isolate that previously was shown to be virulent in adults. The sequence exhibited a high degree of relatedness to both Sendai virus, a PIV1 virus recovered from mice, and human PIV3 (HPIV3) with regard to cis-acting regulatory regions and protein-coding sequences. This consensus sequence was used to generate a full-length antigenomic cDNA and to recover a recombinant wild-type HPIV1 (rHPIV1). Interestingly, the rHPIV1 could be rescued from full-length antigenomic rHPIV1 cDNA using HPIV3 support plasmids, HPIV1 support plasmids, or a mixture thereof. The replication of rHPIV1 in vitro and in the respiratory tract of hamsters was similar to that of its biologically derived parent virus. The similar biological properties of rHPIV1 and HPIV1 WASH/64 in vitro and in vivo, together with the previous demonstration of the virulence of this specific isolate in humans, authenticates the rHPIV1 sequence as that of a wild-type virus. This rHPIV1 can now be used to study the biological properties of HPIV1 and as a substrate to introduce attenuating mutations for the generation of live-attenuated HPIV1 vaccine candidates.An erratum to this article can be found at 相似文献
9.
We have developed an enzyme-linked immunosorbent assay (ELISA) to measure murine antigen-specific IgG antibodies of defined subclass using precalibrated equivalence dilutions of anti-κ (in the standard) and each anti-IgG subclass-specific polyclonal secondary antibody (in the test sample). The calibration of secondary reagents could be carried out easily with a set of monoclonal antibodies (MoAbs) specific for all IgG subclasses. These MoAbs do not require purification or standardization. In addition the MoAbs can be of different antigenic specificity. Once the equivalence dilutions have been determined, they can be applied in a quantitative ELISA using the same antigen in the standard and sample, and using only one IgG subclass standard for the determination of all the IgG subclasses. The method is easy to standardize for many antigenic systems. It is particularly useful when the only standard available is one standardized MoAb of the appropriate specificity, and it could be adapted to use with standard polyclonal antibodies having a known content of total antigen-specific IgG bearing κ chains but unknown IgG subclass composition. The use of this method to quantitate IgG specific for the capsular polysaccharide of Neisseria meningitidis serogroup B (CpsB) gave highly reproducible measures with an interbatch CV of 5–6% similar for all IgG subclasses and low detection limits ranging from 0.3 ng/well for IgG3 to 0.8 ng/well for IgG2a. The IgG subclass response observed after immunization with live meningococci was mainly IgG2a (74%) and IgG2b (18%). Hyperimmunization modified this IgG distribution to one of mainly IgG3 (62%) and IgG1 (28%) which was maintained in the response to a single immunization 4 weeks later, possibly indicating the generation of resting B cells during continuous stimulation. 相似文献
10.
C Morland J Michael D Adu T Kizaki A J Howie A Morgan N A Staines 《Clinical and experimental immunology》1991,83(1):126-132
The effect of the administration of a xenogeneic anti-idiotype antibody (anti-Id33) to a cross-reactive idiotype (Id33) present on anti-dsDNA antibody was examined in 6-week-old (NZB/NZW) F1 (BWF1) female mice. The administration of anti-Id33 led to a transient reduction in immunoglobulins expressing Id33, followed by a rise at 30 and 34 weeks that was significantly higher than in untreated mice (P less than 0.05). Likewise, anti-dsDNA antibody levels were significantly higher at 10 and 18 weeks than in untreated mice (P less than 0.01). No differences were seen in survival to 40 weeks, proteinuria or the severity of glomerulonephritis. Concurrent administration of cyclosporin A (CyA) with anti-Id33 markedly ameliorated glomerular injury and proteinuria and improved survival. By contrast, glomerular injury, proteinuria and survival were worse in mice treated with cyclophosphamide plus anti-Id33, compared with untreated mice. Neither CyA nor cyclophosphamide treatment, when given with anti-Id33 altered serum levels of anti-dsDNA, anti-ssDNA or Id33+ immunoglobin, compared with untreated mice. The different effects of CyA and cyclophosphamide on T lymphocytes and their discrepant effects on glomerular injury when given with anti-Id33 in this model lead us to postulate a role for T lymphocytes in the glomerular injury of BWF1 lupus. 相似文献