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101.
Comparison of mucosal and systemic humoral immune responses after transcutaneous and oral immunization strategies 总被引:5,自引:0,他引:5
In order to compare the ability of transcutaneous and oral immunization strategies to induce mucosal and systemic immune responses, we inoculated mice transcutaneously with cholera toxin (CT) or the non-toxic B subunit of cholera toxin (CtxB), or orally with Peru2(pETR1), an attenuated vaccine strain of Vibrio cholerae expressing CtxB. In addition, we also evaluated dual immunization regimens (oral inoculation with transcutaneous boosting, and transcutaneous immunization with oral boosting) in an attempt to optimize induction of both mucosal and systemic immune responses. We found that transcutaneous immunization with purified CtxB or CT induces much more prominent systemic IgG anti-CtxB responses than does oral inoculation with a vaccine vector strain of V. cholerae expressing CtxB. In comparison, anti-CtxB IgA in serum, stool and bile were comparable in mice either transcutaneously or orally immunized. Overall, the most prominent systemic and mucosal anti-CtxB responses occurred in mice that were orally primed with Peru2(pETR1) and transcutaneously boosted with CT. Our results suggest that combination oral and transcutaneous immunization strategies may most prominently induce both mucosal and systemic humoral responses. 相似文献
102.
M ODowd T Geoghegan PL Munk G McAuley WC Torreggiani 《Journal of Medical Imaging and Radiation Oncology》2006,50(4):386-388
Osseous haemophilic pseudotumours are uncommon. The commonest sites of involvement are the femur and the pelvis. Trauma is the initiating factor in most reported cases and repeated bleeding into the lesion contributes to their growth. Most lesions grow slowly and are often asymptomatic. Complications include massive haemorrhage, infection and pathological fracture. We present an extremely unusual presentation where a large haemophilic pseudotumour of the pelvis extended to impinge the adjacent colon, resulting in large bowel obstruction. 相似文献
103.
Objective : To evaluate the efficacy of biliary‐enteric bypass in the palliation of malignant hilar biliary obstruction. Materials and Methods : Records of 19 patients from 1995 to 1998 were reviewed. There were 13 patients with cholangiocarcinoma and 6 patients with carcinoma of the gallbladder. Single biliary‐enteric bypass had been performed in 13 of the patients; the rest had more than one biliary‐enteric anastomosis. Results : The 30‐day mortality was 21% (4/19 patients). Bile leakage occurred in 2 patients, leading, in both, to fatality. Excluding the 30‐day mortality, the median survival of patients with carcinoma of the gallbladder and cholangiocarcinoma was 116 days (43–200) and 202 days (47–1207), respectively. The mean hospital stay was 31 days (13–59) and all patients were discharged with their symptoms relieved and a drop in bilirubin of at least two‐thirds their pre‐operative level. The late complication rate was 26.7% (4/15 patients). Conclusion : Biliary‐enteric bypass is effective in the palliation of symptoms of patients suffering from unresectable hilar biliary obstruction, although it carries considerable mortality and morbidity. Stenting, rather than surgery, should be considered for patients with unresectable gallbladder cancer. 相似文献
104.
NA Bridges JA Christopher PC Hindmarsh CG Brook 《Archives of disease in childhood》1994,70(2):116-118
The aetiology of 197 girls and 16 boys presenting with sexual precocity was reviewed. Ninety one girls and four boys had central precocious puberty (M:F 23:1); a cause was identified in all the boys but in only six girls. All boys with precocious puberty need detailed investigation; in girls investigation should be based on clinical findings, particularly the consonance of puberty. 相似文献
105.
Anticancer efficacy of the irreversible EGFr tyrosine kinase inhibitor PD 0169414 against human tumor xenografts 总被引:4,自引:0,他引:4
Vincent PW Bridges AJ Dykes DJ Fry DW Leopold WR Patmore SJ Roberts BJ Rose S Sherwood V Zhou H Elliott WL 《Cancer chemotherapy and pharmacology》2000,45(3):231-238
Purpose: The involvement of the EGF receptor (EGFr) family of receptors in cancers suggests that a selective inhibitor of the tyrosine
kinase activity of the EGFr family could have a therapeutic effect. PD 0169414, an anilinoquinazoline, is a potent irreversible
inhibitor of the EGFr family tyrosine kinase activity with IC50 values of 0.42 nM against the isolated EGF receptor, and 4.7 nM and 22 nM against EGF- and heregulin-mediated receptor phosphorylation in A431 and MDA-MB-453 cells, respectively. Methods and Results: Oral administration of 260 mg/kg per day PD 0169414 for 15 days to animals bearing advanced-stage A431 epidermoid carcinoma
produced a 28.2-day delay in tumor growth and resulted in three complete and three partial tumor regressions in six animals.
Toxicity at this dose level was limited to <6% loss of initial body weight. Doses of 160 and 100 mg/kg per day produced tumor
growth delays of 29.5 and 20.9 days and two and one complete regressions in six animals, respectively. Subcutaneous, intraperitoneal,
and oral routes of administration have also shown in vivo antitumor activity of PD 0169414 in a panel of human tumor xenografts.
Responsive tumor lines include A431 (human epidermoid carcinoma), H125 (NSCL carcinoma), MCF-7 and UISO-BCA1 (human breast
carcinoma), and SK-OV-03 (human ovarian carcinoma). The therapeutic effect ranged from delayed tumor growth (6.4 days delayed
tumor growth for 14 days of treatment) to tumor regressions (32.2 days delayed tumor growth and five partial regressions in
six animals) in these model systems. Conclusion: PD 0169414 is a specific, irreversible inhibitor of EGFr family tyrosine kinases with significant in vivo activity against
a variety of relevant human tumor xenografts.
Received: 19 May 1999 / Accepted: 11 August 1999 相似文献
106.
C W Caldwell A J Bridges S E Walker K L Smarr R J Reichert S K Anderson J E Hewett J C Parker 《Clinical immunology and immunopathology》1992,63(3):237-244
The purpose of this study was to determine if patients with rheumatoid arthritis (RA) exhibited unique patterns of peripheral blood lymphocyte (PBL) subsets in comparison to patients with osteoarthritis (OA) and, further, if such differences related to disease activity or nondisease factors. Data from 63 RA patients and 47 OA patients revealed that the RA patients had lower absolute numbers of CD2+ and CD4+ lymphocytes. Small differences also were found in selected B-cell subsets and subsets of lymphocytes expressing CD16 and/or CD57 antigens. Further analysis revealed that these differences were due primarily to the effects of cytotoxic medications in the RA group. However, there were also alterations in some subsets independent of medication groups. PBL subsets in RA patients did not relate to chronic low-dose prednisone or measures of disease activity. This study demonstrated the need to control carefully for variables such as age and medication in immunophenotypic investigations of RA. 相似文献
107.
In the design of surfaces which absorb waves, the impedance boundary condition is used as an effective means of diminishing the reflection. In this paper, we use the geometrical optics method to approximate the optimal impedance value which minimizes the reflected field for the scalar wave equation with a monochromatic source. Our treatment yields good results for optimal impedance in the asymptoticity region of the geometrical optics solution. 相似文献
108.
The binding of a homologous series of 2-n-alkylbenzimidazoles to rat hepatic microsomal cytochrome P-450 has been examined. Type I, Type RI and mixed Type I/RI spectra were observed with control, phenobarbitone or 20-methylcholanthrene-induced microsomal preparations. In general short chain (C1-C4) substituted compounds elicited Type RI spectra, whereas C5-C9 substituted benidazoles gave rise to Type RI/I or Type I spectra. The type of binding spectrum observed was dependent upon the substrate concentration, the source of microsomes and the length of the substituent alkyl chain. As the lipophilic character of the substituent was increased a corresponding increase in Type I nature was noted. However, an optimal chain length of C7-C8 carbon atoms was observed for Type I binding; compounds with longer side chains showed a decreased affinity for the Type I site. The apparent spectral binding constants (fs values) for the Type I site (but not the Type RI site) were closely associated with the Ki and I50 values for the inhibition of cytochrome P-450-dependent monooxygenation. From their inhibition properties it seems that even the short chain (C1-C4) substituted benzimidazoles also bind to the Type I site and thus compete for the substrate binding site of cytochrome P-450. 相似文献
109.
110.