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81.
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Breast and axillary tissue MR imaging: correlation of signal intensities and relaxation times with pathologic findings 总被引:1,自引:0,他引:1
We tested a variety of inversion-recovery (IR) and spin-echo (SE) sequences by imaging the breast masses of 22 patients before surgery and 23 tissue specimens with magnetic resonance (MR) imaging at 0.6 T to determine the most effective pulse sequences to evaluate breast disease. An SE pulse sequence using a long repetition time (TR) of 1,600 msec and a long echo time (TE) of 90 msec was found to be the most sensitive in depicting carcinoma in the excised tissue specimens, with all of the carcinomas (n = 15) demonstrating irregular areas of higher signal intensity (SI) than that of the adjacent fat. However, only five of 11 breast carcinomas present in the preoperative patients produced a higher SI than that produced by fat on the same T2-weighted sequence. Five of the remaining six carcinomas in the preoperative patients appeared as localized distortions of fibroductular architecture on both T2-weighted SE and IR sequences. In axillary tissue specimens, both metastatic carcinoma and hyperplastic lymph nodes produced a high SI on T2-weighted SE sequences. However, metastatic carcinoma had a significantly longer T2 relaxation time than did hyperplastic lymph nodes. 相似文献
84.
Enhancement of the hypothermic response of mice to delta-9-tetrahydrocannabinol by subhypothermic doses of chlorpromazine and phentolamine 总被引:1,自引:0,他引:1
Pretreatment with subhypothermic doses of chlorpromazine, given directly into the IIIrd cerebral ventricle via a chronically implanted cannula (50 micrograms) or subcutaneously (0.75 mg/kg), was found to enhance the hypothermic response to delta-9-tetrahydrocannabinol (THC: 5 20 mg/kg i.p.) in unrestrained adult male MF1 mice, kept at 22 degrees C. Subcutaneous pretreatment with a subhypothermic dose of phentolamine (30 mg/kg) had a similar effect, whereas pretreatment with desipramine (10 mg/kg s.c.), mepyramine (2.3 and 11.5 mg/kg s.c.), methysergide (2 mg/kg s.c.), pimozide (1 and 5 mg/kg s.c.) or lignocaine (50 mg/kg s.c.), had no effect. Intracerebroventricular pretreatment with phentolamine was also without effect and it is concluded that this drug interacts with THC at some site located outside the brain. Since, in mg/kg terms, chlorpromazine was more potent in enhancing THC-induced hypothermia when given subcutaneously than when injected into the IIIrd ventricle, it too may interact with THC at a peripheral site. Indeed, chlorpromazine and phentolamine may both increase the hypothermic response to THC by antagonizing alpha-adrenoceptors on cutaneous blood vessels, thereby decreasing the capacity of animals to minimise peripheral blood flow by vasoconstriction. Alternatively, since the distribution of chlorpromazine within the brain may well have been less efficient after intraventricular than after subcutaneous injection, the possibility remains that chlorpromazine interacted centrally with THC. 相似文献
85.
86.
K Hedley MB BS MRCGP P Tooley MBBS MRCGP H Williams MB BCH FRCGP 《International journal of clinical practice》1990,44(4):131-135
A double-blind comparative study between 1 % hydrocortisone cream and a combination of 1% hydrocortisone cream and 2% miconazole cream has highlighted some of the problems with this type of research in general practice. The collection of adequate patient numbers within a predefined time scale proved a major problem. However, the study demonstrated the safety and efficacy of both these preparations in the treatment of intertrigo. 相似文献
87.
Frank Friedlos Panos Lehouritis Lesley Ogilvie Douglas Hedley Lawrence Davies David Bermudes Ivan King Jan Martin Richard Marais Caroline J Springer 《Clinical cancer research》2008,14(13):4259-4266
PURPOSE: We engineered the oncolytic Salmonella typhimurium-derived bacterium VNP20009 as a vector to target delivery to tumors of the prodrug-activating enzyme carboxypeptidase G2 (CPG2) and to show enhanced antitumor efficacy on administration of different prodrugs. EXPERIMENTAL DESIGN: We characterized CPG2 expression in vectors by immunoblotting, immunofluorescence, and enzyme activity. We assessed prodrug activation by high-performance liquid chromatography. Target human tumor cell and bacterial vector cell cytotoxicity was measured by flow cytometry and colony-forming assays. Therapy was shown in two human tumor xenografts and one mouse allograft with postmortem analysis of bacterial and CPG2 concentration in the tumors. RESULTS: CPG2 is expressed within the bacterial periplasm. It activates prodrugs and induces cytotoxicity in human tumor cells but not in host bacteria. Following systemic administration, bacteria multiply within xenografts reaching 2 x 10(7)/g to 2 x 10(8)/g at 40 days postinoculation. The concentration of CPG2 in these tumors increases steadily to therapeutic levels of 1 to 6 units/g. The bacteria alone reduce the growth of the tumors. Subsequent administration of prodrugs further reduces significantly the growth of the xenografts. CONCLUSIONS: The bacteria multiply within tumors, resulting in a selective expression of CPG2. The CPG2-expressing bacteria alone reduce the growth of tumors. However, in the presence of prodrugs activated by CPG2, this oncolytic effect is greatly increased. We conclude that bacterial oncolytic therapy, combined with CPG2-mediated prodrug activation, has great potential in the treatment of a range of cancers. 相似文献
88.
R C Stein M Dowsett J Davenport A Hedley H T Ford J C Gazet R C Coombes 《Cancer research》1990,50(5):1381-1384
Thirty-one postmenopausal women with advanced breast cancer have been treated with the nonsteroidal competitive aromatase inhibitor CGS 16949A at p.o. doses of 0.3, 1, and 2 mg twice a day. All patients were assessed for response. Five patients, all treated with 1 mg twice daily, had objective evidence of response (two complete responses and three partial responses); disease stabilized in 17 patients. Minor side effects were reported by ten patients. Two further patients treated with 2 mg twice a day experienced persistent nausea which improved after dose reduction, and one patient, treated with 0.3 mg twice daily, developed a vasculitic rash requiring discontinuation of CGS 16949A. Estradiol levels measured in 24 patients were significantly suppressed 2 wk after starting CGS 16949A treatment at all doses used. Treatment with 2 mg twice a day lowered estradiol levels to a mean of 29% of pretreatment values which was significantly lower than the corresponding figure of 57% for patients treated with 0.3 mg twice daily. Aldosterone levels were significantly lowered below pretreatment values by the 1- and 2-mg twice daily doses. No clinically apparent cases of adrenocortical insufficiency occurred, although small changes in serum electrolyte levels were noted. The results indicate that CGS 16949A is an effective aromatase inhibitor, requiring further evaluation in the treatment of advanced breast cancer. The optimal dose is likely to be 1 mg twice a day. 相似文献
89.
90.
Nhu-An Pham Joerg Schwock Vladimir Iakovlev Greg Pond David W Hedley Ming-Sound Tsao 《BMC cancer》2008,8(1):43