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41.
Mathur SR Dahiya S Nayak A Bhatla N Singh MK 《Indian journal of pathology & microbiology》2004,47(3):333-335
We describe the clinicopathological and immunohistochemical findings in five cases of sclerosing stromal tumours of ovary and compare our findings with other reported cases of this uncommon tumour and with fibromas and thecomas which they may mimic. 相似文献
42.
Amrikachi M Krishnan B Finch CJ Shahab I 《Archives of pathology & laboratory medicine》2000,124(10):1502-1505
We present 2 unusual cases of long-standing, extensive reactive lymphadenopathy secondary to Actinomyces infection, 1 of which was also accompanied by Actinobacillus actinomycetemcomitans-Actinomyces complex infection. To our knowledge, histologic features of lymph node involvement by these organisms have not been previously reported in the literature. One patient had extensive cervical, posterior mediastinal, and abdominal lymphadenopathy. The second patient presented with a submandibular mass and cervical lymphadenopathy. Clinical features strongly suggested lymphoma. The histologic examination of the lymph nodes from both patients revealed reactive follicular hyperplasia, marked interfollicular and capsular fibrosis, and multiple interfollicular microabscesses. Characteristic Actinomyces colonies were identified at the center of the microabscesses in deep sections. Cultures were obtained from the lymph nodes of 1 patient, and were positive for A actinomycetemcomitans. Both patients had poor dental hygiene. Lymphadenopathy subsided with antibiotic therapy and appropriate dental care. 相似文献
43.
44.
Inhibition of Prostate Cancer Cell Colony Formation by the Flavonoid Quercetin Correlates with Modulation of Specific Regulatory Genes
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Hari Krishnan Nair Kesava V. K. Rao Ravikumar Aalinkeel Supriya Mahajan Ram Chawda Stanley A. Schwartz 《Clinical and Vaccine Immunology : CVI》2004,11(1):63-69
The natural product quercetin is a flavonoid found in many fruits and vegetables. Previous research has shown that quercetin has antitumor, anti-inflammatory, antiallergic, and antiviral activities. In the present investigation we studied the effect of quercetin on the ability of prostate cancer cell lines with various degrees of aggressive potential to form colonies in vitro. Specifically, we examined the molecular mechanisms underlying this effect, including the expression of cell cycle and tumor suppressor genes as well as oncogenes. We observed that quercetin at concentrations of 25 and 50 μM significantly inhibited the growth of the highly aggressive PC-3 prostate cancer cell line and the moderately aggressive DU-145 prostate cancer cell line, whereas it did not affect colony formation by the poorly aggressive LNCaP prostate cancer cell line or the normal fibroblast cell line BG-9. Using the gene array methodology, we found that quercetin significantly inhibited the expression of specific oncogenes and genes controlling G1, S, G2, and M phases of the cell cycle. Moreover, quercetin reciprocally up-regulated the expression of several tumor suppressor genes. In conclusion, our results demonstrate that the antitumor effects of quercetin directly correlate with the aggressive potential of prostate cancer cells and that the mechanism(s) of quercetin-mediated antitumor effects may involve up-regulation of tumor suppressor genes and reciprocal down-regulation of oncogenes and cell cycle genes. The results of these studies provide a scientific basis for the potential use of flavonoids as nutraceuticals in the chemoprevention of cancer. 相似文献
45.
Inhibition of prostate cancer cell colony formation by the flavonoid quercetin correlates with modulation of specific regulatory genes 总被引:4,自引:0,他引:4
Nair HK Rao KV Aalinkeel R Mahajan S Chawda R Schwartz SA 《Clinical and diagnostic laboratory immunology》2004,11(1):63-69
The natural product quercetin is a flavonoid found in many fruits and vegetables. Previous research has shown that quercetin has antitumor, anti-inflammatory, antiallergic, and antiviral activities. In the present investigation we studied the effect of quercetin on the ability of prostate cancer cell lines with various degrees of aggressive potential to form colonies in vitro. Specifically, we examined the molecular mechanisms underlying this effect, including the expression of cell cycle and tumor suppressor genes as well as oncogenes. We observed that quercetin at concentrations of 25 and 50 micro M significantly inhibited the growth of the highly aggressive PC-3 prostate cancer cell line and the moderately aggressive DU-145 prostate cancer cell line, whereas it did not affect colony formation by the poorly aggressive LNCaP prostate cancer cell line or the normal fibroblast cell line BG-9. Using the gene array methodology, we found that quercetin significantly inhibited the expression of specific oncogenes and genes controlling G(1), S, G(2), and M phases of the cell cycle. Moreover, quercetin reciprocally up-regulated the expression of several tumor suppressor genes. In conclusion, our results demonstrate that the antitumor effects of quercetin directly correlate with the aggressive potential of prostate cancer cells and that the mechanism(s) of quercetin-mediated antitumor effects may involve up-regulation of tumor suppressor genes and reciprocal down-regulation of oncogenes and cell cycle genes. The results of these studies provide a scientific basis for the potential use of flavonoids as nutraceuticals in the chemoprevention of cancer. 相似文献
46.
Evaluation of cell mediated immune responses in untreated cases of leprosy 总被引:3,自引:8,他引:3
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G P Talwar A D Krishnan V L Mehra E A Blum J M Pearson 《Clinical and experimental immunology》1972,12(2):195-203
Twenty-three leprosy patients have been studied in an endemic area before institution of chemotherapy. These were comprised of ten lepromatous leprosy, four borderline lepromatous and nine tuberculoid leprosy cases on basis of clinical features, bacteriological and marphological indices. Histopathology of skin biopsies classified two as truly polar lepromatous leprosy (LL) and three as polar tuberculoid (TT), while the remaining eighteen were at various stages of evolution towards lepromatous or tuberculoid end of the spectrum. All lepromatous and borderline leprosy patients showed negative delayed hypersensitivity reaction with lepromin, but six out of fourteen patients in this category gave positive reaction with PPD. Blast transformation with PHA of peripheral leucocytes from all cases of lepromatous leprosy cultured in standard AB serum was depressed in comparison with cells from normal controls. 3H-thymidine incorporation in DNA of leucocytes in presence of leprolin was lower in cells of lepromatous leprosy group as compared to those from tuberculoid and borderline cases. There was lack of production of macrophage aggregation factor in all except one case of lepromatous leprosy while the test for this factor was positive for most of the tuberculoid leprosy patients. The homing characteristics of lymphocytes tagged with 51Chromium into liver and spleen of test mice were altered from the normal pattern in a large number of leprosy cases. 相似文献
47.
Pethannan Subramanian Krishnan Venkatarao 《Macromolecular chemistry and physics.》1983,184(12):2447-2455
New aromatic polyamides containing azomethine groups in the backbone and also having different linking groups like ? CH2? , ? CH2? CH2? , and ? O? were synthesized by reacting 4,4′-[1,4-phenylenebis(methylidynenitrilo)]dibenzoyl dichloride (2) with some diamines 1a – d, 4, and 6 by the low temperature solution polycondensation method. The physical, spectral, and thermal properties of the synthesized polyamides were investigated. The effect of the nature of different linking groups on the properties of these aromatic polymides was explored by comparing their spectral and thermal data. 相似文献
48.
49.
Masquelier B Bhaskaran K Pillay D Gifford R Balestre E Jørgensen LB Pedersen C van der Hoek L Prins M Balotta C Longo B Kücherer C Poggensee G Ortiz M de Mendoza C Gill J Fleury H Porter K;CASCADE Collaboration 《Journal of acquired immune deficiency syndromes (1999)》2005,40(5):505-511
OBJECTIVES: To examine factors influencing the rate of transmitted drug resistance (TDR) among seroconverters, with particular emphasis on 3 widely used genotypic drug resistance algorithms. METHODS: The study used data from CASCADE (Concerted Action on Seroconversion to AIDS and Death in Europe), a collaboration of seroconverter cohorts in Europe and Canada. Genotypic resistance data were derived within 18 months of the last seronegative test or date of laboratory evidence of acute infection and before the initiation of antiretroviral therapy. The Stanford algorithm was used to analyze each individual's nucleotide sequence. A multivariate logistic model was used to assess independent relationships between the presence of TDR and exposure category, sex, age at seroconversion, and year of seroconversion. The paper also describes 3 alternative definitions of resistance: the Stanford algorithm, the key resistance mutations defined by the International AIDS Society, and the Agence Nationale de Recherches sur le Sida (ANRS) algorithm. RESULTS: Forty-five of 438 patients (10.3%) seroconverting between 1987 and 2003 were infected with a drug-resistant HIV-1 variant. Forty patients (9.1%) showed resistance mutations to only 1 class of antiretroviral drugs, 2 (0.5%) to 2 classes, and 3 (0.7%) to 3 classes of antiretroviral therapy. It was suggested that individuals seroconverting later in calendar time were more likely to have TDR (relative risk 3.89 and 95% CI: 0.84 to 18.02, and relative risk 4.69 and 95% CI: 1.03 to 21.31, for 1996-1999 and 2000-2003, respectively, compared with pre-1996; P trend = 0.08). This trend was apparent regardless of the definition of TDR used. The total estimated proportion of individuals with TDR varied between 10.3% and 15.5% according to which definition was used. CONCLUSIONS: Evidence was found for the rise of TDR over time. A specific definition of what constitutes TDR rather than a simple list of mutations is needed. 相似文献
50.
Physiological and Psychological Effects of Delivering Medical News Using a Simulated Physician–Patient Scenario 总被引:1,自引:0,他引:1
Cohen L Baile WF Henninger E Agarwal SK Kudelka AP Lenzi R Sterner J Marshall GD 《Journal of behavioral medicine》2003,26(5):459-471
We examined the acute stress response associated with having to deliver either bad or good medical news using a simulated physician–patient scenario. Twenty-five healthy medical students were randomly assigned to a bad medical news (BN), a good medical news (GN), or a control group that read magazines during the session. Self-report measures were obtained before and after the task. Blood pressure and heart rate were measured throughout the task period. Four blood samples were obtained across the task period. The BN and GN tasks produced significant increases in self-reported distress and cardiovascular responses compared with the control group. There was also a significant increase in natural killer cell function 10 min into the task in the BN group compared with the control group. The BN task was also somewhat more stressful than the GN task, as shown by the self-report and cardiovascular data. These findings suggest that a simulated physician–patient scenario produces an acute stress response in the physician, with the delivery of bad medical news more stressful than the delivery of good medical news. 相似文献