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Akinori Mitsui Midori Yoshizawa Hiromichi Matsumoto Emiko Fukui 《Journal of assisted reproduction and genetics》2009,26(1):35-39
Purpose The effects of reciprocal transplantation of meiosis-II chromosomes between senescent and young mouse oocytes were evaluated
based on pre- and post-implantation development ability of resultant embryos.
Methods Karyoplasts including meiosis-II chromosomes of oocytes from senescent Rockefeller mouse/Ms-Rb(6, 15) females (10 to 12 months,
age-related infertile mice) were transferred into cytoplasts of oocytes from young F1 females (3 to 5 months). Reconstructed oocytes were fertilized in vitro, and then the resultant embryos were cultured in
vitro and transferred to recipient mice.
Results The reconstructed oocytes that consisted of aged-karyoplasts and young-cytoplasts showed significantly improved embryonic
development (from 23.2% to 30.0%) and development to term (from 6.3% to 27.1%, P < 0.05) as compared with the oocytes reconstructed from young-karyoplasts and aged-cytoplasts.
Conclusions The present study showed successful rejuvenation for age-related infertility using transplantation of meiosis-II chromosomes
in animal experimental models.
Capsule Transplantation of meiosis-II chromosomes of senescent mouse oocytes into cytoplasts of young mouse oocytes improves subsequent
embryonic and fetal development until birth. 相似文献
76.
Hideto?KamedaEmail author Koichi?Amano Naoya?Sekiguchi Hirofumi?Takei Hiroe?Ogawa Hayato?Nagasawa Tsutomu?Takeuchi 《Modern rheumatology / the Japan Rheumatism Association》2004,14(6):442-446
Methotrexate (MTX) is the most commonly used disease-modifying antirheumatic drug (DMARD) throughout the world. In Japan,
MTX is recommended by the Japanese Ministry of Health, Labour, and Welfare to be given as the second or third DMARD and at
a dosage of no more than 8 mg/week. We analyzed the efficacy of MTX in Japanese patients with RA in order to determine whether
it is comparable to that in Western countries, where 15–20 mg/week of MTX is used, as well as to elucidate the factors associated
with the favorable response to MTX. Around 8 mg/week of MTX was effective in half of the RA patients in the current study,
and male sex was the only factor associated with a good response to MTX from a multivariate regression model analysis. Some
of the patients who had a poor response to MTX showed an improvement with the addition of bucillamine or prednisolone. For
the remaining patients, an increase in the MTX dosage to more than 8 mg/week or the use of biologics such as the anti-tumor
necrosis factor (TNF)-α monoclonal antibody may be required. 相似文献
77.
Takashi Tsukahara Masaru Tamura Hiromichi Yamazaki Hideyuki Kurihara Shigeru Matsuzaki 《Journal of cancer research and clinical oncology》1992,118(3):171-175
Summary The effects of -difluoromethylornithine (DFMO), radiation and the therapy of their combination were investigated in rats bearing G-XII glioma. DFMO treatment as well as radiation therapy prolonged the survival period when compared to the results in non-treated control rats. The combination therapy showed a greater effect on the survival rate than the single therapies, the effect being additive. The concentration of putrescine, spermidine, andN
1-acetylspermidine in tumor tissues was lowered by DFMO, while that of spermine was slightly elevated. Radiation decreased the concentration of all the polyamines, putrescine, spermidine, spermine andN
1-acetylspermidine. The concomitant treatment with DFMO and radiation further decreased the concentrations of putrescine andN
1-acetylspermidine in tumor tissues. The survival period of glioma-bearing rats is inversely correlated with the tissue levels of putrescine plusN
1-acetylspermidine.Abbreviations DFMO
-difluoromethylornithine
- BrdUrd
bromodeoxyuridine 相似文献
78.
Yamazaki H Sekiguchi M Takamatsu M Tanabe Y Nakanishi S 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(40):14509-14514
Cajal-Retzius (CR) cells are early-generated transient neurons and are important in the regulation of cortical neuronal migration and cortical laminar formation. Molecular entities characterizing the CR cell identity, however, remain largely elusive. We purified mouse cortical CR cells expressing GFP to homogeneity by fluorescence-activated cell sorting and examined a genome-wide expression profile of cortical CR cells at embryonic and postnatal periods. We identified 49 genes that exceeded hybridization signals by >10-fold in CR cells compared with non-CR cells at embryonic day 13.5, postnatal day 2, or both. Among these CR cell-specific genes, 25 genes, including the CR cell marker genes such as the reelin and calretinin genes, are selectively and highly expressed in both embryonic and postnatal CR cells. These genes, which encode generic properties of CR cell specificity, are eminently characterized as modulatory composites of voltage-dependent calcium channels and sets of functionally related cellular components involved in cell migration, adhesion, and neurite extension. Five genes are highly expressed in CR cells at the early embryonic period and are rapidly down-regulated thereafter. Furthermore, some of these genes have been shown to mark two distinctly different focal regions corresponding to the CR cell origins. At the late prenatal and postnatal periods, 19 genes are selectively up-regulated in CR cells. These genes include functional molecules implicated in synaptic transmission and modulation. CR cells thus strikingly change their cellular phenotypes during cortical development and play a pivotal role in both corticogenesis and cortical circuit maturation. 相似文献
79.
Kaneki T Kawashima A Akamatsu T Tanaka N Kubo K Koizumi T Sekiguchi M Hosaka N Honda T Koike S Adachi W 《Journal of gastroenterology》1999,34(2):253-259
We report a rare case of immunoblastic lymphadenopathy (IBL)-like T-cell lymphoma complicated by multiple gastrointestinal
involvement, which appeared to be ameliorated by chemotherapy but resulted in perforative peritonitis. A 66-year-old Japanese
woman who had generalized lymphadenopathy and eruptions was admitted to our hospital because of bloody stool. Colonoscopic
examination revealed hemorrhagic ulcers in the terminal ileum and a saucer-like ulcer in the cecum. Gastrointestinal endoscopy
revealed several ulcerative or elevated lesions in stomach and duodenum. Biopsy specimens of these lesions and of a lymph
node showed characteristic histological features of IBL-like T-cell lymphoma. The initial treatment with prednisolone (PSL)
and cyclophosphamide (CPA) was effective. Six months after the treatment, however, she developed bloody stool again caused
by multiple ulcerative lesions in the large intestine. The recurrence of the disease was determined histologically, and four
courses of CPA, PSL, vinblastine sulfate and doxorubicin hydrochloride (CHOP) therapy were administered. One month after completing
the CHOP therapy, she developed intestinal obstruction and then acute peritonitis resulting from perforation at an ulcer scar
in the jejunum. Surgical treatment was successful, and histological examination demonstrated no lymphoma cells in the resected
specimen. A gastrointestinal perforation should be recognized as a potential complication of IBL-like T-cell lymphoma, even
during remission.
(Received: June 24, 1998; accepted: Oct. 23, 1998) 相似文献
80.
Different Adhesive Characteristics and VLA-4 Expression of CD34+ Progenitors in G0/G1 Versus S+G2/M Phases of the Cell Cycle 总被引:2,自引:3,他引:2