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51.
Bronchioloalveolar carcinoma is a distinctive subtype of pulmonary adenocarcinoma, without effective therapy, although there have recently been some attempts to use lung transplantation. However, a high post-transplantation local recurrence rate is described with some controversy regarding the possible involved mechanisms, the main possibilities being the lymphatic spread and aerosolization. Presented herein is a case of a bilateral lung transplantation for a bilateral and pneumonic form of non-mucinous bronchioloalveolar carcinoma in a 43-year-old woman. The histological analysis of mediastinal lymph nodes during surgery did not show neoplastic cells. Thirty-five months after transplantation several nodular opacities in donor lungs were detected. Three pulmonary wedge resections were performed showing a non-mucinous bronchioloalveolar carcinoma with the same histological characteristics as the primary. Again, the mediastinal lymph nodes were tumor free. A complete microsatellites molecular analysis was performed to compare the primary and recurrent carcinoma using capillary electrophoresis, showing that the recurrent tumor was generated in a recipient cellular clone. The absence of lymph node metastasis and the molecular evidence of the recipient origin of the neoplasm supports the contamination of the new lungs at the time of implantation as being the reason for the high incidence of recurrence after lung transplantation in this kind of disease.  相似文献   
52.
Propranolol liberates histamine from isolated mast cells and decreases the uptake of extracellular histamine in a dose-dependent way. Histamine liberation due to propranolol is accompanied by calcium displacement from intracellular storage sites. The significant increase in membrane fluidity due to propranolol is temperature dependent. The perturbation of membranes is most probably the explanation of propranolol's interaction with isolated rat mast cells which results in altered histamine transportation.  相似文献   
53.
54.
Summary Human leukocyte interferon produced in primary cultures of buffy coat cells and human fibroblast interferon from cultures of the FS-4 foreskin cell strain were subjected to isoelectric focusing in polyacrylamide gels. Leukocyte interferon could be resolved into three major components (pI 5.5, 6.2 and 6.6, respectively) and one minor component (pI 7.0). Fibroblast interferon activity focused in a broad pH range of 6.8–7.8.The isoelectrically distinct subspecies of human leukocyte interferon were isolated and compared as to their antigenic nature, heterospecific antiviral activity in cultures of bovine cells, and apparent molecular weights upon electrophoresis in sodium dodecyl sulfate-polyacrylamide gels (SDS-PAGE). The three major subspecies (pI 5.5, 6.2 and 6.6) were similar in their neutralization by antiserum against whole leukocyte interferon and in their relative heterospecific activities on bovine cells. When analyzed on SDS-PAGE, the component focusing at pH 5.5 migrated to a position corresponding to a molecular weight of 17,500 (Le f), the component with the pI of 6.6 had its major peak corresponding to a molecular weight of 23,000 (Le s), while the pI 6.2 component contained a mixture of the two molecular weight species. The minor isoelectric component focusing at pI 7.0 contained interferon with the antigenic specificity of fibroblast (F) interferon. It is concluded that the two major antigenic species of human interferon (Le andF) and two known subspecies of human leukocyte interferon (Le s andLe f) can be resolved by isoelectric focusing.With 3 Figures  相似文献   
55.
Summary Translation of poliovirus RNA is initiated by entry of ribosomes into the nucleotide sequence (internal ribosomal entry site; IRES) within the 5-untranslated region (5-UTR). Efficiency of this translation initiation in rabbit reticulocyte lysates (RRL) was very low and was greatly enhanced by addition of the ribosomal salt-wash fraction (RSW) prepared from HeLa cells. This stimulating activity in the RSW was partially purified by gel-filtration column chromatography and its molecular weight was estimated to be higher than 240 000. Several proteins that bind specifically to the poliovirus IRES were detected in the active fraction. Among those, a 57 kDa protein, recognized by antibodies against polypyrimidide tract-binding protein (PTB), was found. In addition, La protein (52 kDa) which is a human antigen recognized by antibodies from patients with autoimmune disorders was also detected. Further purification on a hydroxylapatite column resulted in considerable loss of the stimulatory activity, accompanied by a reduction of the apparent molecular weight of active component(s). These results suggest that fully active HeLa cell stimulatory factors for the translation initiation on poliovirus RNA function in RRL as a large complex consisted of several components including PTB and La protein.  相似文献   
56.
The past decade has been marked by significant advances in the application of gene transfer into living cells of animals and humans, with the resulting catapulting of preclinical and basic scientific concepts into therapeutic trials. A variety of virus-mediated gene delivery techniques have proved to be superior to other methodologies. This article concisely reviews the current status of gene and tumor therapy, focusing on virus-based technologies, describes the molecular biology of neurotropic herpesviruses and the application of herpes simplex virus, a relative of pseudorabies virus (PRV) in gene transfer and cancer therapy protocols. Finally, it addresses the issue of whether PRV, a nonhuman pathogen, could serve as a suitable research and therapeutic tool as concerns genetic and tumor therapy.  相似文献   
57.
New types of hydrophilic gels based on N-(2-hydroxypropyl)methacrylamide which contain oligopeptide sequences in the crosslinks were prepared. These gels are enzymatically degradable by chymotrypsin. The rate of their degradation may be varied within a broad range by changes in the length and detailestructure of the oligopeptide sequence in the crosslinks and by changing their network density.  相似文献   
58.
Antibody content against rabbit red blood cells (anti-RaRBC) in murine sera of different strains (Swiss, CBA, C57BL/6, AKR, BALB/c) and activity of complement alternative pathway (AP) were investigated. In contrast to the CBA and C57BL/6, random-bred Swiss strain and inbred BALB/c and AKR strains are good producers of these natural antibodies. There is no correlation between AP activity and anti-RaRBC content. Isolated human anti-RaRBC antibodies, IgM and IgG classes, lead to the enhancement of APhu and APmo activity, contrary to the murine anti-RaRBC which belong solely to IgM class, and do not express this capability.  相似文献   
59.
Charcot-Marie-Tooth disease, type 1A (CMT1A) is caused in most cases by a 1.5 Mb duplication on chromosome 17p11.2 arising after unequal crossing-over between repeated sequences called CMT1A-REPs, flanking the 1.5 Mb unit. A 3.2 kb recombination hot spot has been defined, resulting in a junction fragment between EcoRI (distal CMT1A-REP) and SacI (proximal CMT1A-REP). This was further reduced to a 1.7kb EcoRI-NsiI fragment, and recently to a 731 bp hot spot region within this fragment. We describe the CMT1A-REPs-based PCR method used to identify CMT1A duplications and report on a family case in which a 29-year-old pregnant woman requested prenatal diagnosis for two successive pregnancies because her husband was affected with CMT1A. Our method enabled us to characterise the duplication in both foetuses and demonstrate that it arose from a rare recombination event taking place outside the 1.7 kb region. Since our approach is simple and enables the entire set of duplications occurring after recombination in the enlarged 3.2kb region including the hot spot to be detected, we suggest it might be considered for use in primary screening for pre- and postnatal diagnosis of CMT1A.  相似文献   
60.
Several problems in the management of life-threatening mucormycosis remain unresolved, necessitating new methods of management. Four patients with histopathologically proven rhinocerebral mucormycosis were treated with high cumulative doses of granulocyte colony-stimulating factor (G-CSF). All had multiple predisposing factors for mucormycosis, particularly leukemia and neutropenia. Two patients refractory to fluconazole therapy were treated with liposomal amphotericin B. The improvement in clinical manifestations was closely related to neutrophil recovery, and all patients were alive at the end of therapy. In addition to surgical debridement and antifungal therapy, G-CSF seems to have played a role in their survival.  相似文献   
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