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61.
H M Eun  Y S Bae  J W Yoon 《Virology》1988,163(2):369-373
The genes for the major capsid protein, VP1(1D), of both diabetogenic D variant (EMC-D) and nondiabetogenic B variant (EMC-B) of encephalomyocarditis virus were cloned by using two synthetic primers which are common to both EMC-D and EMC-B. The cloned genes were mapped for major restriction enzyme sites including AccI, BamHI, EcoRI, HincII, KpnI, PvuII, SstI, TaqI, and XbaI. Among those nine restriction enzyme sites, only the TaqI site distinguished EMC-D genome from the counterpart of EMC-B genome. The complete nucleotide sequences (831 bases) of the VP1 genes revealed five amino acid differences between the two variants. Three of the changes, at positions 41, 58, and 152, were Thr (EMC-B) to Ala (EMC-D). The additional two changes occurred at positions 63 [Gln (EMC-B) to Glu (EMC-D)] and 181 [Thr (EMC-B) to Ser (EMC-D)]. All of these amino acid changes were due to point mutations at the first base of each codon.  相似文献   
62.
目的 研究rALR对HBsAg及BSA免疫大鼠产生抗体、细胞因子和对脾脏细胞增殖的影响.方法 甲醇诱导表达rALR,测定活性并进行以下研究.①rALR对HBsAg免疫的影响:实验分为:生理盐水、HBsAg20 μg/只、HBsAg20 μg rALR100 μg/kg、HBsAg20 μg rALR 25 μg*kg、HBsAg20 v pPIC9K表达上清、HBsAg20 μg CsA10mg/kg,共6组;②rALR对BSA免疫的影响:实验分为:生理盐水、BSA25 μg/只、BSA25 μg rALR100 μg/kg、BSA25 μg pPIC9K表达上清、BSA25 μg CsA10 mg/kg,共5组.以上均皮下注射免疫大鼠,1次/周×4次,ELISA检测血清中相应抗体、IL-2和IFN-γ.③rALR对大鼠脾细胞增殖的影响:Wisar大鼠先皮下注射HBsAg(20 μg/只)1次,2周后处死,分离脾单核细胞,种板,再加HBsAg 1 μg/孔和/或相应处理因素(rALR、空质粒表达产物等),48h后加3H-TdR,12 h后收集细胞,检测cpm值.结果 rALR100 μg/kg HBsAg组的8只动物中,有2只出现抗HBs的抗体,空质粒对照组和单用HBs Ag组8只动物均出现抗HBs.rALR 100 μg/kg BSA组的8只动物中,有3只出现抗BSA抗体,空质粒对照组和单用BSA组8只动物均出现抗BSA的抗体.rALR 100μg/kg能明显抑制细胞因子IL2及IFN-γ的产生.rALR4μg体外能明显抑制脾细胞的增殖.结论 rALR能抑制HBsAg和BSA诱导大鼠产生相应抗体及IL-2、IFN-γ的产生;体外能抑制经体内致敏的脾细胞的增殖,说明rALR有免疫抑制作用.  相似文献   
63.
Recent clinical trials showed that bortezomib, a novel proteasome inhibitor, had therapeutic activity in multiple myeloma. However, there was no data about the feasibility of bortezomib in Korean patients. We performed a pilot study of bortezomib in patients with relapsed or refractory myeloma (1.3 mg/m2 twice weekly for 2 week in a 3-week cycle). Seven patients were enrolled. The median age of patients was 59 yr. All patients previously received VAD (vincristine, doxorubicin and dexamethasone) and thalidomide chemotherapy. Three patients previously received alkylator-containing chemotherapy and 4 patients, autologous stem cell transplantation. Bortezomib monotherapy resulted in 3 partial remissions (43%), 3 no changes (43%) and 1 progressive disease (14%). One patient who had no response to bortezomib monotherapy experienced partial remission after addition of dexamethasone to bortezomib. The most common serious toxicity was thrombocytopenia (grade 3/4, 10 of 20 cycles (50%)) and grade 3 peripheral neuropathy was developed in 2 of 20 cycles (10%). Drug-related adverse event led to discontinuation of bortezomib in 1 patient. There was no treatment related mortality. Overall, bortezomib seems to be effective and feasible. Conduction of larger clinical studies on Korean patients is necessary to characterize clinical efficacy and safety of bortezomib more precisely.  相似文献   
64.
While diffuse mesangial sclerosis is traditionally described as being the glomerulopathy of Denys–Drash syndrome (DDS), the podocyte proliferative lesions may be overlooked in these DDS cases. In the present study, an evolving process is extrapolated from a selected case of DDS that demonstrated glomerulopathy with conspicuous podocyte proliferation. The observation that podocytes express proliferation markers (Ki67, proliferating-cell nuclear antigen and topoisomerase II) in non-proliferative, mature-looking glomeruli suggests an initial pathogenic act to activate or to keep podocytes from quiescence. The subsequent proliferation of podocytes is in keeping with downregulation of WT1 and cyclin kinase inhibitors of p16 and p21. The emergence of cytokeratin-positive cells in glomeruli that show typical mesangial sclerosis implies elimination of podocytes and replacement with tubular and/or parietal epithelial cells. The final scene of evolving glomerulopathy displays apoptosis and expression of Fas-L and Bax in sclerotic mesangial lesions, which eventually end up with global sclerosis. This novel concept of DDS glomerulopathy implies complex molecular mechanisms involved in glomerular injury.  相似文献   
65.
FVB and BALB/c mice show different morbidity, development of Clonorchis sinensis, and pathological changes following C. sinensis infection. FVB mice are susceptible and BALB/c mice are relatively more resistant to C. sinensis infection. To investigate the relationship between cytokine reaction and susceptibility to C. sinensis infection in FVB and BALB/c mice, we described both the patterns and kinetics of Th1 cytokines and Th2 cytokines in spleen cell culture. Interleukin (IL)-4 and IL-10 cytokine production in the culture supernatants of the concanavalin-A-stimulated spleen cells increased at 2–3 weeks post-infection in both strains. IL-5 production increased between 2 and 5 weeks post-infection in both strains, and reached a peak level at 2 weeks post-infection in BALB/c mice and 4 weeks post-infection in FVB mice. In contrast, gamma interferon (IFN-) production decreased between 2 and 4 weeks in both strains. IL-2 production increased slightly in BALB/c mice following infection, but was unchanged in FVB mice. IL-4 production over preinfection levels was significantly higher in FVB mice, whereas IFN-, IL-2, and IL-10 production were significantly higher in BALB/c mice. The levels of serum immunoglobulin E (IgE) and blood eosinophils in both mouse strains significantly increased between 3 and 6 weeks postinfection. Serum IgE levels were significantly higher in FVB mice than in BALB/c mice. The results of this study suggest that susceptibility to C. sinensis infection is associated with Th2 cytokine production, especially IL-4 which is predominant in relatively susceptible FVB mice.  相似文献   
66.
In order to determine the effect of ultraviolet radiation (UVR) on the cell adhesion molecules expressed in human dermal microvascular endothelial cells (HDMEC), the cells were exposed to varying UVR doses and the cell surface was examined for expression of intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM- 1), and E-selectin. The effect of UVB irradiation on the binding of T lymphocytes to HDMEC was also examined. UVA irradiation did not affect the surface expression of ICAM-1, VCAM-1, or E-selectin on the HDMEC. However, following UVB exposure, ELISA demonstrated a significant increase in the baseline ICAM-1 cell surface expression on the HDMEC. However, no induction of either E-selectin or VCAM-1 was noted. UVB also significantly augmented ICAM-1 induction by IL-1alpha and TNF-alpha. VCAM-1 was induced by stimulating HDMEC with IL-1alpha following a UVB irradiation dose of 100 mJ/cm2. Flow cytometric analysis of the HDMEC stimulated with IL-1alpha for 24h demonstrated that 12% of the cells expressed VCAM-1 but either IL-1alpha or UVB irradiation alone failed to induce VCAM-1 expression. Enhancement of T cell-HDMEC binding by IL-1alpha or TNF-alpha treatment was not significantly affected after UVB irradiation. This study demonstrated that UVB irradiation can alter ICAM-1 and VCAM-1 expression on the HDMEC surface and that augmentation of ICAM-1 expression and the IL-1alpha-dependent induction of VCAM-1 following UVB exposure might be important steps in the pathogenesis of sunburn.  相似文献   
67.
Ring-opening polymerization of a new anhydro ribose-type monomer, 1,4-anhydro-3-azido-3-deoxy-2-O-tert-butyldimethylsilyl-α-D -ribopyranose (A3ASR), was investigated. The monomer was synthesized from 1,4-anhyro-α-D -xylopyranose by three steps comprising Walden inversion at the C3 position into ribose configuration. Ring-opening polymerization of A3ASR by Lewis acid catalysts such as boron trifluoride etherate and stannic chloride gave a stereoregular 3-azido-3-deoxy-2-O-tert-butyldimethylsilyl-(1→5)-α-D -ribofuranan having specific rotations of +246 ~ +271 deg · dm?1 · g?1 · cm3 and number-average molecular weights of 18,7 × 103 ~ 25,1 × 103. When the polymerization was carried out by antimony pentachloride at 0°C, the resulting polymer exhibited a negative specific rotation of ?6 deg · dm?1 · g?1 · cm3 and the C1 absorption in the 13C NMR spectrum shifted downfield to 107,5 ppm, suggesting that the polymer might consist of 1,5-β furanosidic unit. The reduction of the azido group of the 1,5-α and 1,5-β furanosidic polymers into amino group and subsequent desilylation gave 3-amino-3-deoxy-(1→5)-α- and -β-D -ribofuranans, respectively. In addition, copolymerization of A3ASR with 1,4-anhydro-2,3-di-O-tert-butyldimethylsilyl-α-D -ribopyranose (ADSR) in various feeds was performed by boron trifluoride etherate as catalyst to give copolymers with different monomeric components. The structural analysis of the homopolymers and copolymers was examined by means of 1H and 13C NMR spectroscopies, IR spectroscopy, and optical rotation.  相似文献   
68.
Malignant transformation of mature cystic teratoma of the ovary can develop with an incidence of 1-2%. Squamous cell carcinoma is the most common malignant tumor arising in benign cystic teratoma. The authors have recently experienced a case of combined microcystic adnexal carcinoma and squamous cell carcinoma arising in a benign cystic teratoma of the ovary in a 72-year-old Korean woman. The right ovarian cystic mass had been ruptured and firmly adhered with salpinx and omental fat tissue on operation. Thickened cystic wall with yellowish white solid infiltrative lesion was noted grossly, and two different malignant tumors of microcystic adnexal carcinoma exhibiting both eccrine and hair follicular differentiation and squamous cell carcinoma were observed microscopically. PAS and CEA positivities suggested eccrine differentiation in areas of microcystic adnexal carcinoma.  相似文献   
69.
The diabetogenic capacity of the M-variant of encephalomyocarditis (EMC) virus was markedly diminished after passage in mouse kidney cell cultures. One passage in mice fully restored this capacity. Virus harvested after five passages in either susceptible (SWR/J) or resistant (C57BL/6J) strains of mice was capable of producing diabetes in susceptible SWR/J mice but not in resistant C57BL/6J mice. Resistance was not overcome by inoculating mice with high concentrations of virus. Immunofluorescence studies showed that islets from strains of mice (i.e. CBA, AKR, C57BL/6J, A/J) that did not develop diabetes after infection with EMC virus, nonetheless, contained virus antigens. The percentage of cells in the islets containing virus antigens varied from 3-6% in CBA to 13-5% in A/J. In contrast 38% of the islet cells in susceptible SWR/J mice contained virus antigens. It is concluded that both the genetic background of the host and the passage history of the virus influence the development of diabetes.  相似文献   
70.
There is a need to develop human hepatocyte cell lines which retain both replicating capacity and highly differentiated functions to facilitate the development of an efficient bioartificial liver. The present study was undertaken to differentiate, using sodium butyrate, the actively replicating immortalized human liver cell line. The effects of butyrate on cell growth and cell cycle were analyzed, and the albumin synthesis, cytochrome P450 and ammonia-detoxifying activity of the butyrate-treated cells were measured. Butyrate treatment resulted in G2/M arrest of the cell cycle and polygonal changes in the cell morphology. Neither the control nor the butyrate-treated cells showed transformed characteristics. Butyrate treatment increased the amount of albumin secretion, cytochrome P450 activity, and the urea production rate of the cells. The present study provides non-transformed human hepatocytes, which can replicate unlimitedly and then restore differentiated hepatocyte-specific functions by butyrate, and therefore, have applications for the development of an efficient bioartificial liver.  相似文献   
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