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991.
Applying hormesis in aging research and therapy 总被引:2,自引:0,他引:2
Rattan SI 《Human & experimental toxicology》2001,20(6):281-5; discussion 293-4
992.
Deep Narayan Srivastava Surinder Yadav Ashok Kumar Hemal Manorama Berry 《Journal of Medical Imaging and Radiation Oncology》1998,42(3):234-235
Chyluria is a urological manifestation of lymphatic system disease. Sclerotherapy of the renal pelvis (RPIS) using 1% silver nitrate, along with diethyl carbamazine, is the treatment most frequently used. Massive haematuria due to intrarenal aneurysm following RPIS has not been reported. A case is described here of arterial haemorrhage following instillation of silver nitrate which was treated by coil embolization. The haematuria was immediately stopped and the renal function returned to normal gradually. 相似文献
993.
Objectives:
To evaluate the ethanolic and aqueous extracts of Bauhinia variegata Linn. for in vitro antioxidant and antihyperlipidemic activity.Materials and Methods:
Ethanolic and aqueous extracts of the stem bark and root of B. variegata Linn. were prepared and assessed for in vitro antioxidant activity by various methods namely total reducing power, scavenging of various free radicals such as 1,2-diphenyl-2-picrylhydrazyl (DPPH), super oxide, nitric oxide, and hydrogen peroxide. The percentage scavenging of various free radicals were compared with standard antioxidants such as ascorbic acid and butylated hydroxyl anisole (BHA). The extracts were also evaluated for antihyperlipidemic activity in Triton WR-1339 (iso-octyl polyoxyethylene phenol)-induced hyperlipidemic albino rats by estimating serum triglyceride, very low density lipids (VLDL), cholesterol, low-density lipids (LDL), and high-density lipid (HDL) levels.Result:
Significant antioxidant activity was observed in all the methods, (P < 0.01) for reducing power and (P < 0.001) for scavenging DPPH, super oxide, nitric oxide, and hydrogen peroxide radicals. The extracts showed significant reduction (P < 0.01) in cholesterol at 6 and 24 h and (P < 0.05) at 48 h. There was significant reduction (P < 0.01) in triglyceride level at 6, 24, and 48 h. The VLDL level was also significantly (P < 0.05) reduced from 24 h and maximum reduction (P < 0.01) was seen at 48 h. There was significant increase (P < 0.01) in HDL at 6, 24, and 48 h.Conclusion:
From the results, it is evident that alcoholic and aqueous extracts of B. variegata Linn. can effectively decrease plasma cholesterol, triglyceride, LDL, and VLDL and increase plasma HDL levels. In addition, the alcoholic and aqueous extracts have shown significant antioxidant activity. By the virtue of its antioxidant activity, B. variegata Linn. may show antihyperlipidemic activity. 相似文献994.
Prognostic significance of microscopic and macroscopic extracapsular spread from metastatic tumor in the cervical lymph nodes 总被引:4,自引:0,他引:4
Ferlito A Rinaldo A Devaney KO MacLennan K Myers JN Petruzzelli GJ Shaha AR Genden EM Johnson JT de Carvalho MB Myers EN 《Oral oncology》2002,38(8):27-751
It has been established that the presence or absence of cervical node metastases in patients with head and neck squamous cell carcinoma (HNSCC) is a powerful prognostic indicator. This report reviews the evolution of thinking over the past 70 years with regard to the import and detection of cervical nodal metastases which exhibit spread of tumor beyond the confines of the original encompassing nodal capsule. In the process, this discussion touches upon clinical examination, gross and microscopic pathologic examination, and radiographic imaging studies. In particular, the distinction between gross nodal extracapsular spread of tumor and microscopic nodal extracapsular spread of tumor has been drawn in recent reports; this raises the possibility that identification of microscopic breaching of the node capsule by tumor might provide clinically significant information which is not provided by the gross observation of an intact lymph node capsule. While it remains to be seen whether microscopic extracapsular spread alone will prove to be an important prognostic factor, it is recommended that selective neck dissection continue to be offered even in those patients with clinically negative necks; further studies should aid in defining the import of microscopic extracapsular tumor spread in patients with positive cervical nodes. 相似文献
995.
Radical cystectomy remains one of the mainstay treatments for organ-confined invasive bladder cancer. Components of this surgery including the extent of pelvic lymph node dissection, the assessment of ureteric margins and the indications for bladder reconstruction as opposed to the simpler ileal conduit urinary diversion continue to provoke debate. This review provides a broad overview of radical cystectomy and summarises the options for bladder reconstruction. Special emphasis is given to data concerning the role of pelvic lymphadenectomy in the patient staged pre-operatively as N0M0. 相似文献
996.
Karegoudar P Prasad DJ Ashok M Mahalinga M Poojary B Holla BS 《European journal of medicinal chemistry》2008,43(4):808-815
The reaction of 2,3,5-trichlorobenzoic acid hydrazide with carbon disulfide and potassium hydroxide followed by treatment with hydrazine hydrate afforded 3-(2,3,5-trichlorophenyl)-4-amino-1,2,4-triazole-5-thione (6). Alternatively, this triazole was also synthesized by fusing 2,3,5-trichlorobenzoic acid with thiocarbohydrazide. Condensation of (6) with various aromatic carboxylic acids in the presence of phosphorous oxychloride or with phenacyl bromides afforded two series of fused heterocycles namely 6-(substituted aryl)-3-(2,3,5-trichlorophenyl)-[1,2,4]triazolo[3,4-b][1,3,4]thiadizoles (7) and 6-(substituted aryl)-3-(2,3,5-trichlorophenyl)-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazines (8), respectively. The structures of these newly synthesized compounds are characterised by elemental analysis, IR, (1)H NMR and mass spectroscopic studies. All the synthesized compounds were screened for their antimicrobial and anti-inflammatory activities. Some of the compounds exhibited promising antimicrobial and anti-inflammatory activities. 相似文献
997.
Theaflavins (TF) and thearubigins (TR) are the most exclusive polyphenols of black tea. Even though few previous reports showed the anticancer effects of TF through apoptosis, the potential effect of TR has not been appraised. This study investigated the induction of apoptosis in human skin cancer cells after treatment of TF and TR. We report that both TF and TR could exert inhibition of A431 (human epidermoid carcinoma) and A375 (human malignant melanoma) cell proliferation without adversely affecting normal human epidermal keratinocyte cells. Growth inhibition of A375 cells occurred through apoptosis, as evident from cell cycle arrest at G(0)/G(1) phase, increase in early apoptotic cells, externalization of phosphatidylserine and DNA fragmentation. In our pursuit to dissect the molecular mechanism of TF- and TR-induced apoptosis in A375 cells, we investigated whether cell death is being mediated by mitochondria. In our system, Bax translocation to mitochondria persuaded depolarization of mitochondrial membrane potential, cytochrome c release in cytosol and induced activation of caspase-9, caspase-3 and poly (ADP-ribose) polymerase cleavage. Our intricate investigations on apoptosis also explained that TF and TR augmented Bax:Bcl2 ratio, up-regulated the expression of p53 as well as p21 and inhibited phosphorylation of the cell survival protein Akt. Furthermore, TF and TR elicited intracellular reactive oxygen species generation in A375 cells. These observations raise speculations that TF as well as TR might exert chemopreventive effect through cell cycle arrest and induction of apoptogenic signals via mitochondrial death cascade in human skin cancer cells. 相似文献
998.
Inhibition of N-(4-hydroxyphenyl)retinamide-induced autophagy at a lower dose enhances cell death in malignant glioma cells 总被引:1,自引:0,他引:1
Tiwari M Bajpai VK Sahasrabuddhe AA Kumar A Sinha RA Behari S Godbole MM 《Carcinogenesis》2008,29(3):600-609
The question whether chemotherapy-induced autophagy is causative to the demise of the cells or a part of the survival mechanism activated during cellular distress is unclear. Others and we have previously demonstrated apoptosis-inducing capacity of N-(4-hydroxyphenyl)retinamide (4-HPR) in malignant glioma cells. We provide evidences of 4-HPR-induced autophagy at a lower concentration (5 microM). Suboptimal dose of 4-HPR treatment of malignant glioma cell lines increased G(2)/M arrest, whereas cell accumulated in S phase at a higher concentration. 4-HPR-induced autophagy was associated with acidic vacuole [acidic vesicular organelle (AVO)] formation and recruitment of microtubule-associated protein light chain 3 (LC3). At a higher concentration of 10 microM of 4-HPR, glioma cells undergoing apoptosis manifested autophagic features indicated by autophagosome formation, AVO development and LC3 localization. Autophagy inhibition at an early stage by 3-methyl adenine inhibited the AVO formation and LC3 localization with an enhancement in cell death. Bafilomycin A1, a specific inhibitor of vacuolar type Hthorn-ATPase also prevented AVO formation without effecting LC-3 localization pattern and also enhanced the extent of 4-HPR-induced cell death. 4-HPR activated c-jun and P38(MAPK) at both 5 and 10 microM concentrations, whereas increased activation of extracellular signal-regulated kinase 1/2 and NF-kappaB was seen only at lower dose. Inhibiting phosphoinositide 3-kinase and mitogen-activated protein kinases pathways modulated 4-HPR-induced cell death. This is the first report that provides evidences that besides apoptosis induction 4-HPR can also induce autophagy. These results indicate that 4-HPR-induced autophagy in glioma cell may provide survival advantage and inhibition of autophagy may enhance the cytotoxicity to 4-HPR. 相似文献
999.
This study was done to investigate whether inhalational anesthetics modulated the binding of specific ligands to opioid receptors in the brain of the rat. The effect of isoflurane and enflurane on the binding of specific ligands to various subtypes of opioid receptors in vitro was studied. Isoflurane inhibited the binding of [3H]naloxone to opioid receptors by 50% in the spinal cord, midbrain and cortex at 22, 49 and 50 mM, respectively. Enflurane was more potent than isoflurane in inhibiting the binding of [3H]naloxone. Scatchard analysis of the binding of [3H]naloxone, done in the presence of therapeutic level (5 mM) of isoflurane, suggested that it did not affect the KD (1.3 nM) but decreased the Bmax by 41% in the cortex. Isoflurane and enflurane, at large doses (30-50 mM), inhibited the binding of [3H]ethylketo-cyclazocine (EKC) to kappa receptors in midbrain, cortex and spinal cord. At a smaller dose (5 mM), they increased the binding of EKC in spinal cord. The binding of the analogs of enkephalin [3H]DSTLE(Tyr-D-Ser-Gly-Phe-Leu-Thr-enkephalin) to delta receptors and [3H]DAGO (Tyr-D-Ala-Gly-Methyl-Phe-Glyol-enkephalin) to mu receptors in the midbrain and cortex was inhibited by isoflurane at a significantly smaller concentration than the binding of [3H]naloxone, indicating that the binding of peptides was more susceptible to the inhibition by inhalational anesthetics than the binding of alkaloids, such as naloxone or EKC. These results suggest that the modulation of opioid receptors by inhalational anesthetics is a function of both the nature of the ligand and the tissue used for the receptor binding.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
1000.