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11.
12.
A terminal transferase-mediated dUTP nick end labeling (TUNEL) method was utilized for detection of neuronal death in the subcortical relay nuclei of the trigeminosensory system following the infraorbital nerve transection in newborn rats. At 18-24 h after injury, numerous TUNEL-positive profiles were found within the ventroposteromedial thalamic nucleus (VPM) contralateral to the injury, whereas the VPM on the ipsilateral side and of the age-matched normal control contained only a few profiles per section. Electron microscopy revealed that the TUNEL-positive profiles were apoptotic neurons. The ventral part of the ipsilateral brainstem sensory trigeminal nuclear complex (the nucleus principalis, and the subnuclei oralis and interpolaris) exhibited statistically significant 65-70% increase in number of apoptotic neurons compared to the contralateral side. Taken together with our previous study [T. Sugimoto, C. Xiao, H. Ichikawa, Neonatal primary neuronal death induced by capsaicin and axotomy involves an apoptotic mechanism, Brain Res. 807 (1998) 147-154], the present results demonstrated a cascade of apoptosis in the primary, secondary and tertiary order sensory neurons along the neuroaxis.  相似文献   
13.
We examined the effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) and cefmetazole sodium on survival, neutrophil count, and neutrophil function in rats with peritonitis produced by cecal ligation and puncture. Rats with peritonitis received either rhG-CSF (50 or 100 g/kg) with or without cefmetazole (50 mg/kg) for 3 days, cefmetazole alone, or no treatment and were evaluated as controls. The mortality rate of all treated rats was significantly lower than that of the untreated rats. The survival rate was 57.1% for the rats given both rhG-CSF and cefmetazole, but there was no significant improvement of survival as compared with cefmetazole therapy alone. Treatment with rhG-CSF at 100 |Gmg/kg caused the circulating neutrophil count to increase significantly. The phagocytic activity for latex beads and neutrophil H2O2 production showed a greater enhancement by phorbol myristate acetate (PMA) in the untreated rats, thus indicating that neutrophils from treated rats were more activated. These findings show that rhG-CSF can improve survival and neutrophil function in rats with peritonitis, while combined therapy with cefmetazole was also found to be beneficial.  相似文献   
14.
Hori Y  Takeyama Y  Ueda T  Shinkai M  Takase K  Kuroda Y 《Surgery》2000,127(6):641-649
BACKGROUND: The mechanism of acute pancreatitis-induced hepatocellular injury is unclear. We have observed hepatocyte apoptosis in rat acute necrotizing pancreatitis. These studies were designed to determine the mediator(s) responsible for hepatocyte apoptosis and to clarify the significance of macrophages as its source. METHODS: A rat sodium deoxycholate-induced pancreatitis model was used. Immunohistochemical studies for apoptosis-inducing mediators on hepatocytes were examined in the liver and on the peritoneal macrophages. The levels of transforming growth factor-beta1 (TGF-beta1) were also evaluated quantitatively with an enzyme-linked immunosorbent assay. Induction of apoptosis on the hepatocytes was evaluated by in situ nick-end labeling and tissue DNA fragmentation enzyme-linked immunosorbent assay. Finally, the effects of TGF-beta1 neutralization and macrophage depletion were examined. RESULTS: In the liver and the peritoneal macrophages, strong expression of TGF-beta1 was detected early in the course of pancreatitis. In sodium deoxycholate-induced pancreatitis, the levels of TGF-beta1 were also elevated in the plasma (9.2 +/- 0.8 ng/mL), in the pancreatitis-associated ascitic fluid (11.5 +/- 0.6 ng/mL), and in the liver homogenate (2.8 +/- 0.3 ng/g of liver tissue). Moreover, the amount of fragmented DNA of the liver with pancreatitis was 290% +/- 20% of that with a sham operation and serum alanine aminotransferase levels elevated to 248.2 +/- 67.0 IU/L. TGF-beta1 neutralization partly blocked the positive labeling on the nuclei of the hepatocytes, the elevation of the amounts of fragmented DNA (205% +/- 10% of sham operation), and the serum alanine aminotransferase level (144.2 +/- 14.9 IU/L). On the other hand, the macrophage depletion caused a marked decrease in the TGF-beta1 protein level in the plasma (4.8 +/- 1.2 ng/mL) or in the pancreatitis-associated ascitic fluid (8.0 +/- 1.0 ng/mL). Moreover, the macrophage depletion completely inhibited the elevation of the TGF-beta1 protein level in the liver homogenate (1.5 +/- 0.4 ng/g of liver tissue), and thereafter decreased the amounts of the positive labeling on the nuclei of the hepatocytes and decreased the amount of fragmented DNA (120% +/- 18% of sham operation) and the serum alanine aminotransferase elevation (119.2 +/- 24.2 IU/L). CONCLUSIONS: In a model of sodium deoxycholate-induced pancreatitis, macrophages are responsible for pancreatitis-induced hepatocellular injury by means of apoptosis, and macrophage-derived TGF-beta1 is one of the major factors inducing the hepatocyte apoptosis.  相似文献   
15.
The gut microbiota is closely related to good health; thus, there have been extensive efforts dedicated to improving health by controlling the gut microbial environment. Probiotics and prebiotics are being developed to support a healthier intestinal environment. However, much work remains to be performed to provide effective solutions to overcome individual differences in the gut microbial community. This study examined the importance of nutrients, other than dietary fiber, on the survival of gut bacteria in high-health-conscious populations. We found that vitamin B1, which is an essential nutrient for humans, had a significant effect on the survival and competition of bacteria in the symbiotic gut microbiota. In particular, sufficient dietary vitamin B1 intake affects the relative abundance of Ruminococcaceae, and these bacteria have proven to require dietary vitamin B1 because they lack the de novo vitamin B1 synthetic pathway. Moreover, we demonstrated that vitamin B1 is involved in the production of butyrate, along with the amount of acetate in the intestinal environment. We established the causality of possible associations and obtained mechanical insight, through in vivo murine experiments and in silico pathway analyses. These findings serve as a reference to support the development of methods to establish optimal intestinal environment conditions for healthy lifestyles.  相似文献   
16.
Tranexamic acid (TXA) reduces the risk of bleeding trauma death without altering the need for blood transfusion. We examined the effects of TXA on coagulation and fibrinolysis dynamics and the volume of transfusion during the early stage of trauma. This subanalysis of a prospective multicenter study of severe trauma included 276 patients divided into propensity score–matched groups with and without TXA administration. The effects of TXA on coagulation and fibrinolysis markers immediately at (time point 0) and 3 hours after (time point 3) arrival at the emergency department were investigated. The transfusion volume was determined at 24 hours after admission. TXA was administered to the patients within 3 hours (median, 64 minutes) after injury. Significant reductions in fibrin/fibrinogen degradation products and D-dimer levels from time points 0 to 3 in the TXA group compared with the non-TXA group were confirmed, with no marked differences noted in the 24-hour transfusion volumes between the 2 groups. Continuously increased levels of soluble fibrin, a marker of thrombin generation, from time points 0 to 3 and high levels of plasminogen activator inhibitor-1, a marker of inhibition of fibrinolysis, at time point 3 were observed in both groups. TXA inhibited fibrin(ogen)olysis during the early stage of severe trauma, although this was not associated with a reduction in the transfusion volume. Other confounders affecting the dynamics of fibrinolysis and transfusion requirement need to be clarified.  相似文献   
17.
BACKGROUND: Peripheral blood stem cell (PBSC) reinfusion has been widely used for hematopoietic reconstitution after high-dose chemotherapy. However, the optimal dose of granulocyte colony-stimulating factor (G-CSF) for PBSC mobilization in combination with chemotherapy for autograft remains unknown. METHODS: To find the optimal dose of glycosylated G-CSF (lenograstim) for PBSC mobilization in combination with chemotherapy for aggressive non-Hodgkin's lymphoma (NHL), we conducted a dose-finding study on 43 newly diagnosed patients who had unfavorable prognostic factors. They received four to six courses of cyclophosphamide, doxorubicin, vincristine and prednisolone combined with lenograstim every 2 weeks (biweekly CHOP therapy). PBSC apheresis was started after the third course of biweekly CHOP therapy. Lenograstim was given daily from day 3 until the day of the last apheresis. The optimum dose of lenograstim was assessed based on mobilization efficacy and safety profiles at a daily single dose of 2, 5 and 10 microg/kg for eight patients in each level. RESULTS: The collected number of CD34+ cells in the first apheresis products was higher in the 5 microg/kg group than in the 2 microg/kg group (median, 4.22 x 10(6) vs 2.49 x 10(6) CD34+ cells/kg, P = 0.051). The highest dose of 10 microg/kg (median, 2.99 x 10(6) CD34+ cells/kg) failed to show a dose dependence in PBSC mobilization. The efficacy and safety of the 5 microg/kg dose were further confirmed in an additional 19 patients. CONCLUSIONS: The present study suggests that the recommended dose of lenograstim for PBSC mobilization with CHOP therapy in untreated NHL is 5 microg/kg.  相似文献   
18.
What is known and Objective:  Pilocarpine, a muscarinic receptor agonist, has been used for the treatment of dry mouth. Salivary glands are supplied with nerve fibres that contain neuropeptides, such as substance P, calcitonin gene‐related peptide (CGRP) and vasoactive intestinal polypeptide (VIP), which are important modulators of salivation. It is known that measurement of salivary and plasma levels of neuropeptides is useful for assessing the dose–pharmacological effect relationship of drugs. The relationship between the action of pilocarpine and neuropeptides in humans has not been studied. Moreover, studies evaluate the usefulness of drug salivary levels in the pharmacological evaluation of drugs are scarce. The aim of this study was to examine the effects of pilocarpine on the levels of substance P‐, CGRP‐ and VIP‐like immunoreactive substances (IS) in saliva and plasma taken in healthy humans. Methods:  Five healthy male subjects participated in this study. Pilocarpine tablet (10 mg) or placebo tablet was orally administered with 100 mL of water. Each subject was administered placebo and drug with an interval of 4 weeks in between. Saliva was sampled before and at 20, 40, 60, 90, 120, 180 and 240 min after administration of the test substances. Venous blood samples (10 mL) were also taken from a forearm vein at each time interval. The samples were then enzyme immunoassayed using a highly sensitive system for substance P‐, CGRP‐ and VIP‐IS. The amount of saliva was measured by the Saxon test. Results:  A single oral administration of pilocarpine increased the release of salivary substance P‐IS (the area under the concentration‐time curve: AUC0→240 min) compared with the placebo. Pilocarpine also significantly increased the release of salivary CGRP‐IS (AUC0→240 min). Pilocarpine significantly increased the release of plasma CGRP‐IS. The salivary volume correlated with the salivary level of substance P and CGRP‐IS (r = 0·84, P < 0·05 and r = 0·59, P < 0·05, respectively). AUC0→240 min for substance P‐IS in saliva correlated with that for plasma (r = 0·78, P < 0·05). What is new and Conclusion:  Pilocarpine increases the release of salivary substance P and CGRP‐IS. This suggests that one mechanism by which pilocarpine improves dry mouth is by local stimulation of neuropeptidergic nerves. Moreover, saliva levels of substance P showed good correlation with the plasma levels. The substance P levels in saliva and plasma may be good indicators of the effects of drugs used in dry mouth/xerostomic patients.  相似文献   
19.
Enzyme enhancement therapy (EET) for Fabry disease involving imino sugars has been developed and attracted interest. It is thought that imino sugars act as pharmacological chaperones for wild-type and mutant α-galactosidases (GLAs) in cells, but the mechanisms underlying the molecular interactions between the imino sugars and the enzyme have not been clarified yet. We examined various kinds of imino sugars and found that galactostatin bisulfite (GBS) inhibited GLA in vitro and increased the enzyme activity in cultured Fabry fibroblasts as in the case of 1-deoxygalactonojirimycin (DGJ). Then, we analyzed the molecular interactions between the imino sugars and recombinant human GLA by means of isothermal titration calorimetry and surface plasmon resonance biosensor assays, and first determined the thermodynamic and binding-kinetics parameters of imino sugar and GLA complex formation. The results revealed that DGJ bound to the enzyme more strongly than GBS, the binding of DGJ to the enzyme protein being enthalpy-driven. In the case of GBS, the reaction was mainly enthalpy-driven, but there was a possibility that entropy-driven factors were involved in the binding. Structural analysis in silico revealed that both the chemicals fit into the active-site pocket and undergo hydrogen bonding with residues comprising the active-site pocket including the catalytic ones. The side chain of GBS was oriented towards the entrance of the active-site pocket, and thus it could be in contact with residues comprising the wall of the active-site pocket. Thermodynamic, kinetic and structural studies should provide us with a lot of information for improving EET for Fabry disease.  相似文献   
20.
This study was undertaken to determine the effect of synthetic chicken vasoactive intestinal peptide (VIP) on pancreatic blood flow, exocrine and endocrine secretions of the pancreas, and biliary secretion in dogs. The effect of synthetic chicken VIP on pancreatic blood flow and systemic arterial pressure was identical to that of natural chicken VIP in dogs. The present study demonstrated that synthetic chicken VIP induces significant increases in pancreatic blood flow, pancreaticobiliary secretion, and blood levels of insulin and glucose in dogs. Both the volume of pancreatic juice and blood levels of insulin were increased in consonance with the increase of pancreatic blood flow. This study suggests that the stimulatory effects of synthetic chicken VIP on exocrine and endocrine secretions of the pancreas may be related to the increased pancreatic blood flow elicited by synthetic chicken VIP.  相似文献   
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