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71.
The cortisone-resistant lymphocytes (CR lymphocytes) of mice treated with a group A streptococcus, Su strain, or Freund's complete adjuvant (FCA) were examined for their cytotoxicity on Ehrlich carcinoma cells and sarcoma-180 cells. Female mice of the ddY strain, 7-8 weeks of age, were injected subcutaneously with streptococci or FCA in emulsion, and they were killed 14 days later. To obtain CR lymphocytes, mice treated with and without agents were injected intraperitoneally with hydrocortisone acetate (125 mg/kg) 2 days before killing. Tumor cells and CR lymphocytes from thymus, spleen or mesenteric lymph node were suspended in Hanks balanced salt solution supplemented with 2% bovine albumin. The cytotoxicity of CR lymphocytes on tumor cells was examined by the Winn test: Tumor growth was observed in mice inoculated s.c. with the mixture of tumor cells (T) and CR lymphocytes (L) at a T/L ratio of 1/10 (10(6) tumor cells/mouse). The mesenteric and thymic CR lymphocytes of mice treated with streptococci or FCA were more effective than the corresponding lymphocytes of untreated mice in suppressing the tumor growth in animals given the cell mixture. This suggests that the treatment of mice with streptococci or FCA results in an enhancement in the cytotoxicity of mesenteric and thymic CR lymphocytes against the tumor cells.  相似文献   
72.
A 3-month-old boy with Pena-Shokeir syndrome underwent tracheotomy under general anesthesia. Patients with this syndrome may present anesthetic problems involving difficulties in tracheal intubation, possibilities of malignant hyperthermia, as well as perioperative respiratory complications related to hypoplasia of the lung. General anesthesia was induced and maintained with sevoflurane (2-3%) and nitrous oxide (0-50%) in oxygen (50-100%). The patient developed bronchospasm during tracheotomy. Atropine and epinephrine were administered intravenously and 5% sevoflurane was inhaled. The bronchospasm was improved gradually and surgery was successfully finished. Pena-Shokeir syndrome is an uncommon disease first reported by Pena & Shokeir in 1974 and characterized by congenital multiple arthrogryposis, characteristic facies, camptodactyly and pulmonary hypoplasia. In the perioperative management for a patient with Pena-Shokeir syndrome, special attention should be paid to abnormalities in the upper and lower respiratory systems, especially bronchospasm.  相似文献   
73.
Rhabdomyolysis results from a variety of causes. We experienced 6 cases of rhabdomyolysis induced by dehydration in psychoneurosis patients or seniors. We should know dehydration as a risk factor for rhabdomyolysis especially in psychoneurosis patients or seniors.  相似文献   
74.
BACKGROUND: The mechanism involved in the spontaneous acceptance of liver allografts in some rat strain combinations remains unclear. Immunoregulatory NKR-P1TCRalphabetaT (NKT) cells primarily produce IL-4 and IFN-gamma, and enhance the polarization of immune responses to Th2 and Th1, respectively. The aim of this study was to clarify the role of graft-derived NKT cells in inducing the spontaneous acceptance of rat orthotopic liver transplantation (OLTx) METHODS: The experimental groups were divided as follows: Group 1, BN to LEW "low responder (acceptor)" combination; Group 2, DA to LEW "high responder (rejector)" combination; na?ve BN (Group 3) or LEW recipients (Group 4) with liver allografts from irradiated BN donors. The recipients had liver allografts from irradiated donors reconstituted from the following cell populations 24 hr before harvesting, spleen cells (SPCs, Group 5), IgSPCs (Group 6), IgNKR-P1SPCs (Group 7), and IgTCRabSPCs (Group 8) RESULTS: In Group 1, the percent of graft-derived NKT cells harvested on day 7 posttransplant were significantly higher than in Group 2. In the case of BN liver allografts that had been irradiated and reconstituted with cell populations including NKT cells (Groups 5 and 6), the mean graft survival (MST) was extended to 39.2+/-5.7 and 38.8+/-8.0 days, respectively. In contrast, when NKT cells were excluded (Groups 7 and 8), the grafts were acutely rejected within MST of 17.8+/-4.0 and 18.8+/-7.7 days, respectively. The concentrations of IL-10 and TGF-beta, but not IL-4 in IgGICs culture supernatants were predominant in the acceptor, whereas those with IFN-gamma predominated in the rejector. CONCLUSIONS: Graft-derived NKT cells might be responsible for spontaneous acceptance in the rat OLTx.  相似文献   
75.
A nephritogenic antigen for acute poststreptococcal glomerulonephritis (APSGN) was isolated recently from group A streptococcus and termed nephritis-associated plasmin receptor (NAPlr). In vitro experimental data indicate that the pathogenic role of NAPlr occurs through its ability to bind to plasmin and maintain its proteolytic activity. However, the mechanism whereby this antigen induces glomerular damage in vivo has not been fully elucidated. Renal biopsy tissues from 17 patients with APSGN, 8 patients with rapidly progressive glomerulonephritis, and 10 normal kidneys were analyzed in this study. Plasmin-like activity was assessed on cryostat sections by in situ zymography with a plasmin-sensitive synthetic substrate. Serial sections were simultaneously assessed for NAPlr deposition by immunofluorescence staining. Glomerular plasmin-like activity was absent or weak in normal controls and in patients with rapidly progressive glomerulonephritis, although tubulointerstitial activity was occasionally detected. Prominent glomerular plasmin-like activity was found in patients who had APSGN and in whom glomerular NAPlr was positive, whereas it was absent or weak in patients who had APSGN and in whom glomerular NAPlr was negative. The distribution of glomerular plasmin-like activity was identical to that of NAPlr deposition but was generally different from that of fibrin(ogen) deposition as assessed by double staining. The activity was abolished by the addition of aprotinin to the reaction mixture but was not altered by the addition of a matrix metalloprotease inhibitor, a cysteine protease inhibitor, or inhibitors of plasminogen activators. Thus, upregulated glomerular plasmin-like activity in relation to NAPlr deposition in APSGN was identified. This result supports the nephritogenic character of NAPlr and offers insight into the mechanism whereby this antigen induces nephritis.  相似文献   
76.
Human malignant cells, obtained from surgical specimens or pleuro-peritoneal exudate in 105 cases, were cultivated. Tumor-specific immunity was estimated by cytotoxicity assay using mixed autologous lymphocyte-tumor cell culture in 27 cases (40 times in all). Relations of the observed specific immunity to various nonspecific immunological parameters and to clinical responses to immunotherapy were examined. Positive reaction was observed in 14 examinations. Eight of 25 digestive tract cancers and 6 of 15 other cancers were positive. Cytotoxic activity was significantly higher in the group of favorable clinical response than in the group of progressive disease. In the group of positive cytotoxicity, incidence of clinical response was significantly higher than in the group of negative cytotoxicity. A significant positive correlation was found between cytotoxicity and T cell ratio. Incidence of positive cytotoxicity tended to be higher in the cases of single OK-432 administration (6/11). Incidence of clinical response was higher in the cases of combined OK-432 and PSK administration group (4/14). In the positive cytotoxicity group, 3 examinations showed progressive disease and 5 showed no change. It has been suggested that a higher incidence of favorable clinical response is to be expected in case of positive cytotoxicity, if some therapy will be combined with the conventional immunotherapy.  相似文献   
77.
78.
BACKGROUND: Both propofol and thiamylal inhibit adenosine triphosphate-sensitive potassium (KATP) channels. In the current study, the authors investigated the effects of these anesthetics on the activity of recombinant sarcolemmal KATP channels encoded by inwardly rectifying potassium channel (Kir6.1 or Kir6.2) genes and sulfonylurea receptor (SUR1, SUR2A, or SUR2B) genes. METHODS: The authors used inside-out patch clamp configurations to investigate the effects of propofol and thiamylal on the activity of recombinant KATP channels using COS-7 cells transfected with various types of KATP channel subunits. RESULTS: Propofol inhibited the activities of the SUR1/Kir6.2 (EC50 = 77 microm), SUR2A/Kir6.2 (EC50 = 72 microm), and SUR2B/Kir6.2 (EC50 = 71 microm) channels but had no significant effects on the SUR2B/Kir6.1 channels. Propofol inhibited the truncated isoform of Kir6.2 (Kir6.2DeltaC36) channels (EC50 = 78 microm) that can form functional KATP channels in the absence of SUR molecules. Furthermore, the authors identified two distinct mutations R31E (arginine residue at position 31 to glutamic acid) and K185Q (lysine residue at position 185 to glutamine) of the Kir6.2DeltaC36 channel that significantly reduce the inhibition of propofol. In contrast, thiamylal inhibited the SUR1/Kir6.2 (EC50 = 541 microm), SUR2A/Kir6.2 (EC50 = 248 microm), SUR2B/Kir6.2 (EC50 = 183 microm), SUR2B/Kir6.1 (EC50 = 170 microm), and Kir6.2DeltaC36 channels (EC50 = 719 microm). None of the mutants significantly affects the sensitivity of thiamylal. CONCLUSIONS: These results suggest that the major effects of both propofol and thiamylal on KATP channel activity are mediated via the Kir6.2 subunit. Site-directed mutagenesis study suggests that propofol and thiamylal may influence Kir6.2 activity by different molecular mechanisms; in thiamylal, the SUR subunit seems to modulate anesthetic sensitivity.  相似文献   
79.
BACKGROUND: In terms of the temporal relationship between pancreas transplantation (PTx) and reversal of diabetic ocular complications, it has been difficult but important to determine a "point of no return." Thus, it is of great clinical interest to evaluate the efficacy of PTx on diabetic ocular complications. METHODS: A spontaneous type 2 diabetic model of Spontaneously Diabetic Torii (SDT; RT1) rats was used in the present study, and syngeneic PTx was performed. RESULTS: In the control SDT rats that received no treatment, hyperglycemia (>250 mg/dL) was developed from 25.2+/-3.9 weeks of age. Lens opacity was observed in all rats at 15 weeks after the onset of diabetes. Fluorescein angiography and immunohistochemistry detected the nonperfusion area and neovascularization in the retina at 5 weeks of diabetes. Daily insulin treatment could not prevent or reverse the ocular changes in our experiment. Fluorescein filling defect of the retinal vessels was observed at 10 weeks of diabetes. However, in the PTx rats, normoglycemia was achieved at all experimental time points. Diabetic cataract and retinopathy could have been prevented and improved if PTx had been performed at 5 weeks, but not at 10 weeks after the onset of diabetes. With PTx treatment, an inhibition of angiogenesis in the retina at 5 weeks after the onset of diabetes was demonstrated by immunohistochemistry. CONCLUSIONS: Our results indicate that the potential use of the SDT rat for diabetes study and the positive effect of PTx performed before the "point of no return" could prevent and cure diabetic ocular complications.  相似文献   
80.
Fluorinated organic compounds (FOCs), such as perfluorooctane sulfonate (PFOS), perfluoro-octanoate (PFOA), and perfluorooctane sulfonylamide (PFOSA), are widely used in the manufacture of plastic, electronics, textile, and construction material in the apparel, leather, and upholstery industries. FOCs have been detected in human blood samples. Studies have indicated that FOCs may be detrimental to rodent development possibly by affecting thyroid hormone levels. In the present study, we determined the concentrations of FOCs in maternal and cord blood samples. Pregnant women 17-37 years of age were enrolled as subjects. FOCs in 15 pairs of maternal and cord blood samples were analyzed by liquid chromatography-electrospray mass spectrometry coupled with online extraction. The limits of quantification of PFOS, PFOA, and PFOSA in human plasma or serum were 0.5, 0.5, and 1.0 ng/mL, respectively. The method enables the precise determination of FOCs and can be applied to the detection of FOCs in human blood samples for monitoring human exposure. PFOS concentrations in maternal samples ranged from 4.9 to 17.6 ng/mL, whereas those in fetal samples ranged from 1.6 to 5.3 ng/mL. In contrast, PFOSA was not detected in fetal or maternal samples, whereas PFOA was detected only in maternal samples (range, < 0.5 to 2.3 ng/mL, 4 of 15). Our results revealed a high correlation between PFOS concentrations in maternal and cord blood (r2 = 0.876). However, we did not find any significant correlations between PFOS concentration in maternal and cord blood samples and age bracket, birth weight, or levels of thyroid-stimulating hormone or free thyroxine. Our study revealed that human fetuses in Japan may be exposed to relatively high levels of FOCs. Further investigation is required to determine the postnatal effects of fetal exposure to FOCs. Key words: cord blood, fluorinated organic compounds, human, PFOA, PFOS, PFOSA, pregnancy.  相似文献   
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