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101.
Triflavin, an Arg-Gly-Asp (RGD)-containing peptide, purified from snake venom of Trimeresurus flavoviridis, inhibits human platelet aggregation through the blockade of fibrinogen binding to fibrinogen receptors associated with glycoprotein IIb/IIIa complex. In this report, we examined the effect of triflavin on tumor cells (human hepatoma J-5)-induced platelet aggregation (TCIPA) of heparinized platelet-rich plasma (PRP). ADP-scavenger agents, apyrase (10 U/ml) and creatine phosphate (5 mM)/creatine phosphokinase (5 U/ml) did not inhibit TCIPA while hirudin (5u/ml) completely inhibited it. J-5 cells initially induced platelet aggregation, then blood coagulation occurred. J-5 cells concentration-dependently shortened the recalcification time of normal as well as Factor VIII, IX-deficient human plasmas, while it was inactive at shortening the recalcification time of Factor VII-deficient plasma, suggesting J-5 cells induced platelet aggregation through activation of extrinsic pathway, leading to thrombin formation as evidenced by the amidolytic activity on S-2238 by expressing tissue factor-like activity. Triflavin inhibited TCIPA in a dose-dependent manner (IC50, 0.02 μM). When compared on molar ratio, triflavin was approximately 30,000 times more potent than GRGDS (IC50,0.58 mM). On the other hand, GRGES showed no significant effect on TCIPA, even its concentration was raised to 4 mM. Additionally, the monoclonal antibodies, raised against glycoprotein IIb/IIIa complex (i.e., 7E3 and 10 E5) inhibited J-5 TCIPA. In conclusion, we suggest the inhibitory effect of triflavin on J-5 TCIPA may be chiefly mediated by the binding of triflavin to the fibrinogen receptor associated with glycoprotein IIb/IIIa complex on platelet surface membrane.  相似文献   
102.
Summary A phase II study of high-dose ifosfamide in hepatocellular carcinoma was conducted among 17 Chinese patients. The dose of ifosfamide used was 2.5 g/m2 daily given as a continuous infusion for 5 days. In all, 15 patients were evaluable for tumour response. There was no complete or partial responder. The treatment was well tolerated. The most frequent toxicity was alopecia, which occurred in 11 patients, and 5 patients developed mild haematological toxicity. There was no evidence of liver or bladder toxicity. Overall, 14 patients were evaluable for survival. The median survival was 92 days (range, 30–568 days). We conclude that high-dose ifosfamide is well tolerated but ineffective in hepatocellular carcinoma in Chinese patients.  相似文献   
103.
Extensive intraductal component (EIC) has been reported to have a prominent role in local recurrence after treatment of early-stage breast cancer with lumpectomy and irradiation. Pathologic specimens from 250 breasts (245 patients) treated between June 1982 and June 1990 with lumpectomy, immediate (boost) interstitial iridium-192 to 15-20 Gy, and external-beam irradiation to the entire breast to 45-50 Gy were reviewed. EIC was present in 61 breasts. At a median follow-up period of 58 months (range, 14-110 months), there were 10 recurrences in the 250 treated breasts. Of these 10, three were in patients from the group with EIC. The 10-year actuarial recurrence rates in breasts with and without EIC were 9.1% and 5.2%, respectively. The difference between the two rates was not significant. If an immediate boost with interstitial iridium is used in therapy, the influence of EIC on local failure is insignificant.  相似文献   
104.
From February 1990 to January 1991, 19 cases of hydronephrosis in children of less than one year of age were managed at Mackay Memorial Hospital. In the majority of these patients, there were evident causes such as ureteropelvic junction stenosis, ureterovesical reflux or a posterior urethral valve for which definite therapeutic measures were performed. However, some cases had no obvious origins and the hydronephrosis was speculated to be from nonobstructive or physiologic dilatation of the kidneys. The conventional tools, such as intravenous pyelogram or renal ultrasound, which comprise the mainstay of diagnosis, provide limited information on renal functional status. Recent introduction of the Tc-99m diethylene triamine penta-acetic acid (DTPA) diuretic renal scan has enabled us to distinguish between obstructive and nonobstructive hydronephrosis and helps us to determine whether or not surgery is necessary. In the past year, eight patients with hydronephrosis of less than one year of age were diagnosed as nonobstructive after a series of evaluations using renal ultrasound, voiding cystourethrography (VCUG) and Tc-99m DTPA diuretic renal scan. Follow-up studies by echography or DTPA renal scan revealed spontaneous resolution of the dilated collecting systems in these cases and confirms our belief that some hydronephrosis in neonates and infants may resolve spontaneously and may just be a manifestation of physiologic change during development. The value of the Tc-99m DTPA diuretic renal scan in the diagnosis of obstructive uropathy is discussed.  相似文献   
105.
106.
The in vitro effects of liposomes on HaCaT human keratinocytes were studied with regard to their uptake, lipid fluidity and proliferation of the cells. Oligolamellar liposomes, prepared from soya bean phospholipids, had a mean size of 150 mm and consisted predominantly of phosphatidylcholine (83%) and phosphatidylethanolamine (10%) and the fatty acids comprised mainly linoleic acid (66%) or other unsaturated fatty acids. After 6 and 24 h of incubation with 1 and 0.1% w/v of liposomal lipids, phase-contrast microscopy revealed marked cytoplasmic vacuolization of the cells. Keratinocytes treated with the liposomes contained aggregations of multilaminated lipid material without delimiting cell membranes. The cellular lipid fluidity (reciprocal of diphenylhexatriene fluorescence polarization P-value) correlated with liposomal concentration and incubation time. A significant elevation of lipid fluidity (P less than 0.05) was observed with 1 and 0.1% liposomes after 1 h of incubation (81.8 +/- 4.7 and 95.7 +/- 1.2% of control P value) and for 0.01% liposomes after 3 h (96.2 +/- 1.5%). Maximum fluidity occurred after 48 h of exposure to 1% liposomes (42.1 +/- 3.1%). Exposure to liposomal lipids for 24 and 48 h resulted in suppressed cell proliferation with 50% inhibition concentrations (IC50), being 0.06% for incorporation of [3H]-thymidine. 0.08% for [14C]-amino-acid incorporation and greater than 1% for protein content per well after 24 h of exposure. The cells were able to proliferate and lipid fluidity returned to normal within 7 days following discontinuation of incubation with liposomal lipids.  相似文献   
107.
俞林 《浙江预防医学》2005,17(12):51-51
随着<母婴保健法>和<浙江省儿童听力筛查管理办法>等法律法规的相继出台和实施,儿童听力筛查已纳入了妇幼保健机构的服务项目.为了解我市儿童听力障碍的发病情况,我所于2004年2~3月对辖区内12所幼儿园382名新入托学龄前儿童开展了听力筛查,现报告如下.  相似文献   
108.
BACKGROUND AND PURPOSE: Uterine cramping pain is related to prostaglandins, which are mediated by cyclooxygenase. However, it is unknown whether the analgesic effects of the non-selective cyclooxygenase inhibitor tenoxicam are different between primiparous and multiparous women. This placebo-controlled, double-blind study compared the analgesic effect of tenoxicam on post-cesarean uterine cramping pain in primiparous and multiparous women. METHODS: Forty primiparous women and 40 multiparous women who were scheduled for elective cesarean delivery were allocated into the following 4 groups: saline-primipara (SP) group, tenoxicam-primipara (TP) group, saline-multipara (SM) group, and tenoxicam-multipara (TM) group. Saline or 20 mg tenoxicam was intravenously injected immediately after clamping of the umbilical cord. All patients received patient-controlled analgesia for postoperative pain control. Resting wound pain, uterine cramping pain, morphine consumption, and morphine-related side effects were evaluated at 4 and 24 hours after surgery. RESULTS: At 24 hours after surgery, tenoxicam-related relief of uterine cramping pain was 2.1 in primiparous women (visual analog scale: SP 5.6 (4.4-6.8) minus TP 3.5 (2.2-4.9); p < 0.01). The tenoxicam-related morphine-sparing effect was 14 mg (45%) in primiparous women (SP 31.4 mg (23.9-38.8) minus TP 17.4 mg (11.6-23.2); p < 0.01). The tenoxicam-related relief of uterine cramping pain and tenoxicam-related morphine-sparing effect were not significant in multiparous women. CONCLUSIONS: This study revealed that the analgesic effect of tenoxicam on post-cesarean uterine cramping pain is greater in primiparous women than in multiparous women. Further studies are required to determine whether a higher dosage of tenoxicam is beneficial to reduce uterine cramping pain in multiparous women.  相似文献   
109.
Usually, a drug is loaded onto the metallic surface of a medical device by applying a polymer layer containing the drug. Unfortunately, polymer coatings on the metallic surface may exhibit numerous problems after implantation, such as late thrombosis, inflammation, and restenosis. Current research was conducted to investigate whether a suitable oxide layer can be used as a polymer-free platform for drug loading, especially for cardiovascular stents. The loading of heparin onto, as well as eluting of heparin from, the amorphous oxide film on the 316LVM stainless steel wire was confirmed by experimental studies using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), electron spectroscopy for chemical analysis (ESCA), high-performance liquid chromatography (HPLC), and activated clotting time (ACT). Evidence shows that amorphous oxide can be an ideal substitute for the polymer coating of drug-loaded stents to minimize metallic corrosion, inflammation, late-thrombosis, and restenosis.  相似文献   
110.
目的:分析74例更换起搏器时电极导线的各项参数的变化并探讨导线更换指标。方法:本组年龄12~87(62.8±18.4)岁,其中病窦综合征45例,房室传导阻滞29例,均为单腔VVI起搏。结果:至测量时原心室起搏电极导线的埋置时间60~148(97.4±22.8)月,首次埋置时起搏阈值为(0.48±0.24)V,更换时为(1.29±0.64)V(P(0.01),增加0.81V,增幅为168%,首次植入时R波幅为(7.8±3.6)mV,更换时为(5.9±3.4)mV(P(0.05)。植入时电极导线阻抗为(664±122)Ω,更换时阻抗为(726±148)Ω,增幅9.3%(P(0.05)。7例因起搏阈值大于2.0 V或阻抗大于1 250Ω而重新植入电极导线。原电极导线使用率为90.5%。结论:埋置起搏电极导线8~9年后,90.5%原电极导线仍在可使用的范围内,能否支持到再次更换需进一步随访。  相似文献   
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