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91.
基于开发的计算机取样系统,采用SPSR法脉冲动态测试KD306型耐硫甲烷化催化剂的有效扩散系数。线性化和参数估值的结果吻合较好,证实:线性化简化是合理的,参数估值是可用于有效扩散系数。KD306型耐硫甲烷化催化剂的曲折因子为7.2。 相似文献
92.
Objective: To observe the effects of Xin’an capsule (XAC) on experimental ventricular arrhythmia (EVA) in animals and to explore the possible mechanism.Methods: Three types of animal arrhythmic model (ventricular arrythmia in guinea pigs induced by Ouabin, in rats caused by reperfusion after ligation of descending anterior branch of coronary artery and by CaCl2) were used to study the effects of XAC on ventricular arrhythmia (VA).Results: After XAC treatment, the dosage of Ouabin needed for inducing ventricular premature beat (VPB), ventricular tachycardia (VT) and ventricular fibrillation (VF) increased in guinea pigs. The sustaining time of reperfusion induced VT and total occurrence of ventricular arrhythmias decreased. XAC also showed an effect in increasing CaCl2 dosage needed to cause VA, and decreased the occurrence of VF and death in rats 相似文献
93.
肺癌患者血浆GST-π水平测定及其临床意义 总被引:1,自引:0,他引:1
探讨肺癌患者手术和化疗前后血浆GST-π水平的变化。方法应用RIA方法对32例手术和26例化疗的肺癌患者进行动态检测。结果无论手术还是化疗前后患者血浆GST-π水平均明显高于正常对照组。 相似文献
94.
Free fatty acids impair hepatic insulin extraction in vivo 总被引:11,自引:0,他引:11
Wiesenthal SR Sandhu H McCall RH Tchipashvili V Yoshii H Polonsky K Shi ZQ Lewis GF Mari A Giacca A 《Diabetes》1999,48(4):766-774
Hyperinsulinemia is a common finding in obesity and results from insulin hypersecretion and impaired hepatic insulin extraction. In vitro studies have shown that free fatty acids (FFAs), which are often elevated in obesity, can impair insulin binding and degradation in isolated rat hepatocytes. To investigate whether FFAs impair hepatic insulin extraction (E(H)) in vivo, either saline (SAL) or 10% Intralipid (0.03 ml x kg(-1) x min(-1)) plus heparin (0.44 U x kg(-1) x min(-1)) (IH) was infused into normal dogs to elevate FFA levels. Insulin was infused intraportally at 18 pmol x kg(-1) x min(-1) for 150 min (period A, high insulin dose), and then at 2.4 pmol x kg(-1) x min(-1) for another 150 min (period B, low insulin dose). After the low portal insulin dose, additional insulin was infused peripherally at 8.4 pmol x kg(-1) x min(-1) for 120 min (period C) to assess the clearance of insulin from the peripheral plasma. In 16 paired experiments, FFA levels were 1,085 +/- 167, 1,491 +/- 240, 1,159 +/- 221 micromol/l (IH) and 221 +/- 44, 329 +/- 72, 176 +/- 44 micromol/l (SAL) in periods A, B, and C, respectively. Peripheral insulin levels were greater with IH (P < 0.001) than with SAL in all periods (1,620 +/- 114, 126 +/- 12, 1,050 +/- 72 pmol/l for IH vs. 1,344 +/- 168, 96 +/- 4.2, 882 +/- 60 pmol/l for SAL). Glucose clearance was impaired by IH in all periods (P < 0.05), whereas glucose production was slightly increased by IH during period B. Peripheral insulin clearance (Cl) and E(H) were calculated from the insulin infusion rate and insulin concentration data in each period by taking into account the nonlinearity of insulin kinetics. Cl was lower (P < 0.01) with IH (9.6 +/- 0.6, 12.0 +/- 0.9, 10.2 +/- 0.6 ml x kg(-1) x min(-1)) than with SAL (11.2 +/- 1, 13.6 +/- 0.7, 11.9 +/- 0.9 ml x kg(-1) x min(-1)) in periods A, B, and C. E(H) was also lower (P < 0.05) with IH (25 +/- 4, 40 +/- 5, 32 +/- 5%) than with SAL (30 +/- 2.8, 47 +/- 3, 38 +/- 3%). We conclude that FFAs can impair hepatic insulin extraction in vivo at high and low insulin levels, an effect that may contribute to the peripheral hyperinsulinemia of obesity. 相似文献
95.
Assadi FK McCue P Jefferis S Shi M Beckman DA 《Pediatric nephrology (Berlin, Germany)》1999,13(9):812-815
The safety of cysteamine after renal transplantation and during pregnancy is an important issue, since girls with cystinosis
are in better health on cysteamine therapy and thus more likely to become pregnant. In the first study, cysteamine was given
to pregnant rats on days 6.5–18.5 post conception in oral doses of 0, 37.5, 75, 100, and 150 mg/kg per day. The dams were
sacrificed on day 20.5, the fetal kidneys removed and prepared for histological examination. In the second study, cysteamine
was given to dams on days 6.5–19.5 post conception in oral doses of 0, 37.5, 50, and 75 mg/kg per day. Dams were allowed to
give birth naturally and pups were given cysteamine on days 4–21 to yield the same oral doses of cysteamine given to the dam.
Renal function was evaluated on day 35. Histological examination of fetal kidneys revealed no changes even in kidneys from
fetuses with growth retardation and malformations. Furthermore, there were no alterations in renal function in offspring on
day 35. These findings demonstrate that cysteamine therapy does not affect renal development in the rat. Further investigations
will be required to prove whether cysteamine therapy has the potential to affect renal development in the human.
Received: 25 September 1998 / Revised: 17 November 1998 / Accepted: 13 December 1998 相似文献
96.
Ambulatory urodynamic monitoring of external urethral sphincter behavior in chronic prostatitis patients 总被引:3,自引:0,他引:3
Aim: To study the behavior of external urethral sphincter in chronic prostatitis (CP) patient under natural filling.Methods: Twenty-one CP patients and 17 normal volunteers were involved in the study. Both the patients andvolunteers underwent ambulatory urodynamic monitoring (AM) and conventional medium filling cystometry (CMG).Urodec 500 was used for AM and Menuet for CMG. AM findings from CP patients were compared with those fromnormal volunteers, and the results from AM were compared with those from CMG. Results: In AM, the restingand voiding external urethral sphincter (EUS) pressures and maximum urethral closure pressures (MUCP) weresignificantly higher in CP patients [ ( 121.5 ±10.3) and (85.6±3.5) cm water, respectively ] than in normalvolunteers [ (77.6±11.4) and (10.3±1.6) cm water, respectively)]. Conclusion: The behavioral changes ofEUS in CP patients included spasm and instability of EUS, which were demonstrated using AM under natural filling;the findings were also in accord with the res 相似文献
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100.
Shi DY Zhang F Kryger Z Komorowska-Timek E Lineaweaver WC Buncke HJ 《Journal of reconstructive microsurgery》1999,15(7):539-545
Recent evidence has shown that changes in blood viscosity and marked increases in both platelet count and fibrinogen concentration occur after exposure to hyperbaric oxygen (HBO). The purpose of the present study was to address whether repeated HBO therapy would increase either hematocrit or platelet count, and to determine if these changes would influence the patency of the microvascular anastomosis, as well as anastomotic healing. Eighty femoral arteries from 40 rats were divided into four groups (n = 10), and arterial anastomoses were performed on normal arteries in the first two groups, and on crushed arteries in the second two groups. One of the normal artery groups and one of the crushed artery groups received repeated HBO treatments for 5 days. Anastomotic patency rates, platelet count, hematocrit, and breaking strength were recorded. Among the results of this study were that: (1) there was no difference in patency rate following HBO treatment in both the normal and crushed artery groups; (2) platelet count was significantly higher following HBO treatment in the groups with the undamaged arteries; (3) breaking strength was significantly increased following HBO treatment in the groups with the crushed arteries. The authors concluded that HBO therapy may be useful in improving the healing of microvascular anastomoses in vessels that have undergone crush injury. Although HBO treatment results in an increased platelet count, this does not influence anastomotic patency. 相似文献