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71.
Bülent Gül Sezer Kulaçoglnu Dr. Muammer Yükse Handan Dogan Ali Ihsan Ökten 《Neurosurgical review》1997,20(1):59-61
Esthesioneuroblastoma is an uncommon malignant neoplasm that arises from olfactory mucosa, often with intracranial extension.A case report of the youngest victim in the literature (2-year-old boy) is presented. 相似文献
72.
Pathological changes in testes and liver of male albino rats after dermal exposure to DDVP insecticide. 总被引:1,自引:0,他引:1
Exposure of male albino rats to DDVP insecticide at sublethal dose of 30 mg/kg/day through dermal painting for a period of 90 days didn't show any intoxication symptoms or mortality. However, cytopathological changes in testicular and liver tissues were evident. There was a positive correlation between the degree of cellular damage and the period of insecticide administration. In general, damages were prominent in rats treated for 30 days or more. Histological examination of testes showed degenerative seminiferous tubules and fewer leydig cells. Hepatic cells were congested, atrophied and showed different stages of necrobiotic changes. This suggests a great care and caution for workers during different phases of DDVP insecticide handling. 相似文献
73.
Bone scintigraphy in tuberculous sacroiliitis 总被引:1,自引:0,他引:1
Radionuclide bone imaging is becoming increasingly important in the evaluation of musculoskeletal pain of uncertain cause. A case in which Tc-99m MDP bone imaging was employed to investigate complaints of low back pain is presented. Scan abnormalities directed clinicians towards appropriate further workup and diagnosis of unilateral tuberculous sacroiliitis. 相似文献
74.
Jerrold S. Meyer Mark Grande Kenneth Johnson Syed F. Ali 《International journal of developmental neuroscience》2004,22(5-6):261
3,4-Methylenedioxymethamphetamine damages fine serotonergic fibers and nerve terminals in adult organisms. Developing animals seem to be less susceptible to this effect, possibly due to a lack of drug-induced hyperthermia. We tested this hypothesis by producing hyperthermia in neonatal rats for 2 h after each of twice-daily MDMA (10 mg/kg s.c.) or saline injections administered from postnatal days 1–4. Other drug-treated and control litters were maintained at normothermic temperatures following injection. Changes in forebrain serotonergic innervation were assessed at postnatal day 25 (serotonin transporter binding and serotonin levels), postnatal day 60 (serotonin transporter binding), and 9 months of age (serotonin transporter immunohistochemistry). We also determined the influence of MDMA treatment on apoptotic activity by means of immunohistochemistry for cleaved caspase-3 at postnatal day 5. The hippocampus showed significant MDMA-related reductions in serotonergic markers at postnatal day 25 and postnatal day 60. At 9 months, there was no effect of prior MDMA exposure on serotonin transporter-immunoreactive fiber density in the hippocampus; however, significant reductions in fiber density were observed in two neocortical areas and a hyperinnervation was found in the caudate-putamen and nucleus accumbens shell. MDMA treatment also produced a two-fold increase in the number of cleaved caspase-3-immunoreactive cells in the rostral forebrain and hippocampus. All of these effects were completely independent of pup body temperature. These findings demonstrate that neonatal MDMA administration exposure stimulates apoptotic cell death in various forebrain areas and also leads to a long-term reorganization of the forebrain serotonergic innervation. Consequently, offspring of MDMA-using women may be at heightened risk for abnormal neural and behavioral development. 相似文献
75.
Ali Ghoz Ehab Kheir Anil Kotru Karim Halazun David Kessel Jai Patel J J Peter A Lodge 《Hepatobiliary & Pancreatic Diseases International》2007,(3)
BACKGROUND:Spontaneous hemoperitoneum of hepato- biliary origin is commonly due to hemorrhage from a liver tumor.It is rarely caused by spontaneous rupture of aneurysm in visceral arteries. METHODS:We report an unusual case of hemoperitoneum caused by rupture of cystic artery pseudoaneurysm,and also outline the approach to its management through surgical and radiological methods. RESULTS:In our patient,the pseudoanurysm was initially treated with percutaneous thrombin injection.However this method of treatment failed after initial success.The pseudoanurysm was finally obliterated successfully using microcoil embolization. CONCLUSIONS:The mainstay of treatment of cystic artery pseudoaneurysm is cholecystectomy and ligation of the aneurysm.Recent publications showed success in using microcoil embolisation.In this case we also outline the use of percutaneous thrombin injection as a definitive treatment method and discuss its success or failure as a new method of treatment. 相似文献
76.
P Chaturvedi U C Chaturvedi R Mukherjee 《International journal of experimental pathology》1992,73(6):773-782
The helper T cells (TH) generated in dengue type 2 virus (DV) infection of mice produce a soluble helper cytokine (HF) which enhances the clonal expansion of DV-specific IgM antibody plaque forming cells (PFC). The present study was undertaken to investigate the mechanism of transmission of the helper signal from TH and HF to B cells. It was observed that TH could transmit the helper signal to B cells by direct cell to cell contact, but HF could not do so without the presence of live macrophages (M phi). HF was adsorbed by both heat killed and live M phi but the former could not transmit it to B cells. Both the polypeptide chains of HF bind to M phi. HF remains on the surface of M phi and can be retrieved completely by contact with B cells for 40 min. The helper signal from TH or HF-adsorbed M phi could not be transmitted to B cells when they were separated from each other by a cell impermeable membrane. The enhancement of PFC count is greater when the signal is transmitted by HF-adsorbed M phi as compared to that by TH alone. Thus, even with lower frequency of TH a significant number of B cells may be triggered with the help of HF and M phi. The findings thus show that the DV-specific helper signal could be transmitted only by a close physical contact of the plasma membranes of the signal presenting cells (TH or HF-adsorbed M phi) and B cells. 相似文献
77.
118 multibacillary leprosy patients with differential manifestations were studied for the antigens they expressed at MHC loci to investigate the role of human leukocyte antigens in the differential response to the same causative agent. While the lepromatous leprosy (LL) patients showed a significant increase of Bw60, DR2, DRw8 and DQw1, borderline lepromatous (BL) patients had Bw52, DR9 and DQw7 significantly more often as compared to the normal controls. A comparison of LL, BL and mid-borderline (BB) patients showed a significantly higher frequency of Bw60 in LL patients as compared to the BL. However, Bw52, Bw53, DR9 and DQw7 were found significantly more often in the BL patients as compared to the LL patients but the difference failed to reach significance after pc. A comparison of HLA antigens in BB patients with those of either the LL or BL patients did not show any significant differences. 相似文献
78.
Effect of aerosol challenge with sensitising antigen on the permeability of the surface of the rat trachea in life. 下载免费PDF全文
A rat model of immediate pulmonary hypersensitivity was used to investigate the permeability changes in the tracheal epithelium produced by aerosol challenge with antigen. The rats were sensitised by the intraperitoneal injection of antigen (dinitrophenyl (DNP19) ovalbumin). Sensitised and control animals were then challenged for 60 minutes with an aerosol of the same antigen, which also contained the electron dense pore marker lanthanum. Histological examination and x ray probe microanalysis showed a greater intercellular concentration of lanthanum in the tracheal epithelium in sensitised than in control animals. The results show that in sensitised rats increased intercellular penetrance of antigen can occur after antigen challenge. 相似文献
79.
Rupak Mukherjee Preecha Laohakunakorn M. Charles Welzig Kathryn S. Cowart J. Philip Saul 《Journal of interventional cardiac electrophysiology》2003,9(3):309-315
Background: Radiofrequency (RF) lesion size in vitro is positively correlated with applied power and catheter tip temperature. However, the relation between RF lesion size, power, and tip temperature in vivo remains unclear. We hypothesized that due to flow, anatomy and tip contact effects in vivo, increased tip temperature would be inversely related to applied power and RF lesion size.
Methods: RF lesions were created on the endocardium of 16 pigs using 5, 6, and 7 Fr catheters. The ablation generator was set to achieve a temperature of 70°C. RF lesions were created in different regions of the heart so as to encompass a wide range of blood flow and catheter movement conditions. RF lesions were measured acutely (DIMEN, mm) and correlated with average power applied (POWER, W), and average tip temperature (TEMP, °C). The POWER and TEMP relation was also examined.
Results: For TEMPs below 55°C, the power output from the generator was typically maximized at 50 W. At TEMPs above 55°C, POWER decreased exponentially with increasing TEMP {POWER = 50 – exp(-((41-TEMP)/7)), r = 0.98, p < 0.05}. Further, DIMEN tended to be inversely related to TEMP (Slope: –0.07 ± 0.04, r = –0.15, p = 0.07); but, was positively related to POWER (Slope: 0.04 ± 0.02, r = 0.23, p < 0.05). These relations varied by tip size and estimated local blood flow characteristics.
Conclusion: In vivo, variable tissue contact and flow yield DIMEN-POWER-TEMP relations opposite to those found in vitro. These counterintuitive results suggest that maximum in vivo RF lesion size is achieved when power is maximized at tip temperatures between 50 and 60°C. 相似文献
80.
Murat Ozeren Nehir Sucu Lülüfer Tamer Barlas Aytacoglu Ozgür Bayri Ali D?nda? Lokman Ayaz Murat Dikmengil 《Pharmacological research》2005,52(3):258-263
BACKGROUND AND AIM OF STUDY: Cardioplegic arrest remains the method of choice for myocardial protection in cardiac surgery. Caffeic acid phenethyl ester (CAPE) prevents lipid peroxidation induced by ischemia-reperfusion injury and has a potent antioxidant property. We investigated the advantages of CAPE supplemented cardioplegic solution (St. Thomas' Hospital cardioplegic solution No.: 2) on the antioxidant defense system of myocardium against ischemia-reperfusion injury. MATERIAL AND METHODS: Isolated rat hearts were mounted on a nonrecirculating type of Langendorff apparatus. The hearts were arrested for 60 min with cardioplegic solution given at 20-min intervals and then reperfused for 15 min. The hearts were divided into three groups. Cold saline (0.9%, 4 degrees C) in group 1, St. Thomas' Hospital solution in group 2 and CAPE added St. Thomas' Hospital solution in group 3 were used as the cardioplegic solution. Krebs-Henseleit buffer solution was used for reperfusion. The tissues were examined biochemically for oxidative stress. RESULTS: Significant differences among the three groups existed in tissue myeloperoxidase (MPO), catalase (CAT), Na+-K+ ATPase activity and in the concentrations of malonydealdehyde (MDA) and 3-nitrotyrosine (3-NT). Group 2 showed significant changes in MPO (P = 0.04), Na+-K+ ATPase enzyme activity (P = 0.02) and the levels of MDA (P = 0.004) and 3-NT (P = 0.01) in comparison with group 1. Group 3 efficiently reduced MDA levels (P = 0.004) and also led to significant decrease in levels of MPO (P = 0.006), 3-NT (P = 0.01) and Na+-K+ ATPase activity (P = 0.01) and increase in the level of CAT (P = 0.004) in comparison with group 1. Significant changes were also found in the levels of MDA (P = 0.03), MPO (P = 0.04) and CAT (P = 0.009) in comparison between groups 2 and 3. CONCLUSIONS: We demonstrated that the administration of CAPE into cardioplegic solutions improves the antioxidant defense system of rat heart during the ischemia-reperfusion injury. 相似文献