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11.
Ilkay Koray Bayrak Zafer Ozmen Mehmet Selim Nural Murat Danaci Baris Diren 《Korean journal of radiology》2008,9(3):250-257
OBJECTIVE: It has been advocated that a reduced injection volume with highly concentrated (1 M) contrast material can produce a sharper bolus peak and an increased intravascular first-pass gadolinium concentration when compared with the use of a lower concentration (0.5 M). A higher concentration would also cause a reduction in dose. The purpose of our study was to test the use of a low dose (0.05 mmol/kg) of gadobutrol in magnetic resonance renography and angiography and compare the findings with a dose of 0.1 mmol/kg. MATERIALS AND METHODS: One-hundred-thirty-four patients referred for magnetic resonance angiography for suspected renovascular disease participated in the study. Contrast enhanced MR renography and angiography were performed after administration of a bolus of 0.1 mmol/kg or 0.05 mmol/kg gadobutrol in randomized patients. The relative signal intensity-time curves of the aorta, peripheral cortex and parenchyma, were obtained. Two radiologists evaluated the angiographic images and evaluated the quality of angiography. RESULTS: The signal intensity with a low dose of gadobutrol was significantly lower in early phases, in the peripheral cortex (for 36, 54, 72 and 90 seconds), the parenchyma (for 36, 54, 72 seconds) and the aorta (for 18, 36, 54, 72 seconds). The decreases in the early phase obtained with a low dose of gadobutrol caused blunter time intensity curves. The difference in the quality scores of the readers for the angiographic images for the use of the two different doses was not statistically significant (p > 0.05). CONCLUSION: A lower dose of gadobutrol can be used for MR renal angiography, but for MR renography the normal dose should be used. 相似文献
12.
Törer N Nursal TZ Calişkan K Ezer A Colakoğlu T Moray G Haberal M 《Acta chirurgica Belgica》2010,110(4):467-470
PURPOSE: to analyze the effect of anxiety and depression on the postoperative complications and length of hospitalization of patients with breast cancer. Beck's Depression Inventory (BDI) and Hospital Anxiety and Depression Scale (HADS) were filled out by the patients pre-operatively. Patients were asked to rate their pain by the visual analogue scale (VAS) after surgery. Age, seroma volume, day of drain withdrawal, complications, and pathological stages were noted. The median age of 49 patients with the diagnosis of breast cancer was 51 (36-80). There was a significant correlation between the pain score and Beck, HADS, HADS (anxiety) and HADS (depression) (8 hours ; p = 0.021, 0.001, 0.004, 0.005 and 24 hours ; p = 0.005, 0.012, 0.006, 0.120). The mean HADS depression score in those patients with complications was 9.1 +/- 4.2 and that of patients with no complications was 6.6 +/- 3.1 (p = 0.047). The mean hospital stay of patients with a normal HADS score (< 19) was 2.9 +/- 1.1 days, whilst that of patients with an abnormal HADS score was 3.8 +/- 1.2 days (p = 0.016). Patients with abnormal HADS anxiety and abnormal HADS (total) scores had an earlier stage of breast cancer (p = 0.077, p = 0.063). The psychological status of breast cancer patients effects their postoperative recovery period and it is easy to diagnose these patients by some brief questionnaires. 相似文献
13.
Bambakidis NC Feiz-Erfan I Horn EM Gonzalez LF Baek S Yüksel KZ Brantley AG Sonntag VK Crawford NR 《Journal of neurosurgery. Spine》2008,8(2):143-152
OBJECT: The stability provided by 3 occipitoatlantal fixation techniques (occiput [Oc]-C1 transarticular screws, occipital keel screws rigidly interconnected with C-1 lateral mass screws, and suboccipital/sublaminar wired contoured rod) were compared. METHODS: Seven human cadaveric specimens received transarticular screws and 7 received occipital keel-C1 lateral mass screws. All specimens later underwent contoured rod fixation. All conditions were studied with and without placement of a structural graft wired between the skull base and C-1 lamina. Specimens were loaded quasistatically using pure moments to induce flexion, extension, lateral bending, and axial rotation while recording segmental motion optoelectronically. Flexibility was measured immediately postoperatively and after 10,000 cycles of fatigue. RESULTS: Application of Oc-C1 transarticular screws, with a wired graft, reduced the mean range of motion (ROM) to 3% of normal. Occipital keel-C1 lateral mass screws (also with graft) offered less stability than transarticular screws during extension and lateral bending (p < 0.02), reducing ROM to 17% of normal. The wired contoured rod reduced motion to 31% of normal, providing significantly less stability than either screw fixation technique. Fatigue increased motion in constructs fitted with transarticular screws, keel screws/lateral mass screw constructs, and contoured wired rods, by means of 19, 5, and 26%, respectively. In all constructs, adding a structural graft significantly improved stability, but the extent depended on the loading direction. CONCLUSIONS: Assuming the presence of mild C1-2 instability, Oc-C1 transarticular screws and occipital keel-C1 lateral mass screws are approximately equivalent in performance for occipitoatlantal stabilization in promoting fusion. A posteriorly wired contoured rod is less likely to provide a good fusion environment because of less stabilizing potential and a greater likelihood of loosening with fatigue. 相似文献
14.
Traumatic diaphragmatic hernias, when diagnosed many years after the traumatic event, are observed in about 10% of diaphragmatic injuries. Due to coexisting injuries and the silent nature of diaphragmatic injuries, the diagnosis is easily missed or difficult. The medical records of 26 patients, who were treated for diaphragmatic hernias during the last 20 years, were analysed retrospectively. The patients were divided into acute phase and late-presenting groups, in whom emergency surgery and elective intervention were performed respectively. Chest radiography was diagnostic in 34.6% (n=9) of patients. 92.3% of the hernias were on the left side, while the most common herniated organs were the stomach (31.8%) and the colon (27.2%). Coexisting injuries were recorded in 38.4% (n=10) of the patients. Primary repair was predominantly used (92.3%). The hospitalisation period was longer in the late-presenting group (24.1±18.8 vs. 14.3±7.7 days). Two deaths occurred in the late-presenting group. Diaphragmatic hernia should be suspected in all blunt abdominal trauma patients. Prompt surgical repair is the treatment of choice in all traumatic diaphragmatic hernias. 相似文献
15.
Teke Z Aytekin FO Kabay B Yenisey C Aydin C Tekin K Sacar M Ozden A 《World journal of surgery》2007,31(9):1835-1842
Background Pyrrolidine dithiocarbamate (PDTC) is a low-molecular-weight thiol antioxidant and potent inhibitor of nuclear factor-κB (NF-κB)
activation. It has been shown to attenuate local harmful effects of ischemia/reperfusion (I/R) injury in many organs. In recent
animal studies, a delaying effect of remote organ I/R injury on the healing of colonic anastomoses has been demonstrated.
In this study we investigated whether PDTC prevents harmful systemic effects of superior mesenteric I/R on left colonic anastomosis
in rats.
Methods Anastomosis of the left colon was performed in 40 rats randomly allocated into the following four groups: (1) Sham-operated
group (group I, n = 10)—simultaneously with colonic anastomosis, the superior mesenteric artery and collateral branches divided from the celiac
axis and the inferior mesenteric artery were isolated but not occluded. (2) Sham+PDTC group (group II, n = 10)—identical to sham-operated rats except for the administration of PDTC (100 mg/kg IV bolus) 30 minutes prior to commencing
the experimental period. (3) I/R group (group III, n = 10)—60 minutes of intestinal I/R by superior mesenteric artery occlusion. (4) PDTC-treated group (group IV, n = 10)—PDTC 100 mg/kg before and after the I/R. On postoperative day 6, all animals were sacrificed, and anastomotic bursting
pressures were measured in vivo. Tissue samples were obtained for investigation of anastomotic hydroxyproline (HP) contents,
perianastomotic malondialdehyde (MDA) levels, myeloperoxidase activity (MPO), and glutathione (GSH) level.
Results There was a statistically significant decrease in anastomotic bursting pressure values, tissue HP content and GSH level, along
with an increase in MDA level and MPO activity in group III, when compared to groups I, II, and IV (p < 0.05). However, PDTC treatment led to a statistically significant increase in anastomotic bursting pressure values, tissue
HP content and GSH level, along with a decrease in MDA level and MPO activity in group IV (p < 0.05).
Conclusions This study showed that PDTC treatment significantly prevented the delaying effect of remote organ I/R injury on anastomotic
healing in the colon. Further clinical studies are needed to clarify whether PDTC may be a useful therapeutic agent for increasing
the safety of the anastomosis during particular operations where remote organ I/R injury occurs. 相似文献
16.
Mehmet Nusret Demircan Alparslan Asir Ahmet Cetinkal Nursal Gedik Ahmet Murat Kutlay Ahmet Çolak Sedat Kurtar Hakan Simsek 《European spine journal》2007,16(7):983-986
The proinflammatory mediator (PIM) levels were assessed in surgically removed samples of herniated cervical intervertebral discs. The objective of this study was to investigate if there is a correlation between the levels of PIMs in disc material and myelopathy associated with cervical intervertebral disc herniation and spondylosis. The role of proinflammatory mediators in the degeneration of intervertebral disc and the inflammatory effects of disc herniations on radicular pain has been previously published. However, the possible relationship between PIMs and myelopathy related to cervical disc herniation and spondylosis has not been investigated before. Thirty-two patients undergoing surgery for cervical disc herniation and spondylosis were investigated. Surgically obtained disc materials, stored at 70 degrees C, were classified into two groups: cervical disc herniation alone or with myelopathy. Biochemical preparation and solid phase enzyme amplified sensitivity immunoassay (ELISIA) analysis of the samples were performed to assess the concentration of mediators in the samples. Very similar values of interleukin-6 were found in both groups whereas the concentrations of mediators were significantly higher in myelopathy group. This study has demonstrated that PIMs are involved in cervical intervertebral disc degeneration with higher concentrations in the samples associated with myelopathy. 相似文献
17.
Aytekin FO Teke Z Aydin C Kabay B Yenisey C Sacar S Demir EM Tekin K 《American journal of surgery》2007,193(6):723-729
BACKGROUND: Tempol (Sigma-Aldrich, Steinheim, Germany) is a stable piperidine nitroxide of low molecular weight that permeates biologic membranes and scavenges superoxide anions in vitro. In recent animal studies, the delaying effect of intraperitoneal sepsis on the healing of colonic anastomoses has been shown. In this study we aimed to investigate the effects of Tempol on the healing of colonic anastomoses in the presence of polymicrobial sepsis. METHODS: Anastomosis of the left colon was performed on the day after cecal ligation and puncture (CLP) in 30 rats that were divided into 3 groups: sham-operated control (laparotomy and cecal mobilization, group I, n = 10), CLP (group II, n = 10), Tempol-treated group (30 mg/kg intravenously before the construction of colonic anastomosis, group III, n = 10). On postoperative day 6, all animals were killed and anastomotic bursting pressures were measured in vivo. Tissue samples were obtained for further investigation of anastomotic hydroxyproline (HP) contents, perianastomotic myeloperoxidase (MPO) activity, malondialdehyde (MDA), and glutathione (GSH) levels. RESULTS: There was a statistically significant increase in MPO activity and MDA levels in the CLP group (group II), along with a decrease in GSH levels, anastomotic HP contents, and bursting pressure values when compared with controls (group I). However, Tempol treatment led to a statistically significant increase in anastomotic bursting pressure values, tissue HP contents, and GSH levels, along with a decrease in MPO activity and MDA levels in group III (P < .05). CONCLUSIONS: This study showed that Tempol treatment significantly prevented the delaying effect of CLP-induced polymicrobial sepsis on anastomotic healing in the left colon. Further clinical studies are needed to clarify whether Tempol may be a useful therapeutic agent to increase the safety of the anastomosis during particular surgeries in which sepsis-induced organ injury occurs. 相似文献
18.
BACKGROUND: Complicated hydatid cyst of the thorax is important to the clinical approaches and treatment methods in hydatid disease. The aim of this study was to evaluate the problems of complicated pulmonary hydatid cyst, including choice of surgical methods, diagnostic clues and to discuss the inherent risks of medical therapy and the delay of surgical treatment in pulmonary hydatid disease. METHODS: Between 2002 and 2006, 40 operations were carried out in 37 patients whose diagnoses were complicated hydatid cyst. The surgical approach was a posterolateral thoracotomy in all patients; a phrenotomy in two patients and a thoracoabdominal approach in one patient and two-stage bilateral thoracotomy in four patients. The preferred surgical treatment procedure was cystotomy and modified capitonnage, which was carried out in 26 patients (70%). Other procedures included a cystotomy in five (14%) and decortication in six (16%) patients. Segmentectomy was carried out in 1 (3%), and wedge resection in four patients (11%). RESULTS: In 25 patients (67.5%), there were single hydatid cysts; whereas 12 patients (32.5%) had multiple cysts. Eleven patients had preoperative hydatid cyst history. Iatrogenic rupture of an intact hydatid cyst occurred in three patients. Extrathoracic involvement was apparent in 10 patients (27%). Intrathoracic but extrapulmonary involvement was apparent in six patients (16%). The morbidity ratio was 5%; there was prolonged air leak and atelectasis in one patient each. The mortality ratio was 3% (one patient). The average hospitalization duration for all patients was 5.7 days (range, 3-17 days). The mean follow up was 18.4 months with no recurrence. CONCLUSION: Complicated hydatid cyst may have different clinical manifestations and may present radiologically as a primary lung tumour. In patients with suspicious lung masses owing to endemic area, history of a hydatid cyst or contralateral or extrathoracic hydatid cyst involvement at the same time should indicate a complicated pulmonary hydatid cyst. Preoperative anthelmintic therapy must be avoided owing to the risk of perforation. Treatment of a complicated hydatid cyst differs from that of an intact hydatid cyst. Anatomic resection may be necessary owing to destroyed lung tissue secondary to suppuration from a hydatid cyst; however, parenchymal preserving surgery is preferable in an uncomplicated hydatid cyst. A modified capitonnage method is recommended for complicated hydatid cyst treatment as it has a low morbidity rate. 相似文献
19.
Ercan Malkoc Bilal Fırat Alp Zafer Demirer Ali Guragac Furkan Dursun Ferhat Ates 《Renal failure》2014,36(10):1564-1569
Objectives: Extracorporeal shock wave lithotripsy (ESW) induces renal damage by excessive production of free oxygen radicals. Free Oxygen radicals cause cellular injury by inducing nicks in DNA. The enzyme poly(adenosine diphosphate-ribose) polymerase (PARP) involved in the process of repair of DNA in damaged cells. However, its activation in damaged cells can lead to adenosine triphosphate depletion and death. Thus, we designed a study to evaluate the efficacy of 3-aminobenzamide (3-AB), a PARP inhibitor, against extracorporeal shock wave induced renal injury. Methods: Twenty-four Sprague-Dawley rats were divided into three groups: control, ESW, ESW?+?3-AB groups. All groups except control group were subjected to ESW procedure. ESW?+?3-AB group received 20?mg/kg/day 3-aminobenzamide intraperitoneally at 2?h before ESW and continued once a day for consecutive 3 days. The surviving animals were sacrificed at the 4th day and their kidneys were harvested for biochemical and histopathologic analysis. Blood samples from animals were also obtained. Results: Serum ALT and AST levels, serum neopterin and tissue oxidative stress parameters were increased in the ESW group and almost came to control values in the treatment group (p?0.05, ESW vs. ESW?+?3-AB). Histopathological injury score were significantly lower in treatment group than the ESW group (p?0.05, ESW vs. ESW?+?3-AB). Conclusion: Our data showed that PARP inhibition protected renal tissue against ESW induced renal injury. These findings suggest that it would be possible to improve the outcome of ESW induced renal injury by using PARP inhibitors as a preventive therapy. 相似文献
20.
Tarik Zafer Nursal Hakan Yakupoglu Nurten Renda Erhan Hamaloglu Iskender Sayek Demirali Onat 《Journal of investigative surgery》2013,26(2):61-68
Gastrointestinal system anastomoses, especially colonic anastomoses, have significant morbidity and mortality despite recent technical improvements. Besides regulating the circadian rhythm, the pineal gland and its main neurohormone product melatonin have widespread actions in the organism. The purpose of this study was to investigate the effects of pinealectomy on the healing of colonic anastomoses. One hundred male albino Wistar rats were used in this study. The rats were separated into three groups: control, pinealectomy, and sham groups. In the control group, only colonic resection and anastomoses were performed. Following pinealectomy, colonic anastomosis was performed 2 weeks later on one half and 2 months later on the other half of the pinealectomy group. Only craniotomy was performed on the sham group, and the rats were separated and evaluated like the pinealectomy group. Colonic anastomoses were evaluated on postanastomotic day 3 and 7 by measuring the bursting pressure and the hydroxyproline levels in the anastomotic segments. There was no difference in the bursting pressure measurements between the groups on both postoperative day 3 and 7. Although hydroxyproline levels were different between groups on both postanastomotic days 3 and 7, it has been observed that neither normal nor anastomotic hydroxyproline levels influenced the anastomotic bursting pressure measurements. The percent deviation from the normal values was compared in the anastomotic segments, and no differences were found regarding the bursting pressure and hydroxyproline levels. It was concluded that pinealectomy has no effect on the healing of colonic anastomoses. 相似文献