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91.
The aim of this study was to assess the radiologic and clinical outcome when beta-tricalcium phosphate is used as a bone graft substitute to backfill the fibular defect that is created by harvesting the fibula. Fourteen patients who had fibula resections to be used as bone grafts for bone tumor resections were assessed radiographically. Callus formation bridging the beta-tricalcium phosphate was seen in 12 of 14 patients at an average of 1.4 months after surgery. In these 12 patients the beta-tricalcium phosphate mostly was absorbed and replaced by newly formed bone at an average of 9.3 months after surgery. In all children, beta-tricalcium phosphate was replaced by newly formed bone at an average of 3.2 months after surgery. Only one adult patient had complete regeneration of the fibula. Few patients had continuity between the regenerated fibula and the native fibula. In one patient in whom free vascularized fibula was harvested, regeneration of the fibula was not observed. Clinical functional outcome was not correlated with successful fibula regeneration and union with the native fibula, as determined using radiographs. The results of the study suggest that, in children, regeneration of the fibula by implanting beta-tricalcium phosphate into a bone defect can reduce morbidity of the fibula harvest sites.  相似文献   
92.
Purpose Oral midazolam is frequently used to treat children, but its effect on recovery from anesthesia is controversial. This study was designed to evaluate the effect of flumazenil on reversal of midazolam during recovery from sevoflurane-induced anesthesia in children who underwent caudal analgesia compared to those who did not.Methods A series of 60 children 1–8 years of age, with an American Society of Anesthesiologists (ASA) physical status of 1 or 2, who were scheduled to undergo herniorrhaphy were randomly assigned to one of four groups: group 1, control/placebo; group 2, control/flumazenil; group 3, caudal/placebo; group 4, caudal/flumazenil. After oral administration of midazolam 0.5 mg · kg−1, anesthesia was induced and maintained with sevoflurane and nitrous oxide in oxygen via a face mask with spontaneous ventilation. The time from the discontinuation of anesthetics to emergence was recorded, and at the time of discharge from the operating room each patient’s recovery characteristics were assessed using a three-point scale.Results Emergence from anesthesia was significantly less agitated in the group of children who underwent caudal analgesia without flumazenil compared to the other three groups. Flumazenil shortened the time to emergence regardless of the application of caudal analgesia, and caudal analgesia delayed the time to emergence regardless of flumazenil administration.Conclusion Caudal analgesia and avoiding the use of flumazenil synergistically resulted in the emergence from anesthesia in a less agitated state for children who underwent herniorrhaphy after oral midazolam premedication.This study was presented in part at the International Anesthesia Research Society’s 77th Clinical and Scientific Congress, New Orleans, March 22, 2003  相似文献   
93.
SUMMARY: Advanced glycation end products (AGEs) have been found to accumulate in the amyloid deposits, skin and plasma of haemodialysis patients (HD), implicating the possible involvement of AGE-modified protein in pathogenesis in dialysis-related amyloidosis. Pentosidine, an AGE cross-link, is a specific marker for AGEs. Plasma pentosidine levels in HD patients were increased dramatically. In the present study, plasma pentosidine, fructoselysine, advanced oxidation protein products (AOPP) and glutathione peroxidase (GSHPx) levels were measured to elucidate the role of oxidative stress in pentosidine formation in nondiabetic HD patients. Plasma pentosidine did not correlate with fructoselysine; plasma AOPP levels were significantly higher than those in normal subjects (201.45 ± 57.93 vs. 55.91 ± 6.57 μmol/L, P <0.001) and correlated positively with plasma pentosidine in HD patients ( r =0.52, P <0.005); plasma GSHPx levels were significantly lower than those in normal subjects (168.40 ± 65.08 vs. 348.87 ± 86.10 U/I, P <0.001) and correlated negatively with plasma pentosidine ( r =0.54, P <0.001) in HD patients. Decreased GSHPx levels may lead to the accumulation of hydrogen peroxide. These findings implicate the involvement of oxidative stress in the accelerated formation of pentosidine in uraemia and suggest that pentosidine could be considered as an oxidative stress biomarker to estimate the degree of oxidative-stress-mediated protein damage.  相似文献   
94.
We report a case of compartment syndrome caused by femoral arterial cannulation during cardiopulmonary bypass. A 62-year-old man who had been diagnosed as acute aortic dissection (type I) received a operation of partial arch replacement with reconstruction of brachiocephalic and left carotid arteries. Compartment syndrome was noticed just after the operation, which was caused by long-term ischemia during femoral arterial cannulation combined with poor collateral circulation by the dissection of iliac arteries. The emergency fascitomy was performed, therefore, he could be discharged without any complications. It is concluded that in case of acute aorte aortic dissection, the back-flow of blood should be checked at the time of femoral arterial cannulation, and whenever the back-flow is poor, some procedures should be added to increase distal blood flow.  相似文献   
95.
We present a surgical case of a 35-year-old man with aortitis. He had been performed the reconstruction of the right common carotid artery with a saphenous vein graft at 23 years old for his ruptured aneurysm by aortitis. The aortic valve replacement and CABG (LITA to LAD, SVG to D1 and SVG to RCA) were performed for aortic regurgitation and aneurysms of coronary arteries two years ago. The diastolic murmur was first heard at 18 months after the operation. The echocardiography on admission showed an abnormal movement of the prosthetic valve with perivalvular leakage. At the second operation, the valve dehiscence was observed. Although the tissues around the dehiscence was friable and edematous, there wre no signs of vegetation nor abscess formation. His aortic root was replaced with a cryopreserved aortic allograft conduit. His postoperative course was uneventful and aortography revealed neither aortic regurgitation nor stenosis of the coronary artery or SVGs. We think the softness of the allograft valve ring is favorable in valve detachment cases due to not only infection but also aortitis, to prevent redetachment.  相似文献   
96.
To assess the feasibility and analyze the short-term outcomes of laparoscopic intracorporeal rectal transection with double-stapling technique anastomosis, a review was performed of a prospective registry of 67 patients who underwent laparoscopic sigmoidectomy and anterior resection with intracorporeal rectal transection and double-stapling technique anastomosis between July 2001 and January 2004. Patients were divided into 3 groups: sigmoid colon/rectosigmoid carcinoma, upper rectal carcinoma, and middle/lower rectal carcinoma. A comparison was made of the short-term outcomes among the groups. The number of cartridges required in bowel transection was significantly increased in patients with middle/lower rectal carcinoma, and significant differences were observed in the length of the first stapler cartridge fired for rectal transection. Furthermore, mean operative time and blood loss were also significantly greater in the middle/lower rectum group; however, complication rates and postoperative course were similar among the 3 groups. No anastomotic leakage was observed. Laparoscopic intracorporeal rectal transection with double-stapling technique anastomosis can be performed safely without increased morbidity or mortality.  相似文献   
97.
Sato Y  Honda Y  Iwamoto J  Kanoko T  Satoh K 《BONE》2005,36(4):721-726
Risk of hip fractures in stroke patients is higher than that in a reference population. Hyperhomocysteinemia is regarded as a risk factor for ischemic stroke. The high prevalence of osteoporosis among patients with homocystinuria suggests that hyperhomocysteine may also increase the risk of fractures. To determine the association between homocysteine concentration and the risk of hip fractures, we studied a cohort of stroke patients with hemiplegia. Age-adjusted incidence rates of a hip fracture were calculated for quartiles of homocysteine concentrations. Cox proportional-hazard regression was used to calculate hazard ratios for quartiles of homocysteine levels. The initial enrolment of 433 hemiplegic patients with ischemic stroke, older than 65 years old, were followed for up to 10 years. The mean plasma homocysteine concentration at the enrolment was 14.1 +/- 5.2 micromol/L. There were 33 hip fractures among men and 46 among women during the mean follow-up period of 9.0 years. The age-adjusted incidence rates per 1000 person-years for hip fractures increased almost linearly from 2.89 in the lowest to 27.87 in the highest quartiles of homocysteine levels. We conclude that hyperhomocysteinemia is one of the risk factors for hip fractures in stroke patients.  相似文献   
98.
The hepatic arterial buffer response (HABR) is an intrinsic regulatory mechanism of the hepatic artery (HA) that compensates for reductions in portal venous (PV) blood flow. Whether this response is maintained in patients with cirrhosis (LC) is unclear. The aim of the present study was to examine whether HABR is maintained in patients with LC using direct blood flow measurements. PV and HA blood flow were intraoperatively measured and compared in patients with (LC group, n = 39) or without (control group, n = 22) cirrhosis at baseline (baseline HABR) and after PV clamping (acute HABR) using an ultrasound transit-time flowmeter. In contrast to the proportional relationship between the baseline PV and HA blood flow observed in the control group, HA blood flow and the HA-PV flow ratio increased when PV blood flow decreased in the LC group, suggesting that the baseline HABR had already been activated. Acute HABR, evaluated by the absolute and relative changes in HA blood flow and by the buffer capacity, was blunted in the LC group (P < 0.001, P < 0.01, and P = 0.01, respectively). An association between the degree of acute HABR impairment and the level of baseline HABR activation (HA-PV flow ratio) could not be confirmed in the LC group. In conclusion, the baseline HABR appears to be continuously activated in patients with LC; this phenomenon probably results in the impairment of the acute HABR.  相似文献   
99.
BACKGROUND CONTEXT: In patients with spinal osteoporosis, the early achievement and maintenance of a biological bond between the pedicle screw and bone is important to avoid screw loosening complications. There are few reports of in vivo investigations involving biomechanical and histological evaluations in the osteoporotic spine. PURPOSE: To evaluate the effect of hydroxyapatite (HA)-coating on the pedicle screw in the osteoporotic lumbar spine and to investigate the relationship between resistance against the screw pull-out force and bone mineral density (BMD) of the vertebral body. STUDY DESIGN/SETTING: Mechanical and pathological investigations in the lumbar spine. METHODS: Two 24-month-old female beagle dogs were fed a calcium-free dog chow for 6 months after ovariectomy (OVX). BMD (in g/cm2) was measured by dual energy X-ray absorptiometry at pre-OVX and 6 months after OVX. Pedicle screws were placed from L1 to L6 at 6 months after OVX. Twenty-four pure titanium cortical screws (Synthes, #401-114) were used as pedicle screws (Ti-PS). Of these, 12 screws had HA-coating (HA-PS). The HA-PS screws were inserted into the right pedicles and the Ti-PS were inserted into the left pedicles. Ten days after this procedure, the lumbar spines were removed en bloc for screw pull-out testing and histological evaluation. RESULTS: The mean BMD value of the lumbar vertebrae 6 months after the OVX was 0.549+/-0.087 g/cm2, which was significantly less than the pre-OVX mean BMD of 0.603+/-0.092 g/cm2 (p < 0.001). The mean resistance against the pull-out force for the HA-PS was significantly greater at 165.6+/-26.5N than in the Ti-PS (103.1+/-30.2N, p < .001). The histological sections in the HA-PS clearly revealed new bone bonding with the apatite coating but only fibrous tissue bonding in the Ti-PS. CONCLUSIONS: The results of this study showed that the resistance to the pull-out force of HA-PS is 1.6 times that of Ti-PS. Furthermore, HA-PS has superior biological bonding to the surrounding bone, as early as 10 days after surgery in this osteoporotic spine model. Thus, in patients with osteoporosis, coating of the pedicle screw with HA may provide better stability and bonding between the pedicle screw and bone in the early postoperative period.  相似文献   
100.
BACKGROUND: Endoscopic thoracic sympathectomy has been considered an effective treatment for palmar hyperhidrosis. However, the extent of resection has not been determined in terms of efficacy and complications. We compared the efficacy and complications of 2-ganglion and single-ganglion resection in patients with palmar hyperhidrosis. METHODS: From 1995 to 2000, 75 patients underwent resection of thoracic ganglion T2 and T3. From 2000 to 2003, 67 patients underwent resection of only the T2 ganglion. Eighty of the 142 patients (56%) answered a detailed questionnaire, the results of which were analyzed. RESULTS: Gender, age, family history, and distribution of sweating were similar in both groups. Recurrence rates 1 and 2 years after endoscopic thoracic ganglionectomy were between 0% and 3% in T2 and T3 resection, and between 15% and 19% in T2 resection only. In the combined T2 and T3 resection group, 100% of patients noticed compensatory sweating; in T2 resection, 90% of patients noticed compensatory sweating. As for rates of satisfaction, T2 and T3 resection was superior to T2 resection. CONCLUSIONS: High recurrence rates of palmar hyperhidrosis after single-ganglion resection are reported in the present study. Two-ganglion resection is a superior surgical method to prevent recurrence of palmar hyperhidrosis.  相似文献   
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