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991.
STATEMENT OF PROBLEM: Inadequate polymerization diminishes the physical properties of composite and compromises material strength. Newly developed light-polymerizing units (plasma arc and high intensity halogen) operate at relatively high intensity and are purported to provide optimum properties to composites in a shorter time. PURPOSE: The aim of this in vitro study was to examine the polymerization efficacy of 3 different polymerization units through a simulated ceramic restoration by determining degree of monomer conversion of a composite luting Material. MATERIAL AND METHODS: A conventional halogen light, a plasma arc light, and a high-intensity halogen light were used to polymerize a composite (Variolink II) with or without catalyst. A pressable ceramic block (5 mm in diameter, 2 mm in height) was used as an interface between the polymerizing light tip and composite. The composite/veneer combination was exposed to 2 different polymerization time protocols for each polymerization unit: (1) 20 or 40 seconds for conventional halogen light, (2) 3 or 6 seconds for plasma arc light, and (3) 10 or 20 seconds (under ramp mode) for the high-intensity halogen light. Using different light units, 120 composite specimens were evaluated (n = 5). Fourier transformation infrared spectroscopy was used to determine the level of light polymerization of the resin through the ceramic material with each of the light sources immediately after polymerization or after 24 hours. Degree of conversion was calculated as a percentage of experimentally polymerized versus maximally polymerized composite. The data were analyzed by 4-factor analysis of variance (alpha = .05). Independent t tests (alpha = .05) were used to detect differences between groups defined by the specific interacting variables. RESULTS: Degree of conversion values varied with the light source (P < .05), polymerization type (P < .05), testing time (P < .01), and exposure to each light source (P < .01). Significant interactions were present between light source and polymerization type (P = .00), light source and testing time (P = .007), and polymerization type and testing time (P = .004). The degree of conversion values were significantly higher in dual-polymerized specimens after 24 hours (P < .01), but there were no significant differences in light-polymerized specimens after 24 hours. The degree of conversion values achieved were significantly lower (P < .05) when specimens were dual polymerized by conventional halogen light and measured immediately (31.59 +/- 7.76). The degree of conversion values achieved were significantly (P < .05) higher with dual polymerization by high-intensity halogen measured after 24 hours (65.06 +/- 8.14). There were no other significant differences among groups. CONCLUSION: The highest degree of conversion values of composite were achieved with polymerization by high-intensity halogen. The plasma arc light achieved similar polymerization of composite through ceramic material in a markedly shorter period than conventional halogen light. 相似文献
992.
Enhanced frontalis sling with double-fixed, solvent-dehydrated cadaveric fascia lata allograft in the management of eye ptosis 总被引:2,自引:0,他引:2
Arslan E Demirkan F Unal S Acka G Cin I 《The Journal of craniofacial surgery》2004,15(6):960-4; discussion 965-6
The article describes an enhanced frontalis sling procedure in the management of blepharoptosis with poor or no levator function. This modified method were used in the care of three patients and based on the principal of two-point fixation of the graft material that was prepared from solvent-dehydrated cadaveric fascia lata onto the frontalis muscle. After more than 1 year of follow-up, no recurrence was noted. With no extra incision over the skin, this surgical approach could be useful in the correction of difficult ptosis cases. 相似文献
993.
BACKGROUND AND OBJECTIVES: The prognosis of sarcoidosis is highly variable, with spontaneous remission in some patients. Apoptosis may be associated with spontaneous resolution of the granulomata. CD95 (Fas), an apoptotic molecule, and CD29 and CD45RO (T-cell memory markers) are expressed at higher levels on T lymphocytes from sarcoid patients compared with normal subjects. However, the prognostic significance of CD95, CD29 and CD45RO expression in sarcoidosis is not clear. It was hypothesized that expression of CD95 would correlate with spontaneous remission. METHODS: CD29, CD45, CD45RO and CD95 expression of BAL fluid and peripheral blood (PB) lymphocytes was studied with flow cytometry in 50 patients with sarcoidosis. Results of the 15 chronic patients and 21 patients who remitted spontaneously were compared. RESULTS: BAL CD95 (59 vs 8, P = 0.002), and PB CD95 (48 vs 18, P = 0.004) and PB CD45RO (50 vs 41, P = 0.003) expression was significantly higher in patients with chronic disease compared with those with spontaneous remission. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy for these markers were: BAL CD95 (cut-off: 42.5%) 73.3%, 85.7%, 78.6%, 81.8% and 80.6%; PB CD95 (cut-off: 25%) 86.7%, 66.7%, 65%, 87.5% and 75%; and PB CD45RO (cut-off: 44.5%) 80%, 61.9%, 60%, 81.3% and 69.4%, respectively. CONCLUSION: Levels of BAL and PB CD95 and PB CD45RO were unexpectedly elevated in patients with chronic disease and may be useful in predicting prognosis in patients with sarcoidosis. Further studies with more patients are necessary to confirm the prognostic role and cut-off value for these markers. 相似文献
994.
Boke O Aker S Alptekin Aker A Sarisoy G Sahin AR 《Social psychiatry and psychiatric epidemiology》2007,42(6):457-461
The attitude of mass media is a strong determinant for stigmatisation since the majority of the society gets exposed to psychiatric
disorders via either written or visual media. In this study we explored to demonstrate the meaning attributed to the word
schizophrenia in Turkish written printed media. We screened the online sites of 12 national newspapers which allow word scanning
between the dates January 1, 2001 and May 1, 2006. The searched terms appeared in a total of 878 texts. In all twelve newspapers,
the terms “Schizophrenia”, “Schizophrene”, or “Schizophrenic” appeared once every 2.2 days. While a positive referral appeared
once in every 12.2 days, a negative referral or metaphoric use was seen once every 3.1 days. Among the 878 texts scanned,
in 491(55.9%) the searched terms appeared with reference to the disease and in 387 (44.1%) the searched terms were used metaphorically.
Considering the assumption the negative reporting may have a stronger impact than positive reporting, it is possible to suggest
that Turkish newspapers are raising stigmatisation. It is meaningful that the name of a disease is used almost with equal
frequency as a metaphoric term. In our study, higher rates of metaphoric use observed can be explained with the fact that
in Turkey the word Schizophrenia is attributed with strong negative perception. 相似文献
995.
996.
Yuceyar N Karadeniz M Erdogan M Copur A Akgun A Kumral E Ozgen G 《Clinical neurology and neurosurgery》2007,109(5):458-462
Hashimoto's encephalopathy (HE) is a rare immune-mediated encephalopathy developing in patients with high serum concentrations of anti-thyroid antibodies usually in an euthyroid or hypothyroid state. We report a 31-year-old female patient with thyrotoxic HE whose daughter has been followed up with the same diagnosis. Suboptimal response was observed with intravenous methylprednisolone (IVMP), intravenous immunoglobulin (IVIG) and plasmapheresis. Reduction of the anti-thyroid auto-antibody concentrations marked the patient's improvement in each episode. She relapsed under oral immunosuppressive therapy. After removing the thyroid tissue, full recovery has been achieved for the last 18 months. These data may contribute to clarification of the pathogenetic role of anti-thyroid antibodies in HE. Thyroidectomy can be considered as one of the treatment options especially in thyrotoxic HE patients with uncontrolled relapses. Our patient is the first reported HE case with a family history. Genetic background can underlie the etiopathogenesis of HE as is the case in other autoimmune disorders. 相似文献
997.
Mechanical trauma, thermal injury, tissue ischemia during the operation, postoperative infections, and foreign body reactions are important factors for adhesion formation. Bleeding and bile leakage after liver resections can also cause intra-abdominal adhesions. We aimed to evaluate the intra-abdominal adhesions after liver resection in rats using Ligasure and SurgRx. Twenty-seven Sprague-Dawley rats were used in the study. Three random groups were formed. Two liver lobes were resected from the middle using sutures in group A, Ligasure in group B, and SurgRx in group C. Relaparotomy was performed at postoperative day 7 to evaluate intra-abdominal adhesion formation. Adhesion formation was significantly lower in the SurgRx group compared with the suture and Ligasure groups. SurgRx and Ligasure provide effective hemostasis in liver resection without leaving foreign bodies such as clips and knots behind. SurgRx was superior to suture and Ligasure techniques in terms of adhesion formation in our model. 相似文献
998.
The aim of the study was to assess early and long-term incidence of venous complications, in both deceased donation (DD) and living-related (LR) liver transplantation (LT) in a pediatric population. Seventy-five liver transplants performed in 69 (39 boys, 30 girls) children at Ege University Hospital between 1997 and 2004 were prospectively monitored and reviewed. Age, sex, primary diagnosis, graft type, vascular complications and their management were evaluated. All patients received Doppler ultrasonographic examination both during operation and daily for the first three postoperative days and when necessary thereafter. The complications were classified as early and late presented. Thirty-three grafts (47.8%) were from DD and 36 (52.2%) were from LR donors. Recipients of DD were older than LR donors (mean age 10.5 +/- 5.1 and 5.0 +/- 0.7, respectively) (p < 0.05). Vascular complication occurrence was not statistically different between DDLT and LRLT recipients (p = 0.2), and between infants and children (p = 0.9). Overall, stenosis was more common than thrombosis. We observed hepatic artery (HA) thrombosis, in five of 75 (6.7%) transplants within 30 days post-transplant. Portal vein (PV) thrombosis and hepatic vein (HV) thrombosis were detected in six and one patients (8.7% and 1.3%), respectively. Six PV stenosis were identified (8.7%), while HA and HV-VC (vena cava) stenosis occurred in one and six patients (1.4% and 8.7%), respectively. All PV stenosis (6/33, 18.2%) and one PV aneurysm occurred in DDLT recipients while HV-VC stenosis were detected almost equally in LRLT and DDLT recipients (4/36 vs. 2/33). Except one, all PV stenosis were detected as a late complication and no intervention were needed. Stenosis of HV-VC was more common in girls (5/30 vs. 1/39) (p < 0.05) and the incidence was not different in DDLT and LRLT recipients (p = 0.8). In conclusion, overall incidences of thrombosis and stenosis formation after orthotopic liver transplantation (OLT) were 17.4% and 18.8%, respectively in our center. We suggest that in the cases with HA thrombosis manifested intra-operatively or within the early postoperative period, graft salvage was successful. Thrombosis of HA causes significant mortality. Thrombosis of PV was among the causes of mortality and morbidity. Stenosis of HV-VC could be managed by angioplasty and endovascular stenting with no significant effect to mortality. 相似文献
999.
Imaging findings were reported in an unusual case of endobronchial lipomatous hamartoma obstructing the left mainstem bronchus.
Computed tomography readily demonstrated the presence of fat density within the lesion narrowing the differential diagnosis
to endobronchial lipoma or lipomatous hamartoma. 相似文献
1000.
Icoz G Makay O Sozbilen M Gurcu B Caliskan C Firat O Kurt Z Ersin S 《World journal of surgery》2006,30(12):2165-2169
Background The goal of this study was to assess the relevance of serum D-dimer measurement as a possible reliable marker for the diagnosis
of strangulated intestinal hernia.
Methods Consecutive patients admitted with nontraumatic acute abdominal gastrointestinal disorders were recruited prospectively in
a tertiary referral hospital. The study was conducted in 159 patients between August 2002 and April 2004. D-dimer, lactate
dehydrogenase, serum amylase, and international normalized ratio (INR) levels were tested in the emergency room prior to surgical
intervention. For each patient, 15 variables, including D-dimer, were available for analysis.
Results Thirty-three (20.7%) of the 159 patients had intestinal ischemia, and 28 (85%) of these 33 patients had D-dimer level > 300
ng/ml. Plasma levels of D-dimer in patients with intestinal ischemia were significantly higher than in patients without ischemia
(P < 0.05). There were 29 (18.2%) patients in the hernia group with incarceration (n = 22) or strangulation requiring resection
(n = 7). D-dimer levels in patients requiring intestinal resection were insignificantly higher than in patients without resection
(P > 0.05). Six (85%) of the 7 hernia patients requiring resection had D-dimer levels > 360 ng/ml. The D-dimer variable correlated
best with the leukocyte count in patients with hernia requiring resection. Levels of lactate dehydrogenase, serum amylase,
and INR did not show any correlation with D-dimer levels.
Conclusions To help predict ischemic events, the increasing use of the D-dimer assay in clinical practice could be extended to patients
presenting with intestinal emergencies. An elevated D-dimer level on admission had a high sensitivity for identifying patients
with intestinal ischemia, although it had a low specificity. Whether it is predictive or preventive for resection in strangulated
intestinal hernia patients still remains a question. 相似文献