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521.
Two hundred and eighty patients with serious chest injuries were treated at a service hospital during a period of 41 months. Out of 9 patients who suffered cardiac trauma S had penetrating cardiac injuries, 2 had penetrating pericardial injury and 2 patients had myocardial contusions. Myocardial contusions simulated myocardial infarction. All patients except one had polytrauma, associated injury to the lung or intra-abdominal organs. Early evacuation, resuscitation, high index of suspicion for cardiac injury and prompt surgical intervention were the keys to successful management in these patients. Thoracotomy was performed to repair the myocardial perforation and lacerated lung injuries. Associated infra-abdominal injuries were managed with laparotomy. Two patients died due to lack of cardiopulmonary bypass facilities and resistant cardiac arrhythmias. Seven patients had uneventful recovery.KEY WORDS: Heart injuries, Thoracic injuries, Traumatology, Wounds, gunshot, Wounds, nonpenetrating, Wounds, penetrating  相似文献   
522.
BACKGROUND: Traditional pleurodesis for malignant pleural effusion is performed by large-bore chest tube insertion with the instillation of sclerosing agents after the compressed lung re-expansion and pleural fluid drainage of 100-150 ml/day. This study was carried out to evaluate the possibility of rapid sclerotherapy for malignant pleural effusions by insertion of a small-bore Elecath tube (12-French) under ultrasound guidance and intrapleural injection of bleomycin 60 IU. METHODS: Twenty-six patients, with 28 cytopathologically proven malignant pleural effusions (two patients had bilateral pleural effusions) and receiving the insertion of the Elecath tube for drainage, were included in our series. This rapid and short-term sclerosing method was performed and completed by intrapleural injection of bleomycin when the pleural effusion had been clearly drained by the small-bore Elecath tube and the compressed lung had fully re-expanded on follow-up chest radiographs. RESULTS: Twenty patients with 22 pleural effusions underwent the intrapleural injection of bleomycin, with the results of pleurodesis being complete response 41% (9/22), partial response 36% (8/22) and failure 23% (5/22). Interestingly, among the 17 successful procedures of pleurodesis (complete response and partial response), 71% (12) procedures could be completed within 2 days (seven within one day and five within 2 days). The remaining unsuccessful procedures carried out on six patients without the injection of bleomycin were due to a non-re-expanded lung (n = 3) and inadequate drainage (n = 3); of these, four patients also received the large-bore chest tube insertion after the removal of the Elecath tube, but the compressed lung still could not re-expand. The complications of the bleomycin injection were fever [77% (17/22)], vomiting [14% (3/22)] and hiccup [5% (1/22)]. CONCLUSION: The method of rapid sclerotherapy for malignant pleural effusions by small-bore Elecath tube is promising, with a success rate achieving 77%, usually within 2 days.   相似文献   
523.
Klohn  PC; Bitsch  A; Neumann  HG 《Carcinogenesis》1998,19(7):1185-1190
The tumour promoting properties of carcinogenic 2-acetylaminofluorene (AAF) in rat liver are essentially unknown. We proposed that mitochondria are a target for the cytotoxic effects of 2- nitrosofluorene (NOF), a metabolite of AAF, since NOF induces a redox- cycle at complex I and complex III of the respiratory chain, and impairs respiration and oxidative phosphorylation. We now demonstrate that NOF is a potent inducer of the mitochondrial permeability transition pore (PTP) in isolated mitochondria. In the presence of Ca2+, NOF induced rapid swelling of mitochondria in a dose-dependent manner and depolarized the mitochondrial membrane. Permeability transition as well as depolarization were abolished completely by pre- incubation with the PTP inhibitor cyclosporin A. To study whether the PTP is involved in in vivo toxicity, rats were fed a diet containing AAF (0.04%) for 2 weeks. After isolation of mitochondria, permeability transition was induced by high Ca2+ concentrations (150-400 microM) or phosphate plus Ca2+. Swelling was determined as maximal rate of absorption decrease at 540 nm (delta A/delta t). Surprisingly, delta A/delta t-values of mitochondria from AAF-fed rats were significantly lower (16.3 +/- 4.8 x 10(3)/min) than of mitochondria from control animals (32.7 +/- 4.1 x 10(3)/min; P < 0.02). In the presence of phosphate (15 mM), delta A/delta t-values of mitochondria from AAF-fed rats were even lower (10% of control). Moreover, the membrane potential which was dissipated rapidly by the PTP-inducer NOF (30 microM) at a Ca2+ concentration of 80 microM in mitochondria from control animals, remained constant in mitochondria of AAF-treated rats. We therefore propose that the regulation of the PTP is altered on chronic AAF- feeding. The increased resistance of mitochondria against permeability transition may alter the threshold for apoptosis and thus suppress apoptosis. We also discuss the role of epigenetic modifications in early stages of carcinogenesis.   相似文献   
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526.
RHODA S. NARINS  MD  PC    FREDRIC S. BRANDT  MD  PA    Z. PAUL LORENC  MD  FACS    COREY S. MAAS  MD  FACS    GARY D. MONHEIT  MD  FACS    STACY R. SMITH  MD    SANDI McINTYRE 《Dermatologic surgery》2007,33(S2):S213-S221
BACKGROUND Non–animal-stabilized hyaluronic acid (NASHA) offers longer-lasting cosmetic improvement and reduced risk of hypersensitivity and requires less injection volume than bovine collagen–derived dermal fillers. Porcine collagen–derived Dermicol-P35 has low immunogenicity and has the potential to provide durability at least equivalent to that of NASHA.
OBJECTIVE The objective was to evaluate the efficacy and safety of Dermicol-P35 and NASHA for correction of nasolabial folds (NLFs).
METHODS AND MATERIALS A total of 149 subjects with moderate NLFs were randomized to receive Dermicol-P35 and NASHA on contralateral sides of the face. If needed, subjects could receive a repeat injection 2 weeks later to obtain an optimal cosmetic result (OCR).
RESULTS Significant ( p <.001) improvement in the Modified Fitzpatrick Wrinkle Scale scores relative to screening was observed after treatment with Dermicol-P35 and NASHA. Relative to the OCR visit, mean scores increased ( p <.001) over time, but there were no significant differences between treatments (+0.39 and +0.37 at 6 months; p =.626). Greater proportions of subjects experienced swelling, bruising, and pain at the NASHA site. Several subjects had more induration at the Dermicol-P35 site. There was no evidence of any adverse immunologic effect.
CONCLUSION The effectiveness of Dermicol-P35 is maintained for at least 6 months and is equivalent to NASHA for the correction of NLFs.  相似文献   
527.
Infants requiring parenteral nutrition (n = 244) were randomized to receive either 1 (group 1, n = 121) or 0.0182 micromol/kg/d (group 2, n = 123) of manganese supplementation. The whole-blood manganese and serum direct bilirubin concentrations of the infants were monitored, as was the development of cholestasis (peak serum direct bilirubin concentration >50 micromol/L). Subgroup analysis was carried out on the data of 78 infants in group 1 and 82 in group 2 who had received manganese supplementation and more than three-quarters of their total daily fluid as parenteral nutrition for >14 d. Of all the infants randomized, the high manganese group (group 1) showed a trend towards developing higher peak whole-blood manganese concentration [group 1 versus group 2: median (interquartile range): 606.0 (421.0; 1005.0) vs 566.0 (336.0: 858.0); p=0.061] and higher peak serum direct bilirubin concentration [37.0 (10.5; 122.5) vs 19.0 (8.0; 112.5); p=0.153], but the differences between the 2 groups did not reach statistical significance. The 2 groups did not differ in terms of the occurrence of cholestasis during parenteral nutrition (63/121 vs 57/123; p=0.444). Subgroup analysis of infants who had received more than three-quarters of their total daily fluid as parenteral nutrition showed, however, that the high manganese group developed significantly higher whole-blood manganese concentration [743.5 (498.0; 1211.0) vs 587.0 (438.0; 982.0); p=0.037] and serum direct bilirubin concentration [84.0 (28.0; 170.0) vs 25.5 (9.0; 117.0): p < 0.001]. Although there was no significant difference in the occurrence of cholestasis (58/78 vs 49/82; p = 0.073), more infants in the high manganese group developed a more severe degree of direct hyperbilirubinaemia, with peak serum direct bilirubin >100 micromol/L (32/78 vs 20/82; p = 0.038). Conclusion: We conclude that the pathogenesis of parenteral nutrition-related cholestasis is probably multifactorial, and that high manganese intake is a significant contributory factor.  相似文献   
528.
Cerebral vasospasm remains a serious complication of aneurysmal subarachnoid hemorrhage. Efforts in improving its clinical outcome have been focused on early diagnosis and applying effective treatment regimens. Standard diagnostic modalities currently used do not fully address this complex disease. The use of CT angiography and CT perfusion are discussed, with emphasis on its potential role in not only detecting vasospasm, but also in guiding management decisions and assessing clinical outcome.  相似文献   
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OBJECTIVE: To identify the short- and long-term therapeutic benefit of fluoroscopically guided lumbar transforaminal epidural steroid injections in patients with radicular leg pain from degenerative lumbar stenosis. DESIGN: This prospective cohort study performed at a multidisciplinary spine center. There were a total of 34 patients who met our inclusion criteria for the treatment of unilateral radicular pain from degenerative lumbar spinal stenosis who underwent fluoroscopically guided lumbar transforaminal epidural injections. Patients with radiculopathy, who did not respond to physical therapy, antiinflammatories, or analgesics, caused by degenerative lumbar stenosis and confirmed by magnetic resonance imagining received fluoroscopically guided lumbar transforaminal epidural steroid injections at the presumed symptomatic nerve root. The injectant consisted of 12 mg of betamethasone acetate and 2 ml of 1% preservative-free lidocaine HCL. Patients were evaluated by an independent observer and received questionnaires before the initial injection, at 2 mo, and at 12 mo after the injections. Questionnaires included a visual analog scale, Roland 5-point pain scale, standing/walking tolerance, and patient satisfaction scale. RESULTS: A total of 34 patients met our inclusion criteria and were followed for 1 yr. Seventy-five percent of patients had successful long-term outcome, reporting at least a >50% reduction between preinjection and postinjection pain scores, with an average of 1.9 injections per patient. Sixty-four percent of patients had improved walking tolerance, and 57% had improved standing tolerance at 12 mo. CONCLUSION: Fluoroscopically guided transforaminal epidural steroid injections may help reduce unilateral radicular pain and improve standing and walking tolerance in patients with degenerative lumbar spinal stenosis.  相似文献   
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