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31.
Researchers and other stakeholders continue to express concern about the failure of randomized clinical trials (RCT) in subarachnoid hemorrhage (SAH) to show efficacy of new treatments. Pooled data may be particularly useful to generate hypotheses about causes of poor outcomes and reasons for failure of RCT in SAH, and strategies to improve them. Investigators conducting SAH research collaborated to share data with the intent to develop a large repository of pooled individual patient data for exploratory analysis and testing of new hypotheses relevant to improved trial design and analysis in SAH. This repository currently contains information on 11,443 SAH patients from 14 clinical databases, of which 9 are datasets of recent RCTs and 5 are datasets of prospective observational studies and hospital registries. Most patients were managed in the last 15 years. Data validation and quality checks have been conducted and are satisfactory. Data is available on demographic, clinical, neuroimaging, and laboratory results and various outcome measures. We have compiled the largest known dataset of patients with SAH. The SAHIT repository may be an important resource for advancing clinical research in SAH and will benefit from contributions of additional datasets.  相似文献   
32.
鸟氨酸脱羧酶的生理病理特点及其药物研究概况   总被引:2,自引:0,他引:2  
鸟氨酸脱羧酶(ornithinedecarboxylase,ODC)是多胺代谢中的关键酶,广泛存在于人体和动物各组织细胞内,其中对肠细胞的增生、移行和分化起重要作用.机体调节因素比较复杂.在黏膜损伤性疾病及某些癌前病变等细胞大量增生的病理情况下ODC的表达发生改变,可以作为这些疾病分期、预后及药物作用靶点或疗效的指标.寻找对ODC有作用的药物对于治疗其相关疾病是非常有意义的.  相似文献   
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Cisplatin is one of the most active single agents in advanced squamous cell carcinoma of the cervix and is synergistic with 5-fluorouracil in the laboratory. The Gynecologic Oncology Group has conducted a phase II trial in which cisplatin at 50 mg/ml2 given intravenously on Day 1 was combined with 5-fluorouracil 1000 mg/m2 daily given as a 24-hr infusion on Days 1-5. Treatment was repeated every 21 days. Fifty-five patients were treated with this regimen, resulting in seven complete remissions (12.7%) and five partial remissions (9.1%). The median survival was 6.4 months. Toxic effects of grade 2 or greater were leukopenia in 10 patients (18.2%), thrombocytopenia in 2 patients (3.6%), gastrointestinal effects in 25 patients (45.5%), and renal effects in 1 patient (1.8%). On the basis of these results, the cisplatin and 5-fluorouracil regimen does not appear to have any advantage over cisplatin alone in advanced cervical cancer.  相似文献   
37.
A phase II trial of ifosfamide (isophosphamide, NSC 109724) and mesna (2-mercaptoethane sodium sulfonate, NSC 113891) in women with advanced or recurrent mixed mullerian tumors of the uterus was conducted by the Gynecologic Oncology Group. The starting dose of ifosfamide was 1.5 gm/m2 daily, intravenously, for 5 days. The starting dose of ifosfamide was reduced 1.2 gm/m2 daily in patients who had received prior radiotherapy. Mesna was given intravenously immediately and at 4 and 8 hours after the administration of ifosfamide. Each mesna dose was 20% of the total daily dose of ifosfamide. Twenty-nine patients are evaluable for toxicity, and 28 patients are evaluable for response. Twenty-one patients had received prior abdominal hysterectomy, and eight patients had prior radiotherapy. Thirteen tumors were homologous and 15 heterologous. Gynecologic Oncology Group grade 3 or 4 granulocytopenia occurred in seven (25%) patients and two (7.1%) had grade 3 or 4 thrombocytopenia. Two patients (7.1%) had grade 3 or 4 neurotoxicity. One patient experienced lethargy and confusion that responded to discontinuation of the ifosfamide. A second patient developed progressive cerebellar dysfunction, left hemiparesis, and coma. This patient died after 3 days of therapy. Complete responses were seen in five (17.9%) patients and partial responses occurred in four (14.3%) patients for a total response rate of 32.2%. These results indicate that ifosfamide is an unusually active drug in patients with advanced or recurrent mixed mullerian tumors of the uterus. Studies with combination regimens incorporating ifosfamide are warranted. The toxicity of ifosfamide in Gynecologic Oncology Group studies is being evaluated retrospectively.  相似文献   
38.
Patients with postmolar nonmetastatic gestational trophoblastic disease were entered into this Gynecologic Oncology Group study to determine the relationship of efficacy and toxicity to a rapidly escalating dose of weekly intramuscular methotrexate. The treatment was initiated at 40 mg/m2 weekly of intramuscular methotrexate. If no major toxicity was encountered, the weekly dose was escalated 5 mg/m2 at 2-week intervals until a maximum dose of 50 mg/m2 per week was achieved. Complete response was defined as three normal beta-hCG values measured on consecutive weeks. Forty-six of sixty-two (74%) evaluable patients had a complete response to this regimen. Duration of therapy ranged from 3 to 16 weeks with a median of 7 weeks. No major toxicity occurred. Eight patients experienced leukopenia at a median of 3200/microliters (range 2100-3900). Two patients had platelet nadirs of 128,500 and 131,000. Only 50% (8/16) of the nonresponders subsequently responded to second-line 5-day methotrexate every 2 weeks. Fifteen of the sixteen weekly intramuscular methotrexate failures ultimately had complete responses after treatment with subsequent chemotherapy. In this study, second-line therapy results support administration of another agent such as dactinomycin rather than 5-day methotrexate. This higher dose (1.36 relative dose intensity to median complete response) of weekly intramuscular methotrexate therapy (40 mg/m2) is no more effective and of similar toxicity to a lower-dose regimen (30 mg/m2) reported earlier.  相似文献   
39.
Objective: To report ventilation strategies, survival and complications in 39 outborn infants treated with high frequency oscillatory ventilation (HFOV).
Methodology Data were collected prospectively between 1 May 1992 and 31 December 1993 on all infants treated with HFOV who had severe respiratory failure despite optimal conventional ventilation.
Results Twenty-eight out of 39 (72%) survived. Of the 15 infants with birthweights <1500g, eight survived. Best survival rates were for infants with pulmonary interstitial emphysema with air leak (4/5) and for infants of birthweight >1500g with hyaline membrane disease (8/8), and meconium aspiration syndrome (7/7). Three infants deteriorated while on HFOV and required extracorporeal membrane oxygenation. Complications were: (i) development of pulmonary interstitial emphysema (1); (ii) recurrence of pneumothorax (3); (iii) hypotension (2); and (iv) bronchopulmonary dysplasia (9). One of the eight infants weighing <1500g who received HFOV in the first week of life developed periventricular haemorrhage.
Conclusion The initial results of HFOV for severe respiratory failure were encouraging although a learning curve was encountered with its introduction.  相似文献   
40.
Long-term results of the Blom-Singer speech rehabilitation procedure   总被引:1,自引:0,他引:1  
We report a 64% long-term success rate in our series of 66 patients who have undergone the tracheoesophageal puncture (TEP) procedure with follow-up ranging from one to 3 1/2 years. Poor motivation and compliance were the most common factors noted in patients who failed to obtain or maintain tracheoesophageal speech. Other problems causing failure were technical problems relating to the TEP and medical problems. The success rate in the last 24 cases of our series has improved to 83%. The "collared" prosthesis, more careful patient selection, and emphasis on a team approach seem to be important factors for the higher success rate. The Blom-Singer TEP procedure is a safe, simple, and effective means of alaryngeal communication for selected patients.  相似文献   
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