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81.
Assessment of skeletal maturity is an integral part of interceptive diagnosis and treatment planning. The present day methods of skeletal maturity assessment like the hand-wrist radiographs or cervical vertebrae radiographs are expensive, require elaborate equipment and accounts for high radiation exposure, especially for growing children. The present study was thus undertaken to provide a simple and practical method of skeletal maturity assessment using the developmental stages of the middle phalanx of the third finger (MP3) as seen on an IOPA film taken using a standard dental x-ray machine. The results of the study showed that this simple method was highly reliable and could be used as an alternative method to assess the skeletal maturity of growing children.  相似文献   
82.
BRAF and RAS mutations in human lung cancer and melanoma   总被引:22,自引:0,他引:22  
BRAF encodes a RAS-regulated kinase that mediates cell growth and malignant transformation kinase pathway activation. Recently, we have identified activating BRAF mutations in 66% of melanomas and a smaller percentage of many other human cancers. To determine whether BRAF mutations account for the MAP kinase pathway activation common in non-small cell lung carcinomas (NSCLCs) and to extend the initial findings in melanoma, we screened DNA from 179 NSCLCs and 35 melanomas for BRAF mutations (exons 11 and 15). We identified BRAF mutations in 5 NSCLCs (3%; one V599 and four non-V599) and 22 melanomas (63%; 21 V599 and 1 non-V599). Three BRAF mutations identified in this study are novel, altering residues important in AKT-mediated BRAF phosphorylation and suggesting that disruption of AKT-induced BRAF inhibition can play a role in malignant transformation. To our knowledge, this is the first report of mutations documenting this interaction in human cancers. Although >90% of BRAF mutations in melanoma involve codon 599 (57 of 60), 8 of 9 BRAF mutations reported to date in NSCLC are non-V599 (89%; P < 10(-7)), strongly suggesting that BRAF mutations in NSCLC are qualitatively different from those in melanoma; thus, there may be therapeutic differences between lung cancer and melanoma in response to RAF inhibitors. Although uncommon, BRAF mutations in human lung cancers may identify a subset of tumors sensitive to targeted therapy.  相似文献   
83.
This study was undertaken to identify and characterize the anti-aggregatory protein factor present in rat polymorphonuclear leukocytes (PMNs) supernatant. Since the purified protein exhibited sequence homology to beta globin, globin was also isolated from rat blood by acid-acetone precipitation and was purified on Superdex-75 column in FPLC. Elution of rat globin on the gel filtration column yielded two peaks of approximately 60 and 30 kDa as observed in the PMNs supernatant. Purity of globin and eluted fractions was further evaluated by SDS-PAGE. Platelet aggregation induced by agonists viz. adenosine-5'-diphosphate (ADP; 2-5 microM), arachidonic acid (AA; 10 microM), A23187 (2.50 microg/ml) was inhibited by globin and the purified fractions. ADP-induced rise in intracellular calcium levels and expression of CD62 on the platelets were reduced by both globin and active fraction of PMNs supernatant. Results obtained suggest that globin or globin-related protein present in the PMNs supernatant inhibits platelet aggregation response.  相似文献   
84.
Five hundred unselected newborn babies delivered in the Department of Obstetrics and Gynaecology, Unit II of SGBT Hospital attached to Government Medical College, Amritsar during April 2000 to October 2000 were examined for cutaneous lesions daily for the first five days after birth. Different cutaneous lesions were seen in 474(94.8%) newborns. The physiological skin changes observed in order of frequency were Epstein pearls in 305(61%), Mongolian spot in 301(60.2%), superficial cutaneous desquamation in 200(40%), icterus in 128(25.6%), milia in 119(23.8%), sebaceous gland hyperplasia in 107(21.4%), occipital alopecia in 94(18.8%), lanugo in 72(14.4%), peripheral cyanosis in 47(9.4%), breast hypertrophy in 29(5.8%) and miniature puberty in 28(5.6%) newborns. Of the transient non-infective skin diseases, erythema toxicum neonatorum was observed most commonly in 105(21%), followed by miliaria rubra in 103(20.6%) and acne neonatorum in 27(5.4%) newborns. The naevi and other developmental defects in the descending order were salmon patch in 69(13.8%), congenital melanocytic noevi in 10(2%), accessory tragi in 3(0.6%), spina bifida in 2(0.4%), hydrocephalus in 1(0.2%) and poliosis in 1(0.2%) newborns. Cradle cap was the only dermatitis observed in 50(10%) newborns. One (0.2%) case each of Harlequin ichthyosis and labial cyst was seen.  相似文献   
85.
PURPOSE: To define outcome data and prognostic criteria for patients with metastatic renal cell carcinoma (RCC) treated with interferon-alfa as initial systemic therapy. The data can be applied to design and interpretation of clinical trials of new agents and treatment programs against this refractory malignancy. PATIENTS AND METHODS: Four hundred sixty-three patients with advanced RCC administered interferon-alpha as first-line systemic therapy on six prospective clinical trials were the subjects of this retrospective analysis. Three risk categories for predicting survival were identified on the basis of five pretreatment clinical features by a stratified Cox proportional hazards model. RESULTS: The median overall survival time was 13 months. The median time to progression was 4.7 months. Five variables were used as risk factors for short survival: low Karnofsky performance status, high lactate dehydrogenase, low serum hemoglobin, high corrected serum calcium, and time from initial RCC diagnosis to start of interferon-alpha therapy of less than one year. Each patient was assigned to one of three risk groups: those with zero risk factors (favorable risk), those with one or two (intermediate risk), and those with three or more (poor risk). The median time to death of patients deemed favorable risk was 30 months. Median survival time in the intermediate-risk group was 14 months. In contrast, the poor-risk group had a median survival time of 5 months. CONCLUSION: Progression-free and overall survival with interferon-alpha treatment can be compared with new therapies in phase II and III clinical investigations. The prognostic model is suitable for risk stratification of phase III trials using interferon-alpha as the comparative treatment arm.  相似文献   
86.
PURPOSE: We describe the response to conventional or high-dose salvage chemotherapy in patients with advanced seminoma who experience disease progression after receiving first-line platinum-based treatment. PATIENTS AND METHODS: Twenty-seven patients with progressive, advanced, pure seminoma were treated with salvage chemotherapy. Fifteen patients were treated with conventional-dose cisplatin-and-ifosfamide combination chemotherapy. Twelve patients were treated with high-dose chemotherapy followed by autologous stem-cell rescue. RESULTS: Fifteen patients (56%) achieved a complete response (CR), nine achieved CR with a conventional-dose cisplatin and ifosfamide program, and six experienced CR after high-dose chemotherapy. Fourteen patients (52%) are alive and disease-free, with 13 (48%) continuously disease-free at a median follow-up of 72 months. Twelve (57%) of 21 patients whose pretreatment tumors were studied morphologically were found to have seminoma with atypia. Eight patients underwent resection after salvage chemotherapy; six with histologic findings of necrotic debris/fibrosis alone are alive and disease-free at last follow-up. Both patients with viable seminoma found at surgery died of disease. CONCLUSION: Most patients with advanced seminoma are cured with standard first-line programs of cisplatin and etoposide with or without bleomycin. A small minority of patients with pure seminoma have resistant tumors and require salvage chemotherapy. In this setting, approximately 50% of patients with recurrent pure seminoma achieve durable CR with conventional or high-dose salvage chemotherapy. Identification of biologic markers to predict clinical outcome and an enhanced understanding of the basic biologic features of seminoma may lead to improvements in the management of this disease.  相似文献   
87.
PURPOSE: The aim of this phase I study was to determine the safety and toxicity profile of gemcitabine administered as an intravesical agent in patients with transitional-cell carcinoma (TCC) of the bladder. PATIENTS AND METHODS: Patients with superficial bladder cancer refractory to intravesical bacillus Calmette-Guérin (BCG) therapy and refusing a cystectomy were considered eligible for the trial. Gemcitabine was given in the bladder for 1 hour twice weekly in 100 mL sodium chloride for a total of six treatments. After a 1-week break, a second course of six treatments over 3 weeks was given, followed by response assessment. Four dose levels were explored: 500 mg, 1,000 mg, 1,500 mg, and 2,000 mg. RESULTS: Eighteen patients completed therapy: three at 500 mg, six at 1,000 mg, three at 1,500 mg, and six at 2,000 mg. No grade 3 or 4 toxicity was observed at 500 mg. At 1,000 mg, three patients developed hematuria and one had a skin reaction resembling grade 3 hand-foot syndrome. Three patients at 1,500 mg had no grade 3 or 4 toxicity. Of six patients at 2,000 mg, one had grade 3 thrombocytopenia and neutropenia without infection. Seven patients had a complete response (negative cytology and posttreatment biopsy), and four patients had a mixed response (negative bladder biopsy but positive cytology). CONCLUSION: Gemcitabine has substantial activity as an intravesical agent in BCG-refractory TCC and warrants further investigation. Therapy given twice weekly was associated with minimal bladder irritation and tolerable myelosuppression. The recommended phase II dose for twice-weekly therapy is 2,000 mg.  相似文献   
88.
Venu KM  Koka R  Garikipati R  Shenava Y  Madhu TS 《Injury》2001,32(5):395-400
We present a retrospective review of 13 patients with periprosthetic femoral fractures treated with the Dall-Miles cable and plate fixation system between 1995 and 1999. Of these, 12 fractures were in relation to hip arthroplasty and one was proximal to the femoral component of a total knee replacement. Mean age at presentation was 77 years (range 66-87) with the male female ratio of 6:7. All patients were followed up until there was evidence of clinical and radiological union. The average follow-up period was 6.5 months (range 2.5-24). We achieved satisfactory results in ten patients with average time to union of 4.4 months. The results were unsatisfactory in three patients who required further revision procedures due to failure of fixation or non-union. Internal fixation of the fracture with the loose femoral component left in-situ led to failure of union in one patient. Varus mal-alignment of the femoral component to the shaft of more than 6 degrees was associated with unsatisfactory outcome in two patients. The Dall-Miles cable and plate system is a useful method of internal fixation for majority of periprosthetic femoral fractures. This method may not be suitable if the femoral component is loose or if it is in varus angulation of more than 6 degrees to the shaft of the femur.  相似文献   
89.
Pleuropulmonary balstema with cystic nephroma is a rare dual pathology of pediatric age group. The etiopathogenesis of this entity is not known, still researches indicate towards a common genetic cause. We report a case of this dual pathology in a one and half year old male. Till now only 5 cases have been reported.  相似文献   
90.
A quinazolinone derivative as a novel non-peptidic CCK-B receptor antagonist designated as Qn-In, was synthesized, characterized by spectroscopic techniques and evaluated for radiopharmaceutical potential. The efficiency of labeling with 99mTc was greater than 98% and the complex was stable for about 7 hours at 37°C in presence of serum. Affinity of Qn-In was determined to be in nanomolar range by competitive binding studies on cancer cell line MDA-MB-468. Bio-distribution of 99mTc labeled Qn-In in mice was examined by intravenous administration and time-activity curves were generated. The ligand showed binding to most of the organs, known to express CCK-B receptor. The lack of uptake in brain may be due to the inability of the complex to cross the blood-brain barrier. Our results show that 99mTc labeled Qn-In ligand provides a new template for further development of non-peptidic ligands for diagnosis and therapy of diseases related with CCK-B receptor.  相似文献   
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