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101.
Mononuclear ruthenium-dmso compounds showed interesting antimetastatic properties on experimental models of solid tumours. In line with the interesting results with multinuclear platinum complexes, which proved to overcome cisplatin resistance, we thought it worthwhile to test the pharmacological properties of some dinuclear ruthenium complexes to ascertain the possible advantages due to the introduction of a second metal centre over NAMI-A and its mononuclear analogues. These compounds belong to the general formula X2[[RuCl4(dmso-S)]2(mu-L)] or [X][[RuCl4(dmso-S)](mu-L)[RuCl3(dmso-S)(dmso-O)]] where L is a nitrogen donor ligand (pyrazine; pyrimidine; 4,4'-bipyridine; 1,2-bis(4-pyridyl)ethane; 1,2-bis(4-pyridyl) ethylene; 1,3-bis(4-pyridyl)propane) and X a counterion. We focused on parameters related to metastatic ability such as gelatinase activity, detected by zymography, and invasive potential, measured by means of a transwell chamber. These activities were correlated to the ability to inhibit tumour metastases in vivo. All dinuclear complexes, except compound D8 ([NH4]2[[RuCl4(dmso-S)]2(mu-pyz]), decrease the number of tumour cells that cross a matrigel barrier, and inhibit MMP-9 gelatinolytic activity at concentrations lower than that of NAMI-A and of other mononuclear ruthenium complexes. In vivo compounds D5 (Na2[[RuCl4(dmso-S)]2(mu-ethylbipy)]) and D7 ([NH4][[RuCl4(dmso-S)](mu-pyz)[RuCl3(dmso-S) (dmso-O)]]) show anti-metastasis activity, at two dose levels, with mild or null effect on primary tumour growth; compound D8 is the weakest active. All compounds tend to accumulate in liver and kidneys, rather than in tumour and lungs. However, compound D5, the most active in vitro on invasion and gelatinases and active in vivo on metastasis, is better concentrated in the lungs than compound D8 which is less active or inactive in vitro and in vivo. Histological analysis show liver, as well as kidney toxicities that limit in vivo activity. These data thus suggest dinuclear ruthenium complexes as promising anti-invasive agents for cancer treatment.  相似文献   
102.
OBJECTIVE: Mutations of the rhodopsin gene are responsible for autosomal dominant or recessive retinitis pigmentosa (RP). The present study reports the first prenatal diagnosis performed on chorionic villi biopsy of a pregnant woman affected by a severe form of autosomal dominant transmitted RP, due to the Arg135Trp substitution. METHODS: The rhodopsin gene was analysed by automated direct sequencing and, for the first time, by fluorescence-assisted mismatch analysis (FAMA). The latter is an inexpensive, rapid and particularly sensitive method, based on the chemical cleavage of the mismatch in heteroduplex DNA molecules marked with strand-specific fluorophores. RESULTS: FAMA is a feasible procedure for prenatal molecular diagnosis of rhodopsin mutations. The redundancy of signals obtained by FAMA and its sensitivity make it suitable for identifying exactly the position of the mutation and the nucleotide substitution. CONCLUSIONS: An association is proposed between FAMA and automated direct sequencing procedures, in order to achieve optimal results in terms of reliability for prenatal diagnosis of rhodopsin mutations.  相似文献   
103.
OBJECTIVE: To evaluate whether the association of antioxidants and anti-inflammatory compounds may be beneficial in treatment of patients with abacterial prostatovesiculoepididymitis (PVE) and elevated seminal leukocyte concentrations. DESIGN: Open, prospective, random study. SETTING: Academic research environment. PATIENT(S): Ninety-eight patients with PVE who had increased seminal leukocyte concentrations (>1 x 10(6) cells/mL).Carnitines (group A; n = 30) or nonsteroidal anti-inflammatory drugs (group B; n = 16) for 4 months; nonsteroidal anti-inflammatory drugs for 2 months, followed by treatment with carnitines for 2 months (group C; n = 26); or nonsteroidal anti-inflammatory treatment given concomitantly with carnitines (group D; n = 26) for 4 months. MAIN OUTCOME MEASURE(S): Semen variables, production of reactive oxygen species, and pregnancy outcome were evaluated before and after treatment and following a 3-month washout period. RESULT(S): Patients in group C had the highest reduction in production of reactive oxygen species associated with increased sperm motility and viability. Groups B and D experienced intermediate effects, and group A experienced the least effect. CONCLUSION(S): Antioxidant treatment with carnitines is effective in patients with abacterial PVE and increased seminal leukocyte concentrations if these patients have been pretreated with nonsteroidal anti-inflammatory drugs.  相似文献   
104.
Cancer-testis antigens expressed by different-histotype transformed cells are suitable targets for tumor immunotherapy. However, their heterogeneous expression in neoplastic lesions limits the eligibility of patients for cancer-testis antigen-directed vaccination, and low levels of cancer-testis antigens' expression may impair immune recognition of malignant cells. Because of the primary clinical relevance of cancer-testis antigens' expression in neoplastic tissues, 68 unrelated or sequential metastatic lesions from 56 patients were used to characterize the molecular mechanisms regulating the presence and levels of expression of different cancer-testis antigens of the MAGE family (i.e., MAGE2, 3 and 4) in cutaneous melanoma. Polymerase chain reaction-based methylation analyses showed that methylation status of specific cytosine-guanine dinucleotides in the promoters of investigated cancer-testis antigens correlated with their heterogeneous expression within unrelated metastatic melanoma lesions, and with their homogeneous expression among sequential metastases from three patients with melanoma. Unlike methylated promoters, unmethylated promoters of MAGE2, 3 and 4 genes drove the expression of reporter gene-enhanced green fluorescent protein after transient transfection of cancer-testis antigen-positive Mel 142 melanoma cells. Furthermore, de novo expression of MAGE3 gene induced by the treatment of Mel 195 melanoma cells with the DNA hypomethylating agent 5-aza-2'-deoxycytidine was associated with a 6%-12% demethylation of selected cytosine-guanine dinucleotides in its promoter. Finally, 5-aza-2'-deoxycytidine induced a 16-fold increase of MAGE3 expression in Mel 313 melanoma cells expressing constitutively low levels of the antigen, but did not affect that of Mel 275 melanoma cells expressing high baseline levels of MAGE3. Overall, these findings identify promoter methylation as a shared mechanism directly regulating the expression of therapeutic cancer-testis antigens in metastatic melanomas, and foresee the clinical use of 5-aza-2'-deoxycytidine to design new chemoimmunotherapeutic strategies in patients with melanoma.  相似文献   
105.
106.
OBJECTIVE: Some controversy exists as to whether polytetrafluoroethylene (PTFE) is equivalent to reversed saphenous vein (SV) as bypass graft material for above-knee femoropopliteal revascularization. We compared the 5-year patency rate with reversed SV and PTFE grafts in patients with claudication who underwent bilateral above-knee femoropopliteal revascularization. METHODS: Between January 1994 and December 1997, 51 patients (102 limbs) with bilateral disabling claudication due to superficial femoral artery occlusion underwent above-knee femoropopliteal bypass grafting, with SV in one limb and PTFE graft in the other limb. Patients were randomly selected for sequential surgical treatment with either SV-PTFE or PTFE-SV. Kaplan-Meier analysis was used to estimate patency rate, and various factors were analyzed to ascertain any association with revascularization failure. RESULTS: There was no perioperative (30 day) limb loss or death, but five late deaths (late survival rate, 90%). Mean follow-up was 59 months. In the SV group, three bypass grafts failed, requiring repeat operation in only one patient. In the PTFE group, eight bypass grafts failed, leading to five repeat operations. There was no statistically significant difference in primary "assisted" patency rate for the two grafts: 100%, 98%, and 94% for SV grafts, and 96%, 84%, and 84% for PTFE grafts (P =.09), after 1, 3, and 5 years, respectively. CONCLUSIONS: The overall results of this randomized study show that SV and PTFE grafts have a statistically comparable patency rate when used above the knee in patients with claudication. Use of SV, however, leads to fewer occlusions and repeat operations.  相似文献   
107.
This article reconstructs how workers perceived asbestos hazards, using narratives from a group of migrant workers at the crocidolite mine of Wittenoom Gorge, Western Australia. The mine employed about 7000 workers over the entire period of its operation from 1943 to 1966-relying heavily on migrant workers. The exposure to asbestos dust caused a huge number of occupational respiratory diseases in workers, leading Wittenoom later to be labelled as a modern industrial disaster.Fieldwork involved 137 interviews with Italians who had worked at Wittenoom. They constituted 18% of the mine's work-force and were employed as miners or millers between 1951 and 1966. We interviewed workers who had returned to Italy, relatives of Italian workers now deceased, and workers who had settled in Australia. The results confirm the seriousness of the occupational exposure to asbestos and the weaknesses of the health surveillance program. Although workers were given no health-related information, they felt they were at risk and left the job as soon as possible.From the early 1950s onward, some of the workers became aware of a long-term connection between work at Wittenoom and lung illnesses that required hospitalisation and caused deaths. However, up to the early 1960s, workers at the mine were led to believe that the respiratory disease spreading among them was tuberculosis.  相似文献   
108.
AIMS AND BACKGROUND: Emergency surgery for colorectal cancer is associated with a higher postoperative morbidity and mortality rate and a poor long-term outcome compared with elective surgery. The aim of the present study was to compare early and late outcome after elective and emergency surgery for malignant colorectal cancer, looking for the principal determinants of a worse outcome after emergency colorectal surgery. METHODS: A retrospective study of 236 patients presenting with colorectal cancer over an 8-year period was undertaken. Of these, 118 presented as emergencies, whereas 118 patients, well matched for age, sex, site of tumor and TNM admitted as elective, were included in the study. Data reviewed included postoperative mortality and morbidity and long-term outcome. RESULTS: The 30-day operative mortality rate was significantly higher in the emergency group than in the electively treated group (11.9% versus 3.4%, P < 0.01). The higher mortality rate was observed in the perforation group. The 30-day operative morbidity was higher in the emergency group (27.1% versus 12.7%, P < 0.05). Anastomotic failure was a serious complication: following primary resection, we observed 4 non-fatal (5.4%) and two fatal (2.7%) anastomotic leaks after 74 primary anastomoses. Among emergency-treated patients, the procedures characterized by the highest percentage of postoperative complications were three-stage resections (63.6%). The 5-year survival rate was greater after elective surgery (59% versus 39%). CONCLUSIONS: The early and long-term outcome following emergency colorectal surgery was significantly lower than that after elective surgery. Although medical complications in patients with end-stage cancer played an important role, surgical failures still had an important impact on outcome.  相似文献   
109.
BACKGROUND: The objective of the current study was to evaluate in a multicenter setting the feasibility and efficacy of a high-dose sequential (HDS) chemotherapy regimen that combined intensive debulking and high-dose therapy (HDT) with peripheral blood progenitor cell (PBPC) autografting in patients with refractory or recurrent Hodgkin lymphoma (HL). METHODS: Data were collected from 102 patients with HL who were treated with the HDS regimen at 14 centers associated with the Intergruppo Italiano Linfomi. Twenty-four patients had primary refractory HL, 59 patients had their first recurrence of HL (within 1 year in 32 patients and > 1 year in 27 patients), and 19 patients had multiple disease recurrences. The HDS regimen included the sequential delivery of high-dose (hd) cyclophosphamide with PBPC harvesting, methotrexate, etoposide, then HDT (usually hd mitoxantrone plus L-phenylalanine mustard) with PBPC autografting. In addition, radiotherapy was delivered to 36 patients at sites of bulky or persistent disease. RESULTS: Ninety-two patients (90%) completed the HDS program. There were five toxic deaths (treatment-related mortality rate, 4.9%) and six secondary malignan cies (five patients developed myelodysplastic syndrome/acute myelogenous leukemia, and one patient developed colorectal carcinoma). At a median follow-up of 5 years, the 5-year overall survival (OS) and event-free survival (EFS) projections were 64% (95% confidence interval [95% CI], 54-74%) and 53% (95% CI, 43-63%), respectively. Patients with their first recurrence had the most favorable outcome, with 5-year OS and EFS projections of 77% (95% CI, 66-88%) and 63% (95% CI, 50-76%), respectively. There were no significant differences between patients with early first recurrence and late first recurrence. The poorest outcome was observed in patients with refractory HL, with 5-year OS and EFS projections of 36% (95% CI, 16-55%) and 33% (95% CI, 14-52%), respectively. Patients who received HDS chemotherapy after multiple recurrences had an intermediate outcome. Multivariate analysis showed that refractory disease and systemic symptoms at the time of initial presentation were associated significantly associated with poor OS and EFS. CONCLUSIONS: The use of HDS chemotherapy for patients with refractory and/or recurrent HL is feasible at the multicenter level. The combination of intensive debulking and HDT with PBPC autografting offers a good chance of prolonged disease free survival for patients with their first recurrence of HL.  相似文献   
110.
The massive accumulation of gelatinous material at and below the seawater surface occurred in Northern Adriatic, at a frequency and with such an extension to cause serious environmental and economic damages. The present review describes the updated knowledge and considers the main hypotheses on mucilage formation. They focus, in turn, on organisms that produce mucilage, on the particular hydrodynamic of the North Adriatic basin, on the role of nutrients, but the trigger mechanism has not yet been really understood. Finally, the theoretical framework recently proposed by Azam et al. is presented. In the organic matter continuum view, organisms of the microbial loop just represent a part of the whole picture from which specific mechanisms of interactions are examined and few important pathways are outlined for future research.  相似文献   
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