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41.
Chitosan fibers blended with polyethylene oxide (CHIT_PEO) and crosslinked with genipin were fabricated by electrospinning technique. Subsequently, CHIT_PEO bioactive glass composite electrospun mats were fabricated with the aim to achieve flexible structures with adequate mechanical properties and improved biological performance respect to CHIT_PEO fibers, for potential applications in wound healing. Three different compositions of bioactive glasses (BG) were selected and investigated: 45S5 BG, a Sr and Mg containing bioactive glass (BGMS10) and a Zn-containing bioactive glass (BGMS_2Zn). Particulate BGs (particles size < 20 μm) were separately added to the starting CHIT_PEO solution before electrospinning. The two recently developed bioactive glasses (BGMS10 and BGMS_2Zn) showed very promising biological properties in terms of bioactivity and cellular viability; thus, such compositions were added for the first time to CHIT_PEO solution to fabricate composite electrospun mats. The incorporation of bioactive glass particles and their distribution into CHIT_PEO fibers were assessed by SEM and FTIR analyses. Furthermore, CHIT_PEO composite electrospun mats showed improved mechanical properties in terms of Young’s Modulus compared to neat CHIT_PEO fibers; on the contrary, the values of tensile strain at break (%) were comparable. Biological performance in terms of cellular viability was investigated by means of WST-8 assay and CHIT_PEO composite electrospun mats showed cytocompatibility and the desired cellular viability.  相似文献   
42.
43.

Objective

Neuroticism and impulsivity are the personality variables most consistently associated with drug-dependent patients. To date, no data mining procedures have been applied to explore the differential role of personality variables in this population.

Methods

The personality profile of 336 drug-dependent patients was compared with that of a sample of community participants in the context of a decision tree learning approach using the Alternative Five Factor Model. The resulting discriminant model was cross-validated.

Results

Neuroticism and impulsivity were the most relevant variables in the resulting model, but their association appeared to be hierarchically organized. In the personality characterization of these patients, neuroticism became the main discriminant dimension, whereas impulsivity played a differential role, explained by means of an interaction effect. Decision tree learning models appear to be a heuristic theoretical and empirical approximation to the study of relevant variables, such as personality traits, in drug-dependency research.  相似文献   
44.

Background

Cyclin D1-positive B cells are occasionally found in the mantle zones of reactive lymphoid follicles, a condition that has been called “in situ mantle cell lymphoma”. The clinical significance of this lesion remains uncertain.

Design and Methods

The clinical and pathological characteristics, including SOX11 expression, of 23 cases initially diagnosed as in situ mantle cell lymphoma were studied.

Results

Seventeen of the 23 cases fulfilled the criteria for in situ mantle cell lymphoma. In most cases, the lesions were incidental findings in reactive lymph nodes. The t(11;14) was detected in all eight cases examined. SOX11 was positive in seven of 16 cases (44%). Five cases were associated with other small B-cell lymphomas. In two cases, both SOX11-positive, the in situ mantle cell lymphoma lesions were discovered after the diagnosis of overt lymphoma; one 4 years earlier, and one 3 years later. Twelve of the remaining 15 patients had a follow-up of at least 1 year (median 2 years; range, 1–19.5), of whom 11 showed no evidence of progression, including seven who were not treated. Only one of 12 patients with an in situ mantle cell lymphoma lesion and no diagnosis of mantle cell lymphoma at the time developed an overt lymphoma, 4 years later; this case was also SOX11-positive. The six remaining cases were diagnosed as mantle cell lymphoma with a mantle zone pattern. Five were SOX11-positive and four of them were associated with lymphoma without a mantle zone pattern.

Conclusions

In situ mantle cell lymphoma lesions are usually an incidental finding with a very indolent behavior. These cases must be distinguished from mantle cell lymphoma with a mantle zone pattern and overt mantle cell lymphoma because they may not require therapeutic intervention.  相似文献   
45.
Background: Oral exfoliative cytology is a diagnostic method that involves the study of cells exfoliated from the oral mucosa. Ions/particles released from metallic implants can remain in the peri‐implant milieu. The aim of the present study is to assess the presence of metal particles in cells exfoliated from peri‐implant oral mucosa around titanium dental implants. Methods: The study comprised 30 patients carrying titanium dental implants, who had neither a metallic prosthesis nor metal restorations in neighboring teeth. Individuals undergoing orthodontic therapy and those who had oral piercing were also excluded from the study. The study sample included patients with and without peri‐implantitis. Cytologic samples of the peri‐implant area were collected. Samples of the marginal gingiva on the contralateral side of the implant were taken from the same individuals to serve as control. Cytologic analysis was performed using light microscopy. Titanium concentration was determined using inductively coupled plasma‐mass spectrophotometry. Results: Metal‐like particles were observed inside and outside epithelial cells and macrophages in cytologic smears of peri‐implant mucosa of both patients with and without peri‐implantitis. No particles were found in the control cytologic samples. The concentration of titanium was higher in the peri‐implantitis group compared with the group without peri‐implantitis; no traces of titanium were observed in controls. Conclusions: Regardless of an inflammatory response, ions/particles are released from the surface of the implant into the biologic milieu. Exfoliative cytology is a simple technique that may be used to detect metal particles in cells exfoliated from the peri‐implant mucosa.  相似文献   
46.
47.
JAK2V617F-negative essential thrombocythemia (ET) is a heterogeneous disease including clonal cases and others without evidence of clonality. However, it is unknown if the detection of myeloid clonality in JAK2V617F-negative ET patients confers a different clinical outcome than those in whom clonal hematopoiesis cannot be demonstrated. The objective of the present study was to evaluate the clinical significance of clonality assessment in patients with JAK2V617F-negative ET. Clonality investigation including mutational status of MPL, TET2, and ASXL1 genes and human androgen receptor (HUMARA) assay was performed in 73 JAK2V617F-negative cases out of 186 subjects consecutively diagnosed with ET in a single institution, at diagnosis or during follow-up. Mutations in MPL, TET2, and ASXL1 were observed in 7, 4, and 2 cases, respectively, whereas clonality by HUMARA assay was demonstrated in 21 out of 46 (46?%) female patients. With a median follow-up of 8?years, death, thrombosis, bleeding, and disease transformation were registered in 7, 10, 8, and 6 patients, respectively. No differences in thrombosis, bleeding or survival were observed according to clonality assessment. The probability of disease transformation at 10?years was higher in patients showing clonal hematopoiesis by presenting mutations in either MPL, TET2, or ASXL1 (64 versus 2?% in patients without mutations, p?相似文献   
48.
49.

Background

It has been suggested that selective sentinel node (SN) biopsy alone can be used to manage early breast cancer, but definite evidence to support this notion is lacking. The aim of this study was to investigate whether refraining from completion axillary lymph node dissection (ALND) suffices to produce the same prognostic information and disease control as proceeding with completion ALND in early breast cancer patients showing micrometastasis at SN biopsy.

Methods

This prospective, randomized clinical trial included patients with newly diagnosed early-stage breast cancer (T < 3.5 cm, clinical N0, M0) who underwent surgical excision as primary treatment. All had micrometastatic SN. Patients were randomly assigned to one of the two study arms: complete ALND (control arm) or clinical follow-up (experimental arm). Median follow-up was 5 years, recurrence was assessed, and the primary end point was disease-free survival.

Results

From a total sample of 247 patients, 14 withdrew, leaving 112 in the control arm and 121 in the experimental arm. In 15 control subjects (13 %), completion ALND was positive, with a low tumor burden. Four patients experienced disease recurrence: 1 (1 %) of 108 control subjects and 3 (2.5 %) of 119 experimental patients. There were no differences in disease-free survival (p = 0.325) between arms and no cancer-related deaths.

Conclusions

Our results strongly suggest that in early breast cancer patients with SN micrometastasis, selective SN lymphadenectomy suffices to control locoregional and distant disease, with no significant effects on survival.  相似文献   
50.
To present a case of laparoscopic robotic-assisted simple prostatectomy with temporary clamping of the bilateral hypogastric arteries. A 74-year-old patient with large prostatic adenoma (> 80 ml) underwent robotic-assisted laparoscopic transvesical adenoma enucleation according to Sotelo’s technique. The hypogastric arteries were isolated just below the ureteral cross with the iliac vessels and bilaterally occluded for 12 minutes during enucleation of the adenoma. The patient’s pain was mild after surgery and he required short-term analgesics and antibiotic prophylaxis. Blood loss was 80 ml. The transient occlusion of the internal iliac arteries is a proven maneuver to reduce bleeding during pelvic surgery. We propose the temporary clamping of the bilateral internal iliac arteries as a safe and rapid surgical maneuver to reduce the intraoperative risk of bleeding, especially when performing first procedures.  相似文献   
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