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81.
BCL2 mutations have been suggested to confer an adverse prognosis to follicular lymphoma (FL) patients, but their prognostic value has not been assessed in patients treated with a rituximab‐containing regimen. Here we evaluated the prognostic value of BCL2 mutations in a large prospective cohort of 252 patients with FL treated with immunochemotherapy in the PRIMA randomized trial. Using a DNA‐targeted sequencing approach, we detected amino acid altering mutations in 135 patients (54%) and showed that these mutations were probably mediated by the over‐activation of AICDA (activation‐induced cytidine deaminase) in the context of the t(14;18) translocation. The BCL2 variants identified in PRIMA patients affected the BH1, BH2, and BH3 functional motifs at a lower frequency than the N‐terminus and flexible loop domain, with mostly conservative aminoacid changes. With a median follow‐up of 6.7 years, we did not observe any impact of BCL2 mutations either on overall survival or progression‐free survival.  相似文献   
82.
A venobronchial fistula developed between the azygous vein and the upper aspect of the right main bronchus 12 months after completion of the treatment of a stage IIIB non-small-cell lung cancer in a 54-year-old man. The fistula contained the tip of the catheter placed for chemotherapy perfusion. The reported case presented risk factors previously identified for such a complication. In addition, some clinical particularities were present, suggesting new potent risk factors and some preventive means for safe long-term central venous catheterization.  相似文献   
83.
Pyrethroid-treated nets are an efficient tool for reducing malaria transmission and morbidity. The recent evolution of pyrethroid resistance in several Anopheles species represents a major threat for the future success of roll back malaria in Africa. The possible use of nonpyrethroid insecticides, such as carbamates, on nets is a promising alternative solution because these insecticides are effective against susceptible and pyrethroid-resistant populations of Anopheles and Culex mosquitoes. Unfortunately, carbamate resistance as a result of insensitive acetylcholinesterase has recently been detected in Anopheles gambiae s.s. populations from C?te d'Ivoire. Using biochemical assays on surviving Anopheles mosquitoes from an experimental hut trial, we showed evidence for selection for an insensitive acetylcholinesterase mechanism by carbamate impregnated bednets. However, no such selection has been found with nets treated with pyrethroid alone or pyrethroid/carbamate "two-in-one" -treated nets. Because pyrethroid-impregnated nets were suspected to select for the Kdr mutation in An. gambiae, we propose that use of two-in-one nets could be a promising alternative strategy for the management of insecticide resistance in malaria vectors.  相似文献   
84.
The aim of this study was to investigate the effects of swimming with a wetsuit on energy expenditure during subsequent cycling. Nine well-trained triathletes underwent three submaximal trials. The first trial (SC) consisted of a 750-m swim realised at a competition pace, followed by a 10-min cycling exercise at a power output corresponding to the ventilatory threshold . The two other trials were composed of the same cycling exercise, preceded either by a 750-m swim with a wetsuit (WSC) or by a cycling warm-up (Ctrl). The main results are that the WSC trial was characterised by significantly lower swimming cadence (-14%), heart rate (-11%), and lactate values (-47%) compared to the SC trial, p < 0.05. Moreover, cycling efficiency was significantly higher in the WSC trial compared to the SC trial (12.1% difference, p < 0.05). The lower relative intensity observed during swimming with a wetsuit suggest the relative importance of swimming condition on the total performance in a sprint triathlon.  相似文献   
85.
Nanocrystalline apatites analogous to bone mineral are very promising materials for the preparation of highly bioactive ceramics due to their unique intrinsic physico-chemical characteristics. Their surface reactivity is indeed linked to the presence of a metastable hydrated layer on the surface of the nanocrystals. Yet the sintering of such apatites by conventional techniques, at high temperature, strongly alters their physico-chemical characteristics and biological properties, which points out the need for “softer” sintering processes limiting such alterations. In the present work a non-conventional technique, spark plasma sintering, was used to consolidate such nanocrystalline apatites at non-conventional, very low temperatures (T < 300 °C) so as to preserve the surface hydrated layer present on the nanocrystals. The bioceramics obtained were then thoroughly characterized by way of complementary techniques. In particular, microstructural, nanostructural and other major physico-chemical features were investigated and commented on. This work adds to the current international concern aiming at improving the capacities of present bioceramics, in view of elaborating a new generation of resorbable and highly bioactive ceramics for bone tissue engineering.  相似文献   
86.
Mechano-gated ion channels play a key physiological role in cardiac, arterial, and skeletal myocytes. For instance, opening of the non-selective stretch-activated cation channels in smooth muscle cells is involved in the pressure-dependent myogenic constriction of resistance arteries. These channels are also implicated in major pathologies, including cardiac hypertrophy or Duchenne muscular dystrophy. Seminal work in prokaryotes and invertebrates highlighted the role of transient receptor potential (TRP) channels in mechanosensory transduction. In mammals, recent findings have shown that the canonical TRPC1 and TRPC6 channels are key players in muscle mechanotransduction. In the present review, we will focus on the functional properties of TRPC1 and TRPC6 channels, on their mechano-gating, regulation by interacting cytoskeletal and scaffolding proteins, physiological role and implication in associated diseases.  相似文献   
87.
New prevention strategies are urgently needed to slow the spread of the HIV/AIDS pandemic, and in the absence of an effective vaccine, there is hope that "microbicides"-HIV inhibitors applied to mucosal surfaces before sexual intercourse-may be able to make an impact. Because developing countries are at the center of the epidemic, affordability and stability during storage are key criteria for candidate microbicides. Furthermore, because formulation strategies that provide long-duration protection after a single dose may enhance acceptability and compliance, stability in the vaginal environment and in the presence of semen should also be considered. PSC-RANTES, a human chemokine analog, has shown promise as a candidate microbicide, but because it contains nonnatural structures that necessitate chemical synthesis steps, it is not suitable for production at a feasible cost and scale for general distribution in developing countries. We have recently developed 2 new fully recombinant chemokine analogs, 5P12-RANTES and 6P4-RANTES, which show equivalent anti-HIV activity to PSC-RANTES. In this study, we tested the stability of these molecules under conditions related to use as microbicides. Our results suggest that stability issues will not present a major obstacle to the further development of these promising molecules as microbicides.  相似文献   
88.

Objective

Bilateral salpingo-oophorectomy (BSO) is the gold standard prophylactic surgery for BRCA1 or 2 mutation carriers. However, due to the resulting early menopause and fertility desires, young women are reluctant to undergo this procedure. In view of the recent literature on ovarian carcinogenesis, we wish to report a novel conceptual surgical procedure we called “radical fimbriectomy.” This procedure is aimed to protect this subset of high-risk women from high-grade serous pelvic carcinoma, while preserving their ovarian function.

Methods

Women with BRCA mutation, who were scheduled for BSO, were informed of the procedure approved by our local review board. Radical fimbriectomy consists of removing all the tube and the fimbrio-ovarian junction, step immediately followed in this developmental phase by completion oophorectomy. Four methods of partial ovarian transsection were prospectively compared: sharp division, stapler, bipolar division and harmonic scalpel. Surgical safety and pathological alterations were assessed. All specimens underwent extensive pathological evaluation using both SEE-FIM protocol and serial sections.

Results

Fourteen women were enrolled in the study. Sharp and EndoGIA® appeared to be the safest methods of ovarian resection providing the best specimen quality for pathological examination.

Conclusion

We believe this technique could be suggested to young mutation carriers reluctant to undergo BSO. This approach is preferable to no prophylactic surgery at all. However, until the safety and validity of this procedure is confirmed by a multi-institutional study, women who undergo radical fimbriectomy should continue to receive regular multimodal evaluation and be advised of the risks involved until they finally accept secondary castration.  相似文献   
89.
The aim of these recommendations of the French National College of Gynaecologists and Obstetricians was to focus the surgeon's attention on those aspects which could allow him/her to prevent, or at least limit, the incidence of these serious complications, in the absence of a previous laparotomy or specific risk factors (obesity, gauntness, large pelvic mass or pregnancy), four widely evaluated techniques can be used in a first line approach (Grade B): blind trans-umbilical technique following creation of pneumoperitoneum with a needle, open laparoscopy (Hasson technique), left upper quadrant entry (pneumoperitoneum and insertion of the first trocar) and direct trans-umbilical trocar with no prior pneumoperitoneum. The currently existing trials do not allow one or another of these techniques to be preferred. Radially expanding insertion systems and optical trocars cannot be recommended as a first-line approach, as a consequence of their currently insufficient degree of evaluation (Grade C). Trans-umbilical (blind or open) laparoscopic entry in a slim woman must be associated with care, as a result of the proximity of the large vessels (Grade B). If a blind trans-umbilical insertion technique is decided upon, one option can be to insufflate into the left upper quadrant (professional consensus). In the case of a previous midline laparotomy, whatever the technique used, initial entry is recommended at a distance from the scars (Grade B). It is recommended to carry out micro-laparoscopy in the LUQ, because this is the most completely evaluated technique for this indication (Grade C). One option is to use open laparoscopy at a distance from the existing scars (professional consensus). During pregnancy, the insertion position of the first laparoscopic trocar will need to be adapted according to the volume of the uterus (Grade B). Starting from 14 WG, trans-umbilical Veress needle insufflation is contraindicated (Grade C). Two trocar insertion techniques are thus recommended: open laparoscopy (using the trans-umbilical or supra-umbilical routes, depending on the volume of the uterus) or micro-laparoscopy via the left upper quadrant (Grade C). After the second quarter of pregnancy, with laparoscopy the patient will need to be placed on a table inclined towards her left side, in order to minimize compression of the inferior vena cava (Grade B). In the case of laparoscopy during pregnancy, the insufflation pressure must be maintained at a maximum of 12 mm Hg (Grade B). After 24 WG, if laparoscopy is performed, it is recommended to apply open laparoscopy, above the level of the umbilicus (professional consensus). Patients must be informed of the risks inherent to the insertion of trocars during laparoscopy (vascular, bowel or bladder injury) (Grade B). The more benign the pathology requiring an operation, the more detailed the supplied information must be, including that concerning rare but serious complications (Grade B).  相似文献   
90.
Interictal or ictal events in partial epilepsies may project on scalp EEG contralaterally to the side of the epileptogenic lesion. Such paradoxical lateralization can be observed in case of para-sagittal generators, and is likely due to the spatial orientation of the generator, presenting an oblique projection towards the midline. We present here a case of medial occipital epilepsy investigated using EEG, MEG and stereoelectroencephalography (SEEG). MRI displayed a focal cortical dysplasia in the superior margin of the right calcarine fissure. SEEG demonstrated bilateral medial occipital interictal spikes, with an inversion of polarity at the level of the lesion and a contralateral propagation occurring in 10 ms. Interictal iterative EEG cartographies showed a large posterior field, with a maximum contralateral to the initial generator (EEG paradoxical lateralization). With the same number of channels, interictal iterative MEG cartographies were more precise and more complex than EEG ones, indicating an onset accurately lateralized. A few milliseconds later, MEG cartographies were quadripolar, thus indicating two homotopic active generators. These MEG and EEG cartographies have been reproduced using BESA dipole simulator. Relative merits of MEG and EEG are still debated. With 151 channels, MEG source localizations indicated the right medial occipital area, as demonstrated by SEEG. An investigation with a corresponding number of EEG channels was not performed. After a down sampling to 64 sensors, this precision was lost. MEG and EEG source localization results, both with 64 channels, were quite comparable, indicating both medial occipital areas. However, a careful analysis of MEG/EEG iterative cartographies, performed with the same number of channels in both modalities, demonstrated that, in this configuration, MEG sensitivity was superior to the EEG one, allowing separating two medial occipital sources, characterized in SEEG by a time delay of 10 ms.  相似文献   
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