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71.
Introduction We report the results of a prospective clinical study using a new self-expanding nitinol stent (Enterprise) designed for the
treatment of wide-necked intracranial aneurysms.
Methods We treated 31 saccular, wide-necked intracranial aneurysms in 30 patients. Ten aneurysms had recanalized after prior endovascular
treatment without a stent, and 21 aneurysms had not been treated before.
Results Stent deployment was successful in all procedures. Additional coil embolization was performed in all aneurysms. Initial complete
angiographic occlusion was achieved in 6 aneurysms, a neck remnant was left in 18 aneurysms and there were 7 residual aneurysms.
Angiographic follow-up examinations of 30 lesions after 6 months demonstrated 15 complete occlusions, 8 neck remnants and
7 residual aneurysms. One patient refused the 6-month angiographic follow-up. Spontaneous occlusion of the aneurysm had occurred
in 14 patients, and 6 aneurysms showed recanalization. Four of these residual aneurysms were retreated. At the 6-month follow-up,
29 parent arteries were unaffected, whereas two parent vessels demonstrated minor asymptomatic narrowing at the stent site.
Two patients experienced one or more possible or probable device-related serious adverse events during the 6-month follow-up
period. There was no procedural morbidity or mortality at 6 months after the procedure.
Conclusion The reported results demonstrated the safety and feasibility of the Cordis Neurovascular Enterprise stent in the treatment
of wide-necked intracranial aneurysms. Initial clinical and angiographic results are favorable.
Werner Weber and Martin Bendszus contributed equally to this work. 相似文献
72.
73.
Markasz L Kis LL Stuber G Flaberg E Otvos R Eksborg S Skribek H Olah E Szekely L 《Leukemia & lymphoma》2007,48(9):1835-1845
Depending on stage and risk factors, up to 30% of patients with advanced Hodgkin lymphoma (HL) progress or relapse. Patients with pleural effusions have a particularly poor prognosis and this stage of HL is regularly resistant to chemotherapy. All currently available HL cell lines are derived from late stage HL patients. In the present study we measured the sensitivity of these HL lines against the 26 most frequently used cytostatic drugs. We used a novel fluorescent short-term survival assay where the cell was incubated with the drugs for 4 days. The precise number of differentially stained live and dead cells was determined using a custom-built automated laser confocal fluorescent microscope. We found that HL cells, independently of their origin, showed very similar sensitivity patterns for several of the drugs. All HL cell lines were highly sensitive to dactinomycin, paclitaxel and etoposide. Our data suggest that the inclusion of dactinomycin and paclitaxel into chemotherapy protocols against late stage Hodgkin lymphoma with pleural effusion may be justified. 相似文献
74.
In many cases, particularly in retrospective studies, only formalin-fixed and paraffin-embedded (FFPE) tissue samples are
available for molecular studies. DNA recovered from FFPE tissues generally consists of fragmented small target sequences with
chemical alterations. Clonality analysis is not easy on FFPE samples, in fact, it requires even more experience than that
of performed on fresh samples or is more complicated than most genomic PCR amplifications for somatic genes. In our study,
we have performed a multi-parameter PCR evaluation investigating immunoglobulin heavy chain gene (IgH) and T-cell receptor
gamma gene (TCRy) rearrangements on non-purified crude lysates of FFPE samples, in order to establish the significance of
different variables on performance of PCR amplification. The results showed that a slight decrease in the concentration of
primers in combination with a slight increase in MgCl2 andTaq polymerase concentrations, as well as the use diluted crude template and a standard amount of dNTPs can be the modifications
of choice while adjusting IgH and TCRy clonality tests on poor quality DNA FFPE samples. Using our improved protocol, 74%
(17/23) of the tested B-cell lymphomas and 68% (31/46) of the tested T-cell lymphomas demonstrated monoclonal PCR product,
proving the applicability of our optimized method. Our experience may be of help during the optimization process in technically
difficult cases as well as to determine which parameters and how should be changed to minimize false-negative and false-positive
results.
Supported in part by the OTKA Research Fund (T046663 KON) and the Hungarian Academy of Sciences, Bolyai Janos Research Fellowship
(E.B.). 相似文献
75.
We evaluated clinical presentation, cerebrospinal fluid (CSF), and magnetic resonance imaging (MRI) in patients with late-onset multiple sclerosis (LOMS). Fifty-two patients with definitive multiple sclerosis (MS) diagnosed after the age of 50 years were identified between 1991 and 2002. Data pertaining to clinical characteristics, CSF analysis, and cerebral and spinal MRI were compared with those of 52 young-onset MS (YOMS) patients matched for sex and disease duration. Mean age at the time of diagnosis was 57 years in the LOMS group - the oldest patient was 82 - and 29 years in the YOMS group. Motor symptoms were significantly more often present in the LOMS than in patients with YOMS (90 % vs. 67 %, p = 0.014). Visual symptoms, residual signs of optic neuritis, and dysarthria were less frequent for LOMS. Sensory symptoms, ataxia, oculomotor symptoms, cognitive disorder, or fatigue did not differ between both groups. The majority of LOMS patients (83 %) had a primary progressive disease course, whereas 94 % of the YOMS group had a relapsing-remitting course. MRI showed typical multifocal supratentorial (LOMS vs. YOMS: 96 % vs. 98 %) and infratentorial (44 % vs. 62 %) lesions without significant group differences. Of particular interest, spinal lesions were more common (81 %) in LOMS compared to YOMS (48 %, p = 0.024), and cerebellar lesions were less frequent in the LOMS group (11 % vs. 44 %, p = 0.001). Gadolinium-enhanced lesions were initially present in less LOMS patients (15 %) than in YOMS (63 %, p < 0.001). CSF analysis revealed pleocytosis less frequently in LOMS (34 %) compared to YOMS (67 %, p = 0.006) but oligoclonal banding occurred without in both groups without differences. YOMS patients responded to corticosteroids (93 %) to a significantly greater degree than LOMS patients (73 %; p = 0.004). For individuals who develop LOMS, a primary progressive course is frequent, with motor symptoms as the prominent feature. Vigilance is necessary to recognise MS in this population because of its unusual presentation. 相似文献
76.
In anaesthetized adult rats, facial nerve injury causes a disinhibition of the interhemispheric connections between homotopic representation fields in the primary motor cortex with a latency of 4 min (Toldi et al., 1996, Neurosci Lett. 203, 179-182). One possible explanation for the induction of such rapid changes is an alteration of the somatosensory input to the motor cortex. To test this hypothesis, unit activity in primary motor cortex was recorded during electrical stimulation of trigeminal afferents in the contralateral whisker-pad. About one-third of all recorded primary motor cortex neurons responded with latencies shorter than in the ventrolateral and posterior nuclei of the thalamus. Responses failed at stimulation frequencies > or = 10 Hz and after elimination or inactivation of the somatosensory cortex. Within primary motor cortex, the activatable neurons displayed a bilaminar distribution and were identified as pyramidal neurons by neurobiotin labelling. The results suggest that trigeminal afferents participate in modulation of the activity of primary motor cortex output neurons via primary somatosensory cortex-to-primary motor cortex associational connections, even under anaesthesia. 相似文献
77.
Olena Bukalo Emilie Campanac Dax A. Hoffman R. Douglas Fields 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(13):5175-5180
Learning and other cognitive tasks require integrating new experiences into context. In contrast to sensory-evoked synaptic plasticity, comparatively little is known of how synaptic plasticity may be regulated by intrinsic activity in the brain, much of which can involve nonclassical modes of neuronal firing and integration. Coherent high-frequency oscillations of electrical activity in CA1 hippocampal neurons [sharp-wave ripple complexes (SPW-Rs)] functionally couple neurons into transient ensembles. These oscillations occur during slow-wave sleep or at rest. Neurons that participate in SPW-Rs are distinguished from adjacent nonparticipating neurons by firing action potentials that are initiated ectopically in the distal region of axons and propagate antidromically to the cell body. This activity is facilitated by GABAA-mediated depolarization of axons and electrotonic coupling. The possible effects of antidromic firing on synaptic strength are unknown. We find that facilitation of spontaneous SPW-Rs in hippocampal slices by increasing gap-junction coupling or by GABAA-mediated axon depolarization resulted in a reduction of synaptic strength, and electrical stimulation of axons evoked a widespread, long-lasting synaptic depression. Unlike other forms of synaptic plasticity, this synaptic depression is not dependent upon synaptic input or glutamate receptor activation, but rather requires L-type calcium channel activation and functional gap junctions. Synaptic stimulation delivered after antidromic firing, which was otherwise too weak to induce synaptic potentiation, triggered a long-lasting increase in synaptic strength. Rescaling synaptic weights in subsets of neurons firing antidromically during SPW-Rs might contribute to memory consolidation by sharpening specificity of subsequent synaptic input and promoting incorporation of novel information. 相似文献
78.
The echographic appearance of pelvic masses in children was examined in 38 patients. Sonography was correct in determining the site of origin in all cases. Cystic uterine masses and cystic ovarian masses were the most specific, representing hydrometrocolpos and benign ovarian cysts. A nonspecific sonographic pattern was encountered with complex masses, which proved to be ovarian teratomas, hemorrhagic ovarian cysts and pelvic abscesses. Although a number of characteristic features of teratomes have been described, these signs were seen very rarely in children. 相似文献
79.