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Coprological examination of 40 Apodemus mystacinus Danford and Alston 1877 from Jordan revealed oocysts of three species of genus Eimeria. Two species are described as new. Eimeria zuhairamri sp. n. has broadly ellipsoidal oocysts 29.6 (27.0–34.0)×23.3 (22.0–25.0) m with distinctly granulated wall and oocyst residuum. Endogenous development occurs in jejunum and ileum. Eimeria alorani sp. n. has oocysts 26.9 (23.0–29.0)×19.3 (18.0–22.0) m with smooth wall and absent residuum. Endogenous development is confined to the caecum. The third species, developing in jejunum, has oocysts morphologically indistinguishable from Eimeria uptoni. The identity of E. uptoni and the taxonomy of Eimeria of Apodemus are discussed.  相似文献   
3.
The thermal dehydrochlorination of poly(vinyl chloride) (PVC) in an inert atmosphere was investigated by the continuous potentiometric method. The effect of the structure of alicyclic and aliphatic α,β-unsaturated ketones on the rate of dehydrochlorination was examined, and a new mechanism of initiation for the dehydrochlorination of PVC was suggested. The results obtained demonstrate that the basic cause of the thermal instability of PVC are structures of the type of cisoid α,β-unsaturated ketone, dienone, or polyenone which by the dehydrochlorination of regular structural PVC units form isolated double bonds which, in turn, initiate the chain dehydrochlorination of PVC by allyl activation.  相似文献   
4.
Patient's age belongs to the independent prognostic factors of patients after out-of-hospital cardiac arrest (OHCA). This study aimed to evaluate the influence of age on 5-year survival in professionally cardio-pulmonary resuscitated patients with “primary cardiac” etiology OHCA. In this analysis of prospective multi-centric study, from April 1, 2002 until August 31, 2004, a total of 560 patients were included (aged 16-97 years) from the East Bohemian region, for whom a professional cardio-pulmonary resuscitation for OHCA was attempted. In the age subgroup <70 years there were 307 patients and in the age subgroup ≥70 years there were 253 patients. Of the subgroup <70 years, 29 patients (10%) survived to year 5 (58% from the 50 patients surviving to day 30), and in the subgroup ≥70 years, we had 4 patients surviving to year 5 (2%) (29% from the 14 patients surviving to day 30), respectively (Fisher‘s exact test; comparison in the all resuscitated patients: p < 0.001, in the population surviving to day 30: p = 0.071). In conclusion, there was a trend towards a worse outcome in 5-year survival following OHCA in the patients aged ≥70 years. Nevertheless, these data support that prognosis OHCA of elders is not associated with universal dismal outcome.  相似文献   
5.
A hippocampal‐prominent event‐related potential (ERP) with a peak latency at around 450 ms is consistently observed as a correlate of hippocampal activity during various cognitive tasks. Some intracranial EEG studies demonstrated that the amplitude of this hippocampal potential was greater in response to stimuli requiring an overt motor response, in comparison with stimuli for which no motor response is required. These findings could indicate that hippocampal‐evoked activity is related to movement execution as well as stimulus evaluation and associated memory processes. The aim of the present study was to investigate the temporal relationship between the hippocampal negative potential latency and motor responses. We analyzed ERPs recorded with 22 depth electrodes implanted into the hippocampi of 11 epileptic patients. Subjects were instructed to press a button after the presentation of a tone. All investigated hippocampi generated a prominent negative ERP peaking at ~420 ms. In 16 from 22 cases, we found that the ERP latency did not correlate with the reaction time; in different subjects, this potential could either precede or follow the motor response. Our results indicate that the hippocampal negative ERP occurs independently of motor execution. We suggest that hippocampal‐evoked activity, recorded in a simple sensorimotor task, is related to the evaluation of stimulus meaning within the context of situation. © 2013 Wiley Periodicals, Inc.  相似文献   
6.
In plants, endocytosis is essential for many developmental and physiological processes, including regulation of growth and development, hormone perception, nutrient uptake, and defense against pathogens. Our toolbox to modulate this process is, however, rather limited. Here, we report a conditional tool to impair endocytosis. We generated a partially functional TPLATE allele by substituting the most conserved domain of the TPLATE subunit of the endocytic TPLATE complex (TPC). This substitution destabilizes TPC and dampens the efficiency of endocytosis. Short-term heat treatment increases TPC destabilization and reversibly delocalizes TPLATE from the plasma membrane to aggregates in the cytoplasm. This blocks FM uptake and causes accumulation of various known endocytic cargoes at the plasma membrane. Short-term heat treatment therefore transforms the partially functional TPLATE allele into an effective conditional tool to impair endocytosis. Next to their role in endocytosis, several TPC subunits are also implicated in actin-regulated autophagosomal degradation. Inactivating TPC via the WDX mutation, however, does not impair autophagy, thus enabling specific and reversible modulation of endocytosis in planta.

Endocytosis is an evolutionarily conserved eukaryotic pathway by which extracellular material and plasma membrane (PM) components are internalized via vesicles (1, 2). Clathrin-mediated endocytosis (CME), relying on the scaffolding protein clathrin, is the most prominent and the most studied endocytic pathway (35). As clathrin does not interact directly with the PM, nor does it recognize cargoes, adaptor proteins are required to act as essential links between the clathrin coat and the PM (6). In plant cells, material selected for CME is recognized by two adaptor complexes, the adaptor complex 2 (AP-2) and the TPLATE complex (TPC) (79). In contrast to TPC, single subunit mutants of AP-2 are viable (7, 8, 1013) and AP-2 recruitment and dynamics appear to rely on TPC function (8, 14).TPC represents an ancestral adaptor complex, which is however absent in present-day metazoans and yeasts. It was experimentally identified as an octameric complex in Arabidopsis and as a hexametric complex in Dictyostelium (8, 15). Plants, however, are the only eukaryotic supergroup identified so far where TPC is essential for life (8, 15), as knockout or severe knockdown of single subunits of TPC in Arabidopsis leads to pollen or seedling lethality, respectively (8, 13). Two TPC subunits, AtEH1/Pan1 and AtEH2/Pan1, were not associated with the other TPC core components when the complex was forced into the cytoplasm by truncating the TML subunit and did not copurify with the other TSET components in Dictyostelium. This indicates that they may be auxiliary components to the core TPC (8, 15). These AtEH/Pan1 proteins were recently identified as important players in actin-regulated autophagy in plants. AtEH/Pan1 proteins recruit several components of the endocytic machinery to the autophagosomes, and are degraded together with them under stress conditions (16). However, whether this pathway serves to degrade specific cargoes or to regulate the endocytic machinery itself (17), and whether the whole TPC is required for this degradation pathway, remains unclear.Genetic and chemical tools to manipulate endocytosis have been extensively investigated via interfering with the functions of endocytic players, such as clathrin (1822), adaptor proteins (7, 1012, 14, 2325), and dynamin-related proteins (2630). The chemical inhibitors originally used to affect CME in plants have recently been described to possess undesirable side effects (31) or to affect proteins that are not only specific for endocytosis: for example, clathrin itself, as it is also involved in TGN trafficking (19, 22). The same is true for several genetic tools currently available to affect CME in plants (18, 21, 22, 30). Manipulation of TPC, functioning exclusively at the PM, represents a very good candidate to affect CME more specifically. So far however, there are no chemical tools to target TPC functions or dominant-negative mutants available. Inducible silencing works, but causes seedling lethality and takes several days to become effective (8). The only tools to manipulate TPC function in viable plants consist of knock-down mutants with very mild reduction of expression and consequently similar mild effects on CME (8, 14, 16, 32).  相似文献   
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8.
The in vitro and in vivo activity of a deoxycytidine analogue, troxacitabine, alone or in combination with imatinib mesylate (IM), was evaluated against human chronic myeloid leukaemia (CML) cell lines both sensitive (KBM5 and KBM7) and resistant (KBM5-R and KBM7-R) to IM. These cell lines differ in their sensitivity to IM but all showed similar sensitivity to treatment with troxacitabine (IC50 = 0.5-1 micromol/l). Combined treatment with troxacitabine and IM revealed additive or synergistic effects. Greater apoptotic response was seen with combined treatment than with either agent alone in KBM7-R cells. In clonogenic assays, troxacitabine showed activity against mononuclear cells from CML patients (IC50 = 0.01 micromol/l) with either IM-sensitive or resistant disease. In vivo efficacy studies were carried out in severe combined immunodeficient mice bearing KBM5 or KBM5-R cells. Troxacitabine was administered i.p. daily for 5 d starting on day 20, at doses of 5, 10, 20, or 25 mg/kg. IM was administered i.p. twice a day for 10 d at a dose of 50 mg/kg starting on day 25. In this setting of late stage disease, troxacitabine led to a significant increase in life span, while IM did not. When IM was combined with troxacitabine at 10 and 25 mg/kg in the KBM5 xenograft model, a further increase in life span was observed and some mice achieved long-term survival. These data indicate that the combination of troxacitabine and IM has significant preclinical activity in advanced CML and that clinical evaluation of this combination is warranted.  相似文献   
9.
Recent findings suggest that neural complexity reflecting a number of independent processes in the brain may characterize typical changes during epileptic seizures and may enable to describe preictal dynamics. With respect to previously reported findings suggesting specific changes in neural complexity during preictal period, we have used measure of pointwise correlation dimension (PD2) as a sensitive indicator of nonstationary changes in complexity of the electroencephalogram (EEG) signal. Although this measure of complexity in epileptic patients was previously reported by Feucht et al (Applications of correlation dimension and pointwise dimension for non-linear topographical analysis of focal onset seizures. Med Biol Comput. 1999;37:208–217), it was not used to study changes in preictal dynamics. With this aim to study preictal changes of EEG complexity, we have examined signals from 11 multicontact depth (intracerebral) EEG electrodes located in 108 cortical and subcortical brain sites, and from 3 scalp EEG electrodes in a patient with intractable epilepsy, who underwent preoperative evaluation before epilepsy surgery. From those 108 EEG contacts, records related to 44 electrode contacts implanted into lesional structures and white matter were not included into the experimental analysis.The results show that in comparison to interictal period (at about 8–6 minutes before seizure onset), there was a statistically significant decrease in PD2 complexity in the preictal period at about 2 minutes before seizure onset in all 64 intracranial channels localized in various brain sites that were included into the analysis and in 3 scalp EEG channels as well. Presented results suggest that using PD2 in EEG analysis may have significant implications for research of preictal dynamics and prediction of epileptic seizures.  相似文献   
10.
Linear polyurethanes (PUR-Dk) were prepared by reacting 4,4′-methylenediphenyl diisocyanate (MDI) with low-molecular-weight diols HO (CH2)k OH (k = 2, 3, 4, and 6) and fractionated by precipitation or extraction with mixtures of N,N-dimethylformamide (DMF) and dibutyl ether (DBE). The fractions were characterized by their weight-average molecular weights M w (light scattering) and intrinsic viscosities [η] in DMF (good solvent) and mixtures of DMF with DBE (poor solvents). The Kuhn statistical segment length lK was evaluated from the intrinsic viscosities in poor solvents. Low values of lK, (12 to 14) × 10−8 cm, indicate that benzene rings and virtual double bonds (urethane groups) confine neighbour interactions to bonds within the repeating units and assure independent rotations at the bonds adjoining them.  相似文献   
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