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951.
952.
Japanese flowering cherry (Prunus subgenus Cerasus) cultivars, which are characterized by beautiful flowers, have been developed through hybridization among wild Prunus taxa. The long history of cultivation has caused significant confusion over the origins of these cultivars. We conducted molecular analysis using nuclear simple sequence repeat (SSR) polymorphisms to trace cultivar origins. Bayesian clustering based on the STRUCTURE analysis using SSR genotypes revealed that many cultivars originated from hybridization between two or more wild species. This suggests that morphological variations among flowering cherry cultivars probably arose through a complex sequence of hybridizations. Our findings generally supported estimates of the origins of cultivars based on morphological study, although there were some exceptions.  相似文献   
953.
Bacterial pathogens utilize pore-forming toxins or sophisticated secretion systems to establish infection in hosts. Recognition of these toxins or secretion system by nucleotide-binding oligomerization domain leucine-rich repeat proteins (NLRs) triggers the assembly of inflammasomes, the multiprotein complexes necessary for caspase-1 activation and the maturation of inflammatory cytokines such as IL-1β or IL-18. Here we demonstrate that both the NLRP3 and NLRC4 inflammasomes are activated by thermostable direct hemolysins (TDHs) and type III secretion system 1 (T3SS1) in response to V. parahaemolyticus infection. Furthermore, we identify T3SS1 secreted effector proteins, VopQ and VopS, which induce autophagy and the inactivation of Cdc42, respectively, to prevent mainly NLRC4 inflammasome activation. VopQ and VopS interfere with the assembly of specks in infected macrophages. These data suggest that bacterial effectors interfere with inflammasome activation and contribute to bacterial evasion from the host inflammatory responses.  相似文献   
954.
This study observed the behavioral characteristics of 122 steers in eight pens and 1,136 steers at six pastures. Nonhuman animals kept in pens performed less nutritive oral behaviors and more nonnutritive oral behaviors than animals kept at pasture. Although these could not be described as stereotypies, they did represent a replacement of nutritive oral behaviors by nonnutritive oral behaviors, rather than simply an increase in resting time. This could be indicative of a level of oral frustration. At pasture, there was a greater proportion of oral behaviors in animals with low pasture availability as compared to high availability, but this was an increase in nutritive oral behaviors rather than nonnutritive oral behaviors. Factors other than oral frustration—for example, rumen fill—probably drove this increase.  相似文献   
955.
In this study, we investigated whether a relationship exists between the levels of urate in vivo and lipid peroxidation during exercise. Seven healthy male subjects performed exhaustive cycling exercise under the following three conditions. The levels of urate, thiobarbituric acid reactive substances (TBARS) and allantoin in plasma and urine were examined before exercise and during a 3 h recovery period. (1) Benzbromarone administration experiment: benzbromarone (an uricosuric agent) was administered orally the day before exercise. (2) IMP administration experiment: inosine 5′-monophosphate disodium salt (a precursor of urate) was administered orally the day before exercise. (3) Control experiment: no test substance was administered. The main results obtained were as follows. Plasma urate levels and total peroxyl radical-trapping antioxidant parameter (TRAP) for deproteinized plasma in the resting period significantly decreased depending on the treatment, in the order of IMP > control > benzbromarone. A significant positive correlation was evident between plasma urate levels and TRAP values for deproteinized plasma. The increase in plasma levels of allantoin was observed only in the case of IMP treatment. A significant negative correlation between plasma levels of urate in the resting period and the amounts of urinary TBARS excreted during the recovery period was recognized. These results suggest that the urate level in vivo before exercise is a factor influencing lipid peroxidation during exhaustive exercise. Furthermore, these findings support the view that urate may serve as an important free-radical scavenger in vivo.  相似文献   
956.

Background

Progressive multifocal leukoencephalopathy (PML), a fatal demyelinating disease caused by JC virus (JCV), occurs mainly in immunocompromised patients. While JCV DNA is detected in the cerebrospinal fluid (CSF) from a certain proportion of patients suspected of having PML, JCV-negative patients may also develop brain lesions due to other infectious agents. This study assessed the prevalence of six herpesviruses in the CSF from patients diagnosed with or suspected of PML.

Methods

Two hundred and ninety-nine CSF specimens and clinical data were collected from 255 patients, including 31 confirmed PML cases. Quantitative PCR assays were carried out to detect the genomic DNA of JCV, herpes simplex virus (HSV), varicella-zoster virus (VZV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), and human herpesvirus 6 (HHV-6).

Results

Herpesvirus DNAs were detected in the CSF specimens from 29 of 255 patients (11.4%). HSV-1 and CMV were detected in JCV-negative patients, whereas VZV and EBV were detected in both CSF JCV-positive and -negative individuals. The herpesvirus-positive patients had underlying disorders that caused immunosuppression, such as HIV infection, congenital immunodeficiencies, and hematologic malignancies, and presented with neurologic symptoms and MRI lesions, mainly in the cerebral white matter. The median values of CSF cell counts and protein levels in the herpesvirus-positive patients were slightly higher than those in the PML patients.

Conclusions

The results demonstrate that herpesviruses are occasionally detected in the CSF from PML patients and immunocompromised individuals suspected of having PML. Thus, this study provides a significant basis for the diagnosis and treatment of neurological disorders in immunocompromised patients.
  相似文献   
957.
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Cancer cells eventually acquire drug resistance largely via the aberrant expression of ATP-binding cassette (ABC) transporters, ATP-dependent efflux pumps. Because cancer cells produce ATP mostly through glycolysis, in the present study we explored the effects of inhibiting glycolysis on the ABC transporter function and drug sensitivity of malignant cells. Inhibition of glycolysis by 3-bromopyruvate (3BrPA) suppressed ATP production in malignant cells, and restored the retention of daunorubicin or mitoxantrone in ABC transporter-expressing, RPMI8226 (ABCG2), KG-1 (ABCB1) and HepG2 cells (ABCB1 and ABCG2). Interestingly, although side population (SP) cells isolated from RPMI8226 cells exhibited higher levels of glycolysis with an increased expression of genes involved in the glycolytic pathway, 3BrPA abolished Hoechst 33342 exclusion in SP cells. 3BrPA also disrupted clonogenic capacity in malignant cell lines including RPMI8226, KG-1, and HepG2. Furthermore, 3BrPA restored cytotoxic effects of daunorubicin and doxorubicin on KG-1 and RPMI8226 cells, and markedly suppressed subcutaneous tumor growth in combination with doxorubicin in RPMI8226-implanted mice. These results collectively suggest that the inhibition of glycolysis is able to overcome drug resistance in ABC transporter-expressing malignant cells through the inactivation of ABC transporters and impairment of SP cells with enhanced glycolysis as well as clonogenic cells.  相似文献   
960.
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