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171.
Glioblastoma (GBM) is a malignant brain tumor with a poor prognosis. The standard postoperative chemotherapy is temozolomide (TMZ), which does not greatly improve survival. The DNA repair gene O-6-methylguanine-DNA methyltransferase (MGMT) contributes to the response of TMZ-induced DNA damage. The commonly prescribed antiepileptic drug levetiracetam (LEV) has been shown to enhance TMZ’s antitumor effect via inhibition of histone deacetylases (HDACs), but the therapeutic advantages of the LEV and TMZ combination remain poorly understood. Mechanisms of response to chemotherapy include apoptosis and mitotic catastrophe, and recent studies have suggested that premature senescence may also be invoked when cancer cells are exposed to therapeutic agents. In our study, we evaluated cell proliferation and premature senescence after single and combined treatments of TMZ and LEV in two GBM cell lines that differ in TMZ sensitivity caused by the absence (A172) or presence (T98) of the MGMT protein. Both LEV and TMZ reduced cell proliferation in a dose-dependent manner in A172 cells. A senescent-like phenotype, as determined by β-galactosidase activity, was induced by both TMZ and LEV. Overall, there was a greater effect following combined treatment compared to the monotherapy groups. Thus, LEV appears to have a tumor-suppressive effect and induces cellular senescence, and combined treatment of LEV and TMZ enhanced these effects. because LEV treatment results in few adverse effects, its use in GBM treatment may allow for reduction of the TMZ dose to enhance the clinical efficacy of TMZ chemotherapy and improve quality of life.  相似文献   
172.
Features of hepatocellular carcinoma (HCC) observed by contrast-enhanced ultrasonography (CEUS) were compared to pathological features of corresponding resected HCC specimens, to evaluate the ability of CEUS to depict the pathological features of HCC. We investigated 50 HCC nodules that were treated by surgical resection. All nodules had been examined by CEUS with intravenous contrast agent (Levovist) before surgery. CEUS findings were divided into three phases for evaluation and classification of enhancement patterns: two vascular phases (arterial phase and portal venous phase) and the delayed phase. Pathological examination focused on differentiation and on the presence or absence of a tumor capsule, intratumoral septum, and intratumoral necrosis. All 21 nodules that showed a linear or annular vessel around the tumor margin in the arterial phase had capsular formation. Of the 27 nodules that showed heterogeneous perfusion in the portal venous phase, 21 (77.8%) had an intratumoral septum and 23 (85.2%) showed intratumoral necrosis. All nodules that were depicted as a defect with an unclear margin in the delayed phase were well-differentiated HCCs, whereas all nodules that were depicted as a defect with a clear margin were moderately or poorly differentiated HCCs. From our observations, the arterial, portal venous, and delayed phases of CEUS could reflect different pathological aspects of HCC. Some pathological characteristics of HCC might be evaluated preoperatively and non-invasively, by means of combined analysis of three phases of CEUS findings.  相似文献   
173.
Pain often outlasts its usefulness as warning and aid in wound healing, and becomes chronic and intractable after tissue damage and nerve injury. Many molecules have been implicated as mediators and modulators in persistent pain such as hyperalgesia and tactile pain (allodynia). We previously showed that prostaglandin (PG) E(2), PGF(2alpha) or the neuropeptide nociceptin, also called orphanin FQ (N/OFQ) administered intrathecally (i.t.) produced allodynia in conscious mice. In the present study, we examined the relationship of pain responses between PGs and N/OFQ using the N/OFQ receptor (NOP) antagonist, N-(4-amino-2-methylquinolin-6-yl)-2-(4-ethylphenoxy-methyl)benzamide monohydrochloride (JTC-801), and in mice lacking the N/OFQ prepropeptide (ppN/OFQ(-/-)) and the NOP receptor (NOP(-/-)). JTC-801 dose-dependently blocked the N/OFQ- and PGE(2)-induced allodynia, but not the PGF(2alpha)-induced one. Neither N/OFQ nor PGE(2) induced allodynia in NOP(-/-) mice. By contrast, the N/OFQ-induced allodynia was not affected by inhibition of PG production by a 60-min pretreatment with the non-steroidal anti-inflammatory drug, indomethacin. Among PGE receptor (EP) subtype-selective agonists, the EP4 agonist, AE1-329, markedly stimulated the release of N/OFQ from spinal slices and induced allodynia. AE1-329 also increased nitric oxide production in spinal slices using fluorescent nitric oxide detection, which was blocked by pretreatment with JTC-801. Conversely, PGE(2)-induced allodynia was not observed in ppN/OFQ(-/-) mice. N/OFQ immunoreactive puncta were colocalized with EP4. Taken together, these results demonstrate that PGE(2) induced allodynia by stimulation of N/OFQ release in the spinal cord via EP4 receptor subtypes.  相似文献   
174.
A familial case of limb pain is described. Frequent vascular pain appeared during early childhood in affected individuals, often with predominance in the lower extremities. This pain subsided in patients during adolescence, when they began to suffer from typical migraine. The limb pain was moderate to severe, and refractory to analgesic and anti-migraine medications. Limb temperature was cold at the onset of pain, and became warm during the painful attacks. Plasma substance P and calcitonin gene-related peptide were elevated during the episodic pain. We propose this condition is a new precursor etiology of migraine, with possible autosomal dominant inheritance.  相似文献   
175.
176.
Notch signaling plays an important role in the process of cell-fate assignation during nervous system development. DNER is a neuron-specific transmembrane protein carrying extracellular EGF-like repeats and is expressed in somatodendritic regions. In vitro studies demonstrated that DNER mediates Notch signaling by cell-cell interaction. In the cerebellum, DNER is abundantly expressed in Purkinje cells and moderately in granule cells. DNER-knockout mice showed motor discoordination. The mutant cerebellum showed morphological impairments of Bergmann glia and multiple innervation between climbing fibers and Purkinje cells. Moreover, glutamate clearance at the synapses between parallel fibers and Purkinje cells was significantly weakened, and the expression of GLAST, a glutamate transporter in Bergmann glia, was reduced in the mutant cerebellum. Therefore, DNER contributes to the morphological and functional maturation of Bergmann glia via the Notch signaling pathway, and is essential for precise cerebellar development.  相似文献   
177.
Hereditary pancreatitis (HP) is an autosomal‐dominant gene disorder. The affected genes have been identified as the cationic trypsinogen (CT) gene and the serine protease inhibitor Kazal type 1 (SPINK1) gene. These gene abnormalities alone, however, do not necessarily regulate the onset or severity of pancreatitis, suggesting the involvement of other gene abnormalities and environmental factors. Reported herein is the case of a 9‐year‐old boy with early‐onset HP due to mutations in the CT and SPINK1 genes. The patient had a p.R122H heterozygous mutation in the CT gene and a p.N34S heterozygous mutation in the SPINK1 gene. The father had heterozygous mutation of the SPINK1 gene, and the mother had heterozygous mutation of the CT gene, although neither had a prior history of pancreatitis. In this patient, early onset of HP was attributed to the presence of gene abnormalities in the CT and SPINK1 genes.  相似文献   
178.

Objective

We previously reported on the role of cytoreduction in 248 patients with surgical stage IVb endometrial cancer (EMCA). This study aimed to evaluate the clinical characteristics, prognosis according to initial treatment, and impact of preoperative chemotherapy in the overall population of patients with clinical and surgical stage IVb EMCA.

Methods

A multi-institutional retrospective analysis was performed in 426 patients diagnosed with clinical and surgical stage IVb EMCA from 1996 to 2005. Factors associated with overall survival (OS) were identified using univariate and multivariate analyses.

Results

The median OS for all 426 patients was 14 months. Patients were divided into three groups according to their initial treatment: primary surgery group (n = 279), primary chemotherapy group (n = 125), and palliative care group (n = 22). The median OS times for these groups were 21, 12, and 1 month, respectively (p < 0.0001). Patients in the primary surgery group had better performance status (PS) and lower numbers of extra-abdominal metastases than those in the primary chemotherapy group. Multivariate analysis identified good PS, endometrioid histology, absence of clinical intra-abdominal stage IVb metastasis, hysterectomy, and chemotherapy as independent predictors of OS. In the primary chemotherapy group, 59 patients subsequently underwent surgery, and these patients had similar OS to those in the primary surgery group.

Conclusions

Hysterectomy and chemotherapy may prolong OS in selected patients with stage IVb EMCA. Our data suggest that primary chemotherapy followed by surgery may be a useful treatment choice in patients not suitable for primary surgery.  相似文献   
179.
Nociceptin, the endogenous peptide ligand for opioid receptor like-1 (ORL1) receptor, has been implicated in the inflammation and pain in the skin. We examined whether nociceptin is a pruritogen in mice. Intradermal injections of nociceptin (1-100 nmol per site) concentration dependently increased scratching in ICR mice; the effect started within 1 min, peaked at 10-20 min, and almost subsided by 30 min. The nociceptin action was absent in ORL1 receptor-deficient (ORL1(-/-)) mice. Systemic, but not local, treatment with naloxone significantly inhibited scratching induced by nociceptin. The action of nociceptin was inhibited by the leukotriene B(4) receptor antagonist ONO-4057 and azelastine, which inhibits the action and production of leukotriene B(4) in the skin. Prepronociceptin and ORL1 receptor mRNAs were substantially expressed in the skin, whereas their expression levels were very low in the dorsal root ganglia. In the skin, nociceptin- and ORL1 receptor-like immunoreactivities were localized in the epidermis. Administration of nociceptin to primary cultures of keratinocytes from ICR and C57BL/6 (ORL1(+/+)) mice, but not ORL1(-/-) mice, produced leukotriene B(4). The results suggest that nociceptin acts on ORL1 receptor on the keratinocytes to produce leukotriene B(4), which induces itch-associated responses in mice.  相似文献   
180.
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