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131.
Background Percutaneous needle biopsy has many advantages over open biopsy in the treatment of neoplasms. However, the accuracy of the needle biopsy in the diagnosis of musculoskeletal tumors has not been established. It is essential to evaluate the accuracy and limitations of the procedure in musculoskeletal tumors. Methods The diagnoses from 66 needle biopsies (bone, 37; soft tissue, 29) performed on 64 consecutive patients using a jamshidi needle (bone tumors) or a Tru-cut needle (soft tissue tumors) were compared with the final diagnoses made by open biopsy and/or a definitive operation. Results Fifty-eight specimens (87.9%) were judged to be adequate for histological examination. It was technically difficult to obtain undamaged cores from very hard bony lesions or sclerotic cyst walls. A pathologist with experience in musculoskeletal tumors was able to differentiate malignant tumors from benign lesions in 98.3% of the cases (bone, 100%; soft tissue, 96.4%) and arrive at a specific diagnosis in 91.4% (bone, 100%; soft tissue, 82.1%) when adequate cores were obtained. It was troublesome to distinguish a well-differentiated liposarcoma from a benign lipoma, or inflammatory lesions from benign tumorous conditions. The overall accuracy for needle biopsy was 80.3% (bone, 81.1%; soft tissue, 79.3%). There was no morbidity related to the procedure. Conclusion The results indicate that meedle biopsy is a safe and accurate technique for diagnosing musculoskeletal tumors.  相似文献   
132.
We report a case of bilateral internal carotid artery (ICA) stenosis treated with stenting. A 78-year-old man suffered from vascular dementia and left hemiparesis, and, by magnetic resonance angiogram (MRA), was diagnosed as having bilateral ICA stenosis. Cerebral angiogram showed severe, bilateral ICA stenosis (right; 88%, left; 93%) and xenon single photon emission tomography (SPECT) showed severely decreased cerebral blood flow (CBF) and cerebrovascular reactivity (CVR). We performed bilateral carotid angioplasty with self-expanding stents. Both CBF and CVR were improved bilaterally after the operation. The patient was discharged without neurological deficits. Carotid stenting may be an alternative treatment for severe ischemia caused by severe, bilateral ICA stenosis.  相似文献   
133.
We studied 13 consecutive patients with bone and soft tissue sarcomas of the hand and wrist. Chondrosarcoma, Ewing's sarcoma, synovial sarcoma and epithelioid sarcoma were the most frequent histological diagnoses. Limb-sparing surgery was performed in ten patients but eventually three patients required an amputation. Surgical margins were wide in nine patients and marginal in four. Adjuvant therapy for nine patients consisted of chemotherapy in five and chemotherapy with radiation in four. Local recurrence occurred in two patients with epithelioid sarcoma. There was no significant relationship between surgical margin and local recurrence. Distant metastasis occurred in four patients. The 5-year survival rate was 66%. The mean functional score was 87%. Our study indicates that treatment consisting of resection of these tumours with either a wide margin or a marginal margin followed by adjuvant radiation appeared to be safe and resulted in an acceptable degree of limb function except in the patients with epithelioid sarcoma.  相似文献   
134.
In this study, inducible nitric oxide synthase (iNOS) expression in a series of 158 human primary brain tumors was analyzed. To gain some insight into the biological significance of iNOS expression in tumor cells, comparative immunohistochemical analyses were employed to characterize the expression of iNOS, superoxide dismutase (SOD) proteins (SOD1 and SOD2), Ki-67 antigen (MIB-1) and p53 protein in these cells. Sixteen (39.0%) of the 41 glioblastoma multiforme (GBM) specimens showed iNOS immunoreactivity. Positive immunoreactions with iNOS were also detected in 2/8 anaplastic astrocytomas, 1/17 astrocytomas, 1/14 medulloblastomas and 1/11 primitive neuroectodermal tumors, but no positive reactions were observed in oligodendrogliomas (0/11), ependymomas (0/5), schwannomas (0/21), meningiomas (0/23) or pituitary adenomas (0/7). The MIB-1 labeling index of GBMs that expressed iNOS was significantly higher than that of GBMs that did not (0.025< P <0.05, Wilcoxon rank-sum test). Unlike iNOS-negative tumors, all iNOS-positive tumors coexpressed SOD1 or SOD2. In particular, there was a significant correlation between iNOS induction and SOD1 expression (P =1.65x10(-10), Fisher's exact test) in GBM specimens. There was no significant relationship between iNOS and p53 protein in any type of primary brain tumor (P >0.05, Fisher's exact test). No significant immunohistochemical reactions with iNOS, MIB-1 or p53 protein were observed in normal brain tissue sections. We conclude that primary brain tumors express iNOS, and that iNOS expression in brain tumor cells may depend, in part, on cellular proliferation potential. Based on the fact that SOD1 scavenges oxidative-stress species originating from large amounts of nitric oxide (NO) produced by iNOS, iNOS-expressing brain tumor cells may protect themselves against NO cytotoxicity by overinducing SOD1.  相似文献   
135.
To clarify the trophic mechanism of residual anterior horn cells affected by sporadic amyotrophic lateral sclerosis (SALS) and familial ALS (FALS) with superoxide dismutase 1 (SOD1) mutations, we investigated the immunohistochemical expression of hepatocyte growth factor (HGF), a novel neurotrophic factor, and its receptor, c-Met. In normal subjects, immunoreactivity to both anti-HGF and anti-c-Met antibodies was observed in almost all anterior horn cells, whereas no significant immunoreactivity was observed in astrocytes and oligodendrocytes. Histologically, the number of spinal anterior horn cells in ALS patients decreased along with disease progression. Immunohistochemically, the number of neurons negative for HGF and c-Met increased with ALS disease progression. However, throughout the course of the disease, certain residual anterior horn cells co-expressed both HGF and c-Met with the same, or even stronger intensity in comparison with those of normal subjects, irrespective of the reduction in the number of immunopositive cells. Western blot analysis revealed that c-Met was induced in the spinal cord of a patient with SALS after a clinical course of 2.5 years, whereas the level decreased in a SALS patient after a clinical course of 11 years 5 months. These results suggest that the autocrine and/or paracrine trophic support of the HGF-c-Met system contributes to the attenuation of the degeneration of residual anterior horn cells in ALS, while disruption of the neuronal HGF-c-Met system at an advanced disease stage accelerates cellular degeneration and/or the process of cell death. In SOD1-mutated FALS patients, Lewy body-like hyaline inclusions (LBHIs) in some residual anterior horn cells exhibited co-aggregation of both HGF and c-Met, although the cytoplasmic staining intensity for HGF and c-Met in the LBHI-bearing neurons was either weak or negative. Such sequestration of HGF and c-Met in LBHIs may suggest partial disruption of the HGF-c-Met system, thereby contributing to the acceleration of neuronal degeneration in FALS patients.  相似文献   
136.
A Japanese boy developed febrile seizures and gait disturbance at 2 years of age and dysarthria a year later. He had generalized tonic-clonic seizures once or twice a year from the age of 4 years. Brain computed tomography (CT) showed symmetric low-density areas in the white matter of the frontal lobes. However, abnormal CT findings fluctuated occasionally, with no apparent change in clinical manifestations. Clinical evaluation at 9 years of age revealed hyper-reflexia, psychomotor retardation, megalencephaly, and slurred nasal speech. Magnetic resonance imaging showed white matter abnormalities, predominantly in the frontal lobes. He was a heterozygote of the Arg239Cys mutation of the glial fibrillary acidic protein gene and was diagnosed with Alexander's disease. Fluctuation of CT findings in white matter may reflect blood-brain barrier dysfunction in Alexander's disease.  相似文献   
137.
Visual illusion induced by sound   总被引:6,自引:0,他引:6  
We present the first cross-modal modification of visual perception which involves a phenomenological change in the quality-as opposed to a small, gradual, or quantitative change-of the percept of a non-ambiguous visual stimulus. We report a visual illusion which is induced by sound: when a single flash of light is accompanied by multiple auditory beeps, the single flash is perceived as multiple flashes. We present two experiments as well as several observations which establish that this alteration of the visual percept is due to cross-modal perceptual interactions as opposed to cognitive, attentional, or other origins. The results of the second experiment also reveal that the temporal window of these audio-visual interactions is approximately 100 ms.  相似文献   
138.
Summation of initiation activities of different carcinogens in the liver after partial hepatectomy (PH) was investigated with reference to induction of glutathione S-transferase placental form (GST-P) positive foci. Firstly, effects of repeated administration of 1,2-dimethylhydradine (DMH) were compared with the results of a single administration of the same total dose (Expt. I). Subsequently, we studied summation of initiation potential with serial administration of DMH with diethylnitrosamine (DEN) or N-bis (2-hydroxpropyl)-nitrosamine (DHPN). In Expt. I, induction of GST-P-positive foci by multiple low-dose administration was equal to that with the single large-dose treatment. In order to avoid toxicity in hepatectomized rats, the low repeated-dose approach appeared superior. In Expt. II, the numbers of GST-P-positive foci in the groups treated with DMH plus DHPN or DMH plus DEN were significantly higher than those in the groups receiving the carcinogens singly. It is concluded that there is summation of initiation potential with doses of a single or multiple carcinogens. These results suggest that the present initiation assay model is useful to investigate summation of initiation activities of various environmental chemicals.  相似文献   
139.
We studied the pharmacokinetics of CPT-11 with intraperitoneal administration in a patient with a PTCD tube. The patient had advanced gastric cancer with peritoneal metastasis. CPT-11 was administrated in a dose of 40 mg and the intraperitoneal, plasma and bile levels of CPT-11, SN-38 and SN-38 glucuronide (SN-38 GLU) were measured periodically. The results showed that the periodical concentration pattern of CPT-11, SN-38 and SN-38 GLU in the bile was closely related to that of CPT-11 in the abdominal cavity.  相似文献   
140.
We have produced a novel rat IgG(2a) monoclonal antibody against a stage-specific fetal brain glycoprotein of 68 kDa (FGP68), and succeeded in applying it to staining paraffin sections. To gain some insight into the pathobiological significance of this FGP68, this monoclonal antibody was used in immunohistochemical studies to compare the expression of FGP68 and Ki-67 antigen (MIB-1) in 235 primary brain tumors. Approximately half of the glioblastomas multiforme (GBMs) (44/75) and anaplastic astrocytomas (9/17) as well as some astrocytomas (5/30), medulloblastomas (2/14) and primitive neuroectodermal tumors (2/10) had tumor cells that expressed FGP68; however, pilocytic astrocytomas (0/7), oligodendrogliomas (0/15), ependymomas (0/6), schwannomas (0/21), meningiomas (0/22) and pituitary adenomas (0/18) did not express FGP68. The values of the MIB-1 labeling index were statistically higher in GBMs (0.005< P<0.01, Wilcoxon rank-sum test) and anaplastic astrocytomas (0.025< P<0.05) that expressed FGP68 than in those that did not. Normal brain tissue from 20 individuals aged 3-75 years was negative for FGP68 and MIB-1. We conclude that primary brain tumors express FGP68, one of the oncofetal proteins derived from fetal brain, and that FGP68 expression in certain brain tumor cells may depend, in part, on proliferation potential. Based on the possibility that the stage-specific FGP68 plays an important role in brain embryogenesis, some of FGP68-expressing tumor cells might phylogenetically revert to more primitive cells.  相似文献   
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