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11.
One of the mechanisms of cytotoxicity by tumor necrosis factor (TNF) is the induction of reactive oxygen molecules. Cells producing endogenous tumor necrosis factor (enTNF) show resistance to the cytotoxicity of exogenous TNF by scavenging the reactive oxygen molecules. The intracellular hydroxyl radical production is also known to be involved in the heat-induced cytotoxicity. In the present study, we therefore examined the possibility that enTNF may act as a protective protein against the heat-induced cytotoxicity in a manner similar to that of exogenous TNF. Heat-sensitive L-M (mouse tumorigenic fibroblast) cells, originally expressing no enTNF, were transfected with a human TNF expression vector to produce enTNF. The stable transfectants showed apparent resistance to heat treatment. Conversely, when HeLa (human uterine cervical cancer) cells, originally producing an appreciable amount of enTNF, were transfected with an antisense TNF mRNA expression vector to inhibit enTNF synthesis, their heat sensitivity was enhanced. Furthermore, L-M cells which were transfected with nonsecretory human TNF expression vector also acquired resistance to heat treatment. In these cells, heat resistance correlated well with expression of enTNF and intracellular levels of manganous superoxide dismutase. These results indicate that enTNF exerts its intracellular protective effect against the heat-induced cytotoxicity by scavenging reactive oxygen with induced manganous superoxide dismutase in a manner similar to that found in cells treated with exogenous TNF.  相似文献   
12.
The vitronectin receptor (VNR) is an integrin which consists of an alpha-subunit which can associate with multiple beta-subunits. A polyclonal antibody to this integrin weakly stained resting microglia in white matter of control brain and strongly stained reactive microglia in both gray and white matter of Alzheimer brain. This antibody, as well as a monoclonal antibody to beta 3, stained some platelets in capillaries of both control and Alzheimer tissue. When the antiserum was immunoabsorbed with a preparation enriched in the alpha-chain of the vitronectin receptor, it failed to stain microglial cells, but continued to stain platelets. When it was immunoabsorbed with a peripheral blood platelet preparation, all immunostaining was abolished. These results indicate that the vitronectin receptor of microglia is associated with a beta-chain different from beta 3, but that beta 3 is expressed by some platelets in brain capillaries. An antibody to vitronectin itself stained senile plaques and neurofibrillary tangles in Alzheimer entorhinal cortex, but only residual plasma in control tissue. Senile plaques positive for vitronectin had microglial cores strongly positive for the vitronectin receptor. The high levels of vitronectin receptor on reactive microglia in areas containing extracellular vitronectin suggest the possibility that vitronectin is serving an opsonizing function for microglial phagocytosis.  相似文献   
13.
As a model system for mucocutaneous lymph node syndrome (MCLS), we have advocated and used mice which had been rendered tolerant to Streptococcus pyogenes-associated antigens by neonatal infection with group A fteta-hemolytic streptococci, because these mice have shown a variety of peculiar bioimmunological characteristics bearing a striking resemblance to those of MCLS patients. The results of our current investigations reaffirmed the reliability of the animal model by indicating that mice subjected to neonatal infection with 5. pyogenes , or inoculation with streptococcal pyrogenic exotoxin (SPE) in Freund's adjuvant, were perfect counterparts of patients with MCLS on account of their platelet activation and hyperaggregability in response to provocative treatment, which are familiar findings in this disease.  相似文献   
14.
A 76-year-old man, whose carotid bodies had been resected for treatment of bronchial asthma 40 years previously was admitted for evaluation of abnormal arterial blood gases and exertional dyspnea. The case was diagnosed clinically as chronic pulmonary emphysema. His peripheral chemoreceptor function, estimated by hypoxic ventilatory and P0.1 response tests and withdrawal test was non-functioning. His PaCO2 value tended to rise over 50 Torr either after light exercise or during airway infection, though it was normal at rest. In addition his dyspnea had continued for 40 years in spite of carotid body resection. It was concluded that the effect of carotid body resection lasts more than 40 years and it does not have a good effect on COPD.  相似文献   
15.
Radical lymph node dissection for cancer of the thoracic esophagus.   总被引:1,自引:0,他引:1       下载免费PDF全文
OBJECTIVE: The authors documented the localization and frequency of lymphatic spread in squamous cell carcinoma of the thoracic esophagus and evaluated the influence of radical systematic lymph node dissection on patient survival. SUMMARY BACKGROUND DATA: From accumulated surgical experience, it was suggested that some of the patients with lymph nodal involvement from cancer could be cured by its clearance. However, it is only recently that cancer of the esophagus has been evaluated in terms of analyzing lymphatic spread and results of lymphadenectomy. METHODS: Among 1298 patients admitted to the Toranomon Hospital between 1973 and 1993, 913 (70.3%) had resections, including curative and palliative procedures. For this study, 717 patients with TNM RO (resection with no residual tumor at operation in TNM classification) were analyzed. Survival was compared between groups of patients with less extensive thoracoabdominal (two-field) dissections and extensive collothoracoabdominal (three-field) dissections. RESULTS: Comparative study revealed that 5-year survival rate for TNM RO patients after free-field dissection (55.0%) was significantly better (log rank test, p = 0.0013) than the rate after two-field dissection (38.3%). The results were particularly significant in subgroups with stage III and IV (because of nodal factor). Overall 5-year survival rate after all resections was 42.4%. CONCLUSIONS: The role of radical lymph node dissection in cancer of the thoracic esophagus evaluated. Long-term survival was compared between two groups with two- and three-field dissection. It was concluded that survival rate was significantly better in patients with extensive three-field dissection.  相似文献   
16.
17.
Expression of six proto-oncogenes (fos, myc, myb, Ki-ras, Ha-ras, and N- ras) in 43 cases of non-Hodgkin's lymphoma was analyzed by means of in situ hybridization. Biotinylated DNA probes of the six oncogenes and those of immunoglobulin H (IgH) gene and T-cell receptor beta (TCR beta) chain gene were used. The results of in situ hybridization performed under blind conditions by IgH gene and TCR beta chain gene probes were compatible with those of typing by cell surface markers. The nuclear protein-related proto-oncogenes, fos, myc, and myb, were expressed in about 70% to 80% of all cases regardless of phenotype, histology, or histologic grade. On the contrary, genes of ras family were expressed in more limited numbers of cases except for the Ki-ras gene, which was more frequently expressed by cases of the T-cell immunophenotype with a high malignancy grade. The results of dot hybridization with RNA extracted from some cases were compatible with those of in situ hybridization, further demonstrating the specificity of in situ hybridization.  相似文献   
18.
Functional changes in sigma receptors were examined after behavioral sensitization induced by repeated methamphetamine treatment. Rats received either saline or 4 mg/kg methamphetamine for 14 days. (+)3-(3-hydroxyphenyl)-N-(1-propyl)piperidine ((+)-3-PPP), a sigma receptor agonist, was given as challenge after various periods of abstinence. (+)-3-PPP at doses greater than 6 mg/kg stimulated several forms of behavior in naive rats. (+)-3-PPP at 12 and 24 mg/kg produced more frequent rearing and more intense stereotyped sniffing and repetitive head movements in rats previously sensitized with methamphetamine than in saline-pretreated rats. The augmented response to (+)-3-PPP in methamphetamine-treated rats was maintained for at least one month. The augmented response to (+)-3-PPP was reversed by the combined administration of 100 mg/kg (+/-)-sulpiride, a D2 dopamine receptor antagonist, and 30 mg/kg BMY 14802, a sigma receptor antagonist. These results suggest that repeated methamphetamine treatment induces persistent supersensitivity in sigma receptors and that it may subsequently activate the dopamine system.  相似文献   
19.
Samples from seventy autopsy cases ranging from 27 to 79 years of age who had shown no evidence of renal or malignant diseases were examined histologically to clarify renal changes with age. We evaluated scores for renal histological change and referred the scores to clinical laboratory data; blood pressure, complete blood counts (RBC count, hematocrit, hemoglobin), serum chemistry values (creatinine, urea nitrogen, total cholesterol, total protein, sodium, potassium, chloride) and urinalysis (protein, sediment). We found the score to be related to serum creatinine level, blood urea nitrogen level and the degree of hematuria but not related to the other factors. The progression of arteriosclerosis, tubulo-interstitial change and global sclerosis were found to be severe with ageing. Also renal weight decreased with increasing age. However there were great differences among individuals in the extent of changes. We could not assume histological changes were generally severe in those of more than 55-65 years of age. It was impossible to clarify renal states only with clinical findings. Some kidneys had severe histological changes though less than 2.0 mg/dl of serum creatinine level. It suggests that living relatives and cadavers over 60 years old can be donors for renal transplantation when there are no significant findings of abnormality in preoperative evaluations of their physical state. If insufficient examinations are done, we cannot determine which of them will be good donors. Therefore preoperative biopsy is the best way to evaluate donor suitability. To evaluate only clinical data, it is necessary that serum creatinine level be less than 1.2 mg/dl, blood urea nitrogen level be less than 23 mg/dl and there be no hematuria.  相似文献   
20.
SPECT of the skull was performed on twelve patients with histologically proven nasopharyngeal carcinoma using newly developed three detectors SPECT system (Toshiba GCA 9300A) mounted with fan-beam collimators, for the purpose of early detection of skull base involvement of the disease. This SPECT system has extremely improved resolution with FWHM of 8 mm in the center, and it provides clear tomographic images of the skull which has anatomically complex structure. SPECT image was taken 3 hours after injection of 740 MBq (20 mCi) of 99mTc-MDP following whole body skeletal survey. In twelve patients with confirmed nasopharyngeal carcinoma, 8 patients showed positive findings on SPECT. Three of SPECT positive patients also showed destructive findings on CT. Other five positive patients did not show destructive findings on CT at their initial examinations, but in three of them CT findings turned to positive later. SPECT was superior to CT in early detection of skull base involvement. We believe that SPECT of the skull is a diagnostic tool for early detection of skull base involvement of nasopharyngeal carcinoma.  相似文献   
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