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991.
Urinary stone disease and bladder cancer are two of the most commonly seen urologic diseases in Taiwan. Tumor necrosis factor-alpha (TNF-alpha) is one of the cytokines secreted by macrophages and is related to a sequence of events in response to inflammation and cancer formation. We investigated the polymorphism of the TNF-alpha gene promoter -308 as a genetic marker in searching for the association between these two commonly seen urologic diseases. One hundred and fourteen patients with transitional cell carcinoma of the urinary bladder and 103 patients with calcium oxalate stone were compared with 150 healthy controls. The polymorphism was detected by polymerase chain reaction-based restriction analysis (Nco I endonuclease). The results revealed no significant differences between normal individuals and the patients with the two commonly seen urologic diseases (P > 0.05). We concluded that the polymorphism of the TNF-alpha promoter -308 is not a valid genetic marker for these two urologic diseases.  相似文献   
992.
We present an instance of successful use of an intubating laryngeal mask airway (LMA-Fastrach) and a Cook airway exchanger (CAE) for ventilation and intubation in a patient with severe ankylosing spondilitis (AS) receiving total hip arthroplasty. This measure may serve as an effective alternative for airway management in patients with difficult airway. A 61-year-old male was scheduled for right total hip arthroplasty because of degenerative osteoarthritis. He had been suffering from extensive ankylosing spondylitis, with the cervical spine markedly fixed in anterior flexion. Besides he could not open his mouth widely (35 mm when fully open) also because of ankylosis of jaw. Although we advised an awake fiberoptic tracheal intubation for anesthesia but he refused owing to a previous painful experience. After induction of anesthesia with glycopyrrolate, fentanyl, thiamylal sodium and succinylcholine, we inserted a # 5 Fastrach ILMA for primary airway maintenance. Then through the lumen of the ILMA we introduced the CAE as a guide for endotracheal tube (ETT) intubation. After applying the RAPI-FIT adapter to the CAE, we connected it to the capnography monitor for the confirmation of airway. We finally inserted an endotracheal tube into the trachea using the CAE as a guide. The whole procedure was uneventful and smooth. In sum, the modified Fastrach intubation method may facilitate tracheal intubation in patients with severe ankylosing spondilitis. It may be an alternative way for successful airway management in patients with difficult airway.  相似文献   
993.
Chew WY  Tsai TM 《Hand Clinics》2001,17(3):395-410, viii
Major amputations remain a challenge to the replantation surgeon. Proper patient selection, good surgical skills, and cooperation among the patient, surgeon, and rehabilitation team help achieve a better outcome.  相似文献   
994.
Background: Betel nut chewing has long been a social habit in Taiwan and other Asian and tropical countries. It produces various autonomic and psychoneurologic effects including tachycardia, flushing, warmth, cholinergic activation, alertness, and euphoria. Although the oral carcinogenic effects are well known, data concerning its acute toxicity are few. To better understand the toxicity of betel nut, cases reported to the Taiwan Poison Control Center as probable or possible betel nut-related toxicity (January 1988-June 1998) were reviewed. In the 17 cases suitable for review (14 males, 3 females, age 21 to 60 years), the most common manifestations were tachycardia/palpitations (7); tachypnea/dyspnea (6); hypotension and sweating (5); vomiting, dizziness, and chest discomfort (4); abdominal colic, nausea, numbness, and coma (3); and acute myocardial infarction and related manifestations (2). The reported quantity of betel nut used was low (1 to 6 nuts), except an extract of 100 betel nuts was used in 1 case and 66 chewed in another. Most cases recovered within 24 hours after the exposure. One patient developed probable acute myocardial infarction and ventricular fibrillation and died despite repeated cardiac defibrillation. Although betel nut chewing is widespread, significant toxicity as reported to a poison center is rare. Because most betel nut-related effects are transient and mild in nature, the incidence of such events is likely to be underreported. Nevertheless, betel nut chewing can produce significant cholinergic, neurological, cardiovascular, and gastrointestinal manifestations. It is possible that it may aggravate cardiac diseases in susceptible patients but this hypothesis must be further investigated. Treatment is symptomatic. With timely support, rapid and complete recovery is anticipated but a small risk of major complications cannot yet be discounted.  相似文献   
995.
In this matched case-control study nested within the prospective Physicians' Health Study, we evaluated whether DNA damage in blood samples collected at enrollment significantly predicted risk, consistent with our hypothesis that cases have greater biological susceptibility to polycyclic aromatic hydrocarbons and other aromatic tobacco carcinogens. The subjects were 89 cases of primary lung cancer and 173 controls, all males, matched on smoking, age, and duration of follow-up. Aromatic-DNA adducts were measured in WBCs by the nuclease P1-enhanced (32)P-postlabeling method that primarily detects smoking-related adducts. Among current smokers, but not former or nonsmokers, there was a significant increase in mean adduct levels of cases compared with controls (11.04 versus 5.63; P = 0.03). "Healthy" current smokers who had elevated levels of aromatic DNA adducts in WBCs were approximately three times more likely to be diagnosed with lung cancer 1-13 years later than current smokers with lower adduct concentrations (odds ratio, 2.98; 95% confidence interval, 1.05-8.42; P = 0.04). We were not able to discern case-control differences in former smokers and nonsmokers. The findings are of interest because they suggest that individuals who become cases have greater biological susceptibility to tobacco carcinogens, a biological difference, which manifests most clearly while exposure is ongoing.  相似文献   
996.
997.
The involvement of glutamate in recall of the conditioned NK cell response   总被引:2,自引:0,他引:2  
The molecular mechanisms responsible for the conditioned enhancement of natural killer (NK) cell activity were investigated. The primary goal of the study was to examine the roles of glutamate and gamma-aminobutyric acid (GABA) in recall of the conditioned NK cell response. Both neurochemical blocking assay and high performance liquid chromatography (HPLC) technique were used in the study. Results from the neurochemical blocking assay demonstrated that glutamate but not GABA was required in recall of the conditioned NK cell response. NMDA but not the kainate/AMPA receptors, are believed to be involved. The levels of glutamate that were released and/or taken up also appeared to be critical in that interruption of glutamate release and/or uptake blocked the conditioned NK cell response. Results from the HPLC analysis, however, did not show any significant difference in the glutamate content between the conditioned and control brains.  相似文献   
998.
Nicotine acetylcholine receptors (nAChRs) are implicated in the pathogenesis of schizophrenia because the prevalence of smoking among schizophrenic patients is extraordinarily high, and nicotine has been demonstrated to improve some psychophysiological dysfunction in schizophrenics. In addition, recent studies have suggested linkage of the alpha(7) nAChR gene region in families of schizophrenics. In a population-based association study, we tested the hypothesis that the allelic variant, with a 2-bp deletion, of the human alpha(7) nAChR gene confers susceptibility to schizophrenic disorders. We genotyped alpha(7) nAChR in 146 patients with schizophrenic disorders and 151 controls. The results showed no significant difference in genotype or allele frequencies between schizophrenic patients and control subjects. This suggests that alpha(7) nAChR 2-bp deletion plays no major role in the pathogenesis of schizophrenic disorders. Other nAChR variants in schizophrenic disorders may need further investigation.  相似文献   
999.
Ethylene oxide is used as a sterilizer, a solvent, a plasticizer and in the manufacture of special solvents, antifreeze, polyester resins and non-ionic surfactants. Its toxicity is caused by an alkylating reaction with most organic substances in the body. Four workers, without any protection, managed the leakage of ethylene oxide from the collecting tank improperly on July 29, 2000. In the same factory, the overflow of ethylene oxide in process resulted in leakage of ethylene oxide again on Aug. 7, 2000. Two workers were poisoned despite wearing full-face respirators with ethylene oxide approved canisters. In these two events, the workers all smelled an ether-like odor. Six workers experienced nausea, vomiting, chest tightness, shortness of breath, dizziness, cough and ocular irritation. One worker had transient loss of consciousness. Oxygen therapy and supportive care were used. Patients were discharged in stable condition. The permissible exposure limit of ethylene oxide in air is 1 ppm as an eight hour TWA. Above 50 ppm, the odor threshold, a positive-pressure supplied air respirator is needed to protect the worker. Full-face respirators with ethylene oxide approved canisters could not protect our cases who smelled the odor and were exposed to an unknown concentration. It is important to wear positive-pressure self-contained breathing apparatuses equipped with full facepieces to clean up the contamination area and rescue the patients.  相似文献   
1000.
BACKGROUND: Expression levels of the retinoic acid receptors (RAR-alpha, RAR-beta, and RAR-gamma) are significantly different in neoplastic tissues compared with non-neoplastic tissues for some tumors. This study investigated whether retinoic acid receptor messenger RNA (mRNA) expression levels are altered in Barrett's esophagus and Barrett's adenocarcinoma tissues. METHODS: Relative mRNA expression levels of the RARs were quantified by using the ABI 7700 Sequence Detector (Taqman) system in Barrett's intestinal metaplasia (n = 15), dysplasia (n = 6), adenocarcinoma (n = 17), and matching normal esophagus tissues (n = 36). RESULTS: RAR-alpha expression was significantly increased, and RAR-gamma expression was significantly decreased, at higher stages in the Barrett's sequence. There was almost complete loss of RAR-gamma expression (relative expression level < or = 1) in a majority (70%) of the dysplasia and adenocarcinoma tissues. There were significant differences in RAR-alpha and RAR-gamma expression in histopathologically normal tissues in patients with cancer versus patients without cancer. RAR-beta expression levels were significantly elevated in adenocarcinoma versus normal esophagus tissues. The RAR expression profile was similar for cancers arising within the esophagus and for cancers arising at the gastroesophageal junction. CONCLUSIONS: RAR mRNA expression levels are significantly different in Barrett's tissues compared with normal esophagus tissues, and these levels are significantly different in Barrett's dysplasia and adenocarcinoma tissues compared with nondysplastic tissues. These results suggest that RAR mRNA levels may be useful biomarkers for this disease and that gastroesophageal junction adenocarcinomas are genetically similar to esophageal adenocarcinomas. These results also suggest that a cancer field is present in the esophagus in patients with cancer and that genetic alterations can precede histopathologic alterations in this disease.  相似文献   
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