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81.
The effect of circumstances and/or organs on the grade of cancer growth and malignancy was studied, using hereditarily identical VX2 cancer. VX2 cancer cells, 10(6) cells/0.1 approximately 0.2 ml, were injected into the liver, portal vein, stomach- and colon-walls of Japanese white rabbits. Each of the experimental groups consisted of 14, 12, 19 and 24 animals, and 3 or 4 animals of each groups were sacrificed 7, 14, 21 and 28 days after the implantation. All the animals of portal vein and liver groups died of cancer within 3 and 4 weeks respectively. However, all the animals of stomach and colon groups survived during 4 weeks. Although cancer volume doubling time was not calculated in portal group because of the multiple and diffuse tumor-formation, the time was 2.6 days in liver, 4.3 days in colon and 5.9 days in stomach groups in which a single tumor developed. Lymphatic and/or hematogenous metastases were found at the same time after the implantation as vascular invasion occurred. Metastases were confirmed in 100% in liver group and 40% in portal group 2 weeks after the implantation, and 80% and 50% in colon and stomach groups respectively 4 weeks after the implantation. The results suggested that hereditarily identical VX2 cancer was variable in the different organs and circumstances, and that the growing circumstances strongly affected the cancer malignancy. It was also suggested that the malignancy was correlated with the growth rate and the time of metastasis of cancer.  相似文献   
82.
Using 655 peripheral blood samples from normal individuals and patients, we evaluated the relationship between the measurements of red blood cell (RBC) and white blood cell (WBC) through the Hematrak 590 (Hematrak) and the generated flag systems in the Technicon H-2 (H-2). 1) Among the 12 VAR (Variation) flag positive samples in H-2, 10 samples were obtained from the patients receiving blood transfusions. The samples with high values of HDW (Hemoglobin distribution width) in H-2 seemed to have hypochromatic and polychromatic changes in RBC. 2) Hematrak is likely to be more sensitive than H-2 in discovering atypical lymphocytes (AL). When AL counts in Hematrak were over 5 or 6% of WBC, these results were coincident with ATYP flag positive in H-2. 3) In our examinations, when %Blast in H-2 was over 4%, BLASTS flag always generated positively. We think that H-2 is a tool with high reproducibility for the detection of the blast-like abnormal cells. 4) We evaluated the results of WBC differential count by the three methods of H-2, Hematrak and manual procedures in the peripheral blood samples from normal individuals. We recognized close correlations in neutrophils, lymphocytes and eosinophils (coefficients of correlation = 0.826-0.911), and relatively close ones in monocytes (r = 0.280-0.562), but no correlations in basophils (r = 0.106-0.281). To comprehend the pathophysiological states of the various diseases hematologically, it is necessary to understand the characteristics of the different measurement principles between the two instruments (H-2 and Hematrak).  相似文献   
83.
This article discusses autoimmune reactions and the numerous mechanisms by which an autoimmune response may be initiated, including genetic factors, T-cell bypass mechanisms, and idiotypes. Human autoimmune diseases are classified into three main groups, ie, organ-specific, non-organ specific, and disorders with non-organ-specific autoantibodies with lesions restricted to one or a few organs, that are examined in detail. General laboratory tests and interpretation of results in relation to state or treatment of the particular disease, age and sex of the patient, and the sensitivity of the test system used are reviewed.  相似文献   
84.
Intracellular recordings of electrical activity were made from circular smooth muscle cells in small segments of tissue isolated from the guinea-pig stomach antrum. Every cell that was impaled exhibited a rhythmic generation of slow potentials. Experiments were carried out to test the effects of three different concentrations (1, 10 and 100 nM) of phorbol 12, 13-dibutyrate (PDBu) on these slow potentials and on the responses produced by acetylcholine (ACh), in the presence of nifedipine and N(omega)-nitro-L-arginine (nitroarginine), known inhibitors of L-type Ca-channels and nitric oxide synthase, respectively. The resting membrane potential was -62 +/- 7 mV, while the frequency and amplitude of the slow potentials were 1.6 +/- 0.1 cycle per min (cpm) and 33 +/- 1 mV, respectively. Application of 1 nM PDBu increased the frequency of slow potentials, with no significant change in the membrane potential and amplitude of slow potentials. At a concentration of 100 nM, PDBu depolarized the membrane by about 6 mV, and either decreased the amplitude and frequency of the slow potentials or abolished them. The amplitude and frequency of the slow potentials were not significantly changed in the presence of 10 nM PDBu. In the presence of chelerythrine (1-2 microM), a known inhibitor of protein kinase C (PKC), the increase in frequency of slow potentials by 1 nM PDBu and depolarization produced by 100 nM PDBu were not elicited. The increase in frequency of slow potentials by 100 nM ACh was inhibited by PDBu, in a concentration-dependent manner, and ACh-responses were abolished in the presence of 100 nM PDBu. These results indicate that PDBu has dual actions on the spontaneous activity of antral circular muscle, with low concentrations increasing and high concentrations inhibiting the frequency of the slow potentials. The former may be produced by activation of protein kinase C (PKC). As the ACh-induced excitation of slow potentials is inhibited by PDBu, a possible causal relationship between the inhibition and over-activation of PKC is considered.  相似文献   
85.
Tissue factor in neutrophils: yes   总被引:4,自引:1,他引:3  
  相似文献   
86.
Subdural hygroma is a frequent delayed complication of head trauma. Most hygromas are clinically 'silent' and a few cases have shown slow deterioration in the chronic stage. We report a case of subdural hygroma showing unique radiological findings and rapid deterioration. A 74-years-old female presented with a mild headache and consciousness disturbance after head injury. Computed tomography showed a midline shift as a result of two components piling up in the subdural space; the outer components showed low density, the inner components high density. Magnetic resonance imaging demonstrated that these two subdural components were subdural hygroma and subarachnoid hematoma. Simple burr hole irrigation, rather than large craniotomy, was thought to be more appropriate treatment to reduce the mass effect. Simple burr hole irrigation was performed to remove the subdural hygroma and the patient showed an excellent recovery. Careful examination of the radiological findings prevented an unnecessary procedure in this case. A possible mechanism of this phenomenon is discussed.  相似文献   
87.
Study Objective: To compare the volatile anesthetic sevoflurane with halothane, enfurane, and isof urane on the uptake and biotransformation in humans.

Design: Prospective pharmacokinetic study of sevofurane administration in human subjects.

Setting: Inpatient surgery clinic at a university medical center.

Patients: Thirty-two Japanese patients, free of systemic diseases, undergoing minor elective surgery with endotracheal general anesthesia.

Interventions: The patients were assigned randomly to one of four groups: halothane, enflurane, isofurane, or sevofurane. One of the four volatile anesthetics being investigated [equivalent to 1.1 minimum alveolar concentration (MAC): halothane, 0.85%; enfurane, 1.85%; isofurane, 1.27%; and sevofurane, 1.88%; in inspired concentrations throughout the first hour of anesthesia] was administered for 60 minutes.

Measurements and Main Results: In all patients, serum and urinary fluoride concentrations were measured. The concentrations of all gases were measured separately with a mass spectrometer. The cumulative uptake of each anesthetic agent during a certain period was calculated as an integration of the uptake rate per minute. The results for one-hour inhalation of sevofurane (1.1 MAC) showed an uptake (corrected for body surface area and MAC) of 490 ml/m2/MAC and estimated degradation rate of 3.3%. For purposes of comparison, similar studies of halothane (uptake, 653 ml/m2/MAC; degradation rate 15.7%), enfurane (1150 ml/m2/MAC; 1.3%), and isofurane (439 ml/m2/MAC; 0.6%) were also conducted. Sevofurane had a peak serum inorganic fluoride concentration of 19.3 μmol/L, and no abnormality in hepatic or renal functions was observed in any of the subjects during the two weeks postoperatively.

Conclusions: Accurate determinations of uptake and degradation rate for sevoflurane and three other volatile anesthetics in Japanese patients were obtained. These findings have established that, despite its relatively large MAC *1.71%), sevoflurane has a small uptake due to its low solubility. However, the degradation rade was shown to be as high as 3.3%, resulting in a higher serum fluoride concentration than seen after administration of isoflurane, halothane, and (possibly) enflurane.  相似文献   

88.
Giant aneurysms are the most serious issue of patients with Kawasaki disease (KD). To clarify risk factors for these giant aneurysms, we conducted a matched case-control study. Among the patients reported in nationwide surveys, 117 patients with giant aneurysms had an unequivocal new diagnosis and presented at the treatment center within 9 d of illness. We obtained clinical information on admission of about 69 patients (case) from the treatment centers. One control was selected for each case, an age- and sex-matched patient without coronary involvement, reported from the same treatment center at about the same time as the case, and we obtained the same clinical information about controls. Fourteen variables were analysed with a conditional logistic regression model: body temperature, hematocrit, hemoglobin, numbers of leukocyte and platelets, concentrations of serum albumin, globulin, total cholesterol, sodium, potassium and chloride, erythrocyte sedimentation rate, C-reactive protein and alanine aminotransferase activity. After adjustment for age, duration of illness before admission and use of intravenous gamma globulin therapy, C-reactive protein [odds ratio (OR) = 1.142, 95% confidence interval (CI) 1.054-1.237], alanine aminotransferase activity (OR = 1.008, 95% CI 1.002-1.014), serum sodium concentration (OR = 0.877, 95% CI 0.770-0.999) and serum potassium concentration (OR = 0.319, 95% CI 0.124-0.822) were significantly related to the risk for giant aneurysms. Further analyses with these four explanatory variables revealed that C-reactive protein (OR = 1.159, 95% CI 1.022-1.315) and serum potassium concentration (OR = 0.222, 95% CI 0.052-0.948) met the significant level. Thus, the values for serum C-reactive protein and potassium are independent risk factors for the development of the giant aneurysms of Kawasaki disease.  相似文献   
89.
The same iron pot in which their father had boiled lead with mercury (from a glass thermometer) for the purpose of alchemy, was also used for cooking in the kitchen. Although his wife had died of mercury poisoning, and his 14-year-old and 11-year-old daughters were found to excrete 322 and 455 micrograms/l mercury in the urine, respectively, (1-10 micrograms/l in controls), he stubbornly refused to give permission for them to be examined further. Nine months later, the daughters were permitted to be sent to our clinical ward. While the blood level of mercury had already come down to near normal, its excessive deposition in hair, kidneys and other parts of the body as well as its excessive urinary excretion, were still persistent (beyond tenfold the normal). According to our measurement values, mercury ranged from 14 to 49 micrograms/g in every 1-cm-piece of 10 cm hair of the elder sister, and ranged from 21 to 85 micrograms/g in 14 cm hair from the younger sister. About a 75% decrease in mercury deposition was estimated during these 9 months, based on the speculation of 1.5 cm/month hair-lengthening.  相似文献   
90.
The purpose of this study was to investigate the cellular composition of peritoneal fluid during post-surgical re-epithelialization and to determine the metabolism of arachidonic acid by these cells. Rabbits underwent a midline laparotomy followed by abrasion of the broad ligament. The presence of adhesions was graded and the peritoneal exudative cells collected up to 14 days thereafter. Ascitic fluid and cells were separated by centrifugation and the cellular percipitate incubated with [14C]arachidonic acid. The aliquot was separated by silica Gel G thin-layer chromatography and the specific radioactivity of each strip determined. To evaluate the reformation of adhesions 14 days after the first abrasion, rabbits underwent reabrasion of the same area and the pattern of arachidonic acid metabolism by the ascites cells was similarly evaluated. Six hours after the abrasion, PMNs comprised 87.5% of the peritoneal exudative cells (total 0.03 X 10(7) cells/rabbit). On Day 3, the total cell number increased to 2.92 X 10(7), 97.6% of which were large mononuclear cells. No significant change in the type of distribution of adhesions was evident from 6 hr through Day 2. After Day 7, the total number of adhesions was minimal; however, those that were present were primarily severe. The second-look evaluation of adhesion formation was not found to be consistent prior to the 7th postoperative day, since many filmy bands present prior to that time were not present later. The in vitro formation of 5-HETE by these cells increased from 6 hr through Day 11. Production of di-HETE increased beginning Day 3 and maintained high steady state levels thereafter.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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