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51.
Late onset postpartum thrombocytosis in preeclampsia 总被引:2,自引:0,他引:2
BACKGROUND: During pregnancy, changes in blood coagulation and fibrinolysis create a hypercoagulable state. In the puerperium this thrombogenicity is even higher, and the chance of developing thromboembolism is 3-5 times higher in this period than during pregnancy. In preeclampsia, platelets are activated and play a substantial role in the pathogenesis of the disease. Systematic information on longitudinal changes in platelet number and size postpartum after normotensive and preeclamptic pregnancies is not available. METHODS: We measured platelet number, mean platelet volume and the median volume of the 20% largest platelets in eleven preeclamptic and eleven normotensive pregnant women matched for mode of delivery. The blood samples were taken antepartum and every 2-3 days in the postpartum period until the platelet count decreased/normalized. RESULTS: In the preeclamptic group, the platelet count increased significantly from 240x10(9)/l antepartum to 621x10(9)/l on day 6-14 postpartum (p<0.01). In the control group, the platelet count increased from 214x10(9)/l antepartum to 251x10(9)/l on day 2-5 (p<0.01) and 351x10(9)/l on day 6-14 postpartum (p<0.01). The platelet count was significantly higher in the preeclamptic than in the control group 6-14 days postpartum (p<0.01). Antepartum, mean platelet volume and the median of the 20% largest platelets were significantly higher in the preeclamptic than in the control group. CONCLUSION: The platelet count is significantly increased postpartum both after normotensive, and 2-3 fold more after preeclamptic pregnancies. The time to peak values is between 6-14 days, usually at a time when patients are discharged from hospital. 相似文献
52.
Single-strand breaks in DNA of various organs of mice induced by styrene and styrene oxide 总被引:1,自引:0,他引:1
Styrene and its metabolite styrene oxide were given i.p. to mice. The induction of single-strand breaks (SSB) in DNA was studied with the DNA unwinding technique. The level of SSB in kidney-DNA was a linear function of the dose for both substances. Styrene and styrene oxide induced an increase in the level of SSB in DNA of kidney, liver, lung, testis and brain 1 h after administration. After 24 h the damage remained on an enhanced level in liver, lung and testis after styrene oxide administration and in all organs except liver after styrene administration. 相似文献
53.
Isolated rat liver parenchymal cells incubated with anaesthetic concentrations of diethyl ether1 were shown to produce acetaldehyde and ethanol in a dose dependent manner. The acetaldehyde and ethanol production from ether was stimulated in hepatocytes derived from phenobarbital treated rats and could be only partially inhibited by 4-methyl pyrazole (250 μM). The present results support previous suggestions that diethyl ether is metabolized by an inducible microsomal enzyme system which cleaves diethyl ether in a reaction analogous to the well known O-dealkylation reactions. 相似文献
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55.
Hursti TJ Börjeson S Hellström PM Avall-Lundqvist E Stock S Steineck G Peterson C 《Scandinavian journal of gastroenterology》2005,40(6):654-661
OBJECTIVE: The introduction of 5-HT3 receptor antagonists greatly reduced the problems associated with nausea and vomiting immediately after cancer chemotherapy. However, delayed nausea and vomiting is still a major problem and the underlying mechanism is obscure. MATERIAL AND METHODS: We studied the effect of cisplatin-containing combination chemotherapy in 14 ovarian cancer patients on the levels of gastrin and a panel of other hormones as well as glucose and prostaglandin F2a. Blood samples were obtained once daily in the morning before chemotherapy and for 4 days after chemotherapy. RESULTS: Concentrations of many hormones including gastrin were generally high. A pronounced increase in plasma insulin levels occurred on the day after chemotherapy accompanied by a modest increase in plasma glucose concentrations. Minor increases were observed for gastrin, oxytocin and prostaglandin F2a. In contrast, a transient decrease after chemotherapy was observed for motilin. Plasma cortisol decreased markedly after chemotherapy as expected since betamethasone was given as an antiemetic prophylaxis. Certain trends concerning the relationship between some hormones and nausea and vomiting were noted. A high plasma gastrin concentration before chemotherapy was related to delayed vomiting. Relative day-to-day variability of cholecystokinin tended to correlate positively with delayed nausea, whereas an inverse relationship was observed for gastrin variability. CONCLUSIONS: Changes in hormone plasma levels were found but only few could be distinguished as possible mediators of delayed nausea and vomiting. 相似文献
56.
The purpose of this study was to design an instrument for the optimal guiding of osseointegrated implants intraoperatively to achieve parallelism or desired angulations. Seven patients (4 males and 3 females) were enrolled in the investigation. They ranged in age from 44 to 61 years. Using an instrument designed by the senior author that permitted optimal guiding of the osteotomy instruments (33 Osteofix Oy, Oulu, Finland) we placed in these patients, root form, single stage implants. The difference in angulations between the first and the remaining implants was measured using the abutment replicas on the working models. It was found that the mean deviation angle between the first and the adjacent implant replicas was 2.2 degrees (SD = 0.4 degrees). The largest deviation angles were 2.3 degrees (SD = 0.5 degrees) and 3.1 degrees (SD = 0.8 degrees). The study indicated that the instrument had been designed in a functional manner and that all implants in such relationships can be inserted into their desired positions, either parallel to one another or with the desired angle for the planned prostheses. 相似文献
57.
58.
Hjortland GO Garman-Vik SS Juell S Olsen OE Hirschberg H Fodstad O Engebraaten O 《Journal of neurosurgery》2004,100(2):320-327
OBJECT: The aim of this study was to target immunotoxin treatment to the high-molecular-weight melanoma-associated antigen (HMW-MAA) and thereby examine any changes in the survival of immunodeficient rats with human glioblastoma multiforme (GBM). METHODS: To target treatment specifically to human glioma cells, Pseudomonas exotoxin A (PE) was conjugated to the 9.2.27 antibody, which recognizes the HMW-MAA. Treatment of the antigen-positive glioma cell line U87MG with the resulting 9.2.27-PE caused cytotoxicity with a median inhibitory concentration of 1 ng/ml. Intratumoral 9.2.27-PE treatment of intracranial U87MG tumors in nude rats prolonged the survival of these animals by 43% compared with controls. In additional studies on the use of this targeted treatment, the authors precultured freshly dissected glioblastoma multiforme (GBM) biopsy tissue for 1 to 2 weeks. Inoculation of this tissue into the rat brain resulted in diffuse infiltrative gliomas. The markers glial fibrillary acidic protein and S100 protein were found to be expressed in the original biopsy specimens, as well as in the glioma xenografts in nude rat brains. Intratumoral immunotoxin treatment of such established tumors with 9.2.27-PE was effective and prolonged survival time from 30% to as high as 90% in animals with tumors originating from four different GBM specimens. CONCLUSIONS: Targeted treatment of highly invasive GBMs proved effective, and these results emphasize the clinical relevance of this antigen as a target molecule for immunotoxin treatment of human GBMs. 相似文献
59.
Do the results of the process indicators in the Norwegian Breast Cancer Screening Program predict future mortality reduction from breast cancer? 总被引:1,自引:0,他引:1
Continuous emphases of quality control are required to achieve reduction in mortality from breast cancer as a consequence of breast cancer screening. Results of the process indicators in the first 6 years in 4 counties in the Norwegian Breast Cancer Screening Program are evaluated and will be presented. Data from women who had their initial (n=173 402) and subsequent (n=220 058) screening provide the basis for the analysis. The breast cancer detection ratio was 3.2 the expected incidence (based on the incidence before the screening started, 1991-1995) among the initially screened women, decreasing to 2.3 among the subsequently screened. The ratio of interval cancer among the initially screened was 0.25 and 0.72 of the expected incidence, 0-12 and 13-23 months after screening, respectively. For those subsequently screened the proportions were 0.22 and 0.64, respectively. More than 50% of the invasive tumors were less than 15 mm in size, and more than 75% were lymph node negative, among both the initially and subsequently screened. The process indicators achieved in the NBCSP are promising as regards future mortality reduction. The incidence of interval cancer 13-24 months after screening is higher than recommended in the European guidelines. 相似文献
60.