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21.
S. H. Pross Y. Nakano S. McHugh R. Widen T. W. Klein H. Friedman 《Immunopharmacology and immunotoxicology》1992,14(3):675-687
Marijuana, and specifically its psychoactive component, THC, can up or down regulate lymphocyte proliferation in murine spleen cells depending in part on the method used to stimulate the cells. This study identifies a difference in THC induced disregulation using cells derived from two different secondary lymphoid organs, the spleen and the lymph node. It was found that THC treatment of mitogen (concanavalin A or phytohemagglutinin) stimulated cells derived from either organ resulted in suppression of the proliferative response. In contrast, spleen cells stimulated with anti-CD3 antibody and treated with low doses of THC displayed an enhanced proliferation whereas the response in lymph nodes did not change. The cell type involved with this THC immunoenhancement in spleen cells was found to be the Ly2 cell. Further differences in the THC modulation of Ly2 spleen cells as compared to lymph node cells were noted following stimulation with PHA. Proliferation of Ly2 cells of splenic origin was inhibited with low doses of THC whereas the Ly2 cells of lymph node origin were more resistant to this drug induced suppression. This study, therefore, demonstrates differences in the immunomodulatory capability of THC dependent upon the organ source of the lymphocytes. 相似文献
22.
PLASMA FOLLISTATIN CONCENTRATIONS INCREASE FOLLOWING LIPOPOLYSACCHARIDE ADMINISTRATION IN SHEEP 总被引:1,自引:0,他引:1
Rudi Klein Iain J. Clarke† Mark P. Hedger† David M. Robertson† 《Clinical and experimental pharmacology & physiology》1996,23(8):754-755
1. The effect of inflammation induced by lipopolysaccharide (LPS) injection on plasma follistatin (FS) concentrations was investigated. 2. Plasma FS and tumour necrosis factor-α concentrations increase following LPS administration in ewes. 3. The rise in FS is similar, but more sustained, to that previously observed after surgery. 4. These results indicate a possible functional link between FS, inflammation and the acute-phase response. 相似文献
23.
Acute appendicitis in the pregnant patient 总被引:6,自引:0,他引:6
Acute appendicitis is the most common surgical problem in pregnancy requiring emergent intervention. To establish a contemporary patient profile and formulate an effective management strategy, a retrospective review was conducted of 84 pregnant patients who underwent laparotomy with a preoperative diagnosis of acute appendicitis. Gestational stage at presentation included the first trimester in 27 patients (32%), the second trimester in 37 patients (44%), the third trimester in 13 patients (16%), and the puerperium in 7 patients (8%). Fifty-four patients (64%) had pathologically proven acute appendicitis; the incidence did not vary by trimester. Other intra-abdominal conditions were detected in 15 patients (18%). There were no significant differences between patients with positive and negative laparotomies (or among trimesters) regarding frequency of presenting symptoms and signs or laboratory results. Operation occurred within 24 hours of symptom onset in 19 of 54 (35%) instances of proven acute appendicitis. Perforation occurred in 23 of 54 patients (43%), all of whom had symptoms exceeding 24 hours (p less than 0.0005). Five instances of perinatal death and one case of extreme perinatal morbidity were associated with negative laparotomies; only one of these was attributed to operation itself. No adverse long-term maternal morbidity or mortality occurred. Wound infection developed in seven cases of acute appendicitis (six perforated) and two negative explorations. We conclude that (1) gestational physiologic changes obscure the accurate diagnosis of acute appendicitis; (2) the natural history of acute appendicitis is not affected by trimester of presentation; and (3) adverse sequelae of acute appendicitis are obviated by prompt operative exploration and prevention of appendiceal perforation. 相似文献
24.
Reaming versus non-reaming in medullary nailing: Interference with cortical circulation of the canine tibia 总被引:13,自引:2,他引:11
M. P. M. Klein B. A. Rahn R. Frigg S. Kessler S. M. Perren 《Archives of orthopaedic and trauma surgery》1990,109(6):314-316
Summary Medullary nails have only been used with reluctance in the treatment of open fractures since reaming interferes with the cortical circulation. The technique of interlocking offers the interesting possibility of inserting a relatively stiff nail which does not necessarily require reaming. The effects of reaming prior to nail insertion upon the cortical circulation was investigated in the canine tibia. Intravital staining with procion red was used to trace areas of disturbed circulation. Nail insertion without reaming provided clear advantages for the bone's blood supply, while reaming disturbed perfusion in two-thirds of the cortical area and regionally extended through the entire thickness of the cortex. The disturbance without reaming was limited to the inner layer of the cortex and involved only one-third of the cortical cross-section. 相似文献
25.
Extracorporeal membrane oxygenation for the circulatory support of children after repair of congenital heart disease 总被引:1,自引:0,他引:1
M D Klein K W Shaheen G C Whittlesey W W Pinsky E Arciniegas 《The Journal of thoracic and cardiovascular surgery》1990,100(4):498-505
We have treated 39 infants and children with congenital heart disease with extracorporeal membrane oxygenation during the past 5 years. Thirty-six were treated for low cardiac output or pulmonary vasoreactive crisis after repair of congenital heart defects. Twenty-two (61%) survived. Most patients were cannulated from the neck via the right internal jugular vein and the right common carotid artery. Six patients were cannulated from the chest, including three who had separate drainage of the left side of the heart with a left atrial cannula. Two of these patients survived and were the only survivors of the nine patients cannulated in the operating room because they could not be weaned from cardiopulmonary bypass after open cardiac operations. We also reviewed 312 patients (the predictor study series) having open cardiac operations before the availability of extracorporeal membrane oxygenation; 27 of these patients died. Data were collected at 1 and 8 hours postoperatively to determine if any parameters might predict early mortality. With these parameters used as criteria, patients who went on extracorporeal membrane oxygenation were as sick as those who died before extracorporeal membrane oxygenation was available. The most common complication was bleeding related to heparinization. The mean transfusion requirement in survivors was 1.50 +/- 1.13 ml/kg/hr, 5.63 +/- 7.0 ml/kg/hr in the nonsurvivors, and 7.46 +/- 8.29 ml/kg/hr in those cannulated in the operating room because they could not be weaned from bypass. Four children had intracranial hemorrhage, and two of them died. There was one late death. Nine of the 22 survivors are entirely normal. All survivors who do not have Down's syndrome are considered to have normal central nervous system function. We conclude that extracorporeal membrane oxygenation can improve survival in patients with both pulmonary artery hypertension and low cardiac output after operations for congenital heart disease. 相似文献
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28.
Judith D. DePue Elizabeth L. McQuaid Daphne Koinis-Mitchell Christopher Camillo Anthony Alario Robert B. Klein 《The Journal of asthma》2007,44(6):449-453
Over 3 years, 972 families participated in an after-school asthma program at their child's school. Parents and children attended concurrent 21/2 -hour workshops. Parents were 74% Latino; 45% non-English speaking, with 77% of children on Medicaid. Asthma symptoms were significantly reduced, from multiple times per week to less than once per week on average. Oral steroid use decreased to one third of baseline use. Hospital days decreased from 11% to 2%; emergency visits decreased 35% to 4%; and school days missed decreased 48% to 20%. This program has now become sustainable with both private and Medicaid insurance coverage. 相似文献
29.
30.
Joseph Cofrancesco Nina Shah Khalil G Ghanem Adrian S Dobs Robert S Klein Kenneth Mayer Paula Schuman David Vlahov Anne M Rompalo 《Gynecological endocrinology》2006,22(5):244-251
Drug use and HIV infection may affect sex hormone levels in women. One hundred and ninety-six women with and without a history of illicit drug use (50 HIV-negative and 148 HIV-infected), with regular menses, who never used antiretrovirals, were evaluated. Luteinizing hormone levels were significantly higher in women with a CD4 cell count <200/microl (p < 0.002). Current methadone use was associated with lower levels of total testosterone (p = 0.03) and higher levels of prolactin (p = 0.002); mean estradiol levels were 43% lower in women who used intravenous drugs (p < 0.001). Alcohol and crack cocaine use was not associated with sex hormone levels. Age, race, body mass index and degree of HIV immunosuppression were also associated with differences in sex hormone levels. 相似文献