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71.
Childhood obesity.   总被引:7,自引:0,他引:7  
Childhood obesity has become one of the more alarming nutritional problems plaguing the American population, with estimates as high as 25% of all children being obese. Aside from obesity's associated risks, there are psychosocial and emotional burdens carried by obese children as well. Clinicians are encountering many of these children in their clinics everyday for other reasons and yet are failing to address the issue of obesity. The problem is not so much that physicians are not recognizing it, but rather that they are ignoring it, especially if the parent or child is unaware that there is a problem. Unfortunately, much controversy exists regarding the treatment of childhood obesity. This article attempts to sort through the myriad issues surrounding childhood obesity and to dispel some of the rumors and myths surrounding this subject.  相似文献   
72.
The effect of the 21-aminosteroid U74006F on neurologic recovery after a spinal cord compression trauma was investigated in rats. The compression was induced by a blocking weight technique, in which a 35 g (moderate injury) or a 50 g (severe injury) weight was applied for 5 minutes to an 11 mm2 plate over the midthoracic spinal cord. One hour after trauma, the severely injured animals were treated either with U74006F, 3 mg/kg, methylprednisolone, 30 mg/kg, or vehicle, whereas the moderately injured animals received U74006F, 3 mg/kg or vehicle. Neurologic hind limb function was evaluated by the inclined plane technique. On day 1 after trauma, subtotal paraparesis occurred in the 35 g group treated with vehicle (31 +/- 1 degrees, mean +/- SEM) on the inclined plane vs 64 +/- 1 degrees before trauma) and complete paraplegia in the 50 g group (22 +/- 1 degrees). Treatment with U74006F resulted in less hind limb weakness in the 35 g group (42 +/- 2 degrees) but had no beneficial effect in the 50 g group (25 +/- 2 degrees). Neurologic function gradually improved in the 35 g groups over the 9-day observation period. However, those animals treated with U74006F were significantly better over the entire period. In the 50 g group, no recovery from paraplegia was noted over the 4 day observation period in any of the three groups. These results suggest that after weight-induced spinal cord trauma, U74006F is associated with improved neurologic function in moderately injured, but not severely injured animals.  相似文献   
73.
74.
Out of a cohort of 1200 apprentices in Switzerland, 781 boys and 417 girls completed a questionnaire on their perceived health and health problems in their selected apprenticeship. Each participant was interviewed afterwards by the school nurses in three state-owned professional schools where the apprentices attended their classes. Ninety-five per cent of the respondents enjoyed excellent health, 28 cases had nervous system or psychological problems, 17 cases had problems of a locomotor nature, 12 subjects had gastrointestinal or endocrinological symptoms, and there was one with a past history of a malignant disease. Twelve cases also had respiratory symptoms or diagnoses. One hundred and nineteen apprentices reported that they had been troubled by the workplace. Exposure to solvents, chemicals in general, dust, smoke and noise were often mentioned as causes. Thirty-eight of them had contacted their family physician in connection with these problems. The cohort had experienced, mostly during their first year, 191 cases of accident necessitating medical care. Cuts, shocks and falls were the most common occurrences. Meat cutters and butchers had the highest frequency of accidents. Near-accidents had been experienced so far by 46 per cent of the respondents. At the interviews, school nurses provided counsel and intervened in flagrant cases of occupational risks. It seems that an ordinary medical certificate does not predict accident-proneness or possible medical problems, while in-school health programmes could provide rapid intervention and support.  相似文献   
75.
Gastroesophageal reflux. Don't forget to ask about heartburn   总被引:2,自引:0,他引:2  
D O Castell  A Holtz 《Postgraduate medicine》1989,86(5):141-4, 147-8
At least 13% of the US adult population have chronic heartburn, and unknown percentages of others have related symptoms of gastroesophageal reflux disease. Studies show that most people with symptoms of reflux self-medicate and do not seek medical advice. Also, they fail to mention these symptoms when visiting their physician for other conditions. Therefore, the importance of thorough history taking cannot be overstated, and it may be prudent for primary care physicians to question all patients routinely about reflux symptoms.  相似文献   
76.
LR Petersen  ; LS Doll 《Transfusion》1991,31(8):698-703
Transmission of human immunodeficiency virus type 1 (HIV-1) by homologous blood transfusion in the United States (US) is minimized by the deferral of potential donors who are at risk for HIV-1 infection and by the screening of all donations for HIV-1 antibody. HIV-1-seropositive donors at 20 blood centers were studied for information to be used in evaluating the safety of the US blood supply and making recommendations to increase that safety. From June 1988 to August 1989, 829 (0.04%) of 2,192,000 donors were found to be seropositive; 512 were interviewed. Of 388 seropositive men, 56 percent had had sex with men, 10 percent had used drugs intravenously, 8 percent had had sex with intravenous drug users, and 27 percent had no identified risk. Of 124 seropositive women, 58 percent had had sex with men at risk for HIV (81% of whom used drugs intravenously), 5 percent had used drugs intravenously, and 41 percent had no identified risk. Racial and ethnic minorities made up 68 percent of seropositive donors (black, 38%; Hispanic, 30%) and approximately 14 percent of all donors. The 157 persons with no identified risk had demographic characteristics and serologic test results for syphilis and hepatitis B that were more similar to those of HIV-1-seropositive donors with recognized risk than to those of seronegative donors. Three health care worker-blood donors (from an estimated 93,100 health care worker-donors) had infection that was probably acquired occupationally.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
77.
BACKGROUND: Chagas' disease is transmitted to man either by the bite of insects harboring Trypanosoma cruzi or by the transfusion of blood from infected donors. The conventional serologic testing as presently used in blood banks in South America is unsatisfactory, because of a high number of inconclusive and false-positive results. Other methods such as polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA) with recombinant antigens have been proposed, but inherent difficulties have so far precluded their adoption in the large-scale screening required by blood banks. STUDY DESIGN AND METHODS: A highly sensitive and specific chemiluminescent ELISA using a purified trypomastigote glycoconjugate antigen and a complex epimastigote antigen was devised for the diagnosis of active T. cruzi infection. RESULTS: Chemiluminescent ELISA was 100-percent sensitive in the diagnosis of 100 cases of confirmed Chagas' disease. Inconclusive results and false-positive reactions were eliminated in a panel of 115 sera.The specificity of the chemiluminescent ELISA was 100 percent with a purified trypomastigote glycoconjugate antigen and 99.7 percent with a complex epimastigote antigen when applied to 1000 normal human sera and 288 heterologous sera from patients with other infections, including leishmaniasis, and vaccinated individuals. CONCLUSION: The chemiluminescent ELISAs provide a test that is highly sensitive (purified trypomastigote glycoconjugate and complex epimastigote antigens) and specific (purified trypomastigote glycoconjugate antigen) for Chagas' disease diagnosis. It can be used in blood bank screening and to monitor the treatment of patients undergoing chemotherapy.  相似文献   
78.
Prior studies established that ultraviolet-B light (UVB) irradiation of platelet concentrates (PCs) at appropriate doses can eliminate the mixed lymphocyte culture-stimulating and -responding capacity of lymphocytes in the PCs without adversely affecting in vitro platelet function. The in vivo recovery and survival and in vitro characteristics of UVB-irradiated platelets were investigated in paired studies. PCs were stored for 1 day and then exposed to UVB. Platelet recovery, survival, and function were comparable to those of nonirradiated platelets. Recovery and survival of platelets stored for 5 days before UVB exposure were decreased relative to controls, although they were considered clinically acceptable. Paired transfusion studies were also performed in seven thrombocytopenic patients by using platelets obtained by apheresis. Comparable posttransfusion platelet increments and bleeding time corrections were obtained with both irradiated and control (nonirradiated) platelets. It can be concluded that platelets survive and function relatively normally in vivo after UVB irradiation sufficient to abolish lymphocyte reactivity in mixed lymphocyte culture. Long-term studies of UVB-irradiated PCs are needed to assess their potential in reducing recipient alloimmunization.  相似文献   
79.
BACKGROUND: Testing for antibody to hepatitis B core antigen (anti-HBc) as a surrogate for hepatitis C viremia is no longer needed for blood donor screening. Currently, the important question is how much its use supplements hepatitis B surface antigen (HBsAg) donor screening in preventing transfusion-transmitted hepatitis B virus (HBV) infection. STUDY DESIGN AND METHODS: In a study conducted in the 1970s, 64 blood donors were associated with 15 cases of HBV (1.0%) in 1533 transfusion recipients. Sera from 61 donors at donation and 29 follow-up visits were available for present-day assays for HBsAg, HBV DNA, anti-HBc, and antibody to HBsAg (anti-HBs). RESULTS: HBsAg was found in four previously negative blood donors; HBV DNA was limited to three of these four. Anti-HBc was detected in six HBsAg-negative donors. Two other donors were negative in all assays at donation, but positive for anti- HBc and anti-HBs 2 to 4 months later. The remaining donors were negative for all HBV markers, which left five recipient cases unexplained. No HBV transmission was observed when anti-HBs sample-to- negative control values were > or = 10. CONCLUSION: Some 33 to 50 percent of cases of hepatitis B that could be transmitted by transfusion of blood from HBsAg-negative donors are prevented by anti- HBc screening. Anti-HBc-positive donors unequivocally positive for anti- HBs should be considered noninfectious for HBV and should be allowed to donate. Anti-HBc screening of paid plasmapheresis donors, supplemented by anti-HBs testing, would reduce the amount of HBV to be processed by virus inactivation and increase the content of anti-HBs in plasma pools.  相似文献   
80.
We have described a 28-year-old diabetic woman who had necrotizing fasciitis of the perineum three years after receiving a living related renal transplant. The diagnosis of necrotizing fasciitis was made early and she was referred to a tertiary care center where she received radical perineal debridement and aggressive medical and surgical follow-up. Necrotizing fasciitis in a transplant patient is rare; review of the literature shows few cases and no survivors. Our patient has returned to a normal life despite continuation of all immunosuppressive therapy throughout the entire hospital course. In addition, she had a good cosmetic result despite the large necrotic perineal infection. Her survival can be attributed to early diagnosis and referral, immediate and extensive debridement, and aggressive protein replacement.  相似文献   
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