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101.
Two dimensional electrophoresis is a technique whereby protein sources are organized by molecular weight and electrical charge on a polyacrylamide gel. To detect changes that may be associated with the onset of parturition, we compared electrophoresis patterns of mononuclear cell proteins and plasma proteins before and during active labor. Mononuclear cells and plasma were obtained from 5 pregnant volunteers. It appears that A-1 apolipoprotein, identified by Western Blot analysis, is increased in mononuclear cells during active labor. Conversely, a decrease in the concentration of A-1 apolipoprotein was seen in plasma during parturition. These "normal" protein patterns can now be compared with those observed in pathologic conditions including preterm labor and may allow early detection of disease by protein abnormalities before clinical signs and symptoms develop.  相似文献   
102.
Spontaneous portosystemic shunts are commonly found in cirrhotic patients. Not yet established is their role after orthotopic liver transplantation (OLTx), especially when an increase in portal pressure develops, as during early acute rejection. In this study, 34 cirrhotic patients in a series of 70 OLTx are considered. Each patient had preoperative angiographic assessment, and, in 21 (62%), large spontaneous portosystemic shunts were evident. In 12 cases the shunts were not affected by the surgical procedure and were present during the postoperative period; in 9 the hepatectomy itself involved interruption of the shunts. The patient population was divided into two groups: patients with postoperative shunts (n=12) and those without (n=22). The two groups were similar in age, sex, Child's stage, transplantation variables, and number and grade of rejection episodes. However, mean transaminases (AST) values in the first 2 weeks were significantly higher levels in shunt versus nonshunt patients (421±335 vs 183±126; P<0.025), and this was even more evident when rejection occurred (626±375 vs 195±129; P<0.001). Furthermore, during an acute rejection reaction, three cases showed a true steal phenomenon through the large reopened shunts with ischemic damage to the grafts. The data indicate a possible detrimental effect of the spontaneous shunts on graft perfusion and suggest the prophylactic surgical interruption of the residual shunts during the transplantation.  相似文献   
103.
OBJECTIVE: To assess the justification for the routine use of investigations in the diagnosis of bacterial causes of sore throat. DATA SOURCES: The literature from 1945 to 1990 was systematically screened to identify studies that addressed diagnosis of bacterial infection and the efficacy of antibiotics in sore throat, using the key-words "pharyngitis" and "tonsillitis". RESULTS: Difficulties were identified with clinical methods and investigations that identify streptococcal infections. The practice of throat-swab culture--the "gold standard"--appears to have developed as a strategy to protect patients from acute rheumatic fever. However, this method may be limited in its usefulness for protection against acute rheumatic fever because: (i) in many cases in which the streptococcus is isolated from symptomatic patients there is no serological evidence of infection; (ii) there are very high asymptomatic carrier rates of the streptococcus; (iii) even after adequate treatment with penicillin there are high bacteriological failure rates; and (iv) those organisms that can be isolated from the mucosal surface are a poor representation of organisms lying deep in the tissues. Evaluation of other diagnostic techniques such as Gram's stain and rapid antigen testing, as well as decision analysis, has also been hampered by the difficulties encountered with use of this inadequate gold standard. CONCLUSION: There is little indication from the literature that any routine system of identifying bacterial causes of sore throat is helpful to the clinician.  相似文献   
104.
Arthroscopic treatment of anterolateral impingement of the ankle   总被引:6,自引:0,他引:6  
We studied 31 patients (17 females, 14 males; average age, 34) with more than 2 years of followup who had chronic anterolateral ankle pain following inversion injury. All had failed to respond to at least 2 months of conservative treatment and had negative stress radiographs to rule out instability. On physical examination, tenderness was localized to the anterolateral corner of the talar dome. Magnetic resonance imaging was the most useful diagnostic screening test, showing synovial thickening consistent with impingement in the anterolateral gutter. At an average of 24 months after injury, all patients underwent ankle arthroscopy, which showed proliferative synovitis and fibrotic scar tissue in the lateral gutter, often with associated chondromalacia of the talus. Operative arthroscopic treatment consisted of partial synovectomy with debridement of scar tissue from the lateral gutter. Postoperatively, patients walked with crutches allowing weightbearing as tolerated. Average return to sports was 6 weeks. Histopathologic analysis performed on the resected tissue showed synovial changes consistent with chronic inflammation. Results of treatment after at least 2 year followup were 15 excellent, 11 good, 4 fair, and 1 poor. Since there are several distinct causes of chronic ankle pain, we prefer to call this problem "anterolateral impingement of the ankle" and believe the term "chronic sprain pain" should be discarded.  相似文献   
105.
A cumulative psychiatric case register was utilized to examine patterns of psychopathology in 1,334 adolescent patients. Consistent with studies of adult patients, seriousness of disorder was weighted toward being seen in an inpatient rather than outpatient settling; schizophrenia and personality disorder were relatively more common amoung lower-class patients and neurosis and situational disorder among middle- and upper-class patients; neurosis was more commonly diagnosed among female patients, and personality disorder more commonly diagnosed among males. A ten-year follow-up revealed 54.1% reasonable diagnostic stability on subsequent contacts and 62.2% complete subsequent agreement among patients originally diagnosed as schizophrenic. Aspects of the data demonstrate continuity in adolescent and adult psychopathology, the mythical nature of "normative adolescent turmoil," and what appears to be excesive use of situational disorder in diagnosing adolescent patients.  相似文献   
106.
The results of studies of the opiate antagonist Naltrexone (NLTX) in the treatment of self-injurious behavior (SIB) in various psychiatric populations have been equivocal. The majority of studies has relied on small samples, many of which lacked scientific rigor and none of which occurred in a nursing facility. The present study investigates the use of NLTX on a patient with severe SIB who resides in a nursing facility. The patient is a 38-year-old male with a history of heavy drug and alcohol abuse. He has been in either a state hospital or nursing facility since age 21. The patient overdosed on alcohol and drugs in 1990, which led to a prolonged coma with organic brain damage.  相似文献   
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BACKGROUND: Platelet-activating factor (PAF) is a phospholipid mediator of inflammation which has been implicated in rejection. The interaction of anti-alpha-galactosyl natural antibodies (anti-alpha gal Abs) with endothelial cells is the initial step for the development of xenograft rejection. In our study, we stimulated porcine aortic endothelial cells (PAEC) with anti-alpha gal IgG to investigate the synthesis of PAF from PAEC and its biological consequences. METHODS AND RESULTS: PAF was extracted and chromatographically purified from cultured PAEC stimulated with baboon anti-alpha gal Abs. The Abs induced a dose-dependent synthesis of PAF peaking after 30 min of incubation, and decreasing thereafter. Concomitant cell shape change, motility, and cytoskeleton redistribution were observed. These events were prevented by addition of a panel of PAF-receptor antagonists. An SV40 T-large antigen-immortalized PAEC line was engineered to express PAF acetyl-hydrolase (PAF-AH) cDNA, the major PAF-inactivating enzyme. These transfected cells exposed to anti-alpha gal Abs showed reduced cell contraction and motility compared with empty vector-transfected cells. Moreover, in PAEC stimulated with anti-alpha gal Abs, the synthesis of PAF promoted the adhesion of a monocytic cell line as shown by the inhibitory effect of PAF-receptor antagonists and of PAF-AH expression. Finally, studies on cell monolayer demonstrated an enhanced permeability 48 hr after exposure to anti-alpha gal Abs, and this increase was prevented by PAF-inactivation and by PAF-receptor blockade. CONCLUSIONS: These results demonstrate that on stimulation with anti-alpha gal Abs, PAEC synthetize PAF which can contribute to several vascular events involved in xenograft rejection.  相似文献   
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