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101.
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Rhabdomyosarcoma is the most common soft tissue sarcoma in childhood, the majority of which are of the embryonal rhabdomyosarcoma (ER) variety. Present day treatment protocols involve a combination of aggressive surgery, chemotherapy, and radiation therapy. Embryonal rhabdomyosarcoma of the larynx is rare and unlike ER of other regions exhibits excellent response to multimodality treatment without the need for extensive surgery. We report a case of cervical metastases in a 29-year-old man 13 years after treatment of his laryngeal ER. To our knowledge, this is the first reported case of late neck metastases in ER of the larynx and the second reported case of delayed presentation of recurrent disease. A 25-year review of all published reports of ER of the larynx was conducted that highlights the move toward organ preservation with the multimodality treatment protocols. Embryonal rhabdomyosarcoma of the larynx is highly responsive to combination chemoradiotherapy, allowing for excellent cure rates without the need for extensive surgery. Late relapses warrant long-term follow-up.  相似文献   
103.
OBJECTIVE: The optimal surgical procedure for the neck in patients with squamous head and neck cancers is controversial. Selective neck dissections have replaced modified radical neck dissections as the procedure of choice for the clinically negative (N0) neck and are now being considered for patients with early-stage neck disease. We report the long-term local recurrence rates in 100 consecutive patients undergoing a radical or modified radical neck dissection for clinically positive (N+) and N0 neck disease and review comprehensively the literature reporting and comparing regional control rates for both neck dissection types. PATIENTS: The clinical records of 100 consecutive patients who underwent a comprehensive neck dissection (levels I-V) for squamous head and neck cancers with a minimum of a 2-year follow-up were retrospectively reviewed for primary site of disease, clinical and pathologic neck status, histopathologic grade, neck dissection type, and the site and time of recurrence. RESULTS: Complete data were available for 97 patients on whom 99 neck dissections were performed. Three patients died from unknown causes. Seventy-six patients with N+ disease underwent a therapeutic neck dissection, while 24 patients with clinically N0 disease underwent an elective dissection. The overall neck recurrence rate in patients with controlled primary disease was 7%. The neck or regional failure rate for patients completing the recommended adjuvant radiotherapy was 4%. Six (25%) of 24 patients with clinically N0 disease had occult metastases. The recurrence rate for this group was 4%. CONCLUSION: Further study is needed to determine the optimal surgical management of the N0 and limited N+ neck.  相似文献   
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We present a model of the labor market effects of health impairments. In particular, we describe several economic models in which health affects worker productivity and the demand for and supply of market labor services. These models provide a framework for estimating the social cost of prevalent health impairments - a necessary step in conducting cost-benefit analyses and in determining the cost-effectiveness of potential health interventions from a broader social perspective. Our approach suggests that several measures used in the literature provide an incomplete and systematically biased assessment of the economic impact of health impairment or of the treatment of illness and impairment. The problem arises because of the reliance on an approximation at the firm level and from the bias from the neglect of the effect of impairment in shifting the labor market equilibrium. If the illness is prevalent, the effects on labor market equilibrium wage rates could be substantial. In addition, many analyses also ignore the effects of illness on producers' surplus.  相似文献   
106.
Background. Global end diastolic volume (GEDV) has a constantand predictable relationship to intrathoracic blood volume (ITBV).The present study assesses the difference between ITBV derivedfrom GEDV and ITBV measured directly in pigs with acute lunginjury (ALI) and mild haemorrhage. Methods. We caused ALI in 12 anaesthetized pigs by i.v. injectionof oleic acid and removed 10% of estimated blood volume. EVLW,GEDV, ITBV (COLD; Pulsion Medical Systems),  相似文献   
107.
Lower extremity bypass procedures restore function and prevent amputation in many patients with severe peripheral arterial occlusive disease. The regular postoperative use of aspirin offers the dual benefit of extending bypass patency and patient survival. Previous trials of adjunctive oral anticoagulant therapy with warfarin have infrequently combined warfarin with aspirin. We hypothesized that the addition of oral anticoagulant therapy would further enhance the benefits of aspirin but may increase the risk of clinically important bleeding. Eligible patients (N = 831) scheduled for elective lower extremity arterial bypass surgery were randomized to receive either warfarin plus aspirin (WA) (n = 418) or aspirin alone (n = 413). At monthly intervals, the warfarin dose was adjusted to a target international normalized ratio (INR) of 1.4 to 2.8; both groups received aspirin (325 mg/d). The end point of major hemorrhagic events, defined as intracranial hemorrhage or bleeding that required intervention, is reported, and INR values and compliance with warfarin therapy are presented. Major hemorrhagic events occurred more frequently in the WA group (35 in the WA group vs 15 in the aspirin group; p = .02) during a mean follow-up of 38 months. In the WA group, an intracranial hemorrhage occurred in six patients (two had an INR > 3.0), of whom four died; one subdural hemorrhage occurred in the aspirin group. Transfusions and interventions for bleeding were more frequent in the WA group, as were minor bleeding events. Of the 8,946 INR determinations, 58% were in the target range, whereas a higher value occurred in 10% and a lower value in 32%. Compliance with warfarin was maintained in 65% of the patients after the first year of observation. In patients with elective lower extremity bypass procedures, the postoperative adjunctive use of warfarin with aspirin increased the risk of major hemorrhagic events. Most of these events occurred when the INR was in the target range.  相似文献   
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109.
Senescence-associated changes in the prostate are believed to play an important role in the genesis of prostate cancer. In order to provide further information on how aging increases the prostate susceptibility to cancer, we examined the pattern of cyclooxygenase (COX)-2 expression and the concomitant alterations in prostaglandin E(2) (PGE(2)) synthesis in the prostate glands of 4-, 10-, 50- and 100-week-old Fischer 344 rats. This was carried out in the prostatic areas where hormone-induced tumors arise, namely the periurethral ducts of the dorsolateral prostate (DLP). Age-associated changes were also evaluated for pro- and anti-apoptotic factors linked to COX-2 signaling and known to be involved in the normal development of the prostate gland as well as in carcinogenesis. COX-2 expression was increased in the DLP in an age-dependent manner where senescent rats had >3-4-fold higher COX-2 mRNA and protein levels than their juvenile counterparts (P<0.05). The age-related changes in COX-2 were accompanied by a similar up-regulation in the PGE(2) synthesis. Evaluation of mediators of apoptotic signaling showed a significant (P<0.05) decline in the expression levels of the pro-apoptotic BAX (>6-fold) and peroxisome proliferator-activated receptor gamma (>3-fold) and in caspase-3 activity (>2-fold) and an up-regulation of the anti-apoptotic Bcl(2) (>8-fold), PKCalpha (>2-fold) and pAkt (>4-fold) in the 100-week-old rats versus the 4-week-old animals. There was an approximately 15-fold age-dependent decrease in the pro-apoptotic ratio BAX:Bcl(2) and an increase in the anti-apoptotic variable PKCalpha(*)Bcl(2)/BAX in the senescent rats compared with the juvenile ones. These results suggest that increased COX-2 expression can be linked to the decline in the pro-apoptotic signaling in the prostate gland during aging. Subsequently, COX-2 inhibitors can be considered as a promising class of agents to attenuate the increased cell survival and, hence, protect against tumorigenesis in the aging prostate.  相似文献   
110.
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