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31.
Basic determinants for FM responses in the inferior colliculus of rats   总被引:2,自引:0,他引:2  
Summary The response of 835 click-sensitive neurons in the inferior colliculus (IC) to ramp frequency modulated (FM) tones was studied in the anaesthetized rat. More than 70% of the cells were sensitive to the FM sound, and over 25% were FM specialized. Systematic variations of the stimulus parameters showed that sweep velocity, sweep range, and intensity of the FM signal were the 3 basic determinants for the unit response. For anFM specialized cell, the response pattern to each of the parameters was either monotonic or bell-shaped. The population statistics of response patterns to the FM parameters, including the tuning factors, were generated. A stimulus domain was proposed to represent thereceptive space of the FM cells.  相似文献   
32.
Epstein-Barr virus (EBV)-associated smooth muscle tumor (SMT) is a recognized but uncommon disease that is found to occur in patients with immunocompromised conditions such as acquired immunodeficiency syndrome (AIDS). These tumors may be multifocal and located at unusual sites, such as the brain and liver. This report describes the case of 2 AIDS patients with EBV-associated SMT and highlights the features and outcome of this rare but potentially important tumor in human immunodeficiency virus management.  相似文献   
33.
A pineal mass in a patient with acquired immunodeficiency syndrome (AIDS) is reported. Computed tomography (CT) scan revealed a nodular mass in the pineal region with foci of calcification and obstruction of the aqueduct mimicking a pineal tumor. At autopsy, the brain revealed a well-circumscribed lesion with central necrosis in the pineal region suggestive of toxoplasma and involving the periaqueductal area. Susceptibility of a patient with AIDS to opportunistic infections should be considered.  相似文献   
34.
Background: Few data are available on the cost, safety, and long-termefficacy of single agent high-dose melphalan (HDM) followed by autologousbone marrow (ABMT) or blood stem cell (ABSCT) transplantation in the salvagetherapy of Hodgkins disease (HD).Patients and methods: From February 1981 to September 1996, 23 patientswith relapsed (n = 15) or refractory (n = 8) HD received salvage therapywith HDM 140–200 mg/m2 followed by non-cryopreservedABMT (n = 18) or cryopreserved ABSCT (n = 5). The cost of HDM/ABSCT in 1996,from initial consultation until transfer back to referring physician, wasdetermined and compared to the estimated costs of two multi-agent regimenscommonly used for HD.Results: HDM was well tolerated with no early transplant-relatedmortality. The five-year overall and progression-free survival rates were52% and 50%, respectively. The average total cost in Canadianfunds of HDM/ABSCT in 1996 was $34,400/patient. This cost wasestimated to be $4,700–6,800 cheaper per patient than themulti-agent high-dose regimens.Conclusion: These data suggest that HDM is safe, feasible, active, andreasonably inexpensive salvage therapy for patients with relapsed/refractoryHD.  相似文献   
35.
Parasitic nematode worms which produce filariasis in humans place approximately one billion people at risk in more than 75 countries. More than 100 million people are infected with these diseases and are recognized as being of significant military importance. During World War II, filariasis was among the leading causes of medical evacuation from the entire South Pacific area. Agents available to treat the diseases exhibit significant toxicity. Better drugs are urgently needed. Data are reported from work using a Mongolian jird animal model on a new class of potential drugs, thiosemicarbazones. These compounds exhibit activity against the parasites which cause both lymphatic filariasis and the "onchocerciasis type" of the disease.  相似文献   
36.
37.
BACKGROUND: A study was performed to determine the type and frequency of ocular injuries in patients with major trauma. METHODS: All patients with ocular and adnexal injuries (n = 178) among 1,119 patients admitted with major trauma (Injury Severity Score >15) to the Royal Prince Alfred Hospital from July 1990 to December 1997 were analyzed. RESULTS: Sixteen percent of the major trauma cohort had ocular or orbital trauma. Fifty-five percent of patients with injuries involving the face had ocular or orbital injuries. A range of ocular injuries was seen. Analysis of the major trauma cohort showed that motor vehicle drivers, orbital and base of skull fractures, eyelid lacerations, and superficial eye injuries were strongly associated with vision-threatening injury. CONCLUSION: Patients with major trauma and facial injuries have a high risk of vision-threatening injury. Patients with orbital fractures, base of skull fracture, eyelid lacerations, and superficial eye injuries should be assessed by an ophthalmologist as part of the early management of their trauma to determine whether an ocular injury is present.  相似文献   
38.

Introduction  

This report describes the isolation and characterization of three new murine mammary epithelial cell lines derived from mammary tumors from MMTV (mouse mammary tumor virus)/activated Neu + TβRII-AS (transforming growth factor [TGF]-β type II receptor antisense RNA) bigenic mice (BRI-JM01 and BRI-JM05 cell lines) and MMTV/activated Neu transgenic mice (BRI-JM04 cell line).  相似文献   
39.
PURPOSE: Recent studies have shown that tissue factor (TF) may be involved in tumor angiogenesis and metastasis. The role of TF in hepatocellular carcinoma (HCC) was unknown. This study evaluated whether TF expression correlates with microvessel density (MVD), vascular endothelial growth factor (VEGF) expression, tumor invasiveness, and prognosis in human HCC. EXPERIMENTAL DESIGN: Tissue samples were obtained from 58 specimens of resected HCC. Immunohistochemical expression of TF was examined, and tumor MVD was evaluated using CD34 as the endothelial marker. TF and VEGF protein levels in the tumor cytosol were quantified by ELISA. Clinicopathologic and follow-up data of patients were prospectively collected. RESULTS: The immunohistochemical expression of TF in the tumors correlated significantly with tumor MVD (P = 0.002). The median cytosolic TF protein level in the tumors was 720 pg/mg total protein (range, 67-2406 pg/mg total protein). A significant positive correlation was found between TF and VEGF levels in the tumor cytosol (r = 0.475, P < 0.001). High tumor cytosolic TF level was associated with venous invasion (P = 0.004), microsatellite nodules (P = 0.024), unencapsulated tumor (P = 0.007), and advanced tumor stage (P = 0.010). A higher than median tumor cytosolic TF level was an independent predictor of poor survival (risk ratio, 1.836; 95% confidence interval 1.130-5.312, P = 0.023). CONCLUSIONS: This study shows that TF is related to tumor angiogenesis and invasiveness in HCC. Evaluation of tumor TF expression may be useful as a prognostic indicator in patients with HCC.  相似文献   
40.
OBJECTIVE: To assess the antibody response to influenza vaccine of children vertically infected with HIV. DESIGN: Prospective study in HIV infected children vaccinated during the winter of 1994-5. SETTING: Family HIV clinic at St Mary's Hospital, Paddington. SUBJECTS: 25 children, aged 1-11 years, vertically infected with HIV. MAIN OUTCOME MEASURES: Responses to influenza antigens (H1N1-A/Taiwan/1/86, H3N2-A/Shandong/9/93, B/Panama/45/ 90) were tested by haemagglutination inhibition. Antibody responses were assessed according to clinical symptoms and immune function, stratified according to the 1994 revised classification for HIV infection in children. RESULTS: 23 children (92%) had either very low or no detectable antibody before vaccination. New protective antibody responses were made by 10 children (40%): in seven to a single antigen, in two to two antigens, and in one to all three antigens. For each antigen there was an overall small increase in the mean geometric titre of antibody produced, but this only reached a protective level for antigen H1N1 and for children with minimal symptoms. Less symptomatic children were significantly more likely to produce a protective antibody response to influenza vaccination. No association was found between immune function, as measured by CD4 count, and vaccine response. CONCLUSIONS: Only vaccination of the least symptomatic HIV infected children against influenza is likely to be effective. This will not only protect them against influenza, but will also protect other more immunosuppressed and vulnerable members of their families.  相似文献   
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