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81.
OBJECTIVE AND STUDY DESIGN: To assess quality of a quick and early diagnosis route (QED) by determining effectiveness and cost-effectiveness of five clinics compared with three conventional outpatient clinics. Prospective economic evaluation. Six-month cohort of all referrals (November 1996-April 1997). SUBJECTS: All referrals for suspected cancers of: upper gastro-intestinal tract; urinary tract, prostate and testis; skin. EFFECTIVENESS: Median days saved between GP referral and date of: diagnostic appointment; consultant decision; intervention. RESULTS: GP referral to diagnostic appointment: QED was effective (median days) for all clinics. Diagnostic appointment to consultant decision: QED was effective for testicular and haematuria clinics. Consultant decision to intervention: QED was effective for haematuria, testicular and melanoma clinics. COST-EFFECTIVENESS: Extra (incremental) NHS cost per patient diagnosed. RESULTS: Less than 5 Pounds per day saved between GP referral and diagnostic appointment for: endoscopy; haematuria; prostate; testicular; melanoma. Less than 3 Pounds per day saved between GP referral and consultant decision for: testicular; haematuria. Less than 3 Pounds per day saved between GP referral and intervention for: endoscopy; haematuria; testicular; melanoma. CONCLUSION: A "quick and early" diagnostic route provides a higher quality service through improved effectiveness and cost-effectiveness compared to conventional outpatients.  相似文献   
82.
A 39-yr-old man with stage IV Hodgkin's disease (HD) involving bone marrow was being evaluated for autologous bone marrow transplantation when he developed diplopia, prompting a lumbar puncture tap for cerebral spinal fluid (CSF) examination. Cytologic examination of the CSF revealed numerous Reed-Sternberg (RS) cells in a polymorphous inflammatory background of small lymphocytes, monocytes, rare plasma cells, and eosinophils. However, magnetic resonance imaging (MRI) studies of the brain and spinal cord failed to reveal evidence of leptomeningeal disease or intracranial masses. Repeat CSF examination again demonstrated cytologic evidence of HD. Immunocytochemical stains established that the RS cells and mononuclear Hodgkin's cells were positive for CD30 and CD20 but negative for CD15; this phenotype was identical to that of RS cells in the initial diagnostic bone marrow biopsy, confirming CSF involvement by HD. The patient was treated with intrathecal methotrexate, 15 mg, 6 days after his bone marrow transplant. After treatment, all subsequent CSF cytology specimens were negative for tumor. In this case of disseminated HD, cytologic examination allowed for early detection of CNS involvement by lymphoma prior to development of radiographically detectable lesions.  相似文献   
83.
An impairment of prefrontal cortical functioning in schizophrenia ('hypofrontality') has been suggested by clinical, neuroimaging, and postmortem brain tissue studies. We used Western immunoblot and Northern hybridization analyses of postmortem brain tissue obtained from 14 schizophrenic patients and 12 control patients of similar ages to measure tissue levels of synaptophysin (a structural synaptic vesicle protein) and of SNAP-25 (a 25-kDa presynaptic protein), and their encoding mRNAs, in Brodmann's area 10 of prefrontal cortex. There were significant decreases in tissue levels of both of these proteins in prefrontal cortex of schizophrenic patients relative to controls. In contrast, tissue levels for the mRNAs encoding these proteins were not decreased in schizophrenic patients. Subsequent labeling of the same Western immunoblots showed no difference in tissue levels of glial fibrillary acidic protein (GFAP) in schizophrenic and control patients. Similarly, subsequent hybridization of the same Northern hybridization membranes showed no difference in tissue levels of GFAP mRNA or of 28S rRNA in schizophrenic and control patients. These alterations in tissue levels of synaptophysin and SNAP-25 are consistent with the idea that the clinically observed 'hypofrontality' of schizophrenia arises from abnormalities of synaptic number or structural integrity in prefrontal cortex.  相似文献   
84.
BACKGROUND: A thoracoabdominal approach has traditionally been described for the resection of tumours of the gastric cardia. The aim of this study was to evaluate a transhiatal approach for resection of cancers of the gastric cardia. METHODS: Twenty consecutive patients undergoing transhiatal gastro-oesophagectomy for cancer of the gastric cardia were studied. Data were collected prospectively with regard to operating time, operative blood loss, intensive care unit (ICU) stay, analgesia use, duration of hospital stay, and pathological details of resection margin clearance and lymph node yield. Results were compared with those of the 20 preceding patients for whom the same prospective information had been recorded following resection via the standard thoracoabdominal approach. RESULTS: The transhiatal approach required a shorter operating time (median 190 (range 105-255) versus 280 (225-330) min; P = 0.004). It resulted in less blood loss (median 405 (180-2000) versus 1000 (420-3200) ml; P = 0.03) and fewer days in the ICU (median 0 (0-31) versus 2 (1-8) days; P = 0.005) despite being performed in an older patient population (median 71 (43-78) versus 63 (59-70) years; P = 0.016). There was no difference in either the lymph node harvest or length or involvement of upper resection margins. CONCLUSION: The transhiatal approach to the resection of tumours at the gastric cardia is a valid and safe alternative to the standard thoracoabdominal technique. This technique avoids thoracotomy and its associated morbidity and is accompanied by reduced blood loss, decreased operating time and a shorter ICU stay.  相似文献   
85.
BACKGROUND: Because adenosine has been alleged to produce both anesthetic and analgesic sparing effects, a randomized, double-blinded study was designed to compare the perioperative effects of adenosine and remifentanil when administered as intravenous adjuvants during general anesthesia for major gynecologic procedures. METHODS: Thirty-two women were assigned randomly to one of two drug treatment groups. After premedication with 0.04 mg/kg intravenous midazolam, anesthesia was induced with 2 micro/kg intravenous fentanyl, 1.5 mg/kg intravenous propofol, and 0.6 mg/kg intravenous rocuronium, and maintained with desflurane, 2%, and nitrous oxide, 65%, in oxygen. Before skin incision, an infusion of either remifentanil (0.02 microg x kg(-1) x min(-1)) or adenosine (25 microg x kg(-1) x min(-1)) was started and subsequently titrated to maintain systolic blood pressure, heart rate, or both within 10-15% of the preincision values. RESULTS: Adenosine and remifentanil infusions were effective anesthetic adjuvants during lower abdominal surgery. Use of adenosine (mean +/- SEM, 166+/-17 microg x kg(-1) x min(-1)) was associated with a significantly greater decrease in systolic blood pressure and higher heart rate values compared with remifentanil (mean +/- SEM, 0.2+/-0.03 microg kg(-1) x min(-1)). Total postoperative opioid analgesic use was 45% and 27% lower in the adenosine group at 0-2 h and 2-24 h after surgery, respectively. CONCLUSIONS: Adjunctive use of a variable-rate infusion of adenosine during desflurane-nitrous oxide anesthesia was associated with acceptable hemodynamic stability during the intraoperative period. Compared with remifentanil, intraoperative use of adenosine was associated with a decreased requirement for opioid analgesics during the first 24 h after operation.  相似文献   
86.
Unfractionated heparin potentiates the anticoagulant action of activated protein C (APC) through several mechanisms, including the recently described enhancement of proteolytic inactivation of factor V. Possible anticoagulant synergism between APC and physiologic glycosaminoglycans, pharmacologic low molecular weight heparins (LMWHs), and other heparin derivatives was studied. Dermatan sulfate showed potent APC-enhancing effect. Commercial LMWHs showed differing abilities to promote APC activity, and the molecular weight of LMWHs correlated with enhancement of APC activity. Degree of sulfation of the glycosaminoglycans influenced APC enhancement. However, because dextran sulfates did not potentiate APC action, the presence of sulfate groups per se on a polysaccharide is not sufficient for APC enhancement. As previously for unfractionated heparin, APC anticoagulant activity was enhanced by glycosaminoglycans when factor V but not factor Va was the substrate. Thus, dermatan sulfate and LMWHs exhibit APC enhancing activity in vitro that could be of physiologic and pharmacologic significance.  相似文献   
87.
BACKGROUND AND PURPOSE: Activation of plasma protein C (PC) zymogen by thrombin-thrombomodulin at the endothelial surface is an important endogenous antithrombotic mechanism. It is unknown whether activated protein C (APC) is generated in vivo in the cerebrovasculature, because there is only limited thrombomodulin expression in human brain vascular endothelium. Therefore, we tested the hypothesis that carotid occlusion produces brain-specific PC activation. METHODS: Blood samples were simultaneously collected from the ipsilateral internal jugular vein and radial artery before and during carotid cross-clamping and on "de-occlusion" in 8 awake patients undergoing routine carotid endarterectomy. Plasma PC zymogen and circulating APC levels were measured using enzyme immunocapture assay and expressed as percent of pooled plasma controls. RESULTS: Internal jugular vein APC levels increased 28% exclusively during carotid occlusion and then decreased 32% with de-occlusion (F=8.1, P<0.005). PC zymogen increased only 5.9% with occlusion (F=6.3, P<0.02), consistent with hemoconcentration. There were no changes in radial artery PC or APC levels. CONCLUSIONS: These findings demonstrate brain-specific protein C activation in humans during carotid occlusion and suggest a protective role for endogenous APC generation during cerebrovascular occlusion.  相似文献   
88.
Three recombinant strains of Mycobacterium bovis Bacille Calmette Guerin (rBCG) were prepared in which the immunogenic B subunit of human Escherichia coli heat labile enterotoxin (LT-Bh) was expressed either as a cytoplasm protein, a cell wall associated lipoprotein or a secreted protein. Intraperitoneal immunisation of mice with these rBCG induced IgG and IgA antibodies to LT-Bh and shifted the serum IgG subclass response to subsequent challenge with purified LT-Bh from IgG1 to an IgG2a. Oral administration of recombinant BCG induced mucosal and serum IgA antibodies to LT-Bh which peaked four months after immunisation. Antibody responses were greater when LT-Bh was expressed as a secreted protein or lipoprotein rather than in the cytoplasm. Oral vaccination with recombinant BCG may be an effective approach, particularly to induce mucosal IgA and prime for a serum TH1 recall response.  相似文献   
89.
90.
Since the inception of the National Health Service in 1948, successive British governments have taken various measures to restrain the growth of the medicines bill. A total of 10 different measures have been introduced with very limited success. The most effective measures have been those directed at increasing the level of generic prescribing; such measures mean that the patient is treated with older, off-patent medicines which, although cheap, are not necessarily cost effective or the most clinically effective. Possible future directions for curtailing expenditure include controlling the price of off-patent branded medicines to the level of generic products, and the initiation of a government policy to actively encourage prescribing of newer medicines where these are shown to be more clinically effective or more cost effective.  相似文献   
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