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101.
OBJECTIVE: The impact of co-morbid conditions on early and late clinical outcomes after endovascular treatment of abdominal aortic aneurysm (AAA) was assessed in concurrent cohorts of patients stratified with respect to risk for intervention. SUMMARY BACKGROUND DATA: As a minimally invasive strategy for the treatment of AAA, endovascular repair has been embraced with enthusiasm for all prospective patients who are suitable anatomical candidates because of the promise of achieving a durable result with a reduced risk of perioperative morbidity and mortality. METHODS: From April 1994 to March 2001, endovascular AAA repair was performed in 236 patients using commercially available systems. A subset of patients considered at increased risk for intervention (n = 123) were categorized, as such, based on a preexisting history of ischemic coronary artery disease, with documentation of myocardial infarction (60%) or congestive heart failure (35%), or due to the presence of chronic obstructive disease (21%), liver disease, or malignancy. RESULTS: Perioperative mortality (30-day) was 6.5% in the increased-risk patients as compared to 1.8% among those classified as low risk (P = NS). There was no difference between groups in age (74 +/- 9 years vs. 72 +/- 6 years; mean +/- SD), surgical time (235 +/- 95 minutes vs. 219 +/- 84 minutes), blood loss (457 +/- 432 mL vs. 351 +/- 273 mL), postoperative hospital stay (4.8 +/- 3.4 days vs. 4.0 +/- 3.9 days), or days in the ICU (1.3 +/- 1.8 days vs. 0.5 +/- 1.6 days). Patients at increased risk of intervention had larger aneurysms than low-risk patients (59 +/- 13 mm vs. 51 +/- 14 mm; P <.05). Stent grafts were successfully implanted in 116 (95%) increased-risk versus 107 (95%) low-risk patients (P = NS). Conversion rates to open operative repair were similar in increased-risk and low-risk groups at 3% and 5%, respectively. The initial endoleak rate was 22% versus 20%, based on the first CT performed (either at discharge or 1 month; P = NS). To date, increased-risk patients have been followed for 17.4 +/- 15 months and low-risk patients for 16.3 +/- 14 months. Kaplan-Meier analysis for cumulative patient survival demonstrated a reduced probability of survival among those patients initially classified as at increased risk for intervention (P <.05, Mantel-Cox test). Both cohorts had similar two-year primary and secondary clinical success rates of approximately 75% and 80%, respectively. CONCLUSIONS: Early and late clinical outcomes are comparable after endovascular repair of AAA, regardless of risk-stratification. Notably, 2 years after endovascular repair, at least one in five patients was classified as a clinical failure. Given the need for close life-long surveillance and the continued uncertainty associated with clinical outcome, caution is dictated in advocating endovascular treatment for the patient who is otherwise considered an ideal candidate for standard open surgical repair.  相似文献   
102.
103.
Interventional radiologist rather than vascular surgeons have become the predominant clinicians placing inferior vena cava (IVC) filters since the percutaneous device was introduced more than a decade ago. We conducted a retrospective analysis of 592 patients treated at a single institution between 1987 and 2000 to determine the indications, referral pattern, and clinical outcome of IVC filter placement between the radiologist and surgeon groups. Before 1989 all filters were placed by surgeons in the operating room. The adoption of the percutaneous delivery method by radiologists in 1989 led to a dramatic increase in its practice volume accounting for 99 per cent of all filters placed from 1991 to 1993 (P < 0.001). The development of an endovascular program by the vascular surgeons in 1994 led to a steady increase in its IVC filter practice annually (P < 0.05) and accounted for 42 per cent of all filter placements in 2000. A distinct referral pattern also emerged as 74 per cent of all filter placements by surgeons were referred by surgical services. The proportion of filter placement for strict indications remained constant over time between the two groups (P = 0.86). The complications and survival rates were not significantly different between the two groups (P = 0.24). Percutaneous devices have dramatically increased the clinical volume of IVC filter placement by interventional radiologists. Vascular surgeons with endovascular interest are well suited to perform the procedure and can regain referral ground of IVC filter placement.  相似文献   
104.
OBJECTIVE: To investigate opportunities for, and types of decision making in the general practice (primary care) consultation, and examine differences in skills of those doctors who are successful at meeting their patients' preferences and those who are less successful. DESIGN: Observation study of doctor-patient consultations in general practice. PARTICIPANTS: Patients attending for routine appointments in 12 general practice surgeries across Oxfordshire. METHODS: A total of 212 doctor-patient consultations were video-recorded. The patients involved completed a questionnaire to elicit their perceptions of how decisions were made. The video-taped recordings were coded with a new instrument, the Evidence Based Patient Choice Instrument (EBPCI), to classify the number and type of decision-making opportunities arising during each consultation. A total of 149 recordings were coded using the Oxbridge Rating Scale to assess the doctors' consultation styles. RESULTS: There was a range of decision-making opportunities in addition to those involving medical treatment. With the exception of 'fitness for work', decisions were generally 'doctor led'. There was only moderate agreement between patient perceptions of their level of involvement in decision making and the objective ratings using the EBPCI. There was wide variation in the ability of doctors to meet their patients' preferences for involvement. CONCLUSIONS: There are many decisions made in primary care consultations, in addition to those about medical treatments, in which patients could be involved to a greater extent than they currently are. Some doctors are significantly better than others at meeting different patients' preferences for their decision-making role. Patients' perceptions of shared decision making appears to be influenced by the doctors' general consultation skills.  相似文献   
105.
Summary: A case report is described in which abdominal pregnancy was misdiagnosed by ultrasound scanning as a pregnancy within a horn of a bicornuate uterus. Two serum alpha fetoprotein (SAFP) results were greatly elevated and an amniocentesis was performed, the liquor alpha fetoprotein (LAFP) and karyotype were normal. Elective Caesarean section was performed at 38 weeks for a persistent transverse lie and an abdominal pregnancy was found. The outcome was excellent for both the mother and child.
This is the first reported case of amniocentesis and measurement of LAFP in an abdominal pregnancy and confirms abdominal pregnancy as a rare cause of an elevated SAFP.  相似文献   
106.
The objective of this study was to document the experiences in the first Dutch pilot studies of the effect of transplantation of autologous haematopoietic stem cells in patients with therapy-resistant autoimmune disease. The first results in 21 adults and 14 children are promising: remission of the disease was achieved in 13 patients, while in the others a significant reduction of disease activity was seen with a corresponding improvement of the quality of life. Infectious complications were frequently observed. Two children with systemic juvenile idiopathic arthritis developed a fatal infection-associated macrophage activation syndrome. Multicentre randomised studies are necessary to study the effects of autologous stem cell transplantation and modifications such as T-cell depletion.  相似文献   
107.
The main purpose of this study was to compare rectal and axillary temperature measurements in African children. Altogether 573 sick children were seen in an outpatient setting in rural West Africa. Rectal and axillary temperatures were measured and the parent or guardian was asked if they thought that the child had a raised body temperature. Normal ranges were defined from an age matched population of 203 healthy children. A raised axillary temperature predicted a raised rectal temperature with a sensitivity of 98% and a specificity of 88%. The parents' impression that their child had a fever was a less sensitive (89%) and less specific (59%) indicator of raised rectal temperature. A raised axillary temperature is a good screening test for a raised rectal temperature in African children.  相似文献   
108.
RNA splicing is a tightly regulated process. It is essential for gene expression and, therefore, intervenes in every biological phenomenon in mammals. RNA splicing regulation is cell type-specific in such a way that a cellular situation can be characterised by its repertoire of spliced events, the spliceome. Comparison of the splicing repertoire of two situations identifies alternative exons and introns. This regulation involves cis-acting sequences and transacting factors. Mutations, as well as modifications of signalling pathways, can alter the accuracy of splicing. Since deletion of exons or retention of introns within coding sequences modifies the corresponding proteins and functional domains of proteins are encoded by contiguous exons, identifying changes in the spliceome pinpoints functional domains, which are specifically regulated at the level of RNA splicing. We have developed a new method of gene profiling, qualitative gene profiling, that allows the comparative study of the repertoires of spliced events that characterise distinct physiopathological situations. We present in this review the different uses of this new genomic technique that can help each step of the R&D process in the pharmaceutical industry, and that represents a short cut towards functional genomics and pharmacogenomics.  相似文献   
109.
The response of the uteroplacental and fetal circulations and oxygen transfer to injection of E. coli endotoxin into the pregnant sheep was investigated. Endotoxin injection into the mother was comprised of three distinct phases: First came a precipitous fall in arterial pressure and uteroplacental blood flow with an increase in uteroplacental vascular resistance. This phase was followed by a progressive recovery period during which flow, pressure, and resistance returned to control values. A third phase occurred during which arterial pressure and uteroplacental blood flow decreased until death of the animal. Despite the marked changes in uteroplacental hemodynamics and a decrease in uteroplacental oxygen transfer, the fetal circulation did not show any major alteration until the terminal phase of shock, when arterial pressure and umbilical flow decreased. There was a fall in fetal oxygen content difference.  相似文献   
110.
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