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91.
A biologically active human skin allograft, currently distributed under the brand name TheraSkin(?), was examined for safety and efficacy in the treatment of venous leg ulcers (VLUs) and diabetic foot ulcers (DFUs). The objective was to determine if TheraSkin could serve as a safe and effective alternative to bioengineered skin substitutes such as Apligraf(?) and Dermagraft(?). The authors conducted a retrospective study of 214 consecutive patients seen at the Inova Wound Center (Mt Vernon, Virginia), with either a DFU or a VLU. After excluding patients who did not meet the study criteria, the final eligible cohort consisted of 188 subjects, with 134 VLUs and 54 DFUs. Multivariate logistic regression was used to evaluate the relationship between baseline wound size and the proportion of healed wounds after 12 and 20 weeks from initial allograft application. The authors found that by the 12th week, DFUs closed 60.38% of the time and VLUs closed 60.77% of the time. After 20 weeks, the number of closed DFUs increased to 74.1% and the number of VLUs increased to 74.6%. The mean wound size in the DFU group was 6.2 cm(2) (±11.8) and 11.8 cm(2) (±22.5) in the VLU group. The mean number of TheraSkin allografts required ranged from 1 to 8, with an average of 2.03 (±1.47) at the 12-week point and an average of 3.23 (±2.77) at the 20-week point. Multivariate logistic regression was used to calculate the odds of wound healing by week 12 and week 20 in each group. The authors also analyzed adverse events and found TheraSkin to be noncontributory to any adverse events, verifying the safety of TheraSkin in this study population. In this study, TheraSkin has been shown to be highly effective for the treatment of both VLUs and DFUs with an acceptable safety profile.  相似文献   
92.
BACKGROUND CONTEXT: The relationship between disc degeneration and end plate sclerosis is poorly understood. The sand rat is an excellent, economical small-animal model in which disc degeneration is age related, spontaneous, reliable, and well characterized. This model is used here to evaluate disc degeneration, disc cell viability, and vertebral end plate bone mineral density (BMD) in lumbar sites. PURPOSE: To determine the proportion of live and dead cells and end plate bone mineral density in the aging sand rat annulus. STUDY DESIGN: Young and old sand rats were used in work approved by the Institutional Animal Care and Use Committee. Outcome measures were the percentage of live/dead annulus cells in the disc and the BMD of cranial and caudal end plates of lumbar vertebrae. METHODS: Bone densitometry was used to obtain endplate BMD on lumbar spines of 16 young sand rats aged 2 to 6 months and 26 older animals aged 22 to 46 months. X-ray films were analyzed for wedging, end plate calcification, and disc-space narrowing. Additional discs were also harvested and incubated with fluorochromes, and the percentage of live or dead cells were determined for the outer, inner annulus, and entire annulus. RESULTS: Radiographically old animals had significantly greater incidence of lumbar wedging (p<0.004) and a significantly greater incidence of end plate calcification and disc-space narrowing (p<0.01). In the live-dead study, the mean percentage of dead annulus cells for the three age groups were significantly different for the outer annulus (p<0.001), inner annulus (p=0.005), and total annulus (p<0.0001). The percentages of dead cells for the entire annulus were 46.14%+/-7.99% (age 2-6 months), 48.13%+/-17.32% (age, 13-19 months), and 76.80%+/-7.27% (age 26-38 months). The percentage of dead disc cells correlated significantly with age for outer annulus, inner annulus, and total annulus (p<0.006). The percentage of dead cells in the entire annulus and the inner annulus correlated significantly with end plate BMD (p<0.02). CONCLUSIONS: Data are novel and show that in very aged sand rats, end plate BMD is significantly greater than that of young animals. Live/dead cell analyses showed increasing cell death in both outer and inner annulus, which correlated significantly with age and with end plate BMD.  相似文献   
93.
OBJECTIVES: Evaluate current accepted risk factors for well-differentiated thyroid carcinoma, and develop a predictive model to determine one's risk of malignancy given a thyroid nodule. STUDY DESIGN: Retrospective analysis of 600 patients. SUBJECTS AND METHODS: Patients with benign thyroid nodular disease and with well-differentiated thyroid cancer were randomly selected. Patient, clinical, and investigational data were compared by means of univariate and multivariate regression analyses. RESULTS: Age, regional lymphadenopathy, ipsilateral vocal cord palsy, solid and/or calcified nodules, and an aspiration biopsy being malignant or suspicious predicted for cancer (P < 0.05). Regional lymphadenopathy and vocal cord palsy are perfect predictors of malignancy. Multivariate analysis indicated age, solid and/or calcified nodules, and all fine-needle aspiration biopsy results to be significant in assessing risk (P < 0.05). CONCLUSION: Taking individual risk factors in isolation is not always reliable. Using a predictive model, one can anticipate a patient's risk of malignancy when the diagnosis is unclear.  相似文献   
94.
For patients with end-stage kidney failure, kidney transplantation improves both their quality of life and overall life expectancy compared with dialysis, but it is not without adverse effects. Cancer is second to cardiovascular disease as one of the major causes of morbidity and mortality in renal transplant recipients. Prolonged use of modern immunosuppression, which leads to alteration of immune function and immune surveillance, is associated with increased cancer risk. There is now convincing evidence from observational studies and registry data to confirm a 3- to 5-fold increase in overall cancer incidence, with viral-related neoplasia incurring the greatest risk when compare with the general population. Despite the increased risk, little is known about the overall cancer prognosis, screening, treatment strategies, and effectiveness in this population. Cancers can recur, occur de novo, and be transmitted from donor organs posttransplantation. Uncertainties exist as to how modern immunosuppressive agents impact on cancer management and outcomes in these patients, with some agents such as calcineurin inhibitors and azathioprine, being more carcinogenic than others. The newer agents, proliferation signal/mammalian target of rapamycin inhibitors and mycophenolate mofitil, may have some antiproliferative and antitumor activities demonstrated in preclinical and clinical studies, but long-term well-powered trial data are needed to determine whether they are either protective or curative for cancers in renal transplant recipients. In this review, the incidence, etiology, prognosis, and potential approaches to cancer screening and management post–renal transplantation are discussed.  相似文献   
95.
BACKGROUND: Females demonstrate improved cardiac recovery after ischemia/reperfusion injury compared with males. Attenuation of myocardial dysfunction with preischemic estradiol suggests that estrogen may be an important mediator of this cardioprotection. However, it remains unclear whether post-injury estradiol may have clinical potential in the treatment of acute myocardial infarction. We hypothesize that postischemic administration of 17beta-estradiol will decrease myocardial ischemia/reperfusion injury and improve left ventricular cardiac function. MATERIALS AND METHODS: Adult male Sprague Dawley rat hearts (n = 20) (Harlan, Indianapolis, IN) were isolated, perfused with Krebs-Henseleit solution via Langendorff model, and subjected to 15 min of equilibration, 25 min of warm ischemia, and 40 min reperfusion. Experimental hearts received postischemic 17beta-estradiol infusion, 1 nm (n = 4), 10 nm (n = 4), 25 nm (n = 4), or 50 nm (n = 4), throughout reperfusion. Control hearts (n = 4) were infused with perfusate vehicle. RESULTS: Postischemic recovery of left ventricular developed pressure was significantly greater with 1 nm (51.6% +/- 7.4%) and 10 nm estradiol (47.7% +/- 8.6%) than with vehicle (37.8% +/- 9.7%) at end reperfusion. There was also greater recovery of the end diastolic pressure with 1 nm (47.8 +/- 4.0 mmHg) and 10 nm estradiol (54.0 +/- 4.0) compared with vehicle (75.3 +/- 7.5). Further, 1 nm and 10 nm estrogen preserved coronary flow after ischemia and decreased coronary effluent lactated dehydrogenase compared with controls. Estrogen at 25 nm and 50 nm did not provide additional benefit in terms of functional recovery. Estrogen at all concentrations increased extracellular signal-regulated protein kinase phosphorylation. CONCLUSIONS: Postischemic infusion of 17beta-estradiol protects myocardial function and viability. The attractive potential for the clinical application of postischemic estrogen therapy warrants further study to elucidate the mechanistic pathways and differences between males and females.  相似文献   
96.

Background/Purpose

The mission of the combat support hospital (CSH) is to evaluate and treat combatants injured during war operations. The 31st CSH in Balad and Baghdad, Iraq, during Operation Iraqi Freedom 2 also treated many injured civilians, including children. The purpose of this article is to report the experience of the 31st CSH treating pediatric trauma patients.

Methods

A retrospective review of a comprehensive patient database collected in theater was conducted.

Results

From January 1 to December 31, 2004, we treated 99 patients 17 years and younger. The average age of these patients was 10.6 years. Nine died of their wounds. The mean injury severity score was 11.6. Forty-one sustained gunshot wounds, 13 acquired fragment wounds (55% penetrating), and 22 were injured by improvised explosive devices (22%). Seventy-three patients required a total of 191 operations: 18 celiotomies, 8 craniotomies, 23 skeletal fixations, and 75 wound washout/debridements, among others. Predictors of mortality included admission Glasgow Coma Score less than 4 and admission pH less than 7.1.

Conclusions

The primary mission of the CSH in theater remains unchanged, but its role is evolving. With this study, we can begin to understand the needs of wounded children in urban conflict and help guide training and resource allocation in the future.  相似文献   
97.
BACKGROUND AND PURPOSE: We describe a safe and reproducible technique for potassium-titanyl-phosphate (KTP) and lithium triboride (LBO) laser photoselective vaporization prostatectomy (PVP). TECHNIQUE: With the patient under anesthesia in the dorsal lithotomy position, cystoscopy is performed. Using a high-power KTP/LBO laser system, a groove is created along the lateral-median lobe junction from the bladder neck to the verumontanum to delineate the margins of vaporization. The remainder of the ipsilateral lobe is vaporized using a series of overlapping passes along the length of the groove. The contralateral lobe is vaporized in a similar manner. Finally, the median lobe is vaporized from lateral to medial. A 20F urethral catheter is placed at the conclusion of the procedure. RESULTS: This technique has been successful in 240 consecutive patients over an 18-month period. CONCLUSION: This systematic approach has been safe, effective, and reproducible for KTP/LBO laser PVP. It has become our standard technique for this procedure.  相似文献   
98.
99.

Purpose

Citrulline, a nonprotein amino acid synthesized by enterocytes, is a biomarker of bowel length and the capacity to wean from parenteral nutrition. However, the potentially variant effect of jejunal versus ileal excision on plasma citrulline concentration [CIT] has not been studied. This investigation compared serial serum [CIT] and mucosal adaptive potential after proximal versus distal small bowel resection.

Methods

Enterally fed Sprague-Dawley rats underwent sham operation or 50% small bowel resection, either proximal (PR) or distal (DR). [CIT] was measured at operation and weekly for 8 weeks. At necropsy, histologic features reflecting bowel adaptation were evaluated.

Results

By weeks 6–7, [CIT] in both resection groups significantly decreased from baseline (P < 0.05) and was significantly lower than the concentration in sham animals (P < 0.05). There was no difference in [CIT] between PR and DR at any point. Villus height and crypt density were higher in the PR than in the DR group (P ≤ 0.02).

Conclusion

[CIT] effectively differentiates animals undergoing major bowel resection from those with preserved intestinal length. The region of intestinal resection was not a determinant of [CIT]. The remaining bowel in the PR group demonstrated greater adaptive potential histologically. [CIT] is a robust biomarker for intestinal length, irrespective of location of small intestine lost.  相似文献   
100.
Background contextThe role of preoperative (preop) narcotic use and its influence on outcomes after spinal deformity surgery are unknown. It is important to determine which patient factors and comorbidities can affect the success of spinal deformity surgery, a challenging surgery with high rates of complications at baseline.PurposeTo evaluate if preop narcotic use persists after spinal deformity surgery and whether the outcomes are adversely affected by preop narcotic use.Study design/settingRetrospective evaluation of prospectively collected data.Patient sampleTwo hundred fifty-three adult patients (230 females/23 males) undergoing primary spinal deformity surgery were enrolled from 2000 to 2009.Outcome measuresPreoperative and postoperative (postop) narcotic use and changes in Oswestry Disability Index (ODI), Scoliosis Research Society (SRS) pain, and SRS total scores.MethodsPreoperative, 2-year postop, and latest follow-up pain medication use were collected along with ODI, SRS pain, and SRS scores. Preoperative insurance status, surgical and hospitalization demographics, and complications were collected. All patients had a minimum 2-year follow-up (average 47.4 months).ResultsOne hundred sixty-eight nonnarcotic (NoNarc) patients were taking no pain meds or only nonsteroidal anti-inflammatories preoperatively. Eighty-five patients were taking mild/moderate/heavy narcotics before surgery. The average age was 48.2 years for the NoNarc group versus 53.6 years for the Narc group (p<.005). There were significantly more patients with degenerative than adult scoliosis in the Narc group (47 vs. 28, p<.001; mild 19 vs. 24, p<.02; moderate 6 vs. 14, p<.0003; heavy 3 vs. 10, p<.0002). Insurance status (private/Medicare/Medicaid) was similar between the groups (p=.39). At latest follow-up, 137/156 (88%) prior NoNarc patients were still not taking narcotics whereas 48/79 (61%) prior narcotic patients were now off narcotics (p<.001). Significant postop improvements were seen in Narc versus NoNarc groups with regard to ODI (26–15 vs. 44–30.3, p<.001), SRS pain (3.36–3.9 vs. 2.3–3.38, p<.001), and overall SRS outcome (3.36–4 vs. 2.78–3.68, p<.001) scores. A comparison of change in outcome scores between the two groups showed a higher improvement in SRS pain scores for the Narc versus NoNarc group (p<.001).ConclusionsIn adults with degenerative scoliosis taking narcotics a significant decrease in pain medication use was noted after surgery. All outcome scores significantly improved postop in both groups. However, the Narc group had significantly greater improvements in SRS pain scores versus the NoNarc group.  相似文献   
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