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81.
PURPOSE OF REVIEW: Traditionally, nephroureterectomy has been the treatment of choice for transitional cell carcinoma of the upper urinary tract. In an effort to preserve renal function, conservative therapy has evolved from complex open surgery to minimally invasive ureteroscopic therapy. Considering the relatively recent emergence of ureteroscopic therapy, a review of technical considerations and treatment outcome is timely. RECENT FINDINGS: There is emerging evidence that ureteroscopic treatment of low grade upper tract lesions provides an acceptable oncologic result while preserving functioning renal parenchyma. In patients with low grade upper tract urothelial lesions, progression is rarely reported. Ureteroscopy has for over a decade been the premier diagnostic tool, with the actively deflectable flexible instrument being employed to map the entire intrarenal collecting system. Improvements in instrumentation and refinement in technique have broadened the application of the ureteroscope in treating upper urinary tract urothelial tumors. SUMMARY: For low grade lesions, which make up more than 50% of all presentations, ureteroscopic management has proven efficacious. As with similar grade lesions in the bladder, these patients require careful, consistent, and often lifelong follow up as many will develop recurrent lesions throughout the urothelium. Here too, ureteroscopy has a central role in surveillance.  相似文献   
82.
Recent experiments in cultured cyst epithelial cells from kidneys of patients with autosomal dominant polycystic kidney disease (ADPKD) have shown that the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) is present in the apical surface of these cells and mediates chloride (Cl-) and fluid secretion in vitro. To determine whether the presence of CF with the expression of mutated CFTR proteins modifies cyst formation in ADPKD, we studied a large family with both inherited diseases. ADPKD in this family is linked to PKD1. The family is composed of 26 members; 11 members with ADPKD, 4 members with CF, and 2 members with both diseases. Renal volumes measured by computerized tomography (CT), calculated creatinine clearances, and other clinical parameters in the family members with ADPKD and CF were compared with those in the family members with ADPKD alone, as well as to a large population of patients with ADPKD. The patients with CF and ADPKD, but not the CF heterozygote carriers with ADPKD, had less severe polycystic kidney and liver disease, as indicated by normal renal function; smaller renal volume, even when corrected for height and body surface area; and the absence of hypertension and liver cysts. These observations suggest that the coexistence of CF may reduce the severity of ADPKD.  相似文献   
83.
Summary  This longitudinal twin study documented that genetic factors explain 44–56% of the between-individual variance in bone loss at femoral neck, lumbar spine, and forearm in postmenopausal Caucasian women, providing a rationale for identifying the specific genes involved. Introduction  Although there is a significant genetic effect on peak BMD, until recently, no substantive studies on heritability of bone loss in human were available. The aim of the study was to estimate the heritability of the bone loss at multiple sites in postmenopausal Caucasian women. Methods  Postmenopausal female monozygotic (MZ) and dizygotic (DZ) twins aged 40 or above at baseline were selected from the TwinsUK registry and followed up for an average of 8 years (range 5–14 years). All twins were noncurrent hormone replacement therapy users and not on any osteoporosis treatment. They had dual-energy X-ray absorptiometry (DXA) scans of their hip, lumbar spine, and forearm several times (range 2–9) during the follow-up period. Individual bone losses at femoral neck, lumbar spine, and forearm were estimated by linear regression modeling. Structural equation modeling was utilized to estimate the heritability of the bone loss. Results  A total of 712 postmenopausal Caucasian female twins (152 MZ and 204 DZ pairs) were included. MZ twins were older and had slightly lower BMD at all sites than DZ twins. DZ twins had slightly higher bone loss at lumbar spine, but similar at femoral neck and forearm compared to MZ twins. Intraclass correlation coefficients (ICC) for the bone loss at all sites were significantly higher in MZ than DZ twin pairs (p = 0.0045, 0.0003, and 0.0007 for femoral neck, lumbar spine, and forearm, respectively), indicating a significant genetic influence on bone loss at these sites. After adjustment for age at baseline and weight change during the follow-up, the heritability estimate was 47% (95% CI 27–63%) for bone loss at femoral neck, 44% (95% CI 27–58%) for lumbar spine, and 56% (95% CI 44–65%) for forearm. Conclusions  Our data suggest that up to 56% of the between-individual variance in bone loss is due to genes, providing a rationale to identify specific genetic factors for bone loss.  相似文献   
84.
In order to solve the partial differential equations that arise in the Hartree-Fock theory for diatomic molecules and in molecular theories that include electron correlation, one needs efficient methods for solving partial differential equations. In this article, we present numerical results for a two-variable model problem of the kind that arises when one solves the Hartree-Fock equations for a diatomic molecule. We compare results obtained using the spline collocation and domain decomposition methods with third-order Hermite splines to results obtained using the more-established finite difference approximation and the successive over-relaxation method. The theory of domain decomposition presented earlier is extended to treat regions that are divided into an arbitrary number of subregions by families of lines parallel to the two coordinate axes. While the domain decomposition method and the finite difference approach both yield results at the micro-Hartree level, the finite difference approach with a 9-point difference formula produces the same level of accuracy with fewer points. The domain decomposition method has the strength that it can be applied to problems with a large number of grid points. The time required to solve a partial differential equation for a fine grid with a large number of points goes down as the number of partitions increases. The reason for this is that the length of time necessary for solving a set of linear equations in each subregion is very much dependent upon the number of equations. Even though a finer partition of the region has more subregions, the time for solving the set of linear equations in each subregion is very much smaller. This feature of the theory may well prove to be a decisive factor for solving the two-electron pair equation, which – for a diatomic molecule – involves solving partial differential equations with five independent variables. The domain decomposition theory also makes it possible to study complex molecules by dividing them into smaller fragments thatare calculated independently. Since the domain decomposition approach makes it possible to decompose the variable space into separate regions in which the equations are solved independently, this approach is well-suited to parallel computing.  相似文献   
85.

OBJECTIVE

To compare the efficacy and tolerability of peripheral androgen blockade using combined low‐dose flutamide plus finasteride vs low‐dose flutamide monotherapy for treating biochemical relapse after the definitive management of prostate adenocarcinoma.

PATIENTS AND METHODS

Fifty‐six men treated for biochemical relapse of prostate cancer were enrolled prospectively in a phase II trial at the Walter Reed Army Medical Center from 1997 to 2001. Thirty‐six men were treated with flutamide (125 mg twice daily) and finasteride (5 mg twice daily), and 20 men received low‐dose flutamide only after biochemical recurrence (prostate‐specific antigen, PSA, level ≥0.4 ng/mL). Cox proportional hazards analyses were used to compare the risk of progression between the groups.

RESULTS

Patients on combined and monotherapy had a median follow‐up of 54 and 43.5 months, respectively. Seven men (19%) in the combined arm remain in the study with no progression, while five (25%) on monotherapy continue and are progression‐free. Men on combined therapy had a greater decrease in their PSA level (P = 0.002). Multivariate analysis showed that men on combined therapy had significantly less risk of progression than men on monotherapy (hazard ratio 0.21, 95% confidence interval 0.07–0.63, P = 0.005). There was no significant difference in the frequency of side‐effects between the groups. Toxicities were reported to be mild.

CONCLUSIONS

Our analysis suggests the therapeutic value of low‐dose flutamide alone or combined with finasteride as first‐line agents in a possible graduated approach for treating PSA‐only recurrent prostate cancer. Due to unwanted metabolic effects associated with traditional hormonal agents, phase III trials comparing both regimens with current therapies are warranted.  相似文献   
86.
87.
Chemical exchange saturation transfer imaging can generate contrast that is sensitive to amide protons associated with proteins and peptides (termed amide proton transfer, APT). In breast cancer, APT contrast may report on underlying changes in microstructural tissue composition. However, to date, there have been no developments or applications of APT chemical exchange saturation transfer to breast cancer. As a result, the aims of this study were to (i) experimentally explore optimal scan parameters for breast chemical exchange saturation transfer near the amide resonance at 3 T, (ii) establish the reliability of APT imaging of healthy fibroglandular tissue, and (iii) demonstrate preliminary results on APT changes in locally advanced breast cancer observed during the course of neoadjuvant chemotherapy. Chemical exchange saturation transfer measurements were experimentally optimized on cross‐linked bovine serum albumin phantoms, and the reliability of APT imaging was assessed in 10 women with no history of breast disease. The mean difference between test–retest APT values was not significantly different from zero, and the individual difference values were not dependent on the average APT value. The 95% confidence interval limits were ±0.70% (α = 0.05), and the repeatability was 1.91. APT measurements were also performed in three women before and after one cycle of chemotherapy. Following therapy, APT increased in the one patient with progressive disease and decreased in the two patients with a partial or complete response. Together, these results suggest that APT imaging may report on treatment response in these patients. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
88.
A retrospective institutional-review-board-approved study was performed evaluating positron emission tomography (PET)–computed tomography (CT) imaging findings of peritoneal and omental involvement of lymphoma. Twelve patients were identified with a wide spectrum of imaging findings on PET–CT including but not limited to peritoneal thickening, ascites, and serosal involvement. Lymphoma is among the rare causes of malignant peritoneal or omental involvement. The most common manifestations of peritoneal lymphomatosis are peritoneal 2-[fluorine 18] fluoro-2-deoxy-d-glucose uptake with corresponding peritoneal thickening and nonobstructive serosal masses on CT.  相似文献   
89.
PURPOSE: Recent advances in laparoscopic surgery as well as increasing experience with these techniques have led to the selection of laparoscopic surgery for many urological procedures. A lesser number of pediatric laparoscopic surgical studies have been reported. Few pediatric comparative laparoscopic versus open surgical procedure studies have been published. We compared 2 groups of similar pediatric patients who underwent partial nephrectomy via the laparoscopic or open technique. MATERIALS AND METHODS: A total of 22 consecutive partial nephrectomies were performed in pediatric patients 3 months to 15 years old. Of these procedures 11 chosen according to surgeon preference were performed laparoscopically and 11 were done by the open technique. Clinical data were obtained by chart review and compared retrospectively in the 2 groups. Demographic data, operative time and blood loss, the perioperative complication rate, hospital stay and costs, postoperative analgesic use and followup findings were compared. RESULTS: Mean operative time in the laparoscopic and open groups was 200.4 and 113.5 minutes, respectively (p <0.0005). Blood loss was less than 50 cc in all patients. In the laparoscopic and open groups mean hospital stay was 25.5 and 32.6 hours (p = 0.068), and mean cost was $6,125 and $4,244 (p = 0.016), respectively. Patients in the laparoscopic group required fewer doses of analgesics than those who underwent open surgery (mean 10.9 versus 21, p = 0.041). CONCLUSIONS: Our findings show that increased operative time and costs are disadvantages of pediatric laparoscopic nephrectomy compared with open techniques. Conversely decreased hospital stay, lower analgesic requirements and cosmesis support the use of laparoscopy for pediatric partial nephrectomy. These differences must be considered when deciding which technique is best for overall patient care.  相似文献   
90.
林云才  笪庆  郑鹏 《武警医学》2008,19(11):972-975
 目的 探讨应用咪达唑仑复合氯胺酮不同给药方法在小儿基础麻醉中的优化方案.方法 200例1~6岁,ASAⅠ~Ⅱ级患儿随机分成以下五组:A组为口服咪达唑仑0.7 mg/kg;B组为口服氯胺酮8 mg/kg;C组为肌注氯胺酮5mg/kg;D组为口服咪达唑仑0.5 mg/kg和氯胺酮4 mg/kg;E组为先口服咪达唑仑0.5 mg/kg,再肌注氯胺酮4 mg/kg.观察各组诱导结果及呼吸循环变化、不良反应.结果 ①A组与B组比较,A组起效更快(P<0.01),合作更好,不良反应较少;②A组、B组均比C组更合作,但不如C组起效更快;③D组和E组相比,患儿更合作,不良反应更少,但起效更慢,两组诱导效果无显著差异(P>0.05).结论 咪达唑仑复合氯胺酮优于单独给药,对循环呼吸影响小;口服给药可行性更佳.  相似文献   
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