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91.
92.

Objectives

Structural and functional changes in pulmonary vessels are prevalent at the initial stages of chronic obstructive pulmonary disease (COPD). These vascular alterations can be assessed using cross-sectional area (CSA) of small pulmonary vessels. However, neither in non-COPD smokers nor in COPD patients it has been defined whether the structural changes of pulmonary vessels detected by paired inspiratory and expiratory CT scans are associated with emphysematous changes. We quantified the CSA and low attenuation area (LAA) and evaluated the changes in these parameters in the inspiratory and expiratory phases.

Materials and methods

Fifty consecutive non-COPD smokers and COPD patients were subjected to multi detector-row CT and the percentage of vessels with a CSA less than 5 mm2 as well as the percentage LAA for total lung area (%CSA < 5, %LAA, respectively) were calculated.

Results

The %CSA < 5 correlated negatively with %LAA. The %CSA < 5 was lower in COPD patients with emphysema as compared with non-COPD smokers and COPD patients with or without mild emphysema. In addition, the %CSA < 5 was lower in the no/mild emphysema subgroup as compared with non-COPD smokers. The respiratory phase change of %CSA < 5 in COPD patients was greater than that in non-COPD smokers.

Conclusion

The percentage of small pulmonary vessels decreased as emphysematous changes increase, and this decrease was observed even in patients with no/mild emphysema. Furthermore, respiratory phase changes in CSA were higher in COPD patients than in non-COPD smokers.  相似文献   
93.
OBJECTIVE: We performed a prospective randomized trial in patients with potentially resectable stage IIIA N2 non-small cell lung cancer to confirm the efficacy of induction chemotherapy before surgical resection. METHODS: Patients with stage IIIA N2 non-small cell lung cancer, all with histologically or cytologically confirmed metastases to the ipsilateral mediastinal lymph nodes, were randomly assigned to receive either three cycles of induction chemotherapy (cisplatin at 80 mg/m(2) on 1 day and vindesine at 3 mg/m(2) on 2 days) followed by surgery or surgery alone. RESULTS: This trial was prematurely terminated because the accrual rate was too slow, which lowered the study's statistical power considerably. From June 1993 through April 1998, a total of 62 patients were enrolled, and 31 patients were assigned to each treatment group. The objective clinical response rate of induction chemotherapy was 28%. Complete resection was achieved in 20 patients in the induction chemotherapy group (65%) and 24 in the surgery alone group (77%). Median follow-up was 6.2 years. Median overall survivals were 17 months for the induction group and 16 months for the surgery alone group. The estimated 1-, 3-, and 5-year survivals, respectively, were 68% (95% confidence interval 51%-85%), 23% (95% confidence interval 8%-38%), and 10% (95% confidence interval 0%-20%) for the induction chemotherapy group and 65% (95% confidence interval 48%-82%), 26% (95% confidence interval 11%-41%), and 22% (95% confidence interval 7%-37%) for the surgery alone group. There was no statistically significant difference in survival between the groups (P =.5274). Treatment-related death was not observed in either group. CONCLUSION: This randomized trial to compare induction chemotherapy (cisplatin and vindesine) followed by surgery with surgery alone for patients with stage IIIA N2 non-small cell lung cancer did not demonstrate a survival difference between the groups, although this may have been because the statistical power was limited.  相似文献   
94.
An inducible co-stimulator (ICOS), a recently identified co-stimulatory receptor with a close structural homology of CD28 and CTLA4, is expressed on activated T cells. Anti-ICOS antibody was demonstrated to be effective on prolongation of graft survival after liver transplantation in rats. In this study, we investigated the potency of tolerance induction using the antibody combined with a recombinant adenovirus vector containing CTLA-4Ig cDNA (AdCTLA-4Ig) in rat heart transplantation model. Using a DA-to-Lewis rat heart transplantation model, an anti-rat ICOS antibody and AdCTLA-4Ig were simultaneously administered i.v. into recipients. The tissue specimens from the grafts were removed on various days after transplantation for histological evaluation. Donor-strain skin and heart grafts, and third-party heart allografts were challenged in the recipients with a long-term surviving graft. Splenocytes from the tolerance-induced recipients were used for adoptive transfer study. Anti-ICOS antibody alone did not prolong the survival of heart allograft. AdCTLA-4Ig monotherapy significantly prolonged the survival of heart allograft (Group 4). With a combination of Anti-ICOS antibody and AdCTLA-4Ig, all recipients were resulted in a long-term allograft acceptance for more than 200 days (Group 8). When challenged donor-strain skin grafts in the tolerant rats of Group 4, the skin was rejected, which also lead to a rejection of primary heart allografts. The recipients in Group 8 also rejected donor-strain skin grafts with no rejection of the primary heart grafts. These recipients accepted secondary heart grafts from donor-strain but not third-party. In Group 8 long-term survival recipients showed a high population of CD4+CD25+ regulatory T cell in peripheral blood, and in adoptive transfer study subtraction of these CD4+CD25+ T cells accelerate the rejection of heart graft in secondary irradiated recipients. The present results demonstrated that anti-ICOS antibody combined with AdCTLA-4Ig potently induces a stable immune tolerance after heart allografting in rat, which is mediated by the induction of CD4+CD25+ regulatory T cells. This strategy may be attractive for clinical employment to induce transplantation tolerance.  相似文献   
95.
A 72-year-old man was admitted to another hospital because of general fatigue and dyspnea secondary to renal insufficiency. Abdominal computed tomography (CT) and magnetic resonance imaging showed left atrophic kidney, right hydronephrosis, and an intra-pelvic mass of soft-tissue density located anterior to the sacrum, involving the right ureter at the level between the 5th lumber vertebra and the sacrum. He was referred to our hospital after percutaneous nephrostomy was constructed into right kidney. CT-guided needle biopsy revealed the idiopathic retroperitoneal fibrosis, leading us to give him steroid therapy. Three weeks later, radiographic findings showed a remarkable reduction of the mass and the improvement of the right ureteral stricture.  相似文献   
96.
OBJECTIVE: Short (< or =3 months)- and middle (> or =4 months)-term results of aortic valve replacement (AVR) using 19-mm Carpentier-Edwards Perimount (CEP) bioprosthetic valves and 19-mm Medtronic Mosaic (MM) bioprosthetic valves in patients with small aortic annulus were compared. PATIENTS AND METHODS: At our facility, AVR was performed using bioprostheses in 110 patients from April 1999 to March 2006. Of these patients, 40 were treated using 19-mm CEP (Group C), and 9 using 19-mm MM (Group M). Evaluation by inquiry, physical examination, and echocardiography was performed before, a short term after, and a middle term after surgery, and the effects of AVR were compared. RESULTS: The New York Heart Association (NYHA) functional class grade showed improvements in both groups. The aortic valve peak pressure gradient was 29.8 +/- 10.1 mmHg in Group C and 53.8 +/- 17.3 mmHg in Group M, being higher in Group M, a middle term after surgery. However, the left ventricular mass index (LVMI) showed improvements in both groups compared with the values before surgery, and the left ventricular ejection fraction (LVEF) was maintained. During the middle term after surgery, the frequency of cardiac events showed no significant difference between the two groups. CONCLUSIONS: In the patients treated with 19-mm MM, the aortic valve peak pressure gradient was higher than in those treated with 19-mm CEP, but acceptable improvements in the LVMI, maintenance of the LVEF, and avoidance of cardiac events were observed in both groups.  相似文献   
97.
Seki T  Hida K  Tada M  Koyanagi I  Iwasaki Y 《Neurosurgery》2002,50(5):1075-81; discussion 1081-2
OBJECTIVE: This study examined the effects of varying magnitudes of controlled spinal cord impact to the mouse spinal cord on neurological and histopathological variables to obtain a mouse model of spinal cord injury (SCI). METHODS: A laminectomy of the T10 vertebra was performed on anesthetized C57BL/6 mice. A pneumatic pressure-driven impact was performed on the spinal cord through the dura mater. Experimental groups were subdivided according to the energy of impact (0.25-mm-deep deformations): Group 1 (n = 5), impact velocity at 1 m/s; Group 2 (n = 5), impact velocity at 2 m/s; and Group 3 (n = 5), impact velocity at 3 m/s. Functional deficits over time were evaluated up to 28 days after SCI by testing hindlimb reflex and coordinated motor function. The extent of the lesions was analyzed histopathologically and quantified by a morphometric measurement. RESULTS: Mice of all groups exhibited profound functional deficits immediately after injury and subsequent gradual symptomatic recovery. The degrees of recovery were precisely correlated with the magnitudes of impact. The extent of resultant cord lesions was highly reproducible among animals, with little variance: means +/- standard deviation, 0.86 +/- 0.06/100 mm3 in Group 1; 2.4 +/- 0.28/100 mm3 in Group 2; and 11.0 +/- 1.0/100 mm3 in Group 3. CONCLUSION: Our results indicate that this model provides constant functional and histopathological lesions according to impact energy. This new mouse model of SCI opens a new avenue for studies investigating roles and/or effects of specific genes in the recovery process of SCI.  相似文献   
98.
This is a case report of retroperitoneal leiomyosarcoma in a 61-year-old woman. She presented with a chief complaint of back pain. Computed tomography showed a left huge retroperitoneal tumor. The tumor was removed with left nephrectomy and left hemi-colectomy. Histological examination demonstrated leiomyosarcoma 26 x 20 x 16 cm in diameter and, 3.84 kg in weight. She died of local recurrence causing ileus 2 months after the surgery. Fifty-four cases of retroperitoneal leiomyosarcoma including the present case in the Japanese literature are reviewed.  相似文献   
99.
PURPOSE: We treated three patients who had symptomatic prostatic cysts by transrectal ultrasound-guided puncture, drainage, and sclerotherapy. The procedure and the results are described in this report. MATERIALS AND METHODS: The patients were 60, 73, and 78 years old and complained of difficult voiding. With local anesthesia, transrectal ultrasound-guided puncture and drainage were performed, and then 100 mg of minocycline hydrochloride was infused into the cavity of the cyst. We evaluated the International Prostate Symptom Score (IPSS), urodynamic data, volume of residual urine, complications, and recurrence. RESULTS: There were no complications, and improvements of voiding symptoms were experienced without any recurrences within the 2 years or more of follow-up. CONCLUSION: This minimally invasive treatment by transrectal ultrasound-guided puncture, drainage, and minocycline hydrochloride sclerotherapy is suggested to be promising for the symptomatic prostatic cyst.  相似文献   
100.
Among the bisphosphonates (BPs), nitrogen-containing BPs (N-BPs) have much stronger anti–bone-resorptive actions than non-N–BPs. However, N-BPs have various side effects such as acute influenza-like reactions after their initial administration and osteonecrosis of the jawbones after repeated administration. The mechanisms underlying such effects remain unclear. To overcome these problems, it is important to profile the inflammatory nature of N-BPs. Here, we analyzed the inflammatory reactions induced in mouse ear pinnae by the N-BPs alendronate (Ale) and zoledronate (Zol). We found the following: (i) Ale and Zol each induced two phases of inflammation (early weak and late strong ear swelling); (ii) both phases were augmented by lipopolysaccharides (LPSs; cell-surface constituent of gram-negative bacteria, including oral bacteria), but prevented by inhibitors of the phosphate transporters of solute carrier 20/34 (SLC20/SLC34); (iii) macrophages and neutrophils were involved in both phases of Ale+LPS–induced ear-swelling; (iv) Ale increased or tended to increase various cytokines, and LPS augmented these effects, especially that on interleukin 1β (IL-1β); (v) adenosine triphosphate (ATP) was involved in both phases, and Ale alone or Ale+LPS increased ATP in ear pinnae; (vi) the augmented late-phase swelling induced by Ale+LPS depended on both IL-1 and neutrophil extracellular traps (NETs; neutrophil-derived net-like complexes); (vii) neutrophils, together with macrophages and dendritic cells, also functioned as IL-1β–producing cells, and upon stimulation with IL-1β, neutrophils produced NETs; (viii) stimulation of the purinergic 2X7 (P2X7) receptors by ATP induced IL-1β in ear pinnae; (ix) NET formation by Ale+LPS was confirmed in gingiva, too. These results suggest that (i) N-BPs induce both early-phase and late-phase inflammation via ATP-production and P2X7 receptor stimulation; (ii) N-BPs and LPS induce mutually augmenting responses both early and late phases via ATP-mediated IL-1β production by neutrophils, macrophages, and/or dendritic cells; and (iii) NET production by IL-1β–stimulated neutrophils may mediate the late phase, leading to prolonged inflammation. These results are discussed in relation to the side effects seen in patients treated with N-BPs. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
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