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91.
OBJECTIVE: Prosthetic arteriovenous fistulas for hemodialysis vascular access have a high incidence rate of thrombotic occlusions that result in graft failure. This randomized multicenter study was performed to assess the patency rates and the effect of 4-mm to 7-mm grafts on the development of stenoses. METHODS: A total of 109 patients who needed vascular access for hemodialysis were randomized to receive either 6-mm (n = 57) or 4-mm to 7-mm prosthetic brachial-antecubital forearm loop accesses (polytetrafluoroethylene). Duplex scanning, with measurement of blood flow and peak systolic velocity and detection of stenoses (>50%), was performed at 1, 6, and 12 months after surgery. Clinical data were obtained in a prospective manner and primary, assisted primary, and secondary patency rates were calculated with the Kaplan-Meier life-table analysis. Statistical analysis was performed with the independent samples t test and chi(2) test. RESULTS: At 1 year, patency rates were similar for both 4-mm to 7-mm and 6-mm prostheses (primary, 46% versus 43%; assisted primary, 62% versus 58%; secondary, 87% versus 91%). The incidence rate of thrombotic occlusion was comparable for both groups (0.74/patient-year versus 0.88/patient-year; P >.05). Mean graft flow at 1, 6, and 12 months was 1416 versus 1415 mL/min, 1345 versus 1319 mL/min, and 1595 versus 1265 mL/min (P >.05) for 4-mm to 7-mm and 6-mm grafts, respectively. Also, no differences in peak systolic velocities in any part of the grafts were observed. The percentage of stenoses detected was equal in both groups at 1 year after surgery (27% versus 20%; P >.05). CONCLUSION: A 4-mm to 7-mm tapered prosthetic brachial-antecubital forearm loop access did not reduce the incidence rates of stenoses and thrombotic occlusions compared with a 6-mm prosthetic conduit. Moreover, no differences in patency rates were observed. Therefore, we believe that the 4-mm to 7-mm graft should not be used routinely for hemodialysis vascular access.  相似文献   
92.
A multicenter, open-label, randomized efficacy and safety study was performed with combined human chorionic gonadotropin (hCG) and recombinant follicle-stimulating hormone (recFSH) (Puregon(R)) treatment to induce spermatogenesis in hypogonadotropic hypogonadal male patients. Patients were pretreated for 16 weeks with hCG to normalize testosterone levels. A total of 30 of 49 (61%) subjects had normalized testosterone levels but were still azoospermic after the hCG-alone phase. These patients were randomized into 2 treatment schemes with recFSH (2 x 225 IU recFSH per week [group A] or 3 x 150 IU recFSH per week [group B]), in combination with hCG for a period of 48 weeks. Total testosterone increased during the hCG-alone period from 1.08 and 1.22 ng/mL to 6.26 and 4.52 ng/mL for groups A and B, respectively. Combined gonadotropin treatment was effective in inducing spermatogenesis (sperm count >/=1 x 10(6)/mL) in 14 of 30 subjects (47%) and this was achieved after a median duration of treatment of approximately 5.5 months. Treatment time necessary for first sperm cells to appear in the ejaculate was related to the initial testicular volume. Subjects with a history of maldescended testes (11 of 30 subjects, 37%) showed a lower mean response to treatment as indicated by the relatively lower number of subjects reaching levels of at least 1 x 10(6) sperm cells per milliliter. Combined testicular volume increased during combined gonadotropin treatment from 11.4 to 24.0 mL. Although subjects with a history of maldescended testes had a lower starting testicular volume, subjects with and without a history of maldescended testes showed approximately the same relative increase in testicular volume. Total testosterone levels showed only a minor further increase during the combined gonadotropin treatment period. In conclusion, a weekly dose of 450 IU (3 x 150 IU or 2 x 225 IU) recFSH, in addition to hCG, was able to induce spermatogenesis in many hypogonadotropic azoospermic men who failed to respond to treatment with hCG alone.  相似文献   
93.

OBJECTIVE

To evaluate, in a long‐term follow‐up of T1 high‐grade bladder cancer treated in a prospective, randomized trial, whether fluorescence diagnosis (FD) increases recurrence‐free survival (RFS) or reduces progression to muscle‐invasive stages.

PATIENTS AND METHODS

In all, 191 patients with suspected superficial bladder cancer were treated with transurethral resection under white light (WL) or with FD; 46 presented with initial T1 high‐grade BC (WL, 25; FD, 21). There were no differences in multifocality of tumours, concomitant carcinoma in situ or tumour size in either group.

RESULTS

Patients were followed for a median of 7.3 (WL) and 7.5 (FD) years to evaluate RFS. In the WL group there were 11, and in the FD group three, recurrent tumours of the same stage and grade. The RFS at 4 and 8 years was 69% and 52% in the WL, and 91% and 80% in FD group, respectively. With FD, the RFS was significantly longer according to Kaplan‐Meier analysis (P = 0.025). In the WL group, three (12%), and in the FD group four (19%) patients progressed to muscle‐invasive stages (≥ T2).

CONCLUSION

In initial T1 high‐grade bladder cancer, FD is significantly better than conventional WL transurethral resection for RFS. However, the progression rate to muscle‐invasive disease was not reduced by FD. Thus the clinical course (progression) of T1 high‐grade bladder cancer remains unaffected by FD.  相似文献   
94.
Adolescent idiopathic scoliosis (AIS) represents a rare condition with a potentially detrimental impact on young patients. Despite vast clinical research and published treatment guidelines and algorithms, the optimal therapeutic choice for these patients remains highly controversial. While advocates of early surgery emphasize the benefits of surgical deformity correction with regard to physical and psychological outcome, the opponents base their arguments on the high risk of complications and a lack of documented subjective long-term outcome. In the present paper, the authors were invited to debate the opposite positions of "pro" versus "contra" surgical treatment of AIS, based on the currently available evidence and published guidelines.  相似文献   
95.
96.
Background Osteosynthesis of clavicular fractures is sometimes indicated. Since plate fixation may lead to complications, we have used elastic stable intramedullary nailing and report our experience of midclavicular fractures in 32 adults.

Patients and methods From 2000 to 2005, we treated 32 adults (26 men), median age 40 (19-66) years, by intramedullary nailing with a titanium elastic nail (TEN). All patients were re-examined after median 27 (12-59) months.

Results Nonunion was not observed. 20 clavicles healed without shortening. 12 clavicles healed with shortening of more than 5 mm. Migration of the TEN in 8 patients required secondary shortening of the nail in 5 of them. Nail breakage after fracture healing was observed twice. The nails were removed in 29 patients after a median of 6 (1.3-15) months postoperatively. No patient sustained a re-fracture after TEN removal. The mean Constant score was 95 (SD 1.9) points and the mean DASH score was 5 (SD 2.3) points.

Interpretation Intramedullary stabilization of midclavicular fractures with a titanium elastic nail is a minimally invasive technique with good cosmetic and functional results. Intramedullary fixation can be seen as an alternative to plate fixation and nonoperative treatment.  相似文献   
97.
A prospective, randomized study was performed in an ovine model to compare the efficacy of an anorganic bovine-derived hydroxyapatite matrix combined with a synthetic 15 amino acid residue (ABM/P-15) in facilitating lumbar interbody fusion when compared with autogenous bone harvested from the iliac crest. P-15 is a biomimetic to the cell-binding site of Type-I collagen for bone-forming cells. When combined with ABM, it creates the necessary scaffold to initiate cell invasion, binding, and subsequent osteogenesis. In this study, six adult ewes underwent anterior-lateral interbody fusion at L3/L4 and L4/L5 using PEEK interbody rings filled with autogenous bone at one level and ABM/P-15 at the other level and no additional instrumentation. Clinical CT scans were obtained at 3 and 6 months; micro-CT scans and histomorphometry analyses were performed after euthanization at 6 months. Clinical CT scan analysis showed that all autograft and ABM/P-15 treated levels had radiographically fused outside of the rings at the 3-month study time point. Although the clinical CT scans of the autograft treatment group showed significantly better fusion within the PEEK rings than ABM/P-15 at 3 months, micro-CT scans, clinical CT scans, and histomorphometric analyses showed there were no statistical differences between the two treatment groups at 6 months. Thus, ABM/P-15 was as successful as autogenous bone graft in producing lumbar spinal fusion in an ovine model, and it should be further evaluated in clinical studies.  相似文献   
98.
Mycotic aneurysms leading to aortoduodenal fistula (ADF) are associated with high morbidity and mortality. We report a patient with a mycotic aneurysm and ADF who required emergency laparotomy. After excision of the aneurysm, vascular reconstruction was performed using an autologous graft. The left long saphenous vein was harvested and constructed into a spiral graft. The graft was inserted using a standard inlay technique. After 12 months the patient is in good health. No inflammation or dilation of the saphenous vein spiral graft has been noted. We suggest that in the emergency treatment of mycotic abdominal aneurysm, aortic reconstruction with saphenous vein spiral graft is a valuable option.  相似文献   
99.
Evaluation of new prosthetic meshes for ventral hernia repair   总被引:5,自引:0,他引:5  
Background In hernia repair, particularly laparoscopic hernia repair, direct contact between mesh and abdominal organs cannot always be avoided. Several mesh materials and composite meshes have been developed to decrease subsequent adhesion formation. Recently, new meshes have been introduced. In an experimental rat study, their value was established and compared with that of meshes already available on the market. Methods In 200 rats, eight different meshes were placed intraperitoneally and in direct contact with abdominal viscera. The following meshes were tested: polypropylene (Prolene), e-PTFE (Dualmesh), polypropylene– polyglecaprone composite (Ultrapro), titanium–polypropylene composite (Timesh), polypropylene with carboxymethylcellulose–sodium hyaluronate coating (Sepramesh), polyester with collagen-polyethylene glycol–glycerol coating (Parietex Composite), polypropylene–polydioxanone composite with oxidized cellulose coating (Proceed), and bovine pericardium (Tutomesh). At 7 and then at 30 days postoperatively, adhesion formation, mesh incorporation, tensile strength, shrinkage, and infection were scored by two independent observers. Results Parietex Composite, Sepramesh, and Tutomesh resulted in decreased surface coverage with adhesions, whereas Prolene, Dualmesh, Ultrapro, Timesh, and Proceed resulted in increased adhesion coverage. Parietex Composite, Prolene, Ultrapro, and Sepramesh resulted in the most mesh incorporation. Dualmesh and Tutomesh resulted in significantly increased shrinkage. There were no differences in mesh infection. Parietex Composite and Dualmesh resulted in a moderate inflammatory reaction, as compared with the mild reaction the other meshes exhibited. Conclusion Parietex Composite and Sepramesh combine minimal adhesion formation with maximum mesh incorporation and tensile strength. The authors recommend the use of these meshes for hernia repair in which direct contact with the abdominal viscera cannot be avoided.  相似文献   
100.
AIM OF THE STUDY: To study the survival of patients with thyroid cancer operated in the same centre from 1978 to 1999. PATIENTS AND METHOD: This retrospective study included 218 patients operated on for thyroid carcinoma from january 1978 to december 1999. Modified neck dissection was performed only in the presence of one or more suspected lymph nodes. The stage of the cancer was defined according to the last TNM classification (1997). Survival data were taken from the Geneva Tumour Registry (168 patients = 77% of the series, 109 papillary carcinomas, 37 follicular, 14 undifferentiated and 8 medullary carcinomas). RESULTS: The overall 5, 10 and 15-year survival rates were respectively 88%, 84% and 80%. Papillary carcinoma was associated with the best survival at 5, 10 and 15 years (99%, 97% and 93%), despite a recurrence rate of 20% treated mainly by surgery often associated with radioiodine therapy. Follicular carcinoma had a survival rate of 83% at 5 years and 75% at 10 years. Undifferentiated carcinoma had a median survival rate of 56 days. None of the 8 patients with medullary carcinoma had died from that cancer in this series. CONCLUSION: Thyroid carcinoma carries such a good prognosis (except for undifferentiated carcinoma) that invasive surgery at first operation, like radical neck dissection, is not justified, despite a high rate of recurrence.  相似文献   
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