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91.
Kowalski LP  Carvalho AL 《Head & neck》2002,24(10):921-924
BACKGROUND: The use of selective neck dissection in a positive neck is still controversial. The object of this study was to ascertain the possibility of doing this procedure in oral cavity carcinoma with a single clinically metastatic lymph node smaller than 6 cm (N1 and N2a). PATIENTS AND METHODS: From 1970 to 1994, we analyzed 164 oral cavity cancer patients with clinically N1 or N2a stage cancer submitted to radical neck dissection. RESULTS: The histologic findings did not confirm a metastatic lymph node in 69 (42.1%) cases (pN0) and showed multiple lymph nodes in 19 (11.6%) cases. Moreover, just one patient (0.6%) had a metastatic lymph node at level IV (one case with multiple lymph nodes) and none at level V. CONCLUSIONS: Because we did not find a single metastatic lymph node at levels IV and V and there was a high incidence of pN0 (57.4%) in patients with clinical N1 stage at level I, these patients could be candidates for a supraomohyoid neck dissection (extended or not to level IV) instead of radical neck dissection.  相似文献   
92.
Firefighters experience a wide range of traumatic events while on duty and are at risk to develop psychopathology and posttraumatic stress disorder (PTSD). According to cognitive models, the person's interpretation of the traumatic event is responsible for the development of PTSD rather than the traumatic event itself. This cross‐sectional study aimed to explore the contribution of perceived threat to explain PTSD symptoms in Portuguese firefighters, after adjusting for potential confounding factors. A sample of 397 firefighters completed self‐report measures of exposure to traumatic events, psychopathology, and PTSD. Perceived threat explained unique variance in PTSD symptoms, R2 = .40, ΔR2 = .02, F(10, 367) = 24.55, p < .001, Cohen's f2 =.03, after adjusting for psychopathology, number, recency, and frequency of the events, and other potential confounding variables. The association between psychopathology and PTSD was also moderated by perceived threat, R2 = .43, ΔR2 = .03, F(11, 366) = 25.33, p < .001, Cohen's f2 =.05. Firefighters may benefit from interventions that focus on perceived threat to prevent PTSD symptoms.  相似文献   
93.
The purpose of this study was to verify the effect of testosterone depletion on healing of surgical skin wounds at different ages and post‐operative periods. Forty‐four Wistar male rats were divided into four groups: Group 1Y (n = 11) – young control, sham‐operated rats (30‐day old); Group 1A (n = 10) – adult control, sham‐operated rats (3 to 4‐month old); Group 2Y (n = 10) – young rats after bilateral orchiectomy; and Group 2A (n = 11) – adult rats after bilateral orchiectomy. After 6 months, a linear incision was performed on the dorsal region of the animals. The resistance of the wound healing was measured in a skin fragment using a tensiometer, on the 7th and 21st post‐operative days. The wound healing resistance was higher in Group 1Y than in Group 2Y after 7 days (P < 0.05). Wound healing resistance at 21 days was higher than at 7 days in all groups (P < 0.05). Late wound healing resistance was not different between young and adult rats. It is concluded that bilateral orchiectomy diminished the wound healing resistance only in young animals at the 7th post‐operative day.  相似文献   
94.
BACKGROUND: This study aims to compare the alterations in the methylation profiles of E-cadherin in oral cancer, especially in tumors with lowest metatastic potential. METHODS: Nine oral verrucous carcinomas (VCs), 20 oral well-differentiated squamous cell carcinomas without lymph node involvement (SCC-pN0), and 17 with lymph node involvement (SCC-pN+) were analyzed using methylation-specific polymerase chain reaction and immunohistochemical expression of E-cadherin gene. RESULTS: The immunohistochemical expression of E-cadherin in VC was significantly higher (p = .016) when compared with SCC-pN0 and SCC-pN+ groups. The E-cadherin gene methylation was not correlated with its abnormal immunohistochemical expression in VC and SCC-pN0. All tumors of the SCC-pN+ group with unmethylated E-cadherin gene showed significant loss of E-cadherin immunoexpression (p = .044). CONCLUSIONS: The E-cadherin gene methylation presence in tumors with lowest invasive and metastatic potential, such as VC, suggests the early involvement of this epigenetic event in the multistep progression of the oral carcinogenesis.  相似文献   
95.
Intracerebral epidermoid tumor: a case report and review of the literature   总被引:9,自引:0,他引:9  
BACKGROUND: Intracerebral epidermoid cysts are rare lesions and may account for only 1.5% of intracranial epidermoid tumors. Cell entrapment from the mesectodermal origin of the neural crest within the primitive cerebral hemisphere may lead to the formation of such rare intracerebral lesions. METHODS: An intracerebral epidermoid cyst located in the right temporal lobe that was surgically treated is presented. The origin, clinical course, radiological features, and surgical treatment of such uncommon lesions are discussed based on a review of the literature.RESULTS: Intraoperative findings revealed an epidermoid tumor. The postoperative course was uneventful and the patient was discharged with no neurological deficits. On long-term follow-up (2 years), there were no signs of recurrence. CONCLUSIONS: Truly intracerebral epidermoid tumors are rarely found. Cells originating from mesectodermal lines may migrate and remain trapped within the primitive cerebral hemisphere while the neural tube is closing, leading to the formation of such intraparenchymal epidermoid tumors. Accurate preoperative diagnosis can be very difficult due to the radiological similarities to other common intracerebral cysts (e.g., astrocytomas or gliomas). Magnetic resonance imaging (MRI) studies, especially with diffusion-weighted images, allow greater accuracy in the preoperative differential diagnosis. Radical surgical removal should be attempted, but a less aggressive surgical strategy should be considered if there is strong adherence between the tumor capsule and the brain tissue, particularly in eloquent areas.  相似文献   
96.
Surgical management of brainstem cavernomas.   总被引:14,自引:0,他引:14  
OBJECT: A careful retrospective analysis of 36 cases was performed to evaluate the pre- and postoperative rates of morbidity that occur in patients with brainstem cavernous angiomas. METHODS: The authors evaluated immediate postoperative and follow-up outcomes with regard to clinical findings, the incidence of preoperative hemorrhage(s), location and size of the lesions, and the timing of the surgical procedure after the last hemorrhagic event. Specifically. the following parameters were analyzed: 1) number of hemorrhages; 2) the precise brainstem location (pontomesencephalic, pons, and medulla oblongata); 3) pre- and postoperative cranial nerve status; 4) pre- and postoperative motor and sensory deficits; 5) size (volume) of the lesions; and 6) pre- and postoperative Karnofsky Performance Scale (KPS) scores. Multiple hemorrhages were observed in 16 patients, particularly in those with pontomesencephalic cavernous angiomas (75%). The mean preoperative KPS score was 70.3 +/- 16.3 (+/- standard deviation). Twenty-six patients (72.2%) presented with cranial nerve impairment, 13 (36.1%) with motor deficits, and 17 (47.2%) with sensory disturbance. Volume of the lesions ranged from 0.18 to 18.18 cm3 (mean 4.75 cm3). Postoperative complications included new cranial nerve deficits in 17 patients, motor deficits in three, and new sensory disturbances in 12 patients. In a mean follow-up period of 21.5 months, KPS scores were 80 to 100 in 22 patients. Timing of surgery (posthemorrhage) and multiple hemorrhages did not influence the long-term results. Higher preoperative KPS scores and smaller-volume lesions, however, were factors associated with a better final outcome (p < 0.05). Major morbidity was related mainly to preoperative status and less to surgical treatment. The incidence of new postoperative cranial nerve deficits was clearly lower than that demonstrated preoperatively because of the brainstem hemorrhages. CONCLUSIONS: Based on these findings, resection of brainstem cavernomas is the treatment of choice in the majority of these cases because of the high incidence of morbidity related to one or often several brainstem hemorrhages.  相似文献   
97.

Introduction

The objective of this study was to show the morphologic characteristics of allograft renal biopsies in renal transplant patients with stable renal function, which can potentially be early markers of allograft dysfunction, after 5 years of follow-up.

Methods

Forty-nine renal transplant patients with stable renal function were submitted to renal biopsies and simultaneous measurement of serum creatinine (Cr). Histology was evaluated using Banff scores, determination of interstitial fibrosis by Sirius red staining and immunohistochemical study of proximal tubule and interstitial compartment (using cytokeratin, vimentin, and myofibroblasts as markers). Biopsies were evaluated according to the presence or absence of the epitheliomesenchymal transition (EMT). The interstitial presence of myofibroblasts and tubular presence of vimentin was also analyzed simultaneously. Renal function was measured over the follow-up period to estimate the reduction of graft function.

Results

Median posttransplant time at enrollment was 105 days. Patients were followed for 64.3 ± 8.5 months. The mean Cr at biopsy time was 1.44 ± 0.33 mg/dL, and after the follow-up it was 1.29 ± 0.27 mg/dL. Nine patients (19%) had a reduction of their graft function. Eleven biopsies (22%) had tubulointerstitial alterations according to Banff score. Seventeen biopsies (34%) presented EMT. Fifteen biopsies (32%) had high interstitial expression of myofibroblasts and tubular vimentin. Using Cox multivariate analysis, HLA and high expression of interstitial myofibroblasts and tubular vimentin were associated with reduction of graft function, yielding a risk of 3.3 (P = .033) and 9.8 (P = .015), respectively.

Conclusion

Fibrogenesis mechanisms occur very early after transplantation and are risk factors for long-term renal function deterioration.  相似文献   
98.
Although the safety of living kidney donation has been well established, prospective studies examining the physical and psychosocial aspects of the donor's quality of life are still scarce. Thus, the purpose of this prospective work was to assess the quality of life of 50 consecutive donors before and after kidney transplantation. All donors were asked to respond to both a donor questionnaire and the short‐form 36‐item health survey (SF‐36). Interviews were individually conducted before, three months after, and over one yr after transplantation. Donation was considered a positive experience by all patients and had no impact on any physical or psychosocial aspect of the donor's life. Improved self‐esteem and better quality of life after donation were reported in 52% of the cases. All donors would donate again and encouraged donation. SF‐36 data indicated improvement in post‐donation mental and physical scores among living donors closely related to recipient. Overall, most donors had a positive experience, felt no changes in quality of life, experienced enhanced self‐esteem, would donate again, and recommended donation.  相似文献   
99.
The lectin Artin M has been shown to accelerate the wound‐healing process. The aims of this study were to evaluate the effects of Artin M on wound healing in the palatal mucosa of rats and to investigate the effects of Artin M on transforming growth factor beta (TGF‐β) and vascular endothelial growth factor (VEGF) secretion by rat gingival fibroblasts. A surgical wound was created on the palatal mucosa of 72 rats divided into three groups according to treatment: C—Control (nontreated), A—Artin M gel, and V—Vehicle. Eight animals per group were sacrificed at 3, 5, and 7 days postsurgery for histology, immunohistochemistry and determination of the levels of cytokines, and growth factors. Gingival fibroblasts were incubated with 2.5 μg/mL of Artin M for 24, 48, and 72 hours. The expression of VEGF and TGF‐β was determined by enzyme‐linked immunosorbent assay. Histologically, at day 7, the Artin M group showed earlier reepithelialization, milder inflammatory infiltration, and increased collagen fiber formation, resulting in faster maturation of granular tissue than in the other groups (p < 0.05). Artin M–induced cell proliferation in vivo and promoted a greater expression of TGF‐β and VEGF in both experiments (p < 0.05). Artin M was effective in healing oral mucosa wounds in rats and was associated with increased TGF‐β and VEGF release, cell proliferation, reepithelialization, and collagen deposition and arrangement of fibers.  相似文献   
100.
Currently, new types of intraocular lenses have been developed aiming to eliminate presbyopia and the use has become more popular. The authors report the case of a patient with bilateral cataract and corneal irregularities and astigmatism higher than 2D in the corneal topography, in which AcrySof ReSTOR intraocular lens was implanted in the left eye associated to relaxing limbal incisions trying to reduce corneal astigmatism. The near and distance postoperative visual acuity were worse than expected, with no improvement with refraction. Apparently, no other reason apart from irregular astigmatism/multifocal lens justified the low vision. After 45 days, with no visual acuity improvement, the intraocular lens was explanted and a monofocal one was implanted. The final corrected visual acuity improved. Thus, the present case emphasizes the need of a correct preoperative selection of patients to implant this type of multifocal lens, with special attention to corneal topography data.  相似文献   
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