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1.
The relationship between chronic lymphocytic thyroiditis (CLT) and papillary thyroid carcinoma (PTC) is a subject of controversy. Some investigators suggest a causal relationship, whereas others regard the two as only a coincidental occurrence. An additional complicating factor is the presence of atypical nuclei frequently found within lymphoid infiltrates in CLT, which resemble those in PTC. The finding of the RET-PTC translocations in CLT has been reported by two independent groups of investigators, suggesting that the areas of nuclear atypia in CLT are neoplastic rather than reactive. In the present study, we report additional molecular findings that support the hypothesis that the atypical nuclear changes in CLT may be preneoplastic or neoplastic. We microdissected small areas with atypical nuclei in glands with CLT and observed loss-of-heterozygosity mutations of tumor suppressor genes. These genetic mutations are evidence of clonal preneoplastic or neoplastic changes in the follicular cells of CLT. The clinical malignant potential of these minute foci is likely to be very small but remains to be determined.  相似文献   
2.
Amyloid fat pad aspiration specimens for cases with a clinical suspicion of amyloid typically are stained with Congo red and examined by brightfield microscopy. Congophilia with apple-green birefringence by polarization microscopy (PM) is considered diagnostic for amyloid. Examination of Congo red-stained slides by fluorescent microscopy (FM) is considered by some to be a more sensitive detection method. In this study, we assessed the utility of this technique in cytopathology archival slides from abdominal fat pad aspirations previously stained with Congo red dye. Seventy-eight cases of abdominal fat pad aspirations collected during the last 5 yr and stained with the Congo red procedure were obtained from archival files. Additionally, 20 adipose tissue material slides prepared from the surgical pathology specimens were examined as controls. One representative smear was examined in each case using FM equipped with rhodamine excitation/absorption (540/570 nm) filters. Relevant clinical information was obtained in all cases. Twelve cases (15.4%) of the 78 fat pad aspiration cases were reported originally as positive by Congo red stain using polarization and apple-green birefringence as diagnostic criteria. On review, four cases were deemed unsatisfactory. By FM examination 29 of the 74 (39.2%) cases were reclassified as positive for amyloid. The results were confirmed by immunohistochemical stain for amyloid P protein and electron microscopy. A number of similar distinct fluorescence and immunohistochemical patterns were recognized in the positive cases. Minimally weak fluorescence in the adipose tissue was observed in the control cases. The use of FM in Congo red-stained fat pad smears can improve the detection of amyloid in cytology preparations.  相似文献   
3.
Radical surgery for the solitary bony metastasis from renal-cell carcinoma   总被引:2,自引:0,他引:2  
We carried out excision of a solitary bony metastasis from renal-cell carcinoma in 25 patients in the hope that this would produce a prolonged disease-free interval. Two patients had excisions only, five had amputations and 18 had excision and endoprosthetic replacement. The one-, three- and five-year cumulative survival rates were 88%, 54% and 13%, respectively. There were three complications. One patient developed a local recurrence and three had problems related to the endoprosthesis. We recommend radical excision of a solitary bony metastasis from renal-cell carcinoma to achieve local control of the tumour for the remainder of the patient's life.  相似文献   
4.
5.
Sonographic appearance of focal thyroiditis   总被引:7,自引:0,他引:7  
OBJECTIVE: The purpose of this study is to report the sonographic appearance of focal thyroid nodules that prove to be lymphocytic thyroiditis on fine-needle aspiration. CONCLUSION: In a patient population undergoing sonography for palpable nodular disease without known thyroiditis, focal nodules of thyroiditis had a wide variety of appearances. They most commonly appeared as solid hyperechoic nodules with ill-defined margins. However, the echogenicity was variable, and calcification and cystic-appearing regions were also noted. The vascularity of these nodules as assessed with color Doppler and power Doppler sonography also varied widely. Biopsy of these lesions is still necessary because there are no sonographic features that can reliably diagnose these lesions as thyroiditis and differentiate them from other lesions.  相似文献   
6.
7.
Introduction: Idiopathic systemic capillary leak syndrome (SCLS) is a unique disorder characterized by episodes of massive systemic leak of intravascular fluid leading to volume depletion and shock. A typical attack of SCLS consists of prodromal, leak and post-leak phases. Complications, such as compartment syndrome and pulmonary edema, usually develop during the leak and post-leak phases respectively. Judicious intravenous hydration and early use of vasopressors is the cornerstone of management in such cases.

Areas covered: The purpose of the present review is to provide an up-to-date, evidence-based review of our understanding of SCLS and its management in the light of currently available evidence.

Commentary: Idiopathic SCLS was first described in 1960 and, since then, more than 250 cases have been reported. A large number of cases have been reported over the past one decade, most likely due to improved recognition. In the acute care setting, most patients with SCLS are managed as per the Surviving Sepsis guidelines and receive aggressive volume resuscitation – which is not the optimal management strategy for such patients. There is a need to raise awareness amongst physicians and clinicians in order to improve recognition of this disorder and ensure its appropriate management.  相似文献   

8.
9.

Background

Endoscopic ultrasound guided fine needle aspiration biopsy (EUS‐FNA) has proven to be an effective diagnostic modality for the detection and staging of pancreatic malignancies. In recent years EUS‐FNA has also been used to diagnose lesions of non‐pancreatic sites such as structures in close proximity to the gut wall within the mediastinum, abdomen, pelvis and retro‐peritoneum.

Aims

To evaluate experience with EUS‐FNA of non‐pancreatic sites at a large university medical centre.

Methods

The study cohort included 234 patients who underwent EUS‐FNA of 246 lesions in non‐pancreatic sites (122 peri‐pancreatic and coeliac lymph nodes; 9 peri‐pancreatic masses; other sites: mediastinum 12, gastric 25, liver 27, oesophagus 17, duodenum/colon/rectum 15, retro‐peritoneum 8, lung 7, miscellaneous 4).

Results

The cytology diagnoses were classified as non‐neoplastic/reactive in 82 (33%), atypical/suspicious for malignancy in 25 (10%), malignant in 86 (35%) and non‐diagnostic in 53 (22%) cases. Surgical pathology follow‐up was available in 75 (31%) cases. Excluding the non‐diagnostic cases there were 7 false negative and 3 false positive cases. The sensitivity, specificity and positive predictive value of EUS‐FNA in the diagnosis of lesions of non‐pancreatic sites was 92%, 98% and 97%, respectively.

Conclusions

EUS‐FNA can be effectively used as a diagnostic modality in the diagnosis of lesions from non‐pancreatic sites.  相似文献   
10.

Background

Occupational exposure to hand-transmitted vibration (HTV) is known to cause neurological symptoms such as numbness, reduced manual dexterity, grip strength and sensory perception. The purpose of this longitudinal study was to compare thermotactile perception thresholds for cold (TPTC) and warmth (TPTW) among vibration exposed manual workers and unexposed white collar workers during a follow-up period of 16 years to elucidate if long-term vibration exposure is related to a change in TPT over time.

Methods

The study group consisted of male workers at a production workshop at which some of them were exposed to HTV. They were investigated in 1992 and followed-up in 2008. All participants were physically examined and performed TPT bilaterally at the middle and distal phalanges of the second finger. Two different vibration exposure dosages were calculated for each individual, i.e. the individual cumulative lifetime dose (mh/s2) or a lifetime 8-h equivalent daily exposure (m/s2).

Results

A significant mean threshold difference was found for all subjects of about 4–5 °C and 1–2 °C in TPTW and TPTC, respectively, between follow-up and baseline. No significant mean difference in TPTC between vibration exposed and non-exposed workers at each occasion could be stated to exist. For TPTW a small but significant difference was found for the right index finger only. Age was strongly related to thermotactile perception threshold. The 8-h equivalent exposure level (A (8)) dropped from about 1.3 m/s2 in 1992 to about 0.7 m/s2 in 2008.

Conclusions

A lifetime 8-h equivalent daily exposure to hand-transmitted vibration less than 1.3 m/s2 does not have a significant effect on thermotactile perception. Age, however, has a significant impact on the change of temperature perception thresholds why this covariate has to be considered when using TPT as a tool for health screening.
  相似文献   
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