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51.
Herein, a novel magnetic metal–organic framework functionalized (MMOF) with 2-aminothiophenol (2-ATP) was fabricated and employed for separation/preconcentration of trace silver amounts. At first magnetite nanoparticles (Fe3O4 NPs) were synthesized and then coated with SiO2. Thereafter, the Fe3O4@SiO2 nanoparticles were modified with 2-ATP. Finally, the functionalized MMOF was prepared by the fabrication of MIL-101(Cr) in the presence of Fe3O4@SiO2@2-ATP NPs. MIL-101(Cr)/Fe3O4@SiO2@2-ATP nanocomposite was characterized with FT-IR, SEM, elemental analysis, XRD and VSM and then utilized in the separation/determination of silver ions in various real samples. The effects of diverse experimental variables such as pH, uptake time, adsorbent amount, desorption time, eluent concentration and volume were studied comprehensively employing experimental design methodology. After optimization, LOD and linearity were 0.05 ng mL−1 and 0.2–200 ng mL−1, respectively. Repeatability of the new method was determined based on RSD value for 5, 50, 150 ng mL−1 (n = 5) concentrations which was 9.3%, 6.8% and 4.5%, respectively. Ultimately, the outlined method was utilized in the separation/determination of silver ions in various water and wastewater samples satisfactorily.

A scheme for the synthesis of MIL-101/Fe3O4@SiO2@2-ATP nanocomposite.  相似文献   
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Background:

Cathepsin L is a member of papain superfamily. It seems to promote T-cell survival, selection maturation in the thymus and enhance the antigen presentation. Cathepsin L plays an important role in tumor necrosis factors (TNF-α) induced cell death. Also it degrades the tight junction between cornedesomses in the epidermis. Elevated expression of cathepsin L has been found in many inflammatory and neoplastic diseases.

Objective:

The aim of this study was to determine immunohistochemical expression of cathepsin L in atopic dermatitis (AD) and lichen planus (LP) patients in order to evaluate its role in the pathogenesis of both diseases.

Materials and Methods:

This study included 15 patients with AD (Group I), 15 patients with LP (Group II), in addition to 10 healthy skin specimens served as controls (Group III). Punch biopsies were taken from lesional skin of the patients and controls for immunohistochemical detection of cathepsin L expression.

Results:

Highly significant increase was found in cathepsin L expression in AD and LP patients compared to controls [P = 0.001].

Conclusion:

Cathepsin L could be implicated as an important protease in the pathogenesis of AD and LP. It could be a useful marker for assessing AD severity.  相似文献   
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Background/Aim:

Thrombocytosis is found to be associated with unfavorable prognosis in esophageal carcinoma. Platelets produce thymidine phosphorylase which is a platelet-derived endothelial cell growth factor with angiogenic activity. Increased platelet count may be translated into enhanced tumor growth. We examined the relation between platelet count and several prognostic variables in patients with esophageal cancer.

Patients and Methods:

Three hundred and eighty-one cases with esophageal cancer that underwent esophagectomy in a referral cancer institute during a 5-year period were studied retrospectively. The relation between preoperative platelet count and patient age, gender, site of tumor, presence of multiple cancers and clinicopathological characteristics including histological type, tumor size, depth of penetration (T), lymph node involvement (N), distant metastasis (M), degree of differentiation, presence of vascular, lymphatic and perineural invasion was examined.

Results:

Squamous cell carcinoma (SCC) constituted 93% and adenocarcinoma 7% of cases. Most of patients were in stage III, followed by stage II. The mean platelet count was 245±76 (× 109 /L). There was no statistically significant correlation between platelet counts with prognostic factors except a weak linear correlation between platelet count and and tumor size (P= 0.03, Pearson correlation coefficient: 0.16). Patients with adenocarcinoma had a higher platelet count than those with SCC (P= 0.003).

Conclusion:

Platelet count does not correlate with prognostic factors in esophageal cancer. However, it is significantly different between SCC and adenocarcinoma of esophagus.  相似文献   
57.
Carcinoma originating in bone is uncommon; most of them apparently arise in odontogenic cysts. In this paper, we report an extremely rare case in which, verrucous carcinoma originated from an odontogenic cyst. This lesion was firm and non-tender on palpation and had a white-pink appearance. It was encased in the anterior aspect of the maxilla and exhibited microscopic features of verrucous carcinoma of the oral mucosa. After surgical enucleation, no recurrence or metastasis has been observed up to now. It is mandatory to correlate the clinical and histopathologic findings to establish a true diagnosis.  相似文献   
58.
Although the incidence of ocular trauma has been clearly described in developed countries, few published data are available on the epidemiology and the effects of parameters that can influence the incidence and severity of ocular injuries in Iran. The present study tried to determine epidemiological aspects of ocular traumatic injuries and evaluate their effects on different types of ocular injury. The case series included 1950 consecutive patients with acute ophthalmic trauma presented to the emergency ward of Farabi Hospital in Tehran. Information was collected by interviewing patients and having them fill in a questionnaire. The final diagnosis was made by a medical resident. If there was a difficulty or doubt in diagnosis or classification, confirmation of diagnosis was made by senior faculty. Ocular injuries were classified into globe and non-globe injuries according to the site of injury. Mechanical globe injuries were classified according to Birmingham Eye Trauma Terminology (BETT) into closed and open injuries. The mean age of patients was 28.8 ± 12.8 years; 87.6% were male. The most common causes of injury were work-related (49.0%) and chance events (42.0%). The most frequent ocular injury was globe injury (95.6%), including mechanical (77.6% closed and 5.9% open), chemical (7.6%), photic (2.3%) and thermal (2.2%) injuries. Non-globe injury also occurred in 10.8% of patients; both globe and non-globe injuries occurred in 6.5% of patients. The hospitalization rate in all patients was 8.8%. Previous history of eye trauma was significantly more common in the group with isolated globe injuries (P < 0.001). History of eye trauma is a risk factor for globe injuries and female gender is a risk factor only for non-globe injuries. These two factors may predict future eye injury and increase its risk by 5.2 and 1.6 times, respectively.  相似文献   
59.
BackgroundCurrently, evidence supports the use of adjuvant endocrine therapy with aromatase inhibitors in post-menopausal patients with hormone receptor (HR)—positive breast cancer. The goal of the current study is to understand the effect of patient age and health status on oncologists' decision to recommend adjuvant treatment (endocrine therapy and chemotherapy) in older women with HR-positive breast cancer.Patients and MethodsAn online survey was conducted, with questions related to a hypothetical patient of varying age and health status with a T2 N2 HR-positive, HER2-negative breast cancer. Treatment options included chemotherapy and endocrine therapy, endocrine therapy alone, or no therapy. Respondents (n = 151) were further asked to specify use of either tamoxifen or aromatase inhibitors. A generalized linear mixed-effects model was used to determine the effect of age and health status on recommendations.ResultsAs the hypothetical patient's age increased or health status deteriorated, oncologists (n = 151) were less likely to recommend a combination of chemotherapy and endocrine therapy (P < .0001 for both). In contrast, oncologists were more likely to recommend endocrine therapy alone with advanced age and deteriorating health status (P < .0001 for both). Oncologists were more likely to choose treatment with aromatase inhibitors as opposed to tamoxifen (P < .01), irrespective of age or health status.ConclusionWith increasing age and declining health status, oncologists were more likely to recommend endocrine therapy alone as opposed to chemotherapy with endocrine therapy. Oncologists were most likely to recommend aromatase inhibitors, irrespective of age or health status.  相似文献   
60.
OBJECTIVES: Information technology is a rapidly expanding branch of science which has affected other sciences. One example of using information technology in medicine is the Electronic Medical Records system. One medical university in Iran decided to introduce such system in its hospital. This study was designed to identify the factors which influence the quality of medical documentation when paper-based records are replaced with electronic records. METHODS: A set of 300 electronic medical records was randomly selected and evaluated against eleven checklists in terms of documentation of medical information, availability, accuracy and ease of use. To get the opinion of the care-providers on the electronic medical records system, ten physicians and ten nurses were interviewed by using of semi-structured guidelines. The results were also compared with a prior study with 300 paper-based medical records. RESULTS: The quality of documentation of the medical records was improved in areas where nurses were involved, but those parts which needed physicians' involvement were actually worse. High workloads, shortage of bedside hardware and lack of software features were prominent influential factors in the quality of documentation. The results also indicate that the retrieval of information from the electronic medical records is easier and faster, especially in emergency situations. CONCLUSIONS: The electronic medical records system can be a good substitute for the paper-based medical records system. However, according to this study, some factors such as low physician acceptance of the electronic medical record system, lack of administrative mechanisms (for instance supervision, neglecting physicians and/or nurses in the development and implementation phases and also continuous training), availability of hardware as well as lack of specific software features can negatively affect transition from a paper-based system to an electronic system.  相似文献   
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