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41.
Cases of human diphyllobothriasis have been reported worldwide. Only 1 case in Brazil was diagnosed by our institution from January 1998 to December 2003. By comparison, 18 cases were diagnosed from March 2004 to January 2005. All patients who became infected ate raw fish in sushi or sashimi.  相似文献   
42.
Perineal hernia (PH) is formed by the protrusion of intra-abdominal viscera through a defect in the pelvic floor. This is a rare complication after conventional abdominoperineal resection, pelvic exanteration, proctectomy, and other pelvic procedures. The purpose of the present paper is to report 4 cases of PH after laparoscopic abdominoperineal resection for rectal cancer and to review literature data about the incidence, predisposing factors, and treatment of this challenging problem. When added to other 3 cases previously reported in the Brazilian series of laparoscopic surgery, this group of 7 cases comprises a PH incidence of 3.5% after rectal resection procedures. Surgical treatment is indicated only in symptomatic patients with no signs of cancer recurrence. Proposed methods of surgical repair include abdominal, perineal, or combined approaches to the hernia in association with the use of autologous tissues or prosthetic meshes. Preventive measures are represented by closure of the pelvic peritoneum whenever possible, primary perineal suture and wound care to avoid infection.  相似文献   
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Oral mucositis is a frequent side-effect of cancer therapy. A definitive method of prophylaxis or treatment is not yet available. As pentoxifylline (PTX) and thalidomide (TLD) have been shown to inhibit cytokine synthesis, we studied the effects of these cytokine inhibitors in an experimental oral mucositis model. Oral mucositis was induced in Golden hamsters by the administration of 5-fluorouracil (5-FU) followed by mechanical trauma of the cheek pouch. On days 4, 5, 10, 12, 14 and 16, lesions induced by 5-FU were examined macroscopically and microscopically, and the presence and intensity of hyperemia, erythema, edema, inflammatory cell infiltration, hemorrhagic areas, ulcers and abscesses were recorded. Saline (control), PTX (5, 15, 45 mg kg(-1)) or TLD (10, 30, 90 mg kg(-1)) were administered daily and animals were killed on day 10 for macroscopic and histological analysis and assay of myeloperoxidase (MPO) activity. Animals were weighed daily, and total and differential leukocyte counts were performed on peripheral blood. PTX and TLD were found to reduce the macroscopic and histological parameters of oral mucositis and MPO activity. PTX and TLD also reversed peripheral neutrophilia, but only PTX prevented weight loss. The results indicate a protective effect of PTX and TLD, suggesting an important role for tumour necrosis factor-alpha (TNF-alpha) in the pathophysiology of 5-FU induced-oral mucositis in hamsters.  相似文献   
45.
BACKGROUND: Acyclovir (ACY) is a useful therapeutic agent for the systemic treatment of herpes virus infection. An increase in urinary phosphate excretion and polyuria has been described. The objective of this study was to analyze the exact mechanism of the urinary-concentrating dysfunction and the increase in phosphaturia associated with ACY. METHODS: We first analyzed 7 (adult and pediatric) non-AIDS cases of encephalitis receiving 15 mg/kg bw/d of intravenous ACY. Fractional phosphate and sodium excretion, urinary potassium volume, and plasma phosphate concentrations were analyzed. Additional studies in rats treated with intraperitoneal ACY (100 mg/kg bw) were also conducted. Animals were maintained in metabolic cages and 24-hour urine samples were collected to measure volume, osmolality, and sodium/potassium/phosphate excretion. Treated rats were also evaluated after 24 hours and 48 hours of water deprivation. Northern hybridization and semiquantitative immunoblotting were performed to evaluate (in both control and treated animals) expression of the cotransporters Na-Pi type IIa (Na-Pi-IIa) and Na-K-2Cl (NKCC2). Semiquantitative immunoblotting was carried out in the kidneys of ACY rats and control rats in order to analyze aquaporin 2 (AQP2) protein expression. RESULTS: Patients started on ACY developed polyuria and hyperphosphatemia after 48 hours. In rats, ACY-induced hyperphosphaturia and hypophosphatemia were accompanied by increased excretion of sodium, potassium, and magnesium, increased urine output, lower urinary osmolality, and a partial urinary concentrating defect. Concurrent downregulation of Na-Pi-IIa and NKCC2 expression was observed. There was also a decrease in medullar expression of the AQP2 collecting duct water channel. CONCLUSION: Downregulation of Na-Pi-IIa appears to play a crucial role in the downregulation of ACY-induced hyperphosphaturia. The accompanying polyuria and urinary-concentrating defect can in part be explained by the downregulation of NKCC2 and AQP2.  相似文献   
46.
Sodium saccharin (NaS) and calcium cyclamate (CaC) are artificial sweeteners widely used in food and drink. To evaluate their toxicological effects on preimplantation mammalian embryos, pregnant rats were gavaged with 1.65 mg NaS/kg bw + 3.85 mg CaC/kg bw (DI) or 6.6 mg NaS/kg bw + 15.4 mg CaC/kg bw (D2) on days 1, 2, 3 and 4 of pregnancy (positive vaginal smear = day 1). The female rats were killed on day 5 of the pregnancy (GD 5), maternal organs weighed, and the blastocysts collected, counted and evaluated for gross morphology, cell number and mitotic index. There was no alteration in maternal organ weights, but there was an increase of the cell number/embryo in the dams treated with that NaS + CaC mixtures (D1 = 37.20 +/- 7.96; D2 = 37.26 +/- 10.90) compared to control group (32.24 +/- 6.73). Embryos whose dams were exposed to NaS + CaC may have adapted for implantation into the uterus but more studies are needed to demonstrate this mechanism of action.  相似文献   
47.
Small-cell lung cancer (SCLC) accounts for 20%-25% of all new cases of lung cancer and represents the sixth most commonly diagnosed cancer in the United States. Given the tumor's systemic nature and chemoresponsiveness, chemotherapy has become the cornerstone of its management. Chemotherapy significantly prolongs survival; however, most of the patients still die within 2 years of diagnosis. Combination chemotherapy represents the treatment of choice for this disease. In the United States, cisplatin/etoposide is the regimen most frequently used for the first-line therapy of SCLC patients because of its better therapeutic index. Upon recurrence, topotecan is the Food and Drug Administration-approved treatment based on a phase III trial that showed no statistically significant differences in survival or response for topotecan compared with CAV (cyclophosphamide/doxorubicin/vincristine) but a better disease-related symptom improvement compared to baseline favoring the topoisomerase I inhibitor. Newer agents, with novel mechanisms of action, have shown activity against SCLC and are being tested in many different combinations. Among these agents, gemcitabine has attractive mechanisms of action and toxicity profile. Gemcitabine is a pyrimidine nucleoside antimetabolite, analogue to cytosine arabinoside, which through incorporation into the DNA leads to inhibition of DNA synthesis and cytotoxicity. As a single agent, gemcitabine has modest activity against SCLC. However, like with many other drugs, response rates improve when gemcitabine is used in combination regimens. Phase II and III studies of combinations with classic drugs for the management of SCLC patients such as cisplatin and/or etoposide and gemcitabine demonstrate comparable results to those of standard therapies. The gemcitabine/paclitaxel and gemcitabine/topoisomerase I inhibitor combinations are also of great interest, and preliminary results in previously treated patients are promising. The proper role of gemcitabine in the treatment of patients with SCLC awaits future testing in randomized phase III trials.  相似文献   
48.
Hemophilia is an important hemorrhagic disease in Brazil, affecting about 1 out of every 10,000 males. Patient's self-perception of hemophilia and interaction with the community are relevant to the clinical management of this disease. We investigated several social, psychological, and community aspects of hemophilia in a Brazilian population (Campinas, S?o Paulo State), interviewing 30 hemophiliac males, a control sample comprised of 73 non-hemophiliac brothers, and 641 individuals from the community. According to our results, more severe social disability in the hemophiliac patient was related to economic factors, mainly unemployment; however, no difference was found in relation to marital status, reproduction, or education. Self-perception of changes in health and lifestyle by individuals with hemophilia showed frequent self-stigmatization, along with depression, anxiety, and insecurity. The community showed a widespread lack of familiarity with hemophilia (49%), viewing people with hemophilia with the kinds of prejudices often observed in relation to people with infectious diseases, like AIDS. The paper concludes by recommending that a community-based program be implemented to improve the social adjustment status of individuals with hemophilia.  相似文献   
49.
CONTEXT: Highly active antiretroviral therapy (HAART) has turned human immunodeficiency virus (HIV) infection into a chronic condition, and this has led to increased incidence of anal dysplasia among HIV-positive patients. Routine anal evaluation including the anal canal and perianal area is recommended for this population, especially for patients infected by oncogenic human papillomavirus (HPV) types. CASE REPORT: A 54-year-old homosexual HIV-positive man presented with a six-year history of recurrent perianal and anal warts. He had previously undergone incomplete surgical excision and fulguration in another institution on two occasions. He had been using HAART over the past two years. He presented some condylomatous spreading lesions occupying part of the anal canal and the perianal skin, and also a well-demarcated slightly painful perianal plaque of dimensions 1.0 x 1.0 cm. Both anal canal Pap smears and biopsies guided by high-resolution anoscopy revealed high-grade squamous intraepithelial lesion. Biopsies of the border of the perianal plaque also revealed high-grade squamous intraepithelial lesion. HPV DNA testing of the anus detected the presence of HPV-16 type. The patient underwent local full-thickness excision of the lesion. Histological analysis on the excised tissue revealed high-grade squamous intraepithelial lesion with one focus of microinvasive squamous cell cancer measuring 1 mm. No lymph vessel or perineural invasion was detected. The patient showed pathological evidence of recurrent anal and perianal high-grade squamous intraepithelial lesions at the sixth-month follow-up and required further ablation of those lesions. However no invasive squamous cell carcinoma recurrence has been detected so far.  相似文献   
50.
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