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991.
The purpose of this study was to investigate the association between prophylactic antibiotic administration (PAA) and post-operative infection in radical cystectomy with orthotopic neobladder urinary diversion carried out for patients with bladder cancer. Fifty-seven consecutive cases were analyzed retrospectively. Post-operative infections were categorized as urinary tract, wound, and remote infections. We used the antibiotics tazobactam/piperacillin (TAZ/PIPC), sulbactam/ampicillin (SBT/ABPC), flomoxef (FMOX), cefazolin (CEZ), cefotiam (CTM), and cefmetazole (CMZ). Twenty-five (43.9%) patients had post-operative infections. Five of these (8.77%) patients had wound infections, 22 (38.6%) patients had urinary tract infections, and 2 (3.51%) had remote infections. Our statistical analysis demonstrated that the patients with TAZ/PIPC used for PAA (5/18: 27.8%) had a significantly lower post-operative infection rate than patients with other antibiotics (24/39: 61.5%) (p = 0.0442). In addition, the patients with a shorter-duration PAA (within 72 h after the operation (48-72 h)) had a significantly lower rate of post-operative infections (12/33: 36.4%) than those with longer-duration PAA (longer than 72-96 h after the operation) (16/24: 66.7%) (p = 0.0239). Taken together, these results suggest that TAZ/PIPC with shorter PAA duration (within 72 h) might lead to a lower rate of post-operative infections. In conclusion, our data showed that PAA with TAZ/PIPC with a shorter duration PAA (within 72 h) might be recommended for radical cystectomy with orthotopic neobladder reconstruction. A prospective study based on our data is desirable to establish or revise guidelines for prophylactic medication for preventing post-operative infection after radical cystectomy with orthotopic neobladder urinary diversion.  相似文献   
992.
This study measured blood parameters, particularly those related to coagulation, and alterations in the expression levels of blood-coagulation-related genes in lactating Sprague-Dawley rats. The day of delivery was designated as lactation day 0 (LD 0). On the day after delivery (LD 1), prothrombin time and overall activity of vitamin-K-dependent coagulation factors were decreased, whereas fibrinogen contents, platelet counts and antithrombin III concentrations were increased as compared with those in nonpregnant rats. In addition, hepatic expression of blood-coagulation-related genes in the liver was increased at LD 0 as compared with that in nonpregnant rats. These changes may be physiologic responses to prevent prolonged bleeding at delivery. Except for fibrinogen content, which remained elevated, the described changes returned to baseline on and after LD 7. Activities of AST, ALT, and ALP were increased on LD 7, 14, and 21 as compared with nonpregnant rats. In contrast, total protein, albumin, Cl, and Ca were consistently lower on LD 7, 14, or 21 as compared with levels in nonpregnant rats. These results provide background data for evaluation of nursing rats.  相似文献   
993.
Rituximab (RTX) is effective for treating cancer, but reports of RTX-associated enterocolitis are limited. We herein report the case of a 65-year-old man who developed RTX-induced ileocolitis. He was diagnosed with gastric mucosa-associated lymphoid tissue lymphoma (MALToma) and treated with RTX. He complained of bloody diarrhea after RTX. Mucosal inflammation on colonoscopy indicated RTX-induced ileocolitis. He was treated with corticosteroids, and his symptoms improved. We reviewed the RTX-associated gastrointestinal adverse events and classified the features into ulcerative colitis, Crohn''s disease, microscopic colitis, and ileocolitis. To our knowledge, this is the first case of a Japanese patient who developed RTX-induced ileocolitis.  相似文献   
994.
Cholesterol crystal embolization (CCE) shows a poor prognosis and it can cause ischemic organ damage due to a cholesterol embolism from atherosclerotic lesions in large blood vessels. Such an embolism mainly affects the kidneys and skin, although cases involving digestive organs have also been reported. We encountered an autopsy case of CCE with damage mainly to the digestive organs, including the pancreas. The patient had non-specific abdominal symptoms or image findings. Symptomatic therapy failed to save him. CCE can involve the digestive organs, and so must be differentiated from abdominal pathologies. Moreover, conventional treatments may be ineffective, and new treatments might thus be necessary.  相似文献   
995.
The fine structural alteration in the gastric nerve fibers containing gastrin-releasing peptide (GRP) was studied in relation to the dynamics of gastrin-producing cells (G-cells) after truncal vagotomy in a rat model. The circulating gastrin levels were markedly elevated from the 1st day after vagotomy and the number of G-cells with positive immunoreaction for G17 and G34(1–15) was significantly increased in the vagotomized group. On the 3rd day after vagotomy, the G-cells showed conspicuous ultrastructural changes characterized by hypertrophy of the Golgi complexes and increased numbers of secretory granules. The GRP-positive nerve fibers formed a fine network in the gastric wall and were densely distributed in the oxyntic mucosa close to the blood vessels and showing varicosites composed of either small clear or GRP-positive large vesicles containing an electron-dense core. In the oxyntic mucosa of the vagotomized rats, axonal swelling of the nerves occurred on the 3rd day, and a depletion of GRP immunoreactivity was evidenced by a markedly decreased number of large-cored vesicles on the 7th day, when the serum GRP levels were also found to be markedly elevated. These findings indicate that the alteration in gastric nerve fibers containing GRP after truncal vagotomy may be related to hypergastrinemia and antral G-cell hyperplasia in the rat gastric mucosa.  相似文献   
996.
Background We treated nine patients with uncommon and high-risk extragonadal germ-cell tumors (EGCTs) between 1982 and 1991. Methods Anterior mediastinal lesions were located in five patients, retroperitoneal tumors in three patients, and in one patient both mediastinal and retroperitoneal tumors were found. Chemotherapeutic regimens consisted of cisplatin, vincristine, bleomycin and actinomycin D (PVcBA); cisplatin, vinblastine and bleomycin (PVB); vinblastine, actinomycin D, cyclophosphamide, bleomycin and cisplatin (VAB-6); and bleomycin, etoposide and two doses of cisplatin (high-dose BEP). Results Two patients receiving PVcBA and second-line chemotherapy showed partial responses. Six patients; one treated with PVB, two with VAB-6, and three others with high-dose BEP with or without additional chemotherapy, underwent surgical resection of residual tumors. Histologic examinations showed either necrotic debris or necrosis including mature teratoma (complete response). In one patient, whose tumor marker was negative, unresectable residual tumors continued to shrink and disappeared with no maintenance therapy following administration of high-dose BEP. Overall, 7 of 9 patients (77.8%) achieved a complete response to either chemotherapy alone or a combination of chemotherapy and surgery. One patient, who suffered a relapse from an apparent CR, was also treated successfully. These patients remain disease free. Conclusion Patients with EGCTs are curable, even if the tumors in question are in highly advanced stages, as long as appropriate chemotherapy and surgical resection are undertaken in a timely fashion.  相似文献   
997.
The effects of timing of a single intragastric application of dibutyltin dichloride, at a dosage of 30 mg/kg body wt, on N-nitrosobis(2-oxopropyl)amine (BOP)-induced pancreatic carcinomas have been studied in female Syrian golden hamsters. Dibutyltin dichloride, which has been shown to produce selected bile duct injury, was administered either 1 week before or 1 week after a single injection of BOP (20 mg/kg body wt). Control hamsters were injected with BOP alone or were given dibutyltin dichloride alone. The incidence of ductal adenocarcinomas strikingly decreased in hamsters when dibutyltin dichloride was ingested after BOP treatment, but remained unaffected when dibutyltin dichloride was given before carcinogen treatment. Two cases of sarcoma were observed in the group treated with dibutyltin dichloride before BOP injection. The incidence of insulomas, which were considered as spontaneous tumors, was not influenced by dibutyltin dichloride. These results showed that intragastric application of dibutyltin dichloride after BOP treatment significantly reduced the induction of pancreatic cancer. These findings do not support speculations based on epidemiologic studies as to a promoting effect of cholestasis.  相似文献   
998.
Four cases of anaplastic carcinoma of the thyroid, composed of one small cell carcinoma and three giant cell carcinomas, were studied with electron microscope. In the case of small cell carcinoma, fine cytoplasmic interdigitations and junctional complex between apposing cytoplasmic membranes of neighbouring tumor cells and a few microlumina within tumor cell clusters surrounded by well-defined basal lamina were seen. In the cases of giant cell carcinoma, occasional cytoplasmic interdigitations as well as desmosomal structures were detected even in tumor cells markedly pleomorphic and anaplastic. Abundant cytoplasmic organelles including profiles of Golgi apparatus, rough endoplasmic reticulum and a few mitochondria were seen in the cytoplasm of tumor cell of all four cases. Of interest to note was that all giant cell carcinomas demonstrated evidences of fairly well differentiated tumor within anaplastic carcinoma, indicating probable pre-existing either benign or malignant epithelial neoplasm more differentiated, with its subsequent anaplastic trasformation. Findings in the present study support an assumption that these anaplastic tumors are derived from the follicular epithelium of the thyroid gland. In addition, it can be said that tumor cells of the small cell carcinoma provide evidences suggesting functional differentiation of carcinoma cells to a certain extent, yet unable to produce thyroglobulin.  相似文献   
999.
The potential liver-tumor-initiating activity of acetaminophen(paracetamol, APAP) was investigated in male F344 rats. APAPwas administered by intragastric intubation either as 10 dosesof 1 g/kg body weight over 5 weeks or as a single dose of 0.5g/kg body weight 24 h after two-thirds partial hepatectomy.These initiating treatments were followed by administrationof 0.1% phenobarbital in the drinking water for 12 weeks asthe promoting regimen. Quantitative examination of placentalglutathione S-transferase-positive foci revealed no enhancingeffect of APAP on the induction of the foci consisting of morethan two positive cells with either initiating treatment. Ifsolitary positive hepatocytes were included in the effectivenumber of foci, 10 repeated doses of 1 g/kg APAP increased thenumber of foci while the validity of the single positive cellsis uncertain. This dose of APAP caused centrilobular necrosis.By 32P-postlabeling, although the active metabolite of APAPformed DNA adducts when incubated with isolated DNA, no DNAadduct formation was detected in the liver of rats either fed0.1–1.5% APAP for 1 week or given 1 g/kg by gastric intubation.These results indicate that APAP possesses no tumor-initiatingactivity in the rat liver.  相似文献   
1000.
Pneumotoxicity of butylated hydroxytoluene applied dermally to CD-1 mice   总被引:1,自引:0,他引:1  
Pneumotoxicity of butylated hydroxytoluene (BHT) applied to the skin of CD-1 mice was investigated and compared with that of butylated hydroxyanisole (BHA). To 6 groups of 10 male mice and 10 female mice 0.1 ml of dimethylsulfoxide (DMSO) solutions containing 0, 5, 10, 20, or 30 mg of BHT or 30 mg of BHA were topically applied 3 times weekly for 4 weeks. Between the 4th and 8th day BHT-treated mice exhibited respiratory distress with subsequent dose-dependent mortality. At autopsy dead animals were found to have congestion and enlargement of the lung with oozing of froth from the trachea. Histologically, collapse of the alveoli and dilatation of the alveolar ducts associated with degeneration or necrosis of type I alveolar epithelial cells were evident. The lethal effect of BHT was more manifest in female than in male mice. In contrast, none of the BHA-treated or control mice showed lung abnormalities. In another series of experiments to study the species difference of BHT pneumotoxicity, F-344 rats of both sexes and male Syrian golden hamsters were exposed to BHT by dermal application 3 times weekly for 4 weeks at a dose of 240 mg in rats or 480 mg in hamsters. However, no pulmonary alterations were observed in either species.  相似文献   
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