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11.
1. Spike generation by stimulation of the parafascicular nucleus of thalamus was extracellularly recorded in the nucleus accumbens of chloral hydrate-anesthetized adult Wistar rats using a silver-wire microelectrode attached along a seven-barreled micropipette, each of which was filled with dopamine, SKF 38393 (D-1 agonist), bromocriptine (D-2 agonist), haloperidol, SCH 23390 (D-1 antagonist) and domperidone (D-2 antagonist). The drugs were microiontophoretically applied to the target neurons recorded. 2. Effects of dopamine receptor antagonists on the inhibition of the spike generation by conditioning stimuli applied to the ventral tegmental area preceding the test stimulus to the parafascicular nucleus and those of dopamine agonists on the test stimulus-induced spikes were examined. 3. The parafascicular nucleus stimulation-induced spikes were inhibited by dopamine as well as D-1 and D-2 agonists and by the conditioning stimulation of the ventral tegmental area. The conditioning stimulation-induced inhibition was antagonized by haloperidol and SCH 23390, but not by domperidone. 4. Activation of D-1 receptors, which make probably synaptic contact with dopaminergic nerve terminals from the ventral tegmental area, is considered to result in inhibition of the neuronal activity of the nucleus accumbens neurons receiving input from the parafascicular nucleus of the thalamus. In addition, D-2 receptors located extrajunctionally may be involved in the inhibition of the same neurons in the nucleus accumbens.  相似文献   
12.
Scorpion venoms are composed of a number of neurotoxic peptides. A variety of toxins have been isolated from the venoms of scorpions of the family Buthidae, however, little interest has been paid to non-Buthidae scorpions. In this study, we examined the toxicity of the venom of Liocheles australasiae (Hemiscorpiidae) to mice and crickets, and characterized the peptide components by HPLC and mass spectrometry. Over 200 components were detected in the L. australasiae venom by LC/MS analysis, with components of molecular masses ranging from 500 to 5000 Da being particularly abundant. A number of peptides contained two to four disulfide bridges, which was estimated based on the mass difference after derivatization of Cys residues. A peptide having a monoisotopic molecular mass of 7781.6 Da and four disulfide bridges was isolated from the venom. The peptide has a primary structure similar in terms of the position of eight Cys residues to those observed in several peptides found from scorpions, ticks and insects, although biological roles of these peptides are unknown.  相似文献   
13.
BACKGROUND: The objective of this study was to evaluate the clinical outcome after surgical management of renal cell carcinoma (RCC) extending to the inferior vena cava (IVC). METHODS: This study included a total of 55 patients (41 men and 14 women; mean age, 59.3 years) with RCC (39 right- and 16 left-sided tumors) involving the IVC, who underwent radical nephrectomy and tumor thrombectomy between 1983 and 2005 at a single institution in Japan. The level of thrombus was classified as follows: level I, infrahepatic; level II, intrahepatic; level III, suprahepatic; and level IV, extending to the atrium. Clinicopathological data from these patients were retrospectively reviewed to identify factors associated with survival. RESULTS: There were 11 and 18 patients who were diagnosed as having lymph node and distant metastases, respectively. Twenty-two patients had tumor thrombus in level I, 20 in level II, 10 in level III, and 3 in level IV. Pathological examinations demonstrated that 34 and 21 patients had clear cell carcinoma and non-clear cell carcinoma, respectively, 42, 9 and 4 were pT3b, pT3c and pT4, respectively, and 6, 35 and 14 were Grades 1, 2 and 3, respectively. Cancer-specific 1-, 3- and 5-year survival rates of these 55 patients were 74.5%, 51.4% and 30.3%, respectively. Among several factors examined, clinical stage (P = 0.047), lymph node metastasis (P = 0.016), histological subtype (P = 0.034) and tumor grade (P < 0.001) were significantly associated with cancer-specific survival by univariate analysis. Furthermore, multivariate analysis demonstrated clinical stage (P = 0.037) and tumor grade (P < 0.001) as independent predictors of cancer-specific survival irrespective of other significant factors identified by univariate analysis. CONCLUSIONS: In patients with RCC involving the IVC, biological aggressiveness characterized by tumor grade rather than tumor extension would have more potential prognostic importance; therefore, more intensive multimodal therapy should be considered in patients with high grade RCC with tumor thrombus extending into the IVC.  相似文献   
14.
BACKGROUND: The objective of this study was to evaluate the efficacy and safety of first-line high-dose chemotherapy (HDCT) combined with peripheral blood stem cell transplantation (PBSCT) for patients with advanced extragonadal germ cell tumors (EGGCT). METHODS: Six male patients with advanced non-seminomatous EGGCT were treated with HDCT combined with PBSCT following 2-3 cycles of conventional-dose induction chemotherapy. The regimens used for HDCT were carboplatin, etoposide and ifosfamide (ICE) in five patients and ICE plus paclitaxel (T-ICE) in one patient, and that for induction therapy was cisplatin, etoposide and bleomycin (PEB) in all patients. As a rule, HDCT was continuously administered until alpha-fetoprotein (AFP) and beta-human chorionic gonadotropin normalized (beta-HCG). RESULTS: Following 1-6 courses of HDCT (median, 4 courses), beta-HCG and AFP were normalized in all patients, and five and one patient were diagnosed as showing partial remission and stable disease, respectively. Five patients underwent surgical resection of residual tumors after HDCT, yielding necrotic tissue in two, mature teratoma in two, and viable cancer tissue in one, and the surgical margin was negative in all patients. At a median follow-up of 36 months, five patients were alive and disease-free, whereas the remaining one died of disease progression. Although all patients had grade 3 hematological toxicity, there was no treatment-related death by combining PBSCT. CONCLUSIONS: First-line HDCT with PBSCT could be safely administered to patients with advanced EGGCT, and the antitumor effect of this treatment was comparatively favorable. First-line HDCT therefore may represent an attractive option for patients with advanced EGGCT.  相似文献   
15.
OBJECTIVE: Standard chemotherapy shows relatively low long-term survival in patients with poor-risk testicular germ cell tumor (GCT). First-line high-dose chemotherapy (HD-CT) may improve the result. High-dose carboplatin, etoposide, ifosfamide chemotherapy followed by autologous peripheral blood stem cell transplantation (PBSCT) was investigated as first-line chemotherapy in patients with advanced testicular GCT. METHODS: Fifty-five previously untreated testicular GCT patients with Indiana 'advanced disease' criteria received three cycles of bleomycin, etoposide and cisplatin (BEP) followed by one cycle of HD-CT plus PBSCT, if elevated serum tumor markers were observed after three cycles of the BEP regimen. RESULTS: Thirty patients were treated with BEP alone, because the tumor marker(s) declined to normal range. Twenty-five patients received BEP and HD-CT. One patient died of rhabdomyolysis due to HD-CT. Three and six (13% and 25%) out of 24 patients treated with BEP and HD-CT achieved marker-negative and marker-positive partial responses, respectively. The other patients achieved no change. Fifteen (63%) are alive and 14 (58%) are free of disease at a median follow-up time of 54 months. Severe toxicity included treatment-related death (4%). CONCLUSIONS: HD-CT with peripheral stem cell support can be successfully applied in a multicenter setting. HD-CT demonstrated modest anticancer activity for Japanese patients with advanced testicular GCT and was well tolerated. This regimen might be examined for further investigation in randomized trials in first-line chemotherapy for patients with poor-risk testicular GCT.  相似文献   
16.
17.
A new method of determining urinary polyamine concentration was compared with other techniques, namely, high pressure liquid chromatography (HPLC) and a polyamine test-enzyme kit. The values obtained by the new method, HPLC, and polyamine test-enzyme kit correlated well for all the fractions: diamine, spermidine and spermine. The correlation between the new method and the polyamine test-enzyme kit gave r = 0.9702, y = 1.1359x + 5.1266 (n = 48).  相似文献   
18.
Using high resolution ultrasonography (US), diagnostic accuracy of thrombi in each venous segment of lower limbs and qualitative evaluation of thrombi in deep vein thrombosis (DVT) were investigated. The subjects were 106 lower limbs in 81 patients. The thrombi in common femoral vein (CFV), were diagnosed by compression technique and, were qualitatively analysed by echogenicity and consistency. Venography was performed in 18 limbs and histologic tests of thrombi were made in 6 limbs. The total accuracy of US was 100% for diagnosis of DVT, but was 83% for diagnosis of its extent. The total accuracy of US in each segment was greater than 90%, but the sensitivity of iliac veins was less than 90%. The thrombi in CFV were divided into 3 types and 8 sub-types. Type A was homogenous, type B was heterogenous, and type C was contracted echo. The types of us were consistent with results of histologic tests. We concluded that high resolution US is available for screening test for diagnosis of DVT and that qualitative evaluation of thrombi by US is a useful clinical test for selection of more adequate treatments.  相似文献   
19.
Two cases of skullbase-penetrating injuries caused by umbrella tips are reported. Case 1: 24-year-old male. Admitted with disturbance of consciousness, left hemiparesis, nasal bleeding, and laceration of left lower eyelid because of having been stabbed by an umbrella tip. Pupils and fundi revealed no definite findings. Plain skull X-ray showed turbid ethmoid sinus and fracture of planum sphenoidale. Cranial CT showed right putaminal hematoma with intraventricular hemorrhage and pneumocephalus. Increased ICP necessitated surgery two days after the injury. Dural laceration of planum sphnoidale, laceration of left optic nerve, right rectal gyrus contusion and rebleeding from the right lenticulostriate branch were observed. Dural plasty and removal of hematoma with external decompression were carried out. He had a good postoperative course, but left visual loss and left hemiparesis remained. Case 2: 29-year-old male. Admitted with excoriation of his right nostril because of having been stabbed by an umbrella tip, severe headache, and nasal discharge. Oculomotor palsy was observed as well as CSF rhinorrhea and meningeal irritability. Plain skull X-ray showed niveau in sphenoidal sinus, pneumocephalus, and fracture of sella turcica. His complaint disappeared after conservative therapy. We reviewed the literature and found only 4 similar cases. The skullbase, because of its anatomical character, is likely to be penetrated in orbital and periorbital injury caused by umbrella tips. Cases which include disturbance of consciousness have a poor prognosis. We hope the fact that umbrella tips can easily become life-threatening objects will come to the attention of the general public so that similar cases may be avoided.  相似文献   
20.
Conclusion Reviewing the history of diagnostic procedures of causative organisms of respiratory infections, invasive techniques such as the protected specimen catheter (PSB) and bronchoalveolar lavage (BAL) have become the preferred choices because they have many advantages. These methods cause the patient relatively little discomfort, and permit an early diagnosis since they can easily be performed at the bedside and the causative organism from the disease site is obtained in cultures. These procedures can be used not only in patients with community-acquired lung infections, but also in immunocompromised hosts, including those with blood diseases or following renal transplantation, in patients in intensive care units and in mechanically-ventilated patients so that the cause can be accurately determined and chemotherapy started quickly, resulting in better therapeutic efficacy. Although these invasive procedures are advantageous for the diagnosis of respiratory infections, they also present various problems which remain to be addressed including minimizing contamination and setting diagnostic threshold values. However, the importance of accurately determining the causative organism in respiratory infections should be recognized as the most important factor, and these methods have shown to date to provide the most accurate information to aid in the timely treatment of respiratory infections in a wide variety of patients.  相似文献   
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