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Retraction pockets of the tympanic membrane are believed to be due to eustachian tube obstruction or malfunction. Our observations based on intraoperative findings suggest that the presence of a large sized mastoid antrum along with chronic eustachian tube obstruction plays an important role in the causation of retraction pockets. Granular myringitis may also occur in these circumstances when there is a recurrent eustachian tube blockage due to infection especially if the patient has received frequent and inadequate courses of antibiotics. The use of chromic catgut to create a healed air-filled middle ear space along with a canal wall down tympanomastoidectomy is discussed for their effective treatment.  相似文献   
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The Cd40 ligand     
For several years, the primary function of CD40 ligand (CD40L) has been believed to be in regulation of contact-dependent, CD40-CD40L-mediated signals between B-and T-cells, which are essential for the regulation of thymus-dependent (TD) humoral immune responses. Recently, a flurry of reports indicate that CD40 is expressed by variety of cell types other than B-cells that include dendritic cells, follicular dendritic cells, monocytes, macrophages, fibroblasts, and endothelial cells. These studies show that CD40-CD40L interactions are important in inflammatory process. For the past few years, through the availability of CD40L-knockout mice, new data have emerged to support the belief that CD40L has many more functions than its role in TD humoral immunity. CD40L-deficient mice have provided significant information towards our understanding of the in vivo role of CD40L. The current picture that emerges indicates that CD40-CD40L interactions mediate many cell-mediated immune responses and T-cell-mediated effector functions that are required for proper functioning of the host defense system. This article focuses on the in vivo role of the CD40L in regulation of cell-mediated effector functions.  相似文献   
4.
M Ahuja  J Wig  S Grewal  MS Dhillon 《The Knee》1995,2(4):227-231
In a prospective, double blind, randomized study, 30 ASA I patients were allocated to three groups depending on the drug injected intra-articularly, in an attempt to establish the best postoperative analgesic protocol following knee arthroscopy. Group 1 received 3 mg of preservative-free morphine in 25 ml saline; group 2, 5 mg of preservative-free morphine in 25 ml saline; and group 3, 25 ml 0.25% bupivacaine. The degree of postoperative pain was evaluated by visual analogue scale and the need for additional analgesics at 1, 2, 3, 8 and 24 h. We conclude that bupivacaine 0.25% provides analgesia of early onset and of short duration. While 3 mg-preservative free morphine provides moderate postoperative analgesia with peak effect during the eighth postoperative hour, 5 mg preservative-free morphine provides effective and long lasting (more than 24 h) pain relief. No side effects were noted.  相似文献   
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A prospective, randomised, single blind study was conducted to evaluate and compare the intracranial pressure (ICP) and cardiovascular effects of pipecuronium (PPC) and pancuronium (PNC) in 20 patients undergoing supratentorial surgery. Patients were randomly divided into two groups. Patients in Group I (n = 10) received pancuronium (0.1 mg kg(-1)) and in Group II (n = 10) pipecuronium (0.07 mg kg(-1)) for intubation. Intracranial pressure (ICP), heart rate (HR), systolic, diastolic and mean arterial pressures (SAP, DAP, MAP), central venous pressure (CVP), nasopharyngeal temperature and arterial blood gases (ABG) were monitored at the following time periods: before induction (0 minutes); 3 minutes after thiopentone and muscle relaxant; immediately after intubation; and 4, 6, 8, 10, 20 and 30 minutes following intubation. The rise in intracranial pressure at intubation was significantly greater in group I (21.10+/-3.97 torr, 122.59%) when compared to group II patients (1.80+/-0.70 torr, 10.04%) (p<0.0 1). Cardiovascular parameters also showed a significantly greater degree of rise in group I when compared to group II patients. Heart rate increased by 29+/-6.32 beats min(-1) (33.52%) and systolic arterial pressure by 11.60+/-7.37 torr (9.47%) in group I. These parameters did not change significantly in group II. No significant alterations were observed in the other measured parameters in either of the two groups.  相似文献   
6.
Retractions of the tympanic membrane constitute a large proportion of ear diseases causing concern to the otologist. The clinical features in a case of retraction pocket are varied and cholesteatoma. Also, that a retraction pocket in the posterosuperior region and pars ftaccida is a precursor of cholesteatoma is now well recognized. We have studied 60 cases of retraction pockets during a period of 5 years and have attempted to find out the etiology as well as the most effective treatment in such cases. Though over the years along with a dysfunctional eustachian tube, a sclerotic mastoid has been implicated as one of the causes of Retraction Pockets, we in our study have seen a large sized mastoid antrum (beyond 2 mm vf Lateral Semicircular Canal) as a consistent feature in most of our cases. This was subjectively assessed as a surgical finding in tympanomastoidectomy and objectively assessed by a high Resolution Computed Tomography of the temporal bone. We have found that a canal wall down mastoidectomy was the most effective in preventing the recurrence of retraction pockets. In a coutry like India, canal wall down mastoidectomy offers an acceptable solution to the problem of retraction pocket as not only is the follow up of patients poor but also the “Second- Look” procedure is not always possible. The use of 1- 0 chromic catgut in the middle ear instead of the more conventionally used silastic in preventing recurrent retractions can be considered as an effective single-staged procedure.  相似文献   
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Human neutrophils treated with pertussis toxin had decreased functional responses to several agents including zymosan-treated serum, heat-aggregated immunoglobulin, platelet-activating factor, and fMet-Leu-Phe. Responses affected include superoxide generation and release of lysozyme. The degree and type of inhibition was dependent on the individual receptor and the cellular response studied. Measurement of intracellular calcium levels with quin-2 showed that both fMet-Leu-Phe- and platelet-activating factor-mediated increases in quin-2 fluorescence were diminished as a result of pertussis toxin treatment. fMet-Leu-Phe-mediated calcium uptake was also inhibited. However, under conditions where fMet-Leu-Phe-mediated effects on cell function were completely abolished, only a partial inhibition of 3,4,5-trimethoxybenzoic acid 8-(diethylamino)octyl ester (TMB-8) sensitive calcium uptake was observed. A study of the linked reactions of chemotaxis, capping, and shape change revealed that chemotaxis was inhibited regardless of the chemoattractant utilized (zymosan-treated serum, fMet-Leu-Phe, and platelet-activating factor) and the associated reactions of Con A capping and fMet-Leu-Phe- or Con A-mediated shape change were reduced in pertussis toxin-treated cells. Our results suggest that multiple mediators of inflammation act through a pertussis toxin-sensitive GTP-binding protein that regulates the mobilization of internal calcium as well as calcium uptake and is, in addition, a key control element of shape change, capping, and chemotaxis.  相似文献   
10.
BACKGROUND: Laparoscopic surgery has reduced the length of hospital stay for common operations like cholecystectomy, gastric fundoplication, and appendectomy. We have noticed a reduction in length of hospital stay for children undergoing laparoscopic appendectomy. We, therefore, looked at our data to assess whether laparoscopic appendectomy in children could be performed as fast-track or same-day surgery (< or = 24-hour postoperative stay). METHODS: We performed a retrospective review of the records of all children who underwent laparoscopic appendectomy for suspected appendicitis during a 3-year period (7/97 to 7/00). RESULTS: Laparoscopic appendectomy was performed in 79 children (44 boys and 35 girls), between 2 to 17 years of age (mean, 11 years). In 4 (5%) children with perforated appendicitis, the laparoscopic appendectomy was converted to an open appendectomy. At operation, 51 (64.5%) had acute appendicitis, 22 (27.8%) had perforated appendicitis, 4 (5%) had ruptured ovarian cysts, and 2 (2.5%) had no pathology. The median operative time was 54 minutes. Total length of stay for all 79 patients was a median of 58 hours, and median postoperative LOS was 35 hours. Complications included wound infection (2), abdominal abscess (4), drug rash (2), and epididymo-orchitis (1). In 57 (72%) children without perforated appendicitis, the total length of hospital stay was a median of 42 hours, while median postoperative length of stay was only 28 hours. Thirty-two (56%) children went home in < or = 24 hours following laparoscopic appendectomy. No significant morbidity was noted in the nonperforated group (drug rash, 1 fever > 24 hrs, 3); and no readmissions or reoperations were necessary on follow-up. CONCLUSION: Laparoscopic appendectomy is safe and effective for treating children with appendicitis. Laparoscopic appendectomy may be safely performed as fast-track or same-day surgery, in select children without perforated appendicitis, with a postoperative stay of < or = 24 hours.  相似文献   
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