全文获取类型
收费全文 | 4466篇 |
免费 | 308篇 |
国内免费 | 17篇 |
专业分类
耳鼻咽喉 | 66篇 |
儿科学 | 175篇 |
妇产科学 | 102篇 |
基础医学 | 726篇 |
口腔科学 | 110篇 |
临床医学 | 330篇 |
内科学 | 1154篇 |
皮肤病学 | 122篇 |
神经病学 | 371篇 |
特种医学 | 143篇 |
外科学 | 661篇 |
综合类 | 17篇 |
一般理论 | 3篇 |
预防医学 | 217篇 |
眼科学 | 105篇 |
药学 | 244篇 |
中国医学 | 11篇 |
肿瘤学 | 234篇 |
出版年
2023年 | 20篇 |
2022年 | 50篇 |
2021年 | 120篇 |
2020年 | 60篇 |
2019年 | 125篇 |
2018年 | 138篇 |
2017年 | 79篇 |
2016年 | 89篇 |
2015年 | 106篇 |
2014年 | 137篇 |
2013年 | 179篇 |
2012年 | 286篇 |
2011年 | 298篇 |
2010年 | 158篇 |
2009年 | 156篇 |
2008年 | 246篇 |
2007年 | 245篇 |
2006年 | 235篇 |
2005年 | 239篇 |
2004年 | 239篇 |
2003年 | 227篇 |
2002年 | 196篇 |
2001年 | 183篇 |
2000年 | 196篇 |
1999年 | 136篇 |
1998年 | 55篇 |
1997年 | 45篇 |
1996年 | 39篇 |
1995年 | 24篇 |
1994年 | 23篇 |
1993年 | 20篇 |
1992年 | 66篇 |
1991年 | 45篇 |
1990年 | 41篇 |
1989年 | 30篇 |
1988年 | 29篇 |
1987年 | 37篇 |
1986年 | 17篇 |
1985年 | 19篇 |
1984年 | 22篇 |
1983年 | 19篇 |
1982年 | 12篇 |
1979年 | 12篇 |
1977年 | 12篇 |
1976年 | 8篇 |
1975年 | 8篇 |
1973年 | 6篇 |
1971年 | 6篇 |
1970年 | 7篇 |
1968年 | 6篇 |
排序方式: 共有4791条查询结果,搜索用时 140 毫秒
51.
Lleonart R Riego E Saínz de la Peña MV Bacallao K Amaro F Santiesteban M Blanco M Currenti H Puentes A Rolo F Herrera L de la Fuente J 《International journal of legal medicine》2000,113(2):98-101
We report the positive identification of several members of the guerrillas led by Ernesto “Che” Guevara on the 1960 s in
Bolivia by means of DNA fingerprinting. Successful DNA typing of both short tandem repeat loci and the hypervariable region
of the human mitochondrial DNA was achieved after extracting total DNA from bones obtained from two burial sites. Given the
size of the Cuban database for the STR allele frequencies, a conservative approach was followed to estimate the statistical
significance of the genetic evidence. The estimated probabilities of paternity for the two cases in which the paternity logic
was applied were higher than 99%. One case was analyzed using mitochondrial DNA and could not be excluded from the identity
proposed by the forensic anthropology team. A fourth case was identified by exclusion, on the basis of the positive identification
of the other remains, the historical and other anthropological evidence.
Received: 19 January 1999 / Received in revised form: 15 April 1999 相似文献
52.
BACKGROUND: Glomerular filtration rate (GFR) in humans and animals might be determined with precision by measuring the clearance of an ideal marker, such as inulin. However, the use of inutest, an inulin analog, is limited by its cost and accessibility. The present study tested whether low calorie commercial sugar (LC sugar) can be used to measure GFR during normal and renal dysfunction. METHODS: Two groups of 6 male Wistar rats weighing 300 to 350 g were included. One group was treated with a daily dose of cyclosporine (CsA) 30 mg/kg subcutaneously for 7 days and the other group was formed by nontreated control rats. In one half of each group, GFR was evaluated by using inutest and in the other half by using LC sugar. GFR was also evaluated by using a wide LC sugar plasma concentration range in an additional group. RESULTS: In nontreated rats, the mean GFR evaluated with LC sugar was 2.2 +/- 0.1 mL/min. This value is equal to that obtained with inutest: 2.3 +/- 0.1 mL/min. CsA administration produced a significant reduction of renal blood flow and renal function. The GFR reduction induced by CsA was similarly determined by both LC sugar and inutest to be at 1.0 +/- 0.2 and 1.1 +/- 0.2 mL/min (P= NS), respectively. In addition, GFR did not change when LC sugar plasma concentration gradually increased. CONCLUSION: Our results show that in both normal and pathophysiologic conditions, LC sugar is a good marker of GFR similar to the gold standard inutest. 相似文献
53.
Asensio Llorente M López Espinosa JA Ortega López J Sánchez Sánchez LM Castilla Valdez MP Ferrer Blanco C Margarit Creixell C Iglesias Berengue J 《Cirugía pediátrica : organo oficial de la Sociedad Espa?ola de Cirugía Pediátrica》2003,16(1):44-47
Biliary atresia is the most common indication for liver transplantation in the pediatric age group. The Kasai portoenterostomy has become established as the primary treatment for biliary atresia. If portoenterostomy fails, death before 2 years of age is likely without liver transplantation. The most common multiple malformation syndrome associated with biliary atresia is polysplenia syndrome, which forms a constellation of defects of body symmetry, splenic development and vascular anomalies, including situs inversus, polysplenia and others. The situs inversus was formerly considered an absolute contraindication for liver transplantation. Recently however, several case reports have been published suggesting that neither situs inversus nor this particular subset of vascular abnormalities should be considered contraindications to liver transplantation. We present one case of liver transplantation performed in patient with biliary atresia, situs inversus and polysplenia. This is the first report described in Spain for a liver transplant in a child with biliary atresia plus situs inversus. 相似文献
54.
Since the first reports with laparoscopic resection of islet cell tumors in 1996, the experience worldwide is still limited,
with only short-term outcomes available. Some have suggested that a malignant tumor is a contraindication to laparoscopic
resection.
Aim The aim of this study was to evaluate the feasibility, safety, and long-term outcome of the laparoscopic approach in patients
with functioning, nonfunctioning, or overt malignant pancreatic neuroendocrine tumor (PNT). To our knowledge this is the largest
single-institution series on this subject to date.
Patients and methods A total of 49 consecutive patients (43 women, 6 men; mean age 58 years, range 22–83 years) underwent laparoscopic pancreatic
surgery (LPS) from April 1998 to June 2007. Preoperative localization was done by computed tomography, magnetic resonance
imaging, endoscopic ultrasonography, and Octreoscan imaging. Other than 9 PNTs localized in the head of the pancreas, all
tumors were located in the left pancreas. Malignancy was diagnosed based on the presence of lymph nodes or liver metastasis.
There were 33 patients with functioning tumors: 4 with gastrinomas (mean size 1.2 cm), 1 with a glucagonoma (4 cm), 3 with
vipomas (3.2 cm), 2 with carcinoids (5.2 cm), 20 with sporadic insulinomas (1.4 cm), 2 with insulinoma/multiple endocrine
neoplasia type 1 (MEN-1) (4.4 cm), and 1 with a malignant insulinoma (13 cm). Sixteen patients had a nonfunctioning tumor
(mean size 5 cm). The following techniques were performed: laparoscopic spleen-preserving distal pancreatectomy (Lap SPDP),
laparoscopic distal pancreatectomy with splenectomy (Lap SxDP) and laparoscopic enucleation (Lap En)/laparoscopic excision
(Lap E). Lymph node dissection was performed when malignancy was suspected (Strasberg′s technique). Evaluation criteria included
operative and postoperative factors, pathologic data including R0 or R1 resection (the pancreatic transection margin and all
transection margins on the specimen were inked). Long-term outcomes were analyzed by tumor recurrence and patient survival.
Results Four cases (8.2%) were converted to open surgery. Overall, Lap SPDP, Lap SxDP, and Lap En/Lap E were performed in 15 (33.3%),
8 (17.8%), and 22 (48.9%) patients, respectively. The operative time and blood loss was significantly lower in the Lap En
group compared with the other laparoscopic techniques. The group of patients with malignant tumors undergoing Lap SxDP had
a longer operating time and greater blood loss compared with the other distal pancreatectomy (Lap DP) techniques. Overall,
the postoperative complications were significantly higher in the Lap En group (42.8%) than in the Lap DP (Lap SPDP + Lap SxDP)
group (22%). These complications were mainly pancreatic fistula: 8.7% after Lap DP and 38% after Lap En. The overall morbidity
was significantly higher after Lap SPDP (26.7%) than after Lap SxDP (12.5%) owing to the occurrence of splenic complications
in the Lap SPDP group without splenic vessel preservation two of seven (28.5%). The means and ranges of hospital stay after
Lap SPDP, Lap SxDP, and Lap En/Lap E were 5.9 (5–14), 7.5 (5–12), and 5.5 (5–7) days, respectively (NS). Pathology examination
of the specimen showed R0 resection in all patients with malignant PNT. The mean time to resumption of previous activities
for patients undergoing Lap DP or Lap En was 3 weeks. There were no postoperative (30 days) or hospital deaths.
Conclusions This series demonstrates that LPS is feasible and safe in benign-appearing and malignant neuroendocrine pancreatic tumors
(NEPTs). The benefits of minimally invasive surgery were manifest in the short hospital stay and acceptable pancreas-related
complications in high-risk patients. LPS can achieve negative tangential margins in a high percentage of patients with malignant
tumors. Although surgical cure is rare in malignant NEPTs, significant long-term palliation can be achieved in a large proportion
of patients with an aggressive surgical approach. 相似文献
55.
Rodríguez Alonso A Cespón Outeda E González Blanco A Bonelli Martín C Lorenzo Franco J Cuerpo Pérez MA Nieto García J 《Actas urologicas espa?olas》2002,26(1):69-73
Duplication of the male urethra is an uncommon congenital malformation. The majority of cases are diagnosed during infancy, and are detected by observing two urethral meatus, or by the appearance of some form of complication, normally of an obstructive nature. Micturitional cystourethrography is an essential test, both in confirming diagnosis of this pathology, and in determining the type of urethral duplication. Excretory urography is also recommended due to its association with other possible urological and extra-urological congenital disorders. Treatment is based on the patient's clinical symptoms, with a waiting period considered advisable for asymptomatic cases. Here we present a case of incomplete urethral duplication, diagnosed from a bladder outlet obstruction, secondary to stenosis of the urethra, which was treated with an endoscopic urethrotomy and distal septotomy, obtaining excellent clinical results. 相似文献
56.
Blanco Parra M Calviño J Romero Burgos R Puñal Rodríguez J Rodríguez-Segade F Lema Grille J Sánchez-Guisande D Varo Pérez E 《Actas urologicas espa?olas》2002,26(8):579-580
Because of the extraperitoneal location, generally used for renal grafting, intraperitoneal urine leaks are a rare complication after transplantation. We report a patient on peritoneal dialysis who developed ascites, abdominal pain, anuria and shock suddenly after renal transplantation. The patient was immediately taken back to the operating room. An abnormal implantation of ureter into the peritoneum overlying the bladder when carrying out an unstented parallel incision extravesical ureterone-ocystostomy was identified. After correcting ureter implantation the patient had immediate diuresis, renal function rapidly improved, with no further complications. Contributing causes were poor exposure, thickened peritoneum secondary to recurrent peritonitis, and the presence of residual peritoneal dialysis fluid. 相似文献
57.
Higher colon cancer tumor proliferative index and lower
tumor cell death rate in mice undergoing laparotomy versus
insufflation 总被引:7,自引:4,他引:7
BACKGROUND: Our laboratory has previously shown that tumors are established more easily and grow larger after laparotomy than after laparoscopy. To characterize these differences in tumor growth further, the tumor cell death rates and tumor proliferation rates were compared in vivo after full sham laparotomy versus carbon dioxide (CO2) insufflation. METHODS: Female Balb/C mice (n = 36) were inoculated intradermally in the dorsal skin with 106 C-26 colon adenocarcinoma cells in 0.1 ml of culture media no more than 1 h before interventions. The mice then were randomized to one of three groups: anesthesia control, CO2 insufflation, or sham laparotomy. The anesthesia control group underwent no procedure. The insufflation group underwent CO2 pneumoperitoneum (4-6 mmHg) for 20 min via a 20-gauge angiocatheter. The laparotomy group underwent a midline incision from xiphoid to pubis, which was closed after 20 min. Tumors were excised from half the mice in each group on postoperative day 7, and from the remaining mice on postoperative day 14. Sections of tumors were made then stained separately for free 3? hydroxyl ends of genomic deoxyribonucleic acid (DNA) using fluorescein-deoxyunidine triphosphate (dUTP), and immunohistochemically for proliferating cell nuclear antigen (PCNA). Apoptosis was measured by quantitating DNA strand breaks in individual cells using fluorescence microscopy. Fluorescein-positive cells in five random high-power fields (x200) were counted in a blinded fashion. The proliferative index of each tumor was determined by averaging PCNA positive cells in five high-power fields (x450) counted in a blinded fashion with the aid of an optical grid. RESULTS: On postoperative day 7, there was no significant difference in the proliferative index or apoptotic rates among the three groups. On postoperative day 14, the proliferative index in the laparotomy group was significantly higher than in either the insufflation or control group (p < 0.001). The proliferative index in the insufflation group also was significantly higher than in the control group (p < 0.05). Inverse differences in apoptotic rates were found. The apoptotic rate in the laparotomy group was significantly lower than in either the insufflation (p < 0.05) or control group (p < 0.001). The apoptotic rate in the insufflation group was significantly lower than in the control group (p < 0.001). CONCLUSIONS: We have demonstrated that there is a significantly higher rate of tumor cell proliferation and a significantly lower rate of tumor cell death with the C-26 colon adenocarcinoma tumor line after laparotomy than after insufflation or anesthesia alone on post-operative day 14. The mechanisms of these phenomena are unclear. It appears that certain factors postoperatively stimulate tumors to proliferate at a higher rate, causing tumor cells to die at a lower rate in the laparotomy group than in the insufflation group. 相似文献
58.
Lorenzo O Ruiz-Ortega M Esbrit P Rupérez M Ortega A Santos S Blanco J Ortega L Egido J 《Journal of the American Society of Nephrology : JASN》2002,13(6):1595-1607
Angiotensin II (AngII) participates in the pathogenesis of kidney damage. Parathyroid hormone (PTH)-related protein (PTHrP), a vasodilator and mitogenic agent, is upregulated during renal injury. The aim of this study was to investigate the potential relation between AngII and PTHrP system in the kidney. Different methods were used to find that both rat mesangial and mouse tubuloepithelial cells express PTHrP and the type 1 PTH/PTHrP receptor (PTH1R). In these cells, AngII increased PTHrP mRNA and protein production. In contrast, PTH1R mRNA was increased in mesangial cells and downregulated in tubular cells, but its protein levels were unmodified in both cells. AT(1) antagonist, but not AT(2), abolished AngII effects on PTHrP/PTH1R. The in vivo effect of AngII was further investigated by systemic infusion (a low dose of 50 ng/kg per min) into normal rats. In controls, PTHrP immunostaining was mainly detected in renal tubules. In AngII-infused rats, PTHrP staining increased in renal tubules and appeared in the glomerulus and the renal vessels. After AngII infusion, PTHR1 staining was markedly increased in all these renal structures at day 3 but remained elevated only in tubules at day 7. The AT(1) antagonist, but not the AT(2), significantly diminished AngII-induced PTHrP and PTHR1 overexpression in the renal tissue, associated with a decrease in tubular damage and fibrosis. The results indicate that AngII regulates renal PTHrP/PTH1R system via AT(1) receptors. These findings demonstrate that PTHrP upregulation occurs in association with the mechanisms of AngII-induced kidney injury. 相似文献
59.
Laureano Fernández-Cruz Rebeca Cosa Laia Blanco Sammy Levi Miguel-Angel López-Boado Salvador Navarro 《Journal of gastrointestinal surgery》2007,11(12):1607-1622
Laparoscopic pancreatic surgery (LPS) has seen significant development but much of the knowledge refers to small and benign
pancreatic tumors. This study aims to evaluate the feasibility, safety, and long-term outcome of the laparoscopic approach
in patients with benign, premalignant, and overt malignant lesions of the pancreas. This study, currently, is the largest
single center experience worldwide. One hundred twenty-three consecutive patients underwent laparoscopic pancreatic surgery
from April 1998 to April 2007, 20 patients with cysts or pseudocysts for acute and chronic pancreatitis, laparoscopic pancreatic
drainage was performed, and were excluded from the analysis. The 103 patients were divided based on preoperative diagnosis:
group I, inflammatory tumors for chronic pancreatitis (eight patients); group II, cystic pancreatic neoplasms (29 patients);
group III, intraductal papillary mucinous neoplasms (10 patients); group IV, neuroendocrine pancreatic tumors (NETs) (43 patients);
and group V ductal adenocarcinoma (13 patients). The median tumor size was 5.3 cm. Pathologic data include R
0 or R
1 resection (transection margins on the specimen were inked). Perioperative data, postoperative complications, and resection
modalities were compared using statistical analysis. Long-term outcomes were analysed by tumor recurrence and patient survival.
The overall conversion rate was 7%. Laparoscopic distal pancreatic resection was performed in 82 patients (79.6%). Laparoscopic
spleen-preserving distal pancreatectomy (Lap SPDP) was performed in 52 patients (63.7%), but with splenic vessels preservation
in 22% and without splenic vessels preservation in 41.5%. Laparoscopic en-bloc splenopancreatectomy (Lap SxDP) was performed
in 30 patients (36.6%) and laparoscopic enucleation (Lap En) in 20 patients (19.4%). There was no mortality. The overall complication
rate was 25.2, 16.7, and 40% after Lap SPDP, Lap SxDP, and Lap En, respectively. The overall morbidity rate was significantly
higher (p > 0.05) in the group of Lap SPDP without splenic vessels preservation comparing with Lap SPDP with splenic vessels preservation
because of the occurrence of splenic complications (20.6%). The overall pancreatic fistulas was 7.7, 10, and 35% after Lap
SPDP, Lap SxDP, and Lap En, respectively; the severity of fistula was significantly higher in the Lap En group (p > 0.05). The mean hospital stay was within 1 week in all groups, except in the group of ductal adenocarcinoma, which is 8 days.
In this series, 27 patients (26.2%) had malignant disease. R
0 resection was achieved in 90% of ductal adenocarcinoma and 100% for other malignant tumors. The median survival for ductal
adenocarcinoma patients was 14 months. This series demonstrates that LPS is feasible and safe in benign-appearing and malignant
lesions of the pancreas. 相似文献
60.