Objective:To compare the clinical effect of transpedicular impaction and grafting of allogeneic bone containing enriched bone marrow combined with posterior internal fixation and posterior subtotal vertebrectomy combined with posterior internal fixation in the treatment of stage III Kümmell′s disease.Methods:A retrospective cohort study was made on clinical data of 40 patients with stage III Kümmell′s disease admitted to Zhengzhou Orthopedic Hospital from June 2015 to December 2018. There were 10 males and 30 females, at age range of 57-79 years［(67.7±6.1)years］. A total of 19 patients were treated by transpedicular impaction and grafting of allogeneic bone containing enriched bone marrow combined with posterior internal fixation (impaction bone graft group), and 21 patients by posterior subtotal vertebrectomy combined with posterior internal fixation (subtotal vertebrectomy group). Operation time and intraoperative blood loss were compared between the two groups. Degree of pain, lumbar dysfunction and degree of kyphosis were evaluated by visual analogue scale (VAS), Japanese Orthopedic Association (JOA) score and kyphotic Cobb angle before operation, at 1 week after operation and at the last follow-up. Bone healing time was compared between the two groups. The complications of the two groups were observed.Results:All patients were followed up for 25-64 months［(40.6±10.4)months］. Operation time and intraoperative blood loss were (130.0±10.1)minutes and (284.5±43.5)ml in impaction bone graft group, lower than those in subtotal vertebrectomy group［(253.8±33.2)minutes, (889.1±95.7)ml］(both P<0.01). There were no significant differences in VAS, JOA score or kyphotic Cobb angle between the two groups before operation, at 1 week after operation and at the last follow-up (all P>0.05). Both VAS and JOA score showed significant differences within each group at any time point (all P<0.01). In both groups, the kyphotic Cobb angle reduced significantly at 1 week after operation when compared with that before operation (all P<0.01), and the angle showed a slight increase at the last follow-up, but remained significantly lower than that before operation (all P<0.01). There were no relapse of pain or aggravation of kyphosis. Bone healing time in impaction bone graft group［4.4(4.0, 5.0)months］was significantly shorter than that in subtotal vertebrectomy group［6.4(5.2, 8.1)months］( P<0.01). There were 2 patients with delayed healing of surgical incision in impaction bone graft group, with the complication rate of 11%. There were 2 patients with dural tear and 3 patients with delayed healing of surgical incision in subtotal vertebrectomy group, with the complication rate of 24%. The complication rate was not statistically significant between the two groups ( P>0.05). No loosening or breakage of internal fixation was observed during the follow-up. Conclusions:Transpedicular impaction and grafting of allogeneic bone containing enriched bone marrow combined with posterior internal fixation and posterior subtotal vertebrectomy combined with posterior internal fixation are effective in the treatment of stage III Kümmell disease. However, the former can shorten the operation time, reduce the intraoperative blood loss and accelerate the healing of injured vertebral bone, suggesting a relatively minimally invasive surgical method for reconstruction and maintenance of spinal biomechanical stability.

Objective:To investigate the clinical value of conventional ultrasound combined with automated breast volume scanner (ABVS) in predicting axillary lymph node metastasis (ALNM) of patients with invasive ductal carcinoma.Methods:A retrospective analysis was performed in 96 patients in the General Hospital of Eastern Theater Command from January 2014 to December 2020. All patients were examined by conventional ultrasound and ABVS before treatment. The patients were divided into the ALNM group and non-axillary lymph node metastasis (N-ALNM) group according to the postoperative pathological results. The differences of ultrasound parameters between the two groups were compared, and Logistic regression was used to analyze the independent predictive factors of ALNM. The ROC curve was plotted to evaluate the diagnostic efficacy for ALNM.Results:Compared with the N-ALNM group, the ALNM group had the characteristics of larger long diameters, unclear boundary, uneven internal echo, Adler blood flow grade Ⅱ-Ⅲ and retraction phenomenon (all P<0.05). Logistic regression analysis showed that the long diameter, uneven internal echo, and retraction phenomenon were independent predictors of ALNM ( OR=1.051, 4.055, 3.493, all P<0.05). The area under curve of ALNM was 0.752(0.653-0.834), the sensitivity and specificity were 54.7% and 83.7%, respectively. Conclusions:The long diameter, uneven internal echo, and retraction phenomenon measured by conventional ultrasound and ABVS are independent predictors of ALNM. The combination of the three can provide imaging references for the evaluation of ALNM of breast cancer.

Objective:To investigate the causes of death and etiological characteristics of skin tissue donors, and to provide reference for allogeneic skin transplantation.Methods:From October 2008 to October 2018, 49 skin tissue donors accepted by the Burn Department of Wuhan Third Hospital met the inclusion criteria of this study, and a cross-sectional study was conducted. According to the cause of death, the donors were divided into accidental death group (19 cases) and non-accidental death group (30 cases). The sex and death age of 49 donors were recorded, and the death age between different sex donors and that of donors between accidental death group and non-accidental death group were compared. Diseases or circumstances that caused the death of donors, hepatitis B, hepatitis C, acquired immunodeficiency syndrome, syphilis virus carrying status, and peripheral blood microbial culture results of 49 donors were recorded, and the detection of blood-borne infectious risk factors of donors between accidental death group and non-accidental death group was compared. Abnormal skin tissue was also selected during allogenic skin graft preparing for pathological examination. Data were statistically analyzed with Mann-Whitney U test and continuity correction chi-square test. Results:(1) Out of the 49 donors in this group, 38 were male (77.55%) and 11 were female (22.45%). The death age was 42.00 (24.00, 55.00) years, and the death age of male donors was similar to that of female donors ( Z=0.120, P>0.05). The death age of donors in accidental death group was lower than that in non-accidental death group, but the difference was not statistically significant ( Z=-1.581, P>0.05). (2) Among the causes and circumstances of the 49 donors in this group, there were 19 cases (38.78%) of injury, poisoning, and some other consequences of external causes, 11 cases (22.45%) of circulatory system diseases, 9 cases (18.37%) of tumors, 3 cases (6.12%) of nervous system diseases, 2 cases (4.08%) of respiratory system diseases, and 2 cases (4.08%) of congenital malformation, deformation, and chromosome abnormality, 1 case (2.04%) of blood and hematopoietic organ diseases and some diseases related to immune mechanism, 1 case (2.04%) of digestive system disease, and 1 case (2.04%) of genitourinary system disease. (3) There were 9 donors (18.37%) with blood-borne infectious risk factors among the 49 donors in this group, including 8 cases (16.33%) of blood-borne infectious diseases, which were 5 cases (10.20%) of hepatitis B, 2 cases (4.08%) of syphilis, and 1 case (2.04%) of hepatitis C, respectively. Blood microorganism culture was positive in 1 case (2.04%), in which multi-drug resistant Pseudomonas aeruginosa was detected. Risk factors of blood-borne infection were detected in 2 donors in accidental death group, with detection ratio lower than that in non-accidental death group (7 cases), but the difference was not statistically significant ( χ2=0.562, P>0.05). (4) A total of 8 donors′ abnormal skin tissue were selected, including 4 cases of intradermal pigmented nevus, 1 case of scar, 1 case of pseudoepithelioma hyperplasia, 1 case of epidermal verrucous hyperplasia, and 1 case of large amount of pigment granules in dermis. Conclusions:Non-accidental death caused by diseases is the main cause of death of skin tissue donors, and the risk of donor-derived infection of non-accidentally dead donors is slightly higher than that of accidentally dead donors. Before the allogeneic skin is obtained and transplanted, the cause of death of the donor should be carefully investigated, and the health status should be evaluated, so as to avoid the occurrence of donor-derived infection.

Objective To study the role of ubiquitin ligase FBW7 in the sensitivity of glioma to temozolomide and its mechanism in glioma cells. Methods FBW7 overexpression lentivirus was constructed. Glioma cell line U251 was divided into 4 groups: the control group, temozolomide group, FBW7 overexpression group, and FBW7 overexpression + temozolomide group. Compared with the intervention on U251 cell lines, the differences of cell inhibitory rates in 4 different groups were analyzed by using contrast microscopy and methyl thiazolyl tetrazolium (MTT) colorimetric assay after 36 h and 72 h respectively. Flow cytometry (FC) was used to determine the cell cycle and apoptosis rate. Results The survival number of U251 cells in the three treatment groups was increased compared with the control group at both 36 h and 72 h. The inhibitory rates of temozolomide group, FBW7 overexpression group, and FBW7 overexpression +temozolomide group at 36 h were (17.6±0.8) ％, (10.4±0.6) ％, (18.6±0.6) ％ respectively compared with the control group (F=67.02, P<0.01); while at 72 h, the inhibitory rates of the three treatment groups were (25.1 ±0.4) ％, (16.7 ±0.7) ％, (29.0 ±0.9) ％ respectively compared with the control group (F= 74.61, P<0.001). Moreover, FBW7 overexpression + temozolomide group presented much greater inhibitory rate than temozolomide group (P<0.01). The G2/M arrest ratio and the cell apoptotic rate at 72 h in the three treatment groups were higher than those in the control group (F=41.63, P<0.001;F=42.30, P<0.01). The increased degree of G2/M arrest ratio and the cell apoptotic rate in FBW7 overexpression + temozolomide group were more obvious compared with temozolomide group (P<0.05, P<0.01). Conclusion FBW7 could enhance the sensitivity of glioma cells to temozolomide treatment, which is associated with G 2/M arrest and the increased apoptosis rate induced by FBW7.

Objective To study the anti-inflammatory,antitussive,and analgesia effects of Jinhua qingre capsules.Methods The anti-inflammatory effect was assessed by the methods include xylene-induced mouse auricular swelling and histamine-induced pigment oozing from skin vessel in rats;The antitussive and analgesic effect were assessed by ammonia water induced cough model and acetic acid-induced twisting method.Results In anti-inflammation experiment,the high dose (12 g·kg-1) and moderate (6 g·kg-1) groups of Jinhua qingre capsules showed significant inhibitory effect on auricular swelling and significant difference compared with control group (P ＜ 0.01,P ＜ 0.05.);the high dose (10 g· kg-1) and moderate dose (5 g·kg-1) groups of Jinhua Qingre capsules play a marked inhibitory role in the increase in mouse peritoneal capillary permeability (P ＜ 0.01,P ＜ 0.05).In antitussive experiment,high dose (12 g· kg-1) and moderate dose (6 g· kg-1) groups had significant inhibitory effect on cough caused by ammonia water (P ＜ 0.01,P ＜ 0.05) compared with control group.In analgesic experiment,the high dose (12 g·kg-1),moderate dose (6 g·kg-1),and low dose (3 g·kg-1) groups effectively reduced the writhing frequency of mice (P ＜ 0.01,P ＜ 0.05).Conclusion Jinhua qingre capsules have potential effects on anti-inflammatory,antitussive,and analgesic.

Objectives To investigate the diagnostic performance of the combination of ultrasound elastography and automated breast volume scanner (ABVS) in differentiation of benign and malignant breast imaging reporting and data system (BI-RADS) 4 breast lesions. Methods Data from 137 breast cancer patients (147 tumors) confirmed pathologically were analyzed. Each tumor was examined by ABVS and ultrasound elastography. All tumors were diagnosed as BI-RADS 4 by ABVS. With final pathology results as the gold standard, the predictive value in differentiating BI-RADS 4 breast lesions between ultrasound elastography and the combination of ultrasound elastography and ABVS were compared. Results There were 54 benign nodules and 93 malignant nodules in this study. The diagnostic sensitivity of ultrasound elastography and the combination of ultrasound elastography and ABVS were 94.6% and 98.9%,the specificity were 57.4% and 57.4%, the accuracy were 81.0% and 83.7%, the area under the curve were 0.858 and 0.965, respectively. The diagnostic performance of ultrasound elastography combined with ABVS was better than that of ultrasound elastography. Conclusions Ultrasound elastography have certain value in differential diagnosis of BI-RADS 4 breast lesions, especially when combining with ABVS, which will improve its diagnostic accuracy. Ultrasound elastography combined with ABVS can improve the detection rate of malignant lesions in BI-RADS 4 breast lesions and reduce the rate of preoperative biopsy, and it has a good application prospect.

Arabinose-5-phosphate isomerase (KdsD) is the first key limiting enzyme in the biosynthesis of 3-deoxy-D-manno-octulosonate (KDO). KdsD gene was cloned into prokaryotic expression vector pET-HTT by seamless DNA cloning method and the amount of soluble recombinant protein was expressed in a soluble form in E. coli BL21 (DE3) after induction of Isopropyl β-D-1-thiogalactopyranoside (IPTG). The target protein was separated and purified by Ni-NTA affinity chromatography and size exclusion chromatography, and its purity was more than 85%. Size exclusion chromatography showed that KdsD protein existed in three forms: polymers, dimmers, and monomers in water solution, different from microbial KdsD enzyme with the four polymers in water solution. Further, the purified protein was identified through Western blotting and MALDI-TOF MASS technology. The results of activity assay showed that the optimum pH and temperature of AtKdsD isomerase activities were 8.0 and 37 ℃, respectively. The enzyme was activated by metal protease inhibitor EDTA (5 mmol/L) and inhibited by some metal ions at lower concentration, especially with Co²⁺ and Cd²⁺ metal ion. Furthermore, when D-arabinose-5-phosphate (A5P) was used as substrate, Km and Vmax of AtKdsD values were 0.16 mmol/L, 0.18 mmol/L·min. The affinity of AtKdsD was higher than KdsD in E. coli combined with substrate. Above results have laid a foundation for the KdsD protein structure and function for its potential industrial application.
Aldose-Ketose Isomerases ; biosynthesis ; Arabidopsis ; enzymology ; Arabidopsis Proteins ; biosynthesis ; Cloning, Molecular ; Escherichia coli ; metabolism ; Metals ; Pentosephosphates ; Recombinant Proteins ; biosynthesis

OBJECTIVETo investigate the clinical manifestation, diagnosis, and treatment of patients with Marjolin's ulcers.

METHODSThe clinical materials of 21 patients with Marjolin's ulcers hospitalized from January 2007 to January 2013 were retrospectively analyzed, including age, gender, injury causes, duration time of primary disease in developing Marjolin's ulcer, duration of ulcer, lesion site, ulcer area, symptoms and signs of ulcer region, bacterial culture results before operation, histopathological type, grade of carcinoma cell differentiation, depth of invasion, treatment, and outcome.

RESULTS(1) The age of 21 patients at the time of diagnosis of Marjolin's ulcers was 19-74 (47 ± 13) years, and the ratio of male to female was nearly 0.9:1.0. (2) The main primary lesions were flame burns and high temperature liquid scald, respectively occurred in 12 cases (57.1%) and 7 cases (33.3%). The time for development of Marjolin's ulcers from primary injury was 10-56 (40 ± 14) years. (3) Ulceration on top of scar lasted for longer than one year in 12 patients (57.1%). (4) Lesion site was mainly located in the limbs in 13 patients (61.9%), and on head and face in 6 patients (28.6%), respectively. (5) Ulcer area ranged 0.25-74.25 (39 ± 25) cm(2). Foul excretion, bleeding, intensified pain, and gradual enlargement of ulceration were observed in the lesion of most patients. (6) Bacterial culture of wound excretion before operation showed positive results in 16 patients (76.2%).

RESULTSof bacterial culture of blood were negative in all patients. (7) Pathological examination revealed squamous cell carcinoma in 20 cases and basal cell carcinoma in 1 case, and mostly of high or medium differentiation. Cancer cells in nearly 40% patients had invaded the subcutaneous tissue or deeper area. (8) All patients were treated by surgery, among them autologous skin grafting was done after excision of lesion in 11 patients, and in 5 patients the defects were closed with skin flaps after excision of lesion, and in 5 patients limbs harboring the lesion were amputated. Twelve patients (57.1%) received postoperative rehabilitation treatment. Two patients with pulmonary metastasis received chemotherapy. (9) Most of the flaps and skin grafts survived well after surgery, and a few cases with failure of skin grafting or transplantation of flaps underwent skin grafts again. Patients were followed up for 6 months to 5 years, in 4 patients recurrence occurred after surgery, and 2 of them died. The other patients survived without recurrence.

CONCLUSIONSSquamous cell carcinoma was the most common pathological type of Marjolin's ulcer admitted to our unit. A recurrent ulcer with long course should be considered as Marjolin's ulcer, and it should be scrutinized pathologically. Currently, surgery remains the optimal treatment for Marjolin's ulcer. Regular follow-up should be carried out after resection of the lesion to detect carcinoma recurrence and metastasis.

Burns ; complications ; Carcinoma, Squamous Cell ; etiology ; pathology ; surgery ; Cicatrix ; Female ; Humans ; Male ; Retrospective Studies ; Skin Neoplasms ; etiology ; pathology ; surgery ; Skin Transplantation ; Skin Ulcer ; etiology ; pathology ; surgery ; Surgical Flaps ; Treatment Outcome

OBJECTIVETo observe the change in phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) signal pathway in monocytes as induced by serum of rats with electrical burn, and to explore the effects of PI3K/Akt pathway on monocyte-endothelial cell adhesion.

METHODSSixty-four SD rats of clean grade were inflicted with electrical burn for the collection of serum of rats with electrical burn; another group of twenty-four SD rats were used to obtain normal serum without treatment. (1) Human monocyte line THP-1 was routinely cultured. The THP-1 cells in logarithmic phase were divided into normal serum group (resuspended in RPMI 1640 medium with 20% normal rat serum) and burn serum group (resuspended with RPMI 1640 medium with 20% serum of rats with electrical burn) according to the random number table, with 6 wells in each group. Morphology of THP-1 cells in normal serum group was observed at post culture hour (PCH) 24, and that in burn serum group at PCH 3, 6, 24. The contents of TNF-α in culture supernatant were determined by double-antibody sandwich ELISA at the corresponding time point in each group. The state of Akt activation was determined by Western blotting at PCH 3, 6, 24. (2) Another portion of THP-1 cells were divided into 4 groups according to the random number table, with 6 wells in each group. Cells in normal serum group and burn serum group were given with the same culture condition as above; cells in normal serum+inhibitor group and burn serum+inhibitor group were cultured with the same culture conditions as in the former two groups correspondingly with addition of 100 nmol/L wortmannin in the nutrient solution. At PCH 3 and 6, THP-1 cells were added into the well with a monolayer of endothelial cell line EA.hy926 to observe the monocyte-endothelial cell adhesion. Data were processed with one-way analysis of variance and LSD- t test.

RESULTS(1) In normal serum group, THP-1 cells showed growth in suspension, with uniform shape at PCH 24. In burn serum group, the cell shape became irregular though the membrane was complete at PCH 3; cellular size became irregular and cell membrane and cytoplasm were swollen at PCH 6; cell membrane was disrupted with death of cells at PCH 24. The contents of TNF-α in culture supernatant in normal serum group at PCH 24 and in burn serum group at PCH 3, 6, 24 were respectively (38.5 ± 1.4), (75.1 ± 1.5), (91.5 ± 1.8), (117.0 ± 1.4) pg/mL (F = 1 415.306, P < 0.01). The contents of TNF-α in culture supernatant in burn serum group at PCH 3, 6, 24 were all significantly higher than the content of TNF-α in normal serum group at PCH 24 (with t values respectively 29.614, 42.852, 63.485, P values below 0.01). The ratio values of phosphorylated Akt to Akt in burn serum group at PCH 3, 6, 24 were respectively 2.66, 3.69, 1.17 times of those in normal serum group at the corresponding time point. (2) In normal serum group, normal serum+inhibitor group, burn serum group, and burn serum+inhibitor group at PCH 3 and 6, the numbers of THP-1 cells adherent to endothelial cells were respectively (231 ± 45), (280 ± 47), (703 ± 169), (335 ± 85) per 100-time field; (219 ± 49), (235 ± 21), (562 ± 123), (226 ± 29) per 100-time field (with F values respectively 25.630 and 18.975, P values below 0.01). The number of THP-1 cells adhered to EA.hy926 cells was significantly more in burn serum group than in normal serum group at PCH 3 and 6 (with t values respectively 6.189 and 6.601, P values below 0.01). The number of THP-1 cells adherent to EA.hy926 cells was significantly fewer in burn serum+inhibitor group than in burn serum group at PCH 3 and 6 (with t values respectively 6.821 and 6.465, P values below 0.01).

CONCLUSIONSThe serum of rats suffering from electrical burn can induce the monocytes to secrete TNF-α, thus enhancing monocyte-endothelial cell adhesion, but it can be inhibited by blocking PI3K/Akt signal pathway.

Animals ; Burns, Electric ; blood ; Cell Line ; Humans ; Monocytes ; Phosphatidylinositol 3-Kinases ; metabolism ; Proto-Oncogene Proteins c-akt ; metabolism ; Rats ; Serum ; Signal Transduction ; Tissue Adhesions ; metabolism ; pathology ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo investigate the mechanism of drug resistance of carbapenems-resistant Acinetobacter baumannii (CRAB) in burn patients and the antimicrobial activity of a combination of drugs against this bacteria in vitro.

METHODSA total of 135 strains of Acinetobacter baumannii (AB) from wound excretion, sputum, and venous catheter wall of patients hospitalized in our department from January 2011 to July 2013 were collected individually. Drug resistance of 135 strains of AB to 12 antibiotics commonly-used in clinic was detected using K-B paper diffusion method. Among the CRAB strains, double-disk synergy test was used to screen metallo-β-lactamase (MBL)-producing strains, and the drug resistance rates between MBL-producing strains and non-MBL-producing strains were compared. Minimal inhibitory concentration (MIC), 50% MIC (MIC50), and 90% MIC (MIC90) of cefoperazone/sulbactam, imipenem, cefepime, ampicillin/sulbactam, and amikacin used alone against MBL-producing CRAB were determined by broth microdilution method. MIC, MIC50, and MIC90 of amikacin respectively combined with imipenem, cefoperazone/sulbactam, cefepime, or ampicillin/sulbactam against MBL-producing CRAB were determined by checkerboard method with diluted agar. Fractional inhibitory concentration (FIC) index was calculated to determine the antibacterial effect of each combination of two antibiotics. Synergy with FIC lower than or equal to 0.5, or additivity with FIC higher than 0.5 and lower than or equal to 1.0 was regarded as effective, and indifference with FIC higher than 1.0 and lower than or equal to 2.0 or antagonism with FIC higher than 2.0 was regarded as ineffective. The effective rate was calculated. Data were processed with Chi-square test.

RESULTSThe resistant rates of the 135 strains of AB to imipenem, meropenem, and ceftazidime were high, and those of piperacillin/tazobactam and ampicillin/sulbactam were low. A total of 120 strains of CRAB was screened, accounting for 88.89%, among which the MBL-producing strains accounted for 78.33% (94/120). The resistant rates of MBL-producing strains to piperacillin/tazobactam, imipenem, meropenem, piperacillin, and cefepime were respectively 59.5%, 87.2%, 93.5%, 87.0%, 86.0%, and they were significantly higher than those of non-MBL-producing strains (respectively 43.0%, 81.3%, 87.5%, 78.4%, 64.0%, with χ(2) values from 4.571 to 8.260, P < 0.05 or P < 0.01). Among the inhibition concentrations of each of the 5 antibiotics used alone against MBL-producing strains, MIC, MIC50, and MIC90 of ampicillin/sulbactam were the lowest, respectively 4.00, 16, 64 µg/mL, while those of cefepime were high, respectively 32.00, 128, 512 µg/mL. MIC, MIC50, and MIC90 of amikacin combined with each of the other 4 antibiotics were decreased from 50.00% to 98.44% as compared with that of single administration of each antibiotic. Among the 94 strains of MBL-producing CRAB, the synergic, additive, indifferent, and antagonistic effects were respectively observed in 40, 33, 6, and 15 strains applied with combination of amikacin and ampicillin/sulbactam; 42, 30, 5, 17 strains applied with combination of amikacin and cefoperazone/sulbactam; 38, 15, 19, 22 strains applied with combination of amikacin and cefepime; 34, 2, 37, 21 strains applied with combination of amikacin and imipenem, among which the antibacterial effective rates decreased successively, respectively 77.7%, 76.6%, 56.4%, and 38.3%. The former two rates were respectively significantly higher than the latter two rates (with χ(2) values from 8.618 to 29.889, P values below 0.01).

CONCLUSIONSProduction of MBL is the main mechanism of resistance of the CRAB isolated from burn patients hospitalized in our department against carbapenems in about 3 years. The antibacterial effects of amikacin combined with each of the former-mentioned 4 agents are better than those of each of the five antibiotics used singly, and the effects are particularly obvious when combining amikacin with compound agent containing enzyme inhibitors.

Acinetobacter Infections ; drug therapy ; microbiology ; Acinetobacter baumannii ; drug effects ; isolation & purification ; Ampicillin ; pharmacology ; Anti-Bacterial Agents ; pharmacology ; Carbapenems ; pharmacology ; Cephalosporins ; pharmacology ; Drug Resistance ; Humans ; In Vitro Techniques ; Microbial Sensitivity Tests ; Penicillanic Acid ; analogs & derivatives ; pharmacology ; Pharmaceutical Preparations ; Piperacillin ; pharmacology ; Sulbactam ; pharmacology ; Thienamycins ; pharmacology ; beta-Lactamase Inhibitors ; pharmacology